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Liu X, de Bakker V, Heggenhougen MV, Mårli MT, Frøynes AH, Salehian Z, Porcellato D, Morales Angeles D, Veening JW, Kjos M. Genome-wide CRISPRi screens for high-throughput fitness quantification and identification of determinants for dalbavancin susceptibility in Staphylococcus aureus. mSystems 2024:e0128923. [PMID: 38837392 DOI: 10.1128/msystems.01289-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Accepted: 05/01/2024] [Indexed: 06/07/2024] Open
Abstract
Antibiotic resistance and tolerance remain a major problem for the treatment of staphylococcal infections. Identifying genes that influence antibiotic susceptibility could open the door to novel antimicrobial strategies, including targets for new synergistic drug combinations. Here, we developed a genome-wide CRISPR interference library for Staphylococcus aureus, demonstrated its use by quantifying gene fitness in different strains through CRISPRi-seq, and used it to identify genes that modulate susceptibility to the lipoglycopeptide dalbavancin. By exposing the library to sublethal concentrations of dalbavancin using both CRISPRi-seq and direct selection methods, we not only found genes previously reported to be involved in antibiotic susceptibility but also identified genes thus far unknown to affect antibiotic tolerance. Importantly, some of these genes could not have been detected by more conventional transposon-based knockout approaches because they are essential for growth, stressing the complementary value of CRISPRi-based methods. Notably, knockdown of a gene encoding the uncharacterized protein KapB specifically sensitizes the cells to dalbavancin, but not to other antibiotics of the same class, whereas knockdown of the Shikimate pathway showed the opposite effect. The results presented here demonstrate the promise of CRISPRi-seq screens to identify genes and pathways involved in antibiotic susceptibility and pave the way to explore alternative antimicrobial treatments through these insights.IMPORTANCEAntibiotic resistance is a challenge for treating staphylococcal infections. Identifying genes that affect how antibiotics work could help create new treatments. In our study, we made a CRISPR interference library for Staphylococcus aureus and used this to find which genes are critical for growth and also mapped genes that are important for antibiotic sensitivity, focusing on the lipoglycopeptide antibiotic dalbavancin. With this method, we identified genes that altered the sensitivity to dalbavancin upon knockdown, including genes involved in different cellular functions. CRISPRi-seq offers a means to uncover untapped antibiotic targets, including those that conventional screens would disregard due to their essentiality. This paves the way for the discovery of new ways to fight infections.
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Affiliation(s)
- Xue Liu
- Department of Pathogen, Biology, International Cancer Center, Shenzhen University Medical School, Shenzhen, Guangdong, China
- Department of Fundamental Microbiology, University of Lausanne, , Switzerland
| | - Vincent de Bakker
- Department of Fundamental Microbiology, University of Lausanne, , Switzerland
| | | | - Marita Torrissen Mårli
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Norway
| | - Anette Heidal Frøynes
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Norway
| | - Zhian Salehian
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Norway
| | - Davide Porcellato
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Norway
| | - Danae Morales Angeles
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Norway
| | - Jan-Willem Veening
- Department of Fundamental Microbiology, University of Lausanne, , Switzerland
| | - Morten Kjos
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Norway
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2
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Böttcher B, Kienast SD, Leufken J, Eggers C, Sharma P, Leufken CM, Morgner B, Drexler HCA, Schulz D, Allert S, Jacobsen ID, Vylkova S, Leidel SA, Brunke S. A highly conserved tRNA modification contributes to C. albicans filamentation and virulence. Microbiol Spectr 2024; 12:e0425522. [PMID: 38587411 PMCID: PMC11064501 DOI: 10.1128/spectrum.04255-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 01/18/2024] [Indexed: 04/09/2024] Open
Abstract
tRNA modifications play important roles in maintaining translation accuracy in all domains of life. Disruptions in the tRNA modification machinery, especially of the anticodon stem loop, can be lethal for many bacteria and lead to a broad range of phenotypes in baker's yeast. Very little is known about the function of tRNA modifications in host-pathogen interactions, where rapidly changing environments and stresses require fast adaptations. We found that two closely related fungal pathogens of humans, the highly pathogenic Candida albicans and its much less pathogenic sister species, Candida dubliniensis, differ in the function of a tRNA-modifying enzyme. This enzyme, Hma1, exhibits species-specific effects on the ability of the two fungi to grow in the hypha morphology, which is central to their virulence potential. We show that Hma1 has tRNA-threonylcarbamoyladenosine dehydratase activity, and its deletion alters ribosome occupancy, especially at 37°C-the body temperature of the human host. A C. albicans HMA1 deletion mutant also shows defects in adhesion to and invasion into human epithelial cells and shows reduced virulence in a fungal infection model. This links tRNA modifications to host-induced filamentation and virulence of one of the most important fungal pathogens of humans.IMPORTANCEFungal infections are on the rise worldwide, and their global burden on human life and health is frequently underestimated. Among them, the human commensal and opportunistic pathogen, Candida albicans, is one of the major causative agents of severe infections. Its virulence is closely linked to its ability to change morphologies from yeasts to hyphae. Here, this ability is linked-to our knowledge for the first time-to modifications of tRNA and translational efficiency. One tRNA-modifying enzyme, Hma1, plays a specific role in C. albicans and its ability to invade the host. This adds a so-far unknown layer of regulation to the fungal virulence program and offers new potential therapeutic targets to fight fungal infections.
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Affiliation(s)
- Bettina Böttcher
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
- Septomics Research Center, Friedrich Schiller University and Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| | - Sandra D. Kienast
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany
- Research Group for Cellular RNA Biochemistry, Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Johannes Leufken
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany
- Research Group for Cellular RNA Biochemistry, Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Cristian Eggers
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany
- Research Group for Cellular RNA Biochemistry, Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Puneet Sharma
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany
- Research Group for Cellular RNA Biochemistry, Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Christine M. Leufken
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Bianka Morgner
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| | - Hannes C. A. Drexler
- Bioanalytical Mass Spectrometry Unit, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Daniela Schulz
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| | - Stefanie Allert
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| | - Ilse D. Jacobsen
- Research Group Microbial Immunology, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
- Institute of Microbiology, Friedrich Schiller University, Jena, Germany
| | - Slavena Vylkova
- Septomics Research Center, Friedrich Schiller University and Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| | - Sebastian A. Leidel
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany
- Research Group for Cellular RNA Biochemistry, Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Sascha Brunke
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
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3
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Leseigneur C, Mondange L, Pizarro-Cerdá J, Dussurget O. Staphylococcus aureus NAD kinase is required for envelop and antibiotic stress responses. Microbes Infect 2024; 26:105334. [PMID: 38556158 DOI: 10.1016/j.micinf.2024.105334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 03/09/2024] [Accepted: 03/28/2024] [Indexed: 04/02/2024]
Abstract
Global burden of infectious diseases and antimicrobial resistance are major public health issues calling for innovative control measures. Bacterial NAD kinase (NADK) is a crucial enzyme for production of NADP(H) and growth. In Staphylococcus aureus, NADK promotes pathogenesis by supporting production of key virulence determinants. Here, we find that knockdown of NADK by CRISPR interference sensitizes S. aureus to osmotic stress and to stresses induced by antibiotics targeting the envelop as well as replication, transcription and translation. Thus, NADK represents a promising target for the development of inhibitors which could be used in combination with current antibiotics.
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Affiliation(s)
- Clarisse Leseigneur
- Institut Pasteur, Université Paris Cité, Microbiology Department, CNRS UMR6047, Yersinia Research Unit, 28 rue du Dr Roux, 75015 Paris, France
| | - Lou Mondange
- Institut Pasteur, Université Paris Cité, Microbiology Department, CNRS UMR6047, Yersinia Research Unit, 28 rue du Dr Roux, 75015 Paris, France; Institut de Recherche Biomédicale des Armées, Microbiology and Infectious Diseases Department, Bacteriology Unit, 91220 Brétigny-sur-Orge, France
| | - Javier Pizarro-Cerdá
- Institut Pasteur, Université Paris Cité, Microbiology Department, CNRS UMR6047, Yersinia Research Unit, 28 rue du Dr Roux, 75015 Paris, France
| | - Olivier Dussurget
- Institut Pasteur, Université Paris Cité, Microbiology Department, CNRS UMR6047, Yersinia Research Unit, 28 rue du Dr Roux, 75015 Paris, France.
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4
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Guo H, Lei T, Yang J, Wang Y, Wang Y, Ji Y. New Insights into the Biological Functions of Essential TsaB/YeaZ Protein in Staphylococcus aureus. Antibiotics (Basel) 2024; 13:393. [PMID: 38786122 PMCID: PMC11117223 DOI: 10.3390/antibiotics13050393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 04/22/2024] [Accepted: 04/24/2024] [Indexed: 05/25/2024] Open
Abstract
TsaB/YeaZ represents a promising target for novel antibacterial agents due to its indispensable role in bacterial survival, high conservation within bacterial species, and absence of eukaryotic homologs. Previous studies have elucidated the role of the essential staphylococcal protein, TsaB/YeaZ, in binding DNA to mediate the transcription of the ilv-leu operon, responsible for encoding key enzymes involved in the biosynthesis of branched-chain amino acids-namely isoleucine, leucine, and valine (ILV). However, the regulation of ILV biosynthesis does not account for the essentiality of TsaB/YeaZ for bacterial growth. In this study, we investigated the impact of TsaB/YeaZ depletion on bacterial morphology and gene expression profiles using electron microscopy and deep transcriptomic analysis, respectively. Our results revealed significant alterations in bacterial size and surface smoothness upon TsaB/YeaZ depletion. Furthermore, we pinpointed specific genes and enriched biological pathways significantly affected by TsaB/YeaZ during the early and middle exponential phases and early stationary phases of growth. Crucially, our research uncovered a regulatory role for TsaB/YeaZ in bacterial autolysis. These discoveries offer fresh insights into the multifaceted biological functions of TsaB/YeaZ within S. aureus.
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Affiliation(s)
- Haiyong Guo
- School of Life Science, Jilin Normal University, Siping 136000, China; (H.G.)
| | - Ting Lei
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108, USA; (T.L.)
| | - Junshu Yang
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108, USA; (T.L.)
| | - Yue Wang
- School of Life Science, Jilin Normal University, Siping 136000, China; (H.G.)
| | - Yifan Wang
- School of Life Science, Jilin Normal University, Siping 136000, China; (H.G.)
| | - Yinduo Ji
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108, USA; (T.L.)
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5
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Smoczynski J, Yared MJ, Meynier V, Barraud P, Tisné C. Advances in the Structural and Functional Understanding of m 1A RNA Modification. Acc Chem Res 2024. [PMID: 38331425 PMCID: PMC10882958 DOI: 10.1021/acs.accounts.3c00568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2024]
Abstract
ConspectusRNA modification is a co- or post-transcriptional process by which specific nucleotides are chemically altered by enzymes after their initial incorporation into the RNA chain, expanding the chemical and functional diversity of RNAs. Our understanding of RNA modifications has changed dramatically in recent years. In the past decade, RNA methyltransferases (MTases) have been highlighted in numerous clinical studies and disease models, modifications have been found to be dynamically regulated by demodification enzymes, and significant technological advances have been made in the fields of RNA sequencing, mass spectrometry, and structural biology. Among RNAs, transfer RNAs (tRNAs) exhibit the greatest diversity and density of post-transcriptional modifications, which allow for potential cross-talks and regulation during their incorporation. N1-methyladenosine (m1A) modification is found in tRNAs at positions 9, 14, 16, 22, 57, and 58, depending on the tRNA and organism.Our laboratory has used and developed a large panel of tools to decipher the different mechanisms used by m1A tRNA MTases to recognize and methylate tRNA. We have solved the structures of TrmI from Thermus thermophilus (m1A58), TrmK from Bacillus subtilis (m1A22), and human TRMT10C (m1A9). These MTases do not share the same structure or organization to recognize tRNAs, but they all modify an adenosine, forming a non-Watson-Crick (WC) interaction. For TrmK, nuclear magnetic resonance (NMR) chemical shift mapping of the binding interface between TrmK and tRNASer was invaluable to build a TrmK/tRNA model, where both domains of TrmK participate in the binding of a full-length L-shaped tRNA and where the non-WC purine 13-A22 base pair positions the A22 N1-atom close to the methyl of the S-adenosyl-l-methionine (SAM) TrmK cofactor. For TRMT10C, cryoEM structures showed the MTase poised to N1-methylate A9 or G9 in tRNA and revealed different steps of tRNA maturation, where TRMT10C acts as a tRNA binding platform for sequential docking of each maturation enzyme. This work confers a role for TRMT10C in tRNA quality control and provides a framework to understand the link between mitochondrial tRNA maturation dysfunction and diseases.Methods to directly detect the incorporation of modifications during tRNA biosynthesis are rare and do not provide easy access to the temporality of their introduction. To this end, we have introduced time-resolved NMR to monitor tRNA maturation in the cellular environment. Combined with genetic and biochemical approaches involving the synthesis of specifically modified tRNAs, our methodology revealed that some modifications are incorporated in a defined sequential order, controlled by cross-talks between modification events. In particular, a strong modification circuit, namely Ψ55 → m5U54 → m1A58, controls the modification process in the T-arm of yeast elongator tRNAs. Conversely, we showed that m1A58 is efficiently introduced on unmodified initiator tRNAiMet without the need of any prior modification. Two distinct pathways are therefore followed for m1A58 incorporation in elongator and initiator tRNAs.We are undoubtedly entering an exciting period for the elucidation of the functions of RNA modifications and the intricate mechanisms by which modification enzymes identify and alter their RNA substrates. These are promising directions for the field of epitranscriptomics.
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Affiliation(s)
- Jakub Smoczynski
- Université Paris Cité, CNRS, Institut de Biologie Physico-Chimique, IBPC, Expression Génétique Microbienne, Paris 75005, France
| | - Marcel-Joseph Yared
- Université Paris Cité, CNRS, Institut de Biologie Physico-Chimique, IBPC, Expression Génétique Microbienne, Paris 75005, France
| | - Vincent Meynier
- Université Paris Cité, CNRS, Institut de Biologie Physico-Chimique, IBPC, Expression Génétique Microbienne, Paris 75005, France
| | - Pierre Barraud
- Université Paris Cité, CNRS, Institut de Biologie Physico-Chimique, IBPC, Expression Génétique Microbienne, Paris 75005, France
| | - Carine Tisné
- Université Paris Cité, CNRS, Institut de Biologie Physico-Chimique, IBPC, Expression Génétique Microbienne, Paris 75005, France
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6
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Reed P, Sorg M, Alwardt D, Serra L, Veiga H, Schäper S, Pinho MG. A CRISPRi-based genetic resource to study essential Staphylococcus aureus genes. mBio 2024; 15:e0277323. [PMID: 38054745 PMCID: PMC10870820 DOI: 10.1128/mbio.02773-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 10/19/2023] [Indexed: 12/07/2023] Open
Abstract
IMPORTANCE Staphylococcus aureus is an important clinical pathogen that causes a high number of antibiotic-resistant infections. The study of S. aureus biology, and particularly of the function of essential proteins, is of particular importance to develop new approaches to combat this pathogen. We have optimized a clustered regularly interspaced short palindromic repeat interference (CRISPRi) system that allows efficient targeting of essential S. aureus genes. Furthermore, we have used that system to construct a library comprising 261 strains, which allows the depletion of essential proteins encoded by 200 genes/operons. This library, which we have named Lisbon CRISPRi Mutant Library, should facilitate the study of S. aureus pathogenesis and biology.
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Affiliation(s)
- Patricia Reed
- Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Moritz Sorg
- Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Dominik Alwardt
- Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Lúcia Serra
- Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Helena Veiga
- Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Simon Schäper
- Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Mariana G. Pinho
- Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
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7
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Gómez Borrego J, Torrent Burgas M. Structural assembly of the bacterial essential interactome. eLife 2024; 13:e94919. [PMID: 38226900 PMCID: PMC10863985 DOI: 10.7554/elife.94919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 12/22/2023] [Indexed: 01/17/2024] Open
Abstract
The study of protein interactions in living organisms is fundamental for understanding biological processes and central metabolic pathways. Yet, our knowledge of the bacterial interactome remains limited. Here, we combined gene deletion mutant analysis with deep-learning protein folding using AlphaFold2 to predict the core bacterial essential interactome. We predicted and modeled 1402 interactions between essential proteins in bacteria and generated 146 high-accuracy models. Our analysis reveals previously unknown details about the assembly mechanisms of these complexes, highlighting the importance of specific structural features in their stability and function. Our work provides a framework for predicting the essential interactomes of bacteria and highlight the potential of deep-learning algorithms in advancing our understanding of the complex biology of living organisms. Also, the results presented here offer a promising approach to identify novel antibiotic targets.
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Affiliation(s)
- Jordi Gómez Borrego
- Systems Biology of Infection Lab, Department of Biochemistry and Molecular Biology, Biosciences Faculty, Universitat Autònoma de BarcelonaCerdanyola del VallèsSpain
| | - Marc Torrent Burgas
- Systems Biology of Infection Lab, Department of Biochemistry and Molecular Biology, Biosciences Faculty, Universitat Autònoma de BarcelonaCerdanyola del VallèsSpain
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8
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Gwynne PJ, Stocks KLK, Karozichian ES, Pandit A, Hu LT. Metabolic modeling predicts unique drug targets in Borrelia burgdorferi. mSystems 2023; 8:e0083523. [PMID: 37855615 PMCID: PMC10734484 DOI: 10.1128/msystems.00835-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 08/22/2023] [Indexed: 10/20/2023] Open
Abstract
IMPORTANCE Lyme disease is often treated using long courses of antibiotics, which can cause side effects for patients and risks the evolution of antimicrobial resistance. Narrow-spectrum antimicrobials would reduce these risks, but their development has been slow because the Lyme disease bacterium, Borrelia burgdorferi, is difficult to work with in the laboratory. To accelerate the drug discovery pipeline, we developed a computational model of B. burgdorferi's metabolism and used it to predict essential enzymatic reactions whose inhibition prevented growth in silico. These predictions were validated using small-molecule enzyme inhibitors, several of which were shown to have specific activity against B. burgdorferi. Although the specific compounds used are not suitable for clinical use, we aim to use them as lead compounds to develop optimized drugs targeting the pathways discovered here.
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Affiliation(s)
- Peter J. Gwynne
- Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, USA
- Tufts Lyme Disease Initiative, Tufts University, Boston, Massachusetts, USA
| | - Kee-Lee K. Stocks
- Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, USA
- Tufts Lyme Disease Initiative, Tufts University, Boston, Massachusetts, USA
| | - Elysse S. Karozichian
- Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, USA
- Tufts Lyme Disease Initiative, Tufts University, Boston, Massachusetts, USA
| | - Aarya Pandit
- Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, USA
- Tufts Lyme Disease Initiative, Tufts University, Boston, Massachusetts, USA
| | - Linden T. Hu
- Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, USA
- Tufts Lyme Disease Initiative, Tufts University, Boston, Massachusetts, USA
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9
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Douglas EA, Marshall B, Alghamadi A, Joseph EA, Duggan S, Vittorio S, De Luca L, Serpi M, Laabei M. Improved Antibacterial Activity of 1,3,4-Oxadiazole-Based Compounds That Restrict Staphylococcus aureus Growth Independent of LtaS Function. ACS Infect Dis 2023; 9:2141-2159. [PMID: 37828912 PMCID: PMC10644342 DOI: 10.1021/acsinfecdis.3c00250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Indexed: 10/14/2023]
Abstract
The lipoteichoic acid (LTA) biosynthesis pathway has emerged as a promising antimicrobial therapeutic target. Previous studies identified the 1,3,4 oxadiazole compound 1771 as an LTA inhibitor with activity against Gram-positive pathogens. We have succeeded in making six 1771 derivatives and, through subsequent hit validation, identified the incorporation of a pentafluorosulfanyl substituent as central in enhancing activity. Our newly described derivative, compound 13, showed a 16- to 32-fold increase in activity compared to 1771 when tested against a cohort of multidrug-resistant Staphylococcus aureus strains while simultaneously exhibiting an improved toxicity profile against mammalian cells. Molecular techniques were employed in which the assumed target, lipoteichoic acid synthase (LtaS), was both deleted and overexpressed. Neither deletion nor overexpression of LtaS altered 1771 or compound 13 susceptibility; however, overexpression of LtaS increased the MIC of Congo red, a previously identified LtaS inhibitor. These data were further supported by comparing the docking poses of 1771 and derivatives in the LtaS active site, which indicated the possibility of an additional target(s). Finally, we show that both 1771 and compound 13 have activity that is independent of LtaS, extending to cover Gram-negative species if the outer membrane is first permeabilized, challenging the classification that these compounds are strict LtaS inhibitors.
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Affiliation(s)
| | - Brandon Marshall
- School
of Chemistry, Cardiff University, Cardiff CF10 3AT, Wales, U.K.
| | - Arwa Alghamadi
- School
of Chemistry, Cardiff University, Cardiff CF10 3AT, Wales, U.K.
| | - Erin A. Joseph
- School
of Chemistry, Cardiff University, Cardiff CF10 3AT, Wales, U.K.
| | - Seána Duggan
- Medical
Research Council Centre for Medical Mycology at the University of
Exeter, University of Exeter, Exeter EX4 4DQ, U.K.
| | - Serena Vittorio
- Department
of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Messina I-98125, Italy
| | - Laura De Luca
- Department
of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Messina I-98125, Italy
| | - Michaela Serpi
- School
of Chemistry, Cardiff University, Cardiff CF10 3AT, Wales, U.K.
| | - Maisem Laabei
- Department
of Life Sciences, University of Bath, Bath BA2 7AY, U.K.
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10
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Toyomoto T, Ono K, Shiba T, Momitani K, Zhang T, Tsutsuki H, Ishikawa T, Hoso K, Hamada K, Rahman A, Wen L, Maeda Y, Yamamoto K, Matsuoka M, Hanaoka K, Niidome T, Akaike T, Sawa T. Alkyl gallates inhibit serine O-acetyltransferase in bacteria and enhance susceptibility of drug-resistant Gram-negative bacteria to antibiotics. Front Microbiol 2023; 14:1276447. [PMID: 37965540 PMCID: PMC10641863 DOI: 10.3389/fmicb.2023.1276447] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Accepted: 10/12/2023] [Indexed: 11/16/2023] Open
Abstract
A principal concept in developing antibacterial agents with selective toxicity is blocking metabolic pathways that are critical for bacterial growth but that mammalian cells lack. Serine O-acetyltransferase (CysE) is an enzyme in many bacteria that catalyzes the first step in l-cysteine biosynthesis by transferring an acetyl group from acetyl coenzyme A (acetyl-CoA) to l-serine to form O-acetylserine. Because mammalian cells lack this l-cysteine biosynthesis pathway, developing an inhibitor of CysE has been thought to be a way to establish a new class of antibacterial agents. Here, we demonstrated that alkyl gallates such as octyl gallate (OGA) could act as potent CysE inhibitors in vitro and in bacteria. Mass spectrometry analyses indicated that OGA treatment markedly reduced intrabacterial levels of l-cysteine and its metabolites including glutathione and glutathione persulfide in Escherichia coli to a level similar to that found in E. coli lacking the cysE gene. Consistent with the reduction of those antioxidant molecules in bacteria, E. coli became vulnerable to hydrogen peroxide-mediated bacterial killing in the presence of OGA. More important, OGA treatment intensified susceptibilities of metallo-β-lactamase-expressing Gram-negative bacteria (E. coli and Klebsiella pneumoniae) to carbapenem. Structural analyses showed that alkyl gallate bound to the binding site for acetyl-CoA that limits access of acetyl-CoA to the active site. Our data thus suggest that CysE inhibitors may be used to treat infectious diseases caused by drug-resistant Gram-negative bacteria not only via direct antibacterial activity but also by enhancing therapeutic potentials of existing antibiotics.
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Affiliation(s)
- Touya Toyomoto
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Katsuhiko Ono
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Tomoo Shiba
- Department of Applied Biology, Graduate School of Science and Technology, Kyoto Institute of Technology, Kyoto, Japan
| | - Kenta Momitani
- Department of Applied Biology, Graduate School of Science and Technology, Kyoto Institute of Technology, Kyoto, Japan
| | - Tianli Zhang
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Hiroyasu Tsutsuki
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Takeshi Ishikawa
- Department of Chemistry, Biotechnology, and Chemical Engineering, Graduate School of Science and Engineering, Kagoshima University, Kagoshima, Japan
| | - Kanae Hoso
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Koma Hamada
- Faculty of Advanced Science and Technology, Kumamoto University, Kumamoto, Japan
| | - Azizur Rahman
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Liping Wen
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Yosuke Maeda
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Keiichi Yamamoto
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Masao Matsuoka
- Department of Hematology, Rheumatology, and Infectious Diseases, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Kenjiro Hanaoka
- Graduate School of Pharmaceutical Sciences, Keio University, Tokyo, Japan
| | - Takuro Niidome
- Faculty of Advanced Science and Technology, Kumamoto University, Kumamoto, Japan
| | - Takaaki Akaike
- Department of Environmental Medicine and Molecular Toxicology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Tomohiro Sawa
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
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11
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Bogut A, Koper P, Marczak M, Całka P. The first genomic characterization of a stable, hemin-dependent small colony variant strain of Staphylococcus epidermidis isolated from a prosthetic-joint infection. Front Microbiol 2023; 14:1289844. [PMID: 37928677 PMCID: PMC10620731 DOI: 10.3389/fmicb.2023.1289844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Accepted: 10/05/2023] [Indexed: 11/07/2023] Open
Abstract
Phenotype switching from a wild type (WT) to a slow-growing subpopulation, referred to as small colony variants (SCVs), supports an infectious lifestyle of Staphylococcus epidermidis, the leading cause of medical device-related infections. Specific mechanisms underlying formation of SCVs and involved in the shaping of their pathogenic potential are of particular interest for stable strains as they have been only rarely cultured from clinical specimens. As the SCV phenotype stability implies the existence of genetic changes, the whole genome sequence of a stable, hemin-dependent S. epidermidis SCV strain (named 49SCV) involved in a late prosthetic joint infection was analyzed. The strain was isolated in a monoculture without a corresponding WT clone, therefore, its genome was compared against five reference S. epidermidis strains (ATCC12228, ATCC14990, NBRC113846, O47, and RP62A), both at the level of the genome structure and coding sequences. According to the Multilocus Sequence Typing analysis, the 49SCV strain represented the sequence type 2 (ST2) regarded as the most prominent infection-causing lineage with a worldwide dissemination. Genomic features unique to 49SCV included the absence of the Staphylococcal Cassette Chromosome (SCC), ~12 kb deletion with the loss of genes involved in the arginine deiminase pathway, and frameshift-generating mutations within the poly(A) and poly(T) homopolymeric tracts. Indels were identified in loci associated with adherence, metabolism, stress response, virulence, and cell wall synthesis. Of note, deletion in the poly(A) of the hemA gene has been considered a possible trigger factor for the phenotype transition and hemin auxotrophy in the strain. To our knowledge, the study represents the first genomic characterization of a clinical, stable and hemin-dependent S. epidermidis SCV strain. We propose that previously unreported indels in the homopolymeric tracts can constitute a background of the SCV phenotype due to a resulting truncation of the corresponding proteins and their possible biological dysfunction. Streamline of genetic content evidenced by the loss of the SCC and a large genomic deletion can represent a possible strategy associated both with the SCV phenotype and its adaptation to chronicity.
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Affiliation(s)
- Agnieszka Bogut
- Chair and Department of Medical Microbiology, Medical University of Lublin, Lublin, Poland
| | - Piotr Koper
- Department of Genetics and Microbiology, Institute of Biological Sciences, Maria Curie-Skłodowska University, Lublin, Poland
| | - Małgorzata Marczak
- Department of Genetics and Microbiology, Institute of Biological Sciences, Maria Curie-Skłodowska University, Lublin, Poland
| | - Paulina Całka
- Chair and Department of Forensic Medicine, Medical University of Lublin, Lublin, Poland
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12
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Sharkey LKR, Guerillot R, Walsh CJ, Turner AM, Lee JYH, Neville SL, Klatt S, Baines SL, Pidot SJ, Rossello FJ, Seemann T, McWilliam HEG, Cho E, Carter GP, Howden BP, McDevitt CA, Hachani A, Stinear TP, Monk IR. The two-component system WalKR provides an essential link between cell wall homeostasis and DNA replication in Staphylococcus aureus. mBio 2023; 14:e0226223. [PMID: 37850732 PMCID: PMC10746227 DOI: 10.1128/mbio.02262-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 09/05/2023] [Indexed: 10/19/2023] Open
Abstract
Among the 16 two-component systems in the opportunistic human pathogen Staphylococcus aureus, only WalKR is essential. Like the orthologous systems in other Bacillota, S. aureus WalKR controls autolysins involved in peptidoglycan remodeling and is therefore intimately involved in cell division. However, despite the importance of WalKR in S. aureus, the basis for its essentiality is not understood and the regulon is poorly defined. Here, we defined a consensus WalR DNA-binding motif and the direct WalKR regulon by using functional genomics, including chromatin immunoprecipitation sequencing, with a panel of isogenic walKR mutants that had a spectrum of altered activities. Consistent with prior findings, the direct regulon includes multiple autolysin genes. However, this work also revealed that WalR directly regulates at least five essential genes involved in lipoteichoic acid synthesis (ltaS): translation (rplK), DNA compaction (hup), initiation of DNA replication (dnaA, hup) and purine nucleotide metabolism (prs). Thus, WalKR in S. aureus serves as a polyfunctional regulator that contributes to fundamental control over critical cell processes by coordinately linking cell wall homeostasis with purine biosynthesis, protein biosynthesis, and DNA replication. Our findings further address the essentiality of this locus and highlight the importance of WalKR as a bona fide target for novel anti-staphylococcal therapeutics. IMPORTANCE The opportunistic human pathogen Staphylococcus aureus uses an array of protein sensing systems called two-component systems (TCS) to sense environmental signals and adapt its physiology in response by regulating different genes. This sensory network is key to S. aureus versatility and success as a pathogen. Here, we reveal for the first time the full extent of the regulatory network of WalKR, the only staphylococcal TCS that is indispensable for survival under laboratory conditions. We found that WalKR is a master regulator of cell growth, coordinating the expression of genes from multiple, fundamental S. aureus cellular processes, including those involved in maintaining cell wall metabolism, protein biosynthesis, nucleotide metabolism, and the initiation of DNA replication.
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Affiliation(s)
- Liam K. R. Sharkey
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Romain Guerillot
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Calum J. Walsh
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Adrianna M. Turner
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Jean Y. H. Lee
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Stephanie L. Neville
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Stephan Klatt
- The Florey Institute of Neuroscience and Mental Health, Melbourne Dementia Research Centre, The University of Melbourne, Parkville, Victoria, Australia
| | - Sarah L. Baines
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Sacha J. Pidot
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Fernando J. Rossello
- University of Melbourne Centre for Cancer Research, The University of Melbourne, Melbourne, Victoria, Australia
- Australian Regenerative Medicine Institute, Monash University, Melbourne, Victoria, Australia
| | - Torsten Seemann
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
- Department of Microbiology and Immunology, Centre for Pathogen Genomics, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Hamish E. G. McWilliam
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Ellie Cho
- Biological Optical Microscopy Platform, University of Melbourne, Melbourne, Victoria, Australia
| | - Glen P. Carter
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Benjamin P. Howden
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
- Department of Microbiology and Immunology, Centre for Pathogen Genomics, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Christopher A. McDevitt
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Abderrahman Hachani
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Timothy P. Stinear
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
- Department of Microbiology and Immunology, Centre for Pathogen Genomics, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | - Ian R. Monk
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
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13
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Freiberg JA, Ruiz VMR, Green ER, Skaar EP. Restriction of Arginine Induces Antibiotic Tolerance in Staphylococcus aureus. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.12.561972. [PMID: 37873095 PMCID: PMC10592767 DOI: 10.1101/2023.10.12.561972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Staphylococcus aureus is responsible for a substantial number of invasive infections globally each year. These infections are problematic because they are frequently recalcitrant to antibiotic treatment, particularly when they are caused by Methicillin-Resistant Staphylococcus aureus (MRSA). Antibiotic tolerance, the ability for bacteria to persist despite normally lethal doses of antibiotics, is responsible for most antibiotic treatment failure in MRSA infections. To understand how antibiotic tolerance is induced, S. aureus biofilms exposed to multiple anti-MRSA antibiotics (vancomycin, ceftaroline, delafloxacin, and linezolid) were examined using both quantitative proteomics and transposon sequencing. These screens indicated that arginine metabolism is involved in antibiotic tolerance within a biofilm and led to the hypothesis that depletion of arginine within S. aureus communities can induce antibiotic tolerance. Consistent with this hypothesis, inactivation of argH, the final gene in the arginine synthesis pathway, induces antibiotic tolerance under conditions in which the parental strain is susceptible to antibiotics. Arginine restriction was found to induce antibiotic tolerance via inhibition of protein synthesis. Finally, although S. aureus fitness in a mouse skin infection model is decreased in an argH mutant, its ability to survive in vivo during antibiotic treatment with vancomycin is enhanced, highlighting the relationship between arginine metabolism and antibiotic tolerance during S. aureus infection. Uncovering this link between arginine metabolism and antibiotic tolerance has the potential to open new therapeutic avenues targeting previously recalcitrant S. aureus infections.
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Affiliation(s)
- Jeffrey A. Freiberg
- Division of Infectious Diseases, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN 37232
| | - Valeria M. Reyes Ruiz
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN 37232
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232
| | - Erin R. Green
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN 37232
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232
- Department of Microbiology, University of Chicago, Chicago, IL 60637
| | - Eric P. Skaar
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN 37232
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232
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14
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Debard F, Desicy-Huiez Q, Kehiha S, Laudouze J, Vizzari M, Latifi A. [Discovery of the cornerstone ensuring the coordination of the synthesis of the bacterial wall with the central metabolism]. Med Sci (Paris) 2023; 39:681-685. [PMID: 37695160 DOI: 10.1051/medsci/2023105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/12/2023] Open
Affiliation(s)
- Fabian Debard
- Master 2 Microbiologie intégrative et fondamentale, Aix Marseille université, Marseille, France
| | - Quentin Desicy-Huiez
- Master 2 Microbiologie intégrative et fondamentale, Aix Marseille université, Marseille, France
| | - Samya Kehiha
- Master 2 Microbiologie intégrative et fondamentale, Aix Marseille université, Marseille, France
| | - Janis Laudouze
- Master 2 Microbiologie intégrative et fondamentale, Aix Marseille université, Marseille, France
| | - Marvin Vizzari
- Master 2 Microbiologie intégrative et fondamentale, Aix Marseille université, Marseille, France
| | - Amel Latifi
- Aix Marseille université, CNRS, LCB UMR7283, IMM, Marseille, France
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15
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Patel H, Rawat S. A genetic regulatory see-saw of biofilm and virulence in MRSA pathogenesis. Front Microbiol 2023; 14:1204428. [PMID: 37434702 PMCID: PMC10332168 DOI: 10.3389/fmicb.2023.1204428] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 05/30/2023] [Indexed: 07/13/2023] Open
Abstract
Staphylococcus aureus is one of the most common opportunistic human pathogens causing several infectious diseases. Ever since the emergence of the first methicillin-resistant Staphylococcus aureus (MRSA) strain decades back, the organism has been a major cause of hospital-acquired infections (HA-MRSA). The spread of this pathogen across the community led to the emergence of a more virulent subtype of the strain, i.e., Community acquired Methicillin resistant Staphylococcus aureus (CA-MRSA). Hence, WHO has declared Staphylococcus aureus as a high-priority pathogen. MRSA pathogenesis is remarkable because of the ability of this "superbug" to form robust biofilm both in vivo and in vitro by the formation of polysaccharide intercellular adhesin (PIA), extracellular DNA (eDNA), wall teichoic acids (WTAs), and capsule (CP), which are major components that impart stability to a biofilm. On the other hand, secretion of a diverse array of virulence factors such as hemolysins, leukotoxins, enterotoxins, and Protein A regulated by agr and sae two-component systems (TCS) aids in combating host immune response. The up- and downregulation of adhesion genes involved in biofilm formation and genes responsible for synthesizing virulence factors during different stages of infection act as a genetic regulatory see-saw in the pathogenesis of MRSA. This review provides insight into the evolution and pathogenesis of MRSA infections with a focus on genetic regulation of biofilm formation and virulence factors secretion.
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Affiliation(s)
| | - Seema Rawat
- Microbiology Laboratory, School of Life Sciences, Central University of Gujarat, Gandhinagar, Gujarat, India
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16
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Fuss MF, Wieferig JP, Corey RA, Hellmich Y, Tascón I, Sousa JS, Stansfeld PJ, Vonck J, Hänelt I. Cyclic di-AMP traps proton-coupled K + transporters of the KUP family in an inward-occluded conformation. Nat Commun 2023; 14:3683. [PMID: 37344476 DOI: 10.1038/s41467-023-38944-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Accepted: 05/22/2023] [Indexed: 06/23/2023] Open
Abstract
Cyclic di-AMP is the only known essential second messenger in bacteria and archaea, regulating different proteins indispensable for numerous physiological processes. In particular, it controls various potassium and osmolyte transporters involved in osmoregulation. In Bacillus subtilis, the K+/H+ symporter KimA of the KUP family is inactivated by c-di-AMP. KimA sustains survival at potassium limitation at low external pH by mediating potassium ion uptake. However, at elevated intracellular K+ concentrations, further K+ accumulation would be toxic. In this study, we reveal the molecular basis of how c-di-AMP binding inhibits KimA. We report cryo-EM structures of KimA with bound c-di-AMP in detergent solution and reconstituted in amphipols. By combining structural data with functional assays and molecular dynamics simulations we reveal how c-di-AMP modulates transport. We show that an intracellular loop in the transmembrane domain interacts with c-di-AMP bound to the adjacent cytosolic domain. This reduces the mobility of transmembrane helices at the cytosolic side of the K+ binding site and therefore traps KimA in an inward-occluded conformation.
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Affiliation(s)
- Michael F Fuss
- Institute of Biochemistry, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Jan-Philip Wieferig
- Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt am Main, Germany
| | - Robin A Corey
- Department of Biochemistry, University of Oxford, Oxford, UK
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - Yvonne Hellmich
- Institute of Biochemistry, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Igor Tascón
- Institute of Biochemistry, Goethe University Frankfurt, Frankfurt am Main, Germany
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, Leioa, Spain
- Ikerbasque, Basque Foundation for Science, Bilbao, Spain
| | - Joana S Sousa
- Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt am Main, Germany
- UCB Pharma, UCB Biopharma UK, Slough, SL1 3WE, UK
| | - Phillip J Stansfeld
- School of Life Sciences & Department of Chemistry, University of Warwick, Coventry, CV4 7AL, UK
| | - Janet Vonck
- Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt am Main, Germany.
| | - Inga Hänelt
- Institute of Biochemistry, Goethe University Frankfurt, Frankfurt am Main, Germany.
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17
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Pensinger DA, Gutierrez KV, Smith HB, Vincent WJB, Stevenson DS, Black KA, Perez-Medina KM, Dillard JP, Rhee KY, Amador-Noguez D, Huynh TN, Sauer JD. Listeria monocytogenes GlmR Is an Accessory Uridyltransferase Essential for Cytosolic Survival and Virulence. mBio 2023; 14:e0007323. [PMID: 36939339 PMCID: PMC10128056 DOI: 10.1128/mbio.00073-23] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 02/14/2023] [Indexed: 03/21/2023] Open
Abstract
The cytosol of eukaryotic host cells is an intrinsically hostile environment for bacteria. Understanding how cytosolic pathogens adapt to and survive in the cytosol is critical to developing novel therapeutic interventions against these pathogens. The cytosolic pathogen Listeria monocytogenes requires glmR (previously known as yvcK), a gene of unknown function, for resistance to cell-wall stress, cytosolic survival, inflammasome avoidance, and, ultimately, virulence in vivo. In this study, a genetic suppressor screen revealed that blocking utilization of UDP N-acetylglucosamine (UDP-GlcNAc) by a nonessential wall teichoic acid decoration pathway restored resistance to lysozyme and partially restored virulence of ΔglmR mutants. In parallel, metabolomic analysis revealed that ΔglmR mutants are impaired in the production of UDP-GlcNAc, an essential peptidoglycan and wall teichoic acid (WTA) precursor. We next demonstrated that purified GlmR can directly catalyze the synthesis of UDP-GlcNAc from GlcNAc-1P and UTP, suggesting that it is an accessory uridyltransferase. Biochemical analysis of GlmR orthologues suggests that uridyltransferase activity is conserved. Finally, mutational analysis resulting in a GlmR mutant with impaired catalytic activity demonstrated that uridyltransferase activity was essential to facilitate cell-wall stress responses and virulence in vivo. Taken together, these studies indicate that GlmR is an evolutionary conserved accessory uridyltransferase required for cytosolic survival and virulence of L. monocytogenes. IMPORTANCE Bacterial pathogens must adapt to their host environment in order to cause disease. The cytosolic bacterial pathogen Listeria monocytogenes requires a highly conserved protein of unknown function, GlmR (previously known as YvcK), to survive in the host cytosol. GlmR is important for resistance to some cell-wall stresses and is essential for virulence. The ΔglmR mutant is deficient in production of an essential cell-wall metabolite, UDP-GlcNAc, and suppressors that increase metabolite levels also restore virulence. Purified GlmR can directly catalyze the synthesis of UDP-GlcNAc, and this enzymatic activity is conserved in both Bacillus subtilis and Staphylococcus aureus. These results highlight the importance of accessory cell wall metabolism enzymes in responding to cell-wall stress in a variety of Gram-positive bacteria.
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Affiliation(s)
- Daniel A Pensinger
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Kimberly V Gutierrez
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Hans B Smith
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - William J B Vincent
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - David S Stevenson
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | | | - Krizia M Perez-Medina
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Joseph P Dillard
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Kyu Y Rhee
- Weill Cornell Medical College, New York, New York, USA
| | - Daniel Amador-Noguez
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - TuAnh N Huynh
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Department of Food Science, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - John-Demian Sauer
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
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18
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Clément DA, Gelin M, Leseigneur C, Huteau V, Mondange L, Pons JL, Dussurget O, Lionne C, Labesse G, Pochet S. Synthesis and structure-activity relationship studies of original cyclic diadenosine derivatives as nanomolar inhibitors of NAD kinase from pathogenic bacteria. Eur J Med Chem 2023; 246:114941. [PMID: 36455355 DOI: 10.1016/j.ejmech.2022.114941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/15/2022] [Accepted: 11/16/2022] [Indexed: 11/24/2022]
Abstract
Nicotinamide adenine dinucleotide kinases (NAD kinases) are essential and ubiquitous enzymes involved in the production of NADP(H) which is an essential cofactor in many metabolic pathways. Targeting NAD kinase (NADK), a rate limiting enzyme of NADP biosynthesis pathway, represents a new promising approach to treat bacterial infections. Previously, we have produced the first NADK inhibitor active against staphylococcal infection. From this linear di-adenosine derivative, namely NKI1, we designed macrocyclic analogues. Here, we describe the synthesis and evaluation of an original series of cyclic diadenosine derivatives as NADK inhibitors of two pathogenic bacteria, Listeria monocytogenes and Staphylococcus aureus. The nature and length of the link between the two adenosine units were examined leading to sub-micromolar inhibitors of NADK1 from L. monocytogenes, including its most potent in vitro inhibitor reported so far (with a 300-fold improvement compared to NKI1).
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Affiliation(s)
- David A Clément
- Institut Pasteur, Université Paris Cité, CNRS UMR3523, Unité de Chimie et Biocatalyse, F-75015, Paris, France
| | - Muriel Gelin
- Centre de Biologie Structurale (CBS), CNRS UMR5048, INSERM U1054, Université de Montpellier, 34090, Montpellier, France
| | - Clarisse Leseigneur
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Unité de Recherche Yersinia, F-75015, Paris, France
| | - Valérie Huteau
- Institut Pasteur, Université Paris Cité, CNRS UMR3523, Unité de Chimie et Biocatalyse, F-75015, Paris, France
| | - Lou Mondange
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Unité de Recherche Yersinia, F-75015, Paris, France
| | - Jean-Luc Pons
- Centre de Biologie Structurale (CBS), CNRS UMR5048, INSERM U1054, Université de Montpellier, 34090, Montpellier, France
| | - Olivier Dussurget
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Unité de Recherche Yersinia, F-75015, Paris, France
| | - Corinne Lionne
- Centre de Biologie Structurale (CBS), CNRS UMR5048, INSERM U1054, Université de Montpellier, 34090, Montpellier, France
| | - Gilles Labesse
- Centre de Biologie Structurale (CBS), CNRS UMR5048, INSERM U1054, Université de Montpellier, 34090, Montpellier, France.
| | - Sylvie Pochet
- Institut Pasteur, Université Paris Cité, CNRS UMR3523, Unité de Chimie et Biocatalyse, F-75015, Paris, France.
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19
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Costa MDOCE, do Nascimento APB, Martins YC, dos Santos MT, Figueiredo AMDS, Perez-Rueda E, Nicolás MF. The gene regulatory network of Staphylococcus aureus ST239-SCC mecIII strain Bmb9393 and assessment of genes associated with the biofilm in diverse backgrounds. Front Microbiol 2023; 13:1049819. [PMID: 36704545 PMCID: PMC9871828 DOI: 10.3389/fmicb.2022.1049819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 12/19/2022] [Indexed: 01/12/2023] Open
Abstract
Introduction Staphylococcus aureus is one of the most prevalent and relevant pathogens responsible for a wide spectrum of hospital-associated or community-acquired infections. In addition, methicillin-resistant Staphylococcus aureus may display multidrug resistance profiles that complicate treatment and increase the mortality rate. The ability to produce biofilm, particularly in device-associated infections, promotes chronic and potentially more severe infections originating from the primary site. Understanding the complex mechanisms involved in planktonic and biofilm growth is critical to identifying regulatory connections and ways to overcome the global health problem of multidrug-resistant bacteria. Methods In this work, we apply literature-based and comparative genomics approaches to reconstruct the gene regulatory network of the high biofilm-producing strain Bmb9393, belonging to one of the highly disseminating successful clones, the Brazilian epidemic clone. To the best of our knowledge, we describe for the first time the topological properties and network motifs for the Staphylococcus aureus pathogen. We performed this analysis using the ST239-SCCmecIII Bmb9393 strain. In addition, we analyzed transcriptomes available in the literature to construct a set of genes differentially expressed in the biofilm, covering different stages of the biofilms and genetic backgrounds of the strains. Results and discussion The Bmb9393 gene regulatory network comprises 1,803 regulatory interactions between 64 transcription factors and the non-redundant set of 1,151 target genes with the inclusion of 19 new regulons compared to the N315 transcriptional regulatory network published in 2011. In the Bmb9393 network, we found 54 feed-forward loop motifs, where the most prevalent were coherent type 2 and incoherent type 2. The non-redundant set of differentially expressed genes in the biofilm consisted of 1,794 genes with functional categories relevant for adaptation to the variable microenvironments established throughout the biofilm formation process. Finally, we mapped the set of genes with altered expression in the biofilm in the Bmb9393 gene regulatory network to depict how different growth modes can alter the regulatory systems. The data revealed 45 transcription factors and 876 shared target genes. Thus, the gene regulatory network model provided represents the most up-to-date model for Staphylococcus aureus, and the set of genes altered in the biofilm provides a global view of their influence on biofilm formation from distinct experimental perspectives and different strain backgrounds.
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Affiliation(s)
| | - Ana Paula Barbosa do Nascimento
- Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, Brazil
| | | | | | - Agnes Marie de Sá Figueiredo
- Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas, Universidad Nacional Autónoma de México, Unidad Académica Yucatán, Merida, Mexico
| | - Ernesto Perez-Rueda
- Laboratório de Biologia Molecular de Bactérias, Instituto de Microbiologia Paulo de Goés, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil,*Correspondence: Ernesto Perez-Rueda ✉
| | - Marisa Fabiana Nicolás
- Laboratório Nacional de Computação Científica (LNCC), Petrópolis, Brazil,Marisa Fabiana Nicolás ✉
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20
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Spoto M, Riera Puma JP, Fleming E, Guan C, Ondouah Nzutchi Y, Kim D, Oh J. Large-Scale CRISPRi and Transcriptomics of Staphylococcus epidermidis Identify Genetic Factors Implicated in Lifestyle Versatility. mBio 2022; 13:e0263222. [PMID: 36409086 PMCID: PMC9765180 DOI: 10.1128/mbio.02632-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 10/27/2022] [Indexed: 11/23/2022] Open
Abstract
Staphylococcus epidermidis is a ubiquitous human commensal skin bacterium that is also one of the most prevalent nosocomial pathogens. The genetic factors underlying this remarkable lifestyle plasticity are incompletely understood, mainly due to the difficulties of genetic manipulation, precluding high-throughput functional profiling of this species. To probe the versatility of S. epidermidis to survive across a diversity of environmental conditions, we developed a large-scale CRISPR interference (CRISPRi) screen complemented by transcriptional profiling (RNA sequencing) across 24 diverse conditions and piloted a droplet-based CRISPRi approach to enhance throughput and sensitivity. We identified putative essential genes, importantly revealing amino acid metabolism as crucial to survival across diverse environments, and demonstrated the importance of trace metal uptake for survival under multiple stress conditions. We identified pathways significantly enriched and repressed across our range of stress and nutrient-limited conditions, demonstrating the considerable plasticity of S. epidermidis in responding to environmental stressors. Additionally, we postulate a mechanism by which nitrogen metabolism is linked to lifestyle versatility in response to hyperosmotic challenges, such as those encountered on human skin. Finally, we examined the survival of S. epidermidis under acid stress and hypothesize a role for cell wall modification as a vital component of the survival response under acidic conditions. Taken together, this study integrates large-scale CRISPRi and transcriptomics data across multiple environments to provide insights into a keystone member of the human skin microbiome. Our results additionally provide a valuable benchmarking analysis for CRISPRi screens and are a rich resource for other staphylococcal researchers. IMPORTANCE Staphylococcus epidermidis is a bacteria that broadly inhabits healthy human skin, yet it is also a common cause of skin infections and bloodstream infections associated with implanted medical devices. Because human skin has many different types of S. epidermidis, each containing different genes, our goal is to determine how these different genes allow S. epidermidis to switch from healthy growth in the skin to being an infectious pathogen. Understanding this switch is critical to developing new strategies to prevent and treat S. epidermidis infections.
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Affiliation(s)
- Michelle Spoto
- The Jackson Laboratory for Genomic Medicine, Farmington, Connecticut, USA
- The University of Connecticut Health Center, Farmington, Connecticut, USA
| | | | - Elizabeth Fleming
- The Jackson Laboratory for Genomic Medicine, Farmington, Connecticut, USA
| | - Changhui Guan
- The Jackson Laboratory for Genomic Medicine, Farmington, Connecticut, USA
| | | | - Dean Kim
- The Jackson Laboratory for Genomic Medicine, Farmington, Connecticut, USA
| | - Julia Oh
- The Jackson Laboratory for Genomic Medicine, Farmington, Connecticut, USA
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21
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Winterhalter C, Stevens D, Fenyk S, Pelliciari S, Marchand E, Soultanas P, Ilangovan A, Murray H. SirA inhibits the essential DnaA:DnaD interaction to block helicase recruitment during Bacillus subtilis sporulation. Nucleic Acids Res 2022; 51:4302-4321. [PMID: 36416272 DOI: 10.1093/nar/gkac1060] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 10/04/2022] [Accepted: 10/24/2022] [Indexed: 11/24/2022] Open
Abstract
Bidirectional DNA replication from a chromosome origin requires the asymmetric loading of two helicases, one for each replisome. Our understanding of the molecular mechanisms underpinning helicase loading at bacterial chromosome origins is incomplete. Here we report both positive and negative mechanisms for directing helicase recruitment in the model organism Bacillus subtilis. Systematic characterization of the essential initiation protein DnaD revealed distinct protein interfaces required for homo-oligomerization, interaction with the master initiator protein DnaA, and interaction with the helicase co-loader protein DnaB. Informed by these properties of DnaD, we went on to find that the developmentally expressed repressor of DNA replication initiation, SirA, blocks the interaction between DnaD and DnaA, thereby restricting helicase recruitment from the origin during sporulation to inhibit further initiation events. These results advance our understanding of the mechanisms underpinning DNA replication initiation in B. subtilis, as well as guiding the search for essential cellular activities to target for antimicrobial drug design.
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Affiliation(s)
- Charles Winterhalter
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Newcastle Upon Tyne NE2 4AX, UK
| | - Daniel Stevens
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Newcastle Upon Tyne NE2 4AX, UK
| | - Stepan Fenyk
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Newcastle Upon Tyne NE2 4AX, UK
| | - Simone Pelliciari
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Newcastle Upon Tyne NE2 4AX, UK
| | - Elie Marchand
- Research Unit in Biology of Microorganisms, Department of Biology, Université de Namur, Namur, Belgium
| | - Panos Soultanas
- Biodiscovery Institute, School of Chemistry, University of Nottingham, Nottingham NG7 2RD, UK
| | - Aravindan Ilangovan
- Blizard Institute, School of Biological and Behavioural Sciences, Queen Mary University of London, Newark street, London E1 2AT, UK
| | - Heath Murray
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Newcastle Upon Tyne NE2 4AX, UK
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22
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The Staphylococcus aureus cell division protein, DivIC, interacts with the cell wall and controls its biosynthesis. Commun Biol 2022; 5:1228. [DOI: 10.1038/s42003-022-04161-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 10/24/2022] [Indexed: 11/13/2022] Open
Abstract
AbstractBacterial cell division is a complex, dynamic process that requires multiple protein components to orchestrate its progression. Many division proteins are highly conserved across bacterial species alluding to a common, basic mechanism. Central to division is a transmembrane trimeric complex involving DivIB, DivIC and FtsL in Gram-positives. Here, we show a distinct, essential role for DivIC in division and survival of Staphylococcus aureus. DivIC spatially regulates peptidoglycan synthesis, and consequently cell wall architecture, by influencing the recruitment to the division septum of the major peptidoglycan synthetases PBP2 and FtsW. Both the function of DivIC and its recruitment to the division site depend on its extracellular domain, which interacts with the cell wall via binding to wall teichoic acids. DivIC facilitates the spatial and temporal coordination of peptidoglycan synthesis with the developing architecture of the septum during cell division. A better understanding of the cell division mechanisms in S. aureus and other pathogenic microorganisms can provide possibilities for the development of new, more effective treatments for bacterial infections.
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23
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Pederick JL, Horsfall AJ, Jovcevski B, Klose J, Abell AD, Pukala TL, Bruning JB. Discovery of an ʟ-amino acid ligase implicated in Staphylococcal sulfur amino acid metabolism. J Biol Chem 2022; 298:102392. [PMID: 35988643 PMCID: PMC9486568 DOI: 10.1016/j.jbc.2022.102392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 08/10/2022] [Accepted: 08/15/2022] [Indexed: 11/06/2022] Open
Abstract
Enzymes involved in Staphylococcus aureus amino acid metabolism have recently gained traction as promising targets for the development of new antibiotics, however, not all aspects of this process are understood. The ATP-grasp superfamily includes enzymes that predominantly catalyze the ATP-dependent ligation of various carboxylate and amine substrates. One subset, ʟ-amino acid ligases (LALs), primarily catalyze the formation of dipeptide products in Gram-positive bacteria, however, their involvement in S. aureus amino acid metabolism has not been investigated. Here, we present the characterization of the putative ATP-grasp enzyme (SAOUHSC_02373) from S. aureus NCTC 8325 and its identification as a novel LAL. First, we interrogated the activity of SAOUHSC_02373 against a panel of ʟ-amino acid substrates. As a result, we identified SAOUHSC_02373 as an LAL with high selectivity for ʟ-aspartate and ʟ-methionine substrates, specifically forming an ʟ-aspartyl–ʟ-methionine dipeptide. Thus, we propose that SAOUHSC_02373 be assigned as ʟ-aspartate–ʟ-methionine ligase (LdmS). To further understand this unique activity, we investigated the mechanism of LdmS by X-ray crystallography, molecular modeling, and site-directed mutagenesis. Our results suggest that LdmS shares a similar mechanism to other ATP-grasp enzymes but possesses a distinctive active site architecture that confers selectivity for the ʟ-Asp and ʟ-Met substrates. Phylogenetic analysis revealed LdmS homologs are highly conserved in Staphylococcus and closely related Gram-positive Firmicutes. Subsequent genetic analysis upstream of the ldmS operon revealed several trans-acting regulatory elements associated with control of Met and Cys metabolism. Together, these findings support a role for LdmS in Staphylococcal sulfur amino acid metabolism.
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Affiliation(s)
- Jordan L Pederick
- Institute for Photonics and Advanced Sensing, (IPAS), School of Biological Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Aimee J Horsfall
- Institute for Photonics and Advanced Sensing, (IPAS), School of Physical Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia; ARC Centre of Excellence for Nanoscale BioPhotonics (CNBP), Adelaide, South Australia 5005, Australia
| | - Blagojce Jovcevski
- Department of Chemistry, The University of Adelaide, Adelaide, South Australia 5005, Australia; School of Agriculture, Food and Wine, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Jack Klose
- Department of Chemistry, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Andrew D Abell
- Institute for Photonics and Advanced Sensing, (IPAS), School of Physical Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia; ARC Centre of Excellence for Nanoscale BioPhotonics (CNBP), Adelaide, South Australia 5005, Australia
| | - Tara L Pukala
- Department of Chemistry, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - John B Bruning
- Institute for Photonics and Advanced Sensing, (IPAS), School of Biological Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia.
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24
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Hotinger JA, Gallagher AH, May AE. Phage-Related Ribosomal Proteases (Prps): Discovery, Bioinformatics, and Structural Analysis. Antibiotics (Basel) 2022; 11:antibiotics11081109. [PMID: 36009978 PMCID: PMC9405229 DOI: 10.3390/antibiotics11081109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 08/08/2022] [Accepted: 08/11/2022] [Indexed: 11/16/2022] Open
Abstract
Many new antimicrobials are analogs of existing drugs, sharing the same targets and mechanisms of action. New antibiotic targets are critically needed to combat the growing threat of antimicrobial-resistant bacteria. Phage-related ribosomal proteases (Prps) are a recently structurally characterized antibiotic target found in pathogens such as Staphylococcus aureus, Clostridioides difficile, and Streptococcus pneumoniae. These bacteria encode an N-terminal extension on their ribosomal protein L27 that is not present in other bacteria. The cleavage of this N-terminal extension from L27 by Prp is necessary to create a functional ribosome. Thus, Prp inhibition may serve as an alternative to direct binding and inhibition of the ribosome. This bioinformatic and structural analysis covers the discovery, function, and structural characteristics of known Prps. This information will be helpful in future endeavors to design selective therapeutics targeting the Prps of important pathogens.
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25
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Finding New Fundamental Pieces for the Bacterial Cell Division Puzzle. mBio 2022; 13:e0073722. [PMID: 35735744 PMCID: PMC9426480 DOI: 10.1128/mbio.00737-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The division of bacterial cells into two daughter cells requires a precise balance of more than a dozen highly conserved proteins that coordinate chromosome segregation with the synthesis of the novel cell envelope. The paradigms of cell division were established in rod-shaped bacteria and this fundamental process is far less characterized in spherical bacteria. In a search for novel, essential cell division proteins in Staphylococci, Myrbråten et al. used combined depletion and subcellular localization analyses to identify the staphylococcal morphology determinant, SmdA, that is exclusively found in cocci. Knockdown of smdA results in severe division defects and increased sensitivity to cell wall targeting antibiotics. Although determining the precise role of SmdA in S. aureus cell division will require further research, this study provides a striking example of how researchers can assign functions to genes that are too fundamental to cell biology to allow genetic inactivation.
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26
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Hotinger JA, Pendergrass HA, Peterson D, Wright HT, May AE. Phage-Related Ribosomal Protease (Prp) of Staphylococcus aureus: In Vitro Michaelis-Menten Kinetics, Screening for Inhibitors, and Crystal Structure of a Covalent Inhibition Product Complex. Biochemistry 2022; 61:1323-1336. [PMID: 35731716 DOI: 10.1021/acs.biochem.2c00010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Phage-related ribosomal proteases (Prps) are essential for the assembly and maturation of the ribosome in Firmicutes, including the human pathogens Staphylococcus aureus, Streptococcus pneumoniae, and Clostridium difficile. These bacterial proteases cleave off an N-terminal extension of a precursor of ribosomal protein L27, a processing step that is essential for the formation of functional ribosomes. This essential role of Prp in these pathogens has identified this protease as a potential antibiotic target. In this work, we determine the X-ray crystal structure of a covalent inhibition complex at 2.35 Å resolution, giving the first complete picture of the active site of a functional Prp. We also characterize the kinetic activity and screen for potential inhibitors of Prp. This work gives the most complete characterization of the structure and specificity of this novel class of proteases to date.
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Affiliation(s)
- Julia A Hotinger
- Department of Medicinal Chemistry and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Heather A Pendergrass
- Department of Medicinal Chemistry and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Darrell Peterson
- Department of Medicinal Chemistry and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - H Tonie Wright
- Department of Medicinal Chemistry and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Aaron E May
- Department of Medicinal Chemistry and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia 23298, United States
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27
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Leseigneur C, Boucontet L, Duchateau M, Pizarro-Cerda J, Matondo M, Colucci-Guyon E, Dussurget O. NAD kinase promotes Staphylococcus aureus pathogenesis by supporting production of virulence factors and protective enzymes. eLife 2022; 11:79941. [PMID: 35723663 PMCID: PMC9208755 DOI: 10.7554/elife.79941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 05/30/2022] [Indexed: 11/13/2022] Open
Abstract
Nicotinamide adenine dinucleotide phosphate (NADPH) is the primary electron donor for reductive reactions that are essential for the biosynthesis of major cell components in all organisms. Nicotinamide adenine dinucleotide kinase (NADK) is the only enzyme that catalyzes the synthesis of NADP(H) from NAD(H). While the enzymatic properties and physiological functions of NADK have been thoroughly studied, the role of NADK in bacterial pathogenesis remains unknown. Here, we used CRISPR interference to knock down NADK gene expression to address the role of this enzyme in Staphylococcus aureus pathogenic potential. We find that NADK inhibition drastically decreases mortality of zebrafish infected with S. aureus. Furthermore, we show that NADK promotes S. aureus survival in infected macrophages by protecting bacteria from antimicrobial defense mechanisms. Proteome-wide data analysis revealed that production of major virulence-associated factors is sustained by NADK. We demonstrate that NADK is required for expression of the quorum-sensing response regulator AgrA, which controls critical S. aureus virulence determinants. These findings support a key role for NADK in bacteria survival within innate immune cells and the host during infection.
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Affiliation(s)
- Clarisse Leseigneur
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Unité de Recherche Yersinia, Paris, France
| | - Laurent Boucontet
- Institut Pasteur, Université Paris Cité, CNRS UMR3738, Unité Macrophages et Développement de l'Immunité, Paris, France
| | - Magalie Duchateau
- Institut Pasteur, Université Paris Cité, CNRS USR2000, Unité de Spectrométrie de Masse pour la Biologie, Plateforme de protéomique, Paris, France
| | - Javier Pizarro-Cerda
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Unité de Recherche Yersinia, Paris, France
| | - Mariette Matondo
- Institut Pasteur, Université Paris Cité, CNRS USR2000, Unité de Spectrométrie de Masse pour la Biologie, Plateforme de protéomique, Paris, France
| | - Emma Colucci-Guyon
- Institut Pasteur, Université Paris Cité, CNRS UMR3738, Unité Macrophages et Développement de l'Immunité, Paris, France
| | - Olivier Dussurget
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Unité de Recherche Yersinia, Paris, France
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28
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Wang M, Buist G, van Dijl JM. Staphylococcus aureus cell wall maintenance - the multifaceted roles of peptidoglycan hydrolases in bacterial growth, fitness, and virulence. FEMS Microbiol Rev 2022; 46:6604383. [PMID: 35675307 PMCID: PMC9616470 DOI: 10.1093/femsre/fuac025] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 04/22/2022] [Accepted: 05/25/2022] [Indexed: 01/07/2023] Open
Abstract
Staphylococcus aureus is an important human and livestock pathogen that is well-protected against environmental insults by a thick cell wall. Accordingly, the wall is a major target of present-day antimicrobial therapy. Unfortunately, S. aureus has mastered the art of antimicrobial resistance, as underscored by the global spread of methicillin-resistant S. aureus (MRSA). The major cell wall component is peptidoglycan. Importantly, the peptidoglycan network is not only vital for cell wall function, but it also represents a bacterial Achilles' heel. In particular, this network is continuously opened by no less than 18 different peptidoglycan hydrolases (PGHs) encoded by the S. aureus core genome, which facilitate bacterial growth and division. This focuses attention on the specific functions executed by these enzymes, their subcellular localization, their control at the transcriptional and post-transcriptional levels, their contributions to staphylococcal virulence and their overall importance in bacterial homeostasis. As highlighted in the present review, our understanding of the different aspects of PGH function in S. aureus has been substantially increased over recent years. This is important because it opens up new possibilities to exploit PGHs as innovative targets for next-generation antimicrobials, passive or active immunization strategies, or even to engineer them into effective antimicrobial agents.
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Affiliation(s)
- Min Wang
- Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, PO Box 30001, 9700 RB Groningen, the Netherlands
| | | | - Jan Maarten van Dijl
- Corresponding author: Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, P.O. box 30001, HPC EB80, 9700 RB Groningen, the Netherlands, Tel. +31-50-3615187; Fax. +31-50-3619105; E-mail:
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29
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Sweeney P, Galliford A, Kumar A, Raju D, Krishna NB, Sutherland E, Leo CJ, Fisher G, Lalitha R, Muthuraj L, Sigamani G, Oehler V, Synowsky S, Shirran SL, Gloster TM, Czekster CM, Kumar P, da Silva RG. Structure, dynamics, and molecular inhibition of the Staphylococcus aureus m 1A22-tRNA methyltransferase TrmK. J Biol Chem 2022; 298:102040. [PMID: 35595101 PMCID: PMC9190014 DOI: 10.1016/j.jbc.2022.102040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 05/02/2022] [Accepted: 05/04/2022] [Indexed: 11/29/2022] Open
Abstract
The enzyme m1A22-tRNA methyltransferase (TrmK) catalyzes the transfer of a methyl group to the N1 of adenine 22 in bacterial tRNAs. TrmK is essential for Staphylococcus aureus survival during infection but has no homolog in mammals, making it a promising target for antibiotic development. Here, we characterize the structure and function of S. aureus TrmK (SaTrmK) using X-ray crystallography, binding assays, and molecular dynamics simulations. We report crystal structures for the SaTrmK apoenzyme as well as in complexes with methyl donor SAM and co-product product SAH. Isothermal titration calorimetry showed that SAM binds to the enzyme with favorable but modest enthalpic and entropic contributions, whereas SAH binding leads to an entropic penalty compensated for by a large favorable enthalpic contribution. Molecular dynamics simulations point to specific motions of the C-terminal domain being altered by SAM binding, which might have implications for tRNA recruitment. In addition, activity assays for SaTrmK-catalyzed methylation of A22 mutants of tRNALeu demonstrate that the adenine at position 22 is absolutely essential. In silico screening of compounds suggested the multifunctional organic toxin plumbagin as a potential inhibitor of TrmK, which was confirmed by activity measurements. Furthermore, LC-MS data indicated the protein was covalently modified by one equivalent of the inhibitor, and proteolytic digestion coupled with LC-MS identified Cys92 in the vicinity of the SAM-binding site as the sole residue modified. These results identify a cryptic binding pocket of SaTrmK, laying a foundation for future structure-based drug discovery.
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Affiliation(s)
- Pamela Sweeney
- School of Biology, Biomedical Sciences Research Complex, University of St Andrews, St Andrews KY16 9ST, UK
| | - Ashleigh Galliford
- School of Biology, Biomedical Sciences Research Complex, University of St Andrews, St Andrews KY16 9ST, UK
| | | | - Dinesh Raju
- Kcat Enzymatic Private Limited, Bangalore, India
| | | | - Emmajay Sutherland
- School of Biology, Biomedical Sciences Research Complex, University of St Andrews, St Andrews KY16 9ST, UK
| | - Caitlin J Leo
- School of Biology, Biomedical Sciences Research Complex, University of St Andrews, St Andrews KY16 9ST, UK
| | - Gemma Fisher
- School of Biology, Biomedical Sciences Research Complex, University of St Andrews, St Andrews KY16 9ST, UK
| | | | | | | | - Verena Oehler
- School of Biology, Biomedical Sciences Research Complex, University of St Andrews, St Andrews KY16 9ST, UK
| | - Silvia Synowsky
- School of Biology, Biomedical Sciences Research Complex, University of St Andrews, St Andrews KY16 9ST, UK
| | - Sally L Shirran
- School of Biology, Biomedical Sciences Research Complex, University of St Andrews, St Andrews KY16 9ST, UK
| | - Tracey M Gloster
- School of Biology, Biomedical Sciences Research Complex, University of St Andrews, St Andrews KY16 9ST, UK
| | - Clarissa M Czekster
- School of Biology, Biomedical Sciences Research Complex, University of St Andrews, St Andrews KY16 9ST, UK
| | - Pravin Kumar
- Kcat Enzymatic Private Limited, Bangalore, India.
| | - Rafael G da Silva
- School of Biology, Biomedical Sciences Research Complex, University of St Andrews, St Andrews KY16 9ST, UK.
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30
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Naclerio GA, Abutaleb NS, Onyedibe KI, Karanja C, Eldesouky HE, Liang HW, Dieterly A, Aryal UK, Lyle T, Seleem MN, Sintim HO. Mechanistic Studies and In Vivo Efficacy of an Oxadiazole-Containing Antibiotic. J Med Chem 2022; 65:6612-6630. [PMID: 35482444 PMCID: PMC9124606 DOI: 10.1021/acs.jmedchem.1c02034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) infections are still difficult to treat, despite the availability of many FDA-approved antibiotics. Thus, new compound scaffolds are still needed to treat MRSA. The oxadiazole-containing compound, HSGN-94, has been shown to reduce lipoteichoic acid (LTA) in S. aureus, but the mechanism that accounts for LTA biosynthesis inhibition remains uncharacterized. Herein, we report the elucidation of the mechanism by which HSGN-94 inhibits LTA biosynthesis via utilization of global proteomics, activity-based protein profiling, and lipid analysis via multiple reaction monitoring (MRM). Our data suggest that HSGN-94 inhibits LTA biosynthesis via direct binding to PgcA and downregulation of PgsA. We further show that HSGN-94 reduces the MRSA load in skin infection (mouse) and decreases pro-inflammatory cytokines in MRSA-infected wounds. Collectively, HSGN-94 merits further consideration as a potential drug for staphylococcal infections.
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Affiliation(s)
- George A Naclerio
- Chemistry Department, Institute for Drug Discovery, Purdue University, West Lafayette, Indiana 47907, United States
| | - Nader S Abutaleb
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24060, United States
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, Indiana 47907, United States
| | - Kenneth I Onyedibe
- Chemistry Department, Institute for Drug Discovery, Purdue University, West Lafayette, Indiana 47907, United States
- Purdue Institute of Inflammation, Immunology, and Infectious Disease, Purdue University, West Lafayette, Indiana 47907, United States
| | - Caroline Karanja
- Chemistry Department, Institute for Drug Discovery, Purdue University, West Lafayette, Indiana 47907, United States
| | - Hassan E Eldesouky
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24060, United States
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, Indiana 47907, United States
| | - Hsin-Wen Liang
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24060, United States
| | - Alexandra Dieterly
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, Indiana 47907, United States
| | - Uma K Aryal
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, Indiana 47907, United States
- Purdue Proteomics Facility, Bindley Bioscience Center, Purdue University, West Lafayette, Indiana 47907, United States
| | - Tiffany Lyle
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, Indiana 47907, United States
- Center for Comparative Translational Research, Purdue University, West Lafayette, Indiana 47907, United States
| | - Mohamed N Seleem
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24060, United States
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, Indiana 47907, United States
- Center for Emerging, Zoonotic and Arthropod-borne Pathogens, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, United States
| | - Herman O Sintim
- Chemistry Department, Institute for Drug Discovery, Purdue University, West Lafayette, Indiana 47907, United States
- Purdue Institute of Inflammation, Immunology, and Infectious Disease, Purdue University, West Lafayette, Indiana 47907, United States
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31
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Hogan AM, Cardona ST. Gradients in gene essentiality reshape antibacterial research. FEMS Microbiol Rev 2022; 46:fuac005. [PMID: 35104846 PMCID: PMC9075587 DOI: 10.1093/femsre/fuac005] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 01/14/2022] [Accepted: 01/24/2022] [Indexed: 02/03/2023] Open
Abstract
Essential genes encode the processes that are necessary for life. Until recently, commonly applied binary classifications left no space between essential and non-essential genes. In this review, we frame bacterial gene essentiality in the context of genetic networks. We explore how the quantitative properties of gene essentiality are influenced by the nature of the encoded process, environmental conditions and genetic background, including a strain's distinct evolutionary history. The covered topics have important consequences for antibacterials, which inhibit essential processes. We argue that the quantitative properties of essentiality can thus be used to prioritize antibacterial cellular targets and desired spectrum of activity in specific infection settings. We summarize our points with a case study on the core essential genome of the cystic fibrosis pathobiome and highlight avenues for targeted antibacterial development.
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Affiliation(s)
- Andrew M Hogan
- Department of Microbiology, University of Manitoba, 45 Chancellor's Circle, Winnipeg, Manitoba R3T 2N2, Canada
| | - Silvia T Cardona
- Department of Microbiology, University of Manitoba, 45 Chancellor's Circle, Winnipeg, Manitoba R3T 2N2, Canada
- Department of Medical Microbiology and Infectious Diseases, Max Rady College of Medicine, University of Manitoba, Room 543 - 745 Bannatyne Avenue, Winnipeg, Manitoba, R3E 0J9, Canada
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32
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Shang Y, Guo J, Zhao Y, Chen J, Meng Q, Qu D, Zheng J, Yu Z, Wu Y, Deng Q. Clemastine Inhibits the Biofilm and Hemolytic of Staphylococcus aureus through the GdpP Protein. Microbiol Spectr 2022; 10:e0054121. [PMID: 35234502 PMCID: PMC8941875 DOI: 10.1128/spectrum.00541-21] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 12/16/2021] [Indexed: 11/28/2022] Open
Abstract
Staphylococcus aureus poses a significant threat to human health due to its virulence and multidrug resistance. In addition, recalcitrant biofilm formation of S. aureus often results in chronic infection and the treatment tolerance toward the traditional antibiotics. Thus, the development of novel antimicrobial agents capable to inhibit or eradicate S. aureus biofilm formation does matter. Here, we demonstrated that clemastine showed slight bacteriostatic activity and enhanced the antibacterial activity of oxacillin against S. aureus. Moreover, the dramatic inhibition of biofilm formation was found in clinical S. aureus strains by clemastine. Clemastine inhibited the release of eDNA during the biofilm formation and decreased the S. aureus hemolytic activity. Moreover, the S. aureus SA113 treated with clemastine displayed the decreased transcriptional level of the biofilm formation relevant genes (fnbB, icaA, and icaB), virulence genes (hlg, hld, lukde, lukpvl, beta-PSM, delta-PSM, and cap5A), and the regulatory genes agrA. The proteomics analysis of SA113 treated with clemastine demonstrated the significant changes in levels of biofilm-related proteins (stress response regulators ClpB and GroS, ATP-binding proteins, and urease metabolism), virulence-related proteins (SspA, superantigen, and VWbp), and methicillin resistance-related proteins (glutamine metabolism). The genetic mutations on gdpP (cyclic di-AMP phosphodiesterase) were found in the clemastine-induced tolerant derivative isolate by whole-genome sequencing. Furthermore, the interaction between clemastine and GdpP protein was demonstrated by the molecular docking, gdpP overexpression experiment, and thermal stability assay. Conclusively, clemastine might exert its inhibitory effects against the biofilm formation and hemolysis in S. aureus through targeting GdpP protein. IMPORTANCE The biofilm formation, which protects bacteria from stresses, including antibiotics and host immune responses, can be commonly found in clinical S. aureus isolates worldwide. Treatment failure of traditional antibiotics in biofilm-associated S. aureus infections remains a serious challenge. The novel anti-biofilm drug is urgently needed to address the looming crisis. In this study, clemastine, which is a histamine receptor H1 (HRH1) antagonist, was found to have a novel role of the significant inhibition against the biofilm formation and hemolytic activity of S. aureus and enhanced antibacterial activity against S. aureus when used in combination with oxacillin by targeting the GdpP protein. The discovery of this study identified novel use and mechanism of action of clemastine as a potential anti-biofilm drug for clinical application for S. aureus infectious.
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Affiliation(s)
- Yongpeng Shang
- Department of Infectious Diseases and the Key Lab of Endogenous Infection, Shenzhen Nanshan People's Hospital, the 6th Affiliated Hospital of Shenzhen University Health Science Center, Shenzhen, China
- National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, School of Medicine, Shenzhen University, Shenzhen, China
| | - Jie Guo
- Department of Infectious Diseases and the Key Lab of Endogenous Infection, Shenzhen Nanshan People's Hospital, the 6th Affiliated Hospital of Shenzhen University Health Science Center, Shenzhen, China
| | - Yuxi Zhao
- Department of Infectious Diseases and the Key Lab of Endogenous Infection, Shenzhen Nanshan People's Hospital, the 6th Affiliated Hospital of Shenzhen University Health Science Center, Shenzhen, China
| | - Junwen Chen
- Department of Infectious Diseases and the Key Lab of Endogenous Infection, Shenzhen Nanshan People's Hospital, the 6th Affiliated Hospital of Shenzhen University Health Science Center, Shenzhen, China
| | - Qingyin Meng
- Department of Infectious Diseases and the Key Lab of Endogenous Infection, Shenzhen Nanshan People's Hospital, the 6th Affiliated Hospital of Shenzhen University Health Science Center, Shenzhen, China
| | - Di Qu
- Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, School of Basic Medical Science and Institutes of Biomedical Sciences, Shanghai Medical College of Fudan University, Shanghai, China
| | - Jinxin Zheng
- Department of Infectious Diseases and the Key Lab of Endogenous Infection, Shenzhen Nanshan People's Hospital, the 6th Affiliated Hospital of Shenzhen University Health Science Center, Shenzhen, China
| | - Zhijian Yu
- Department of Infectious Diseases and the Key Lab of Endogenous Infection, Shenzhen Nanshan People's Hospital, the 6th Affiliated Hospital of Shenzhen University Health Science Center, Shenzhen, China
| | - Yang Wu
- Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, School of Basic Medical Science and Institutes of Biomedical Sciences, Shanghai Medical College of Fudan University, Shanghai, China
| | - Qiwen Deng
- Department of Infectious Diseases and the Key Lab of Endogenous Infection, Shenzhen Nanshan People's Hospital, the 6th Affiliated Hospital of Shenzhen University Health Science Center, Shenzhen, China
- National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, School of Medicine, Shenzhen University, Shenzhen, China
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33
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Ong ZX, Kannan B, Becker DL. Exploiting transposons in the study of Staphylococcus aureus pathogenesis and virulence. Crit Rev Microbiol 2022; 49:297-317. [PMID: 35438613 DOI: 10.1080/1040841x.2022.2052794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The opportunistic pathogen Staphylococcus aureus has an extremely complex relationship with humans. While the bacteria can exist as a commensal in many, it can cause a wide range of diseases and infections when turned pathogenic. Its presence is a determinant of chronicity and poor prognosis in numerous diseases, and its genomic plasticity causes S. aureus antimicrobial resistance to be one of the most dire contemporary medical problems to solve. Genetic manipulation of S. aureus has led to numerous findings that are vital in the fight against its pathogenesis. The utilisation of transposon mutant libraries for the systematic inspection of the S. aureus genome led to many landmark discoveries pertaining to the bacteria's pathogenicity, antimicrobial resistance acquisition, and virulence regulation. In this review, we describe mutant libraries, and their significant contributions, from various S. aureus strains created with commonly used transposons. The general workflow for the construction of libraries will be presented, along with a discussion of the challenges of undertaking the task of large-scale library construction. As the accessibility of transposon mutant library construction, screening, and analysis increases, this genetic tool could be further exploited in the study of the S. aureus genome.
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Affiliation(s)
- Zi Xin Ong
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.,Skin Research Institute, Singapore.,Nanyang Institute of Technology in Health and Medicine, Interdisciplinary Graduate Programme, Nanyang Technological University, Singapore
| | - Bavani Kannan
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.,Skin Research Institute, Singapore
| | - David L Becker
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.,Skin Research Institute, Singapore
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34
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Naclerio GA, Onyedibe KI, Karanja CW, Aryal UK, Sintim HO. Comparative Studies to Uncover Mechanisms of Action of N-(1,3,4-Oxadiazol-2-yl)benzamide Containing Antibacterial Agents. ACS Infect Dis 2022; 8:865-877. [PMID: 35297603 PMCID: PMC9188027 DOI: 10.1021/acsinfecdis.1c00613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Drug-resistant bacterial pathogens still cause high levels of mortality annually despite the availability of many antibiotics. Methicillin-resistant Staphylococcus aureus (MRSA) is especially problematic, and the rise in resistance to front-line treatments like vancomycin and linezolid calls for new chemical modalities to treat chronic and relapsing MRSA infections. Halogenated N-(1,3,4-oxadiazol-2-yl)benzamides are an interesting class of antimicrobial agents, which have been described by multiple groups to be effective against different bacterial pathogens. The modes of action of a few N-(1,3,4-oxadiazol-2-yl)benzamides have been elucidated. For example, oxadiazoles KKL-35 and MBX-4132 have been described as inhibitors of trans-translation (a ribosome rescue pathway), while HSGN-94 was shown to inhibit lipoteichoic acid (LTA). However, other similarly halogenated N-(1,3,4-oxadiazol-2-yl)benzamides neither inhibit trans-translation nor LTA biosynthesis but are potent antimicrobial agents. For example, HSGN-220, -218, and -144 are N-(1,3,4-oxadiazol-2-yl)benzamides that are modified with OCF3, SCF3, or SF5 and have remarkable minimum inhibitory concentrations ranging from 1 to 0.06 μg/mL against MRSA clinical isolates and show a low propensity to develop resistance to MRSA over 30 days. The mechanism of action of these highly potent oxadiazoles is however unknown. To provide insights into how these halogenated N-(1,3,4-oxadiazol-2-yl)benzamides inhibit bacterial growth, we performed global proteomics and RNA expression analysis of some essential genes of S. aureus treated with HSGN-220, -218, and -144. These studies revealed that the oxadiazoles HSGN-220, -218, and -144 are multitargeting antibiotics that regulate menaquinone biosynthesis and other essential proteins like DnaX, Pol IIIC, BirA, LexA, and DnaC. In addition, these halogenated N-(1,3,4-oxadiazol-2-yl)benzamides were able to depolarize bacterial membranes and regulate siderophore biosynthesis and heme regulation. Iron starvation appears to be part of the mechanism of action that led to bacterial killing. This study demonstrates that N-(1,3,4-oxadiazol-2-yl)benzamides are indeed privileged scaffolds for the development of antibacterial agents and that subtle modifications lead to changes to the mechanism of action.
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Affiliation(s)
- George A. Naclerio
- Chemistry Department, Institute for Drug Discovery, Purdue University, West Lafayette, Indiana 47907, United States
| | - Kenneth I. Onyedibe
- Chemistry Department, Institute for Drug Discovery, Purdue University, West Lafayette, Indiana 47907, United States
- Purdue Institute for Inflammation, Immunology, and Infectious Diseases, West Lafayette, Indiana 47907, United States
| | - Caroline W. Karanja
- Chemistry Department, Institute for Drug Discovery, Purdue University, West Lafayette, Indiana 47907, United States
| | - Uma K. Aryal
- Department of Comparative Pathobiology, Purdue University, West Lafayette, Indiana 47907, United States
- Purdue Proteomics Facility, Bindley Bioscience Center, Purdue University, West Lafayette, Indiana 47907, United States
| | - Herman O. Sintim
- Chemistry Department, Institute for Drug Discovery, Purdue University, West Lafayette, Indiana 47907, United States
- Purdue Institute for Inflammation, Immunology, and Infectious Diseases, West Lafayette, Indiana 47907, United States
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35
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Abstract
Cell division and cell wall synthesis in staphylococci need to be precisely coordinated and controlled to allow the cell to multiply while maintaining its nearly spherical shape. The mechanisms ensuring correct placement of the division plane and synthesis of new cell wall have been studied intensively. However, hitherto unknown factors and proteins are likely to play key roles in this complex interplay. Here, we identified and investigated a protein with a major influence on cell morphology in Staphylococcus aureus. The protein, named SmdA (for staphylococcal morphology determinant A), is a membrane protein with septum-enriched localization. By CRISPRi knockdown and overexpression combined with different microscopy techniques, we demonstrated that proper levels of SmdA were necessary for cell division, including septum formation and cell splitting. We also identified conserved residues in SmdA that were critical for its functionality. Pulldown and bacterial two-hybrid interaction experiments showed that SmdA interacted with several known cell division and cell wall synthesis proteins, including penicillin-binding proteins (PBPs) and EzrA. Notably, SmdA also affected susceptibility to cell wall targeting antibiotics, particularly in methicillin-resistant S. aureus (MRSA). Together, our results showed that S. aureus was dependent on balanced amounts of membrane attached SmdA to carry out proper cell division.
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36
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Muscato J, Morris HG, Mychack A, Rajagopal M, Baidin V, Hesser AR, Lee W, İnecik K, Wilson LJ, Kraml CM, Meredith TC, Walker S. Rapid Inhibitor Discovery by Exploiting Synthetic Lethality. J Am Chem Soc 2022; 144:3696-3705. [PMID: 35170959 PMCID: PMC9012225 DOI: 10.1021/jacs.1c12697] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Synthetic lethality occurs when inactivation of two genes is lethal but inactivation of either single gene is not. This phenomenon provides an opportunity for efficient compound discovery. Using differential growth screens, one can identify biologically active compounds that selectively inhibit proteins within the synthetic lethal network of any inactivated gene. Here, based purely on synthetic lethalities, we identified two compounds as the only possible inhibitors of Staphylococcus aureus lipoteichoic acid (LTA) biosynthesis from a screen of ∼230,000 compounds. Both compounds proved to inhibit the glycosyltransferase UgtP, which assembles the LTA glycolipid anchor. UgtP is required for β-lactam resistance in methicillin-resistant S. aureus (MRSA), and the inhibitors restored sensitivity to oxacillin in a highly resistant S. aureus strain. As no other compounds were pursued as possible LTA glycolipid assembly inhibitors, this work demonstrates the extraordinary efficiency of screens that exploit synthetic lethality to discover compounds that target specified pathways. The general approach should be applicable not only to other bacteria but also to eukaryotic cells.
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Affiliation(s)
- Jacob
D. Muscato
- Department
of Microbiology, Harvard University, 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Heidi G. Morris
- Department
of Microbiology, Harvard University, 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Aaron Mychack
- Department
of Microbiology, Harvard University, 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Mithila Rajagopal
- Department
of Microbiology, Harvard University, 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States,Department
of Chemistry and Chemical Biology, Harvard
University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Vadim Baidin
- Department
of Chemistry and Chemical Biology, Harvard
University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Anthony R. Hesser
- Department
of Microbiology, Harvard University, 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Wonsik Lee
- Department
of Microbiology, Harvard University, 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Kemal İnecik
- Department
of Microbiology, Harvard University, 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Laura J. Wilson
- Lotus
Separations LLC, B20 Frick Chemistry Laboratory, Princeton, New Jersey 08544, United States
| | - Christina M. Kraml
- Lotus
Separations LLC, B20 Frick Chemistry Laboratory, Princeton, New Jersey 08544, United States
| | - Timothy C. Meredith
- Department
of Microbiology, Harvard University, 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Suzanne Walker
- Department
of Microbiology, Harvard University, 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States,Department
of Chemistry and Chemical Biology, Harvard
University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States,
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37
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Sivinski J, Ngo D, Zerio CJ, Ambrose AJ, Watson ER, Kaneko LK, Kostelic MM, Stevens M, Ray AM, Park Y, Wu C, Marty MT, Hoang QQ, Zhang DD, Lander GC, Johnson SM, Chapman E. Allosteric differences dictate GroEL complementation of E. coli. FASEB J 2022; 36:e22198. [PMID: 35199390 PMCID: PMC8887798 DOI: 10.1096/fj.202101708rr] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 01/22/2022] [Accepted: 01/25/2022] [Indexed: 11/11/2022]
Abstract
GroES/GroEL is the only bacterial chaperone essential under all conditions, making it a potential antibiotic target. Rationally targeting ESKAPE GroES/GroEL as an antibiotic strategy necessitates studying their structure and function. Herein, we outline the structural similarities between Escherichia coli and ESKAPE GroES/GroEL and identify significant differences in intra- and inter-ring cooperativity, required in the refolding cycle of client polypeptides. Previously, we observed that one-half of ESKAPE GroES/GroEL family members could not support cell viability when each was individually expressed in GroES/GroEL-deficient E. coli cells. Cell viability was found to be dependent on the allosteric compatibility between ESKAPE and E. coli subunits within mixed (E. coli and ESKAPE) tetradecameric GroEL complexes. Interestingly, differences in allostery did not necessarily result in differences in refolding rate for a given homotetradecameric chaperonin. Characterization of ESKAPE GroEL allostery, ATPase, and refolding rates in this study will serve to inform future studies focused on inhibitor design and mechanism of action studies.
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Affiliation(s)
- Jared Sivinski
- The University of Arizona, College of Pharmacy, Department
of Pharmacology and Toxicology, 1703 E. Mabel St., PO Box 210207, Tucson, AZ
85721
| | - Duc Ngo
- The University of Arizona, College of Pharmacy, Department
of Pharmacology and Toxicology, 1703 E. Mabel St., PO Box 210207, Tucson, AZ
85721
| | - Christopher J. Zerio
- The University of Arizona, College of Pharmacy, Department
of Pharmacology and Toxicology, 1703 E. Mabel St., PO Box 210207, Tucson, AZ
85721
| | - Andrew J. Ambrose
- The University of Arizona, College of Pharmacy, Department
of Pharmacology and Toxicology, 1703 E. Mabel St., PO Box 210207, Tucson, AZ
85721
| | - Edmond R. Watson
- Department of Integrative Structural and Computational
Biology, Scripps Research, La Jolla, CA, USA
| | - Lynn K. Kaneko
- The University of Arizona, College of Pharmacy, Department
of Pharmacology and Toxicology, 1703 E. Mabel St., PO Box 210207, Tucson, AZ
85721
| | - Marius M. Kostelic
- The University of Arizona, Department of Chemistry and
Biochemistry, Tucson, AZ 85721
| | - Mckayla Stevens
- Indiana University School of Medicine, Department of
Biochemistry and Molecular Biology, 635 Barnhill Dr., Indianapolis, IN 46202
| | - Anne-Marie Ray
- Indiana University School of Medicine, Department of
Biochemistry and Molecular Biology, 635 Barnhill Dr., Indianapolis, IN 46202
| | - Yangshin Park
- Indiana University School of Medicine, Department of
Biochemistry and Molecular Biology, 635 Barnhill Dr., Indianapolis, IN 46202,Stark Neurosciences Research Institute, Indiana University
School of Medicine. 320 W. 15th Street, Suite 414, Indianapolis, IN 46202,Department of Neurology, Indiana University School of
Medicine. 635 Barnhill Drive, Indianapolis, IN 46202
| | - Chunxiang Wu
- Department of Molecular Biophysics and Biochemistry, Yale
University, New Haven, CT 06520
| | - Michael T. Marty
- The University of Arizona, Department of Chemistry and
Biochemistry, Tucson, AZ 85721
| | - Quyen Q. Hoang
- Indiana University School of Medicine, Department of
Biochemistry and Molecular Biology, 635 Barnhill Dr., Indianapolis, IN 46202,Stark Neurosciences Research Institute, Indiana University
School of Medicine. 320 W. 15th Street, Suite 414, Indianapolis, IN 46202,Department of Neurology, Indiana University School of
Medicine. 635 Barnhill Drive, Indianapolis, IN 46202
| | - Donna D. Zhang
- The University of Arizona, College of Pharmacy, Department
of Pharmacology and Toxicology, 1703 E. Mabel St., PO Box 210207, Tucson, AZ
85721
| | - Gabriel C. Lander
- Department of Integrative Structural and Computational
Biology, Scripps Research, La Jolla, CA, USA
| | - Steven M. Johnson
- Indiana University School of Medicine, Department of
Biochemistry and Molecular Biology, 635 Barnhill Dr., Indianapolis, IN 46202
| | - Eli Chapman
- The University of Arizona, College of Pharmacy, Department
of Pharmacology and Toxicology, 1703 E. Mabel St., PO Box 210207, Tucson, AZ
85721,Corresponding author
, Phone: 520-626-2741
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38
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Schmidt C, Zollo M, Bonsignore R, Casini A, Hacker S. Competitive Profiling of Ligandable Cysteines in Staphylococcus aureus with an Organogold Compound. Chem Commun (Camb) 2022; 58:5526-5529. [DOI: 10.1039/d2cc01259f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
With the idea of exploiting metal templated C–S bond forming reactions to achieve modification of cysteines in bacterial proteins, a cyclometalated Au(III) compound was explored in a competitive chemoproteomic approach...
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39
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Bossé JT, Li Y, Leanse LG, Zhou L, Chaudhuri RR, Peters SE, Wang J, Maglennon GA, Holden MTG, Maskell DJ, Tucker AW, Wren BW, Rycroft AN, Langford PR. Rationally designed mariner vectors for functional genomic analysis of Actinobacillus pleuropneumoniae and other Pasteurellaceae species by transposon-directed insertion-site sequencing (TraDIS). ANIMAL DISEASES 2021; 1:29. [PMID: 34870287 PMCID: PMC8616859 DOI: 10.1186/s44149-021-00026-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 09/14/2021] [Indexed: 11/26/2022] Open
Abstract
Comprehensive identification of conditionally essential genes requires efficient tools for generating high-density transposon libraries that, ideally, can be analysed using next-generation sequencing methods such as Transposon Directed Insertion-site Sequencing (TraDIS). The Himar1 (mariner) transposon is ideal for generating near-saturating mutant libraries, especially in AT-rich chromosomes, as the requirement for integration is a TA dinucleotide, and this transposon has been used for mutagenesis of a wide variety of bacteria. However, plasmids for mariner delivery do not necessarily work well in all bacteria. In particular, there are limited tools for functional genomic analysis of Pasteurellaceae species of major veterinary importance, such as swine and cattle pathogens, Actinobacillus pleuropneumoniae and Pasteurella multocida, respectively. Here, we developed plasmids, pTsodCPC9 and pTlacPC9 (differing only in the promoter driving expression of the transposase gene), that allow delivery of mariner into both these pathogens, but which should also be applicable to a wider range of bacteria. Using the pTlacPC9 vector, we have generated, for the first time, saturating mariner mutant libraries in both A. pleuropneumoniae and P. multocida that showed a near random distribution of insertions around the respective chromosomes as detected by TraDIS. A preliminary screen of 5000 mutants each identified 8 and 14 genes, respectively, that are required for growth under anaerobic conditions. Future high-throughput screening of the generated libraries will facilitate identification of mutants required for growth under different conditions, including in vivo, highlighting key virulence factors and pathways that can be exploited for development of novel therapeutics and vaccines.
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Affiliation(s)
- Janine T Bossé
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, St. Mary's Campus, London, UK
| | - Yanwen Li
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, St. Mary's Campus, London, UK
| | - Leon G Leanse
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, St. Mary's Campus, London, UK.,Present Address: Wellman Center for Photomedicine, Harvard Medical School, Boston, USA
| | - Liqing Zhou
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, St. Mary's Campus, London, UK.,Present Address: The Applied Diagnostic Research and Evaluation Unit, St George's University of London, London, UK
| | - Roy R Chaudhuri
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK.,Present Address: Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK
| | - Sarah E Peters
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - Jinhong Wang
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - Gareth A Maglennon
- Department of Pathology and Pathogen Biology, The Royal Veterinary College, Hatfield, UK
| | - Matthew T G Holden
- The Wellcome Trust Sanger Institute, Cambridge, UK.,Present Address: School of Medicine, University of St Andrews, St Andrews, UK
| | - Duncan J Maskell
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK.,Present Address: The University of Melbourne, Parkville, Victoria Australia
| | - Alexander W Tucker
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - Brendan W Wren
- Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK
| | - Andrew N Rycroft
- Department of Pathology and Pathogen Biology, The Royal Veterinary College, Hatfield, UK
| | - Paul R Langford
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, St. Mary's Campus, London, UK
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40
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Freire V, Lattanzio G, Orera I, Mañas P, Cebrián G. Component release after exposure of Staphylococcus aureus cells to pulsed electric fields. INNOV FOOD SCI EMERG 2021. [DOI: 10.1016/j.ifset.2021.102838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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41
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Bekaert M, Goffin N, McMillan S, Desbois AP. Essential Genes of Vibrio anguillarum and Other Vibrio spp. Guide the Development of New Drugs and Vaccines. Front Microbiol 2021; 12:755801. [PMID: 34745063 PMCID: PMC8564382 DOI: 10.3389/fmicb.2021.755801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 09/24/2021] [Indexed: 01/04/2023] Open
Abstract
Essential genes in bacterial pathogens are potential drug targets and vaccine candidates because disrupting their function is lethal. The development of new antibiotics, in addition to effective prevention measures such as vaccination, contributes to addressing the global problem of bacterial antibiotic resistance. The aim of this present study was to determine the essential genes of Vibrio anguillarum, a bacterial pathogen of aquatic animals, as a means to identify putative targets for novel drugs and to assist the prioritisation of potential vaccine candidates. Essential genes were characterised by a Tn-seq approach using the TnSC189 mariner transposon to construct a library of 52,662 insertion mutants. In total, 329 essential genes were identified, with 34.7% found within the core genome of this species; each of these genes represents a strong potential drug target. Seven essential gene products were predicted to reside in the cell membrane or be released extracellularly, thus serving as putative vaccine candidates. Comparison to essential gene data from five other studies of Vibrio species revealed 13 proteins to be conserved across the studies, while 25 genes were specific to V. anguillarum and not found to be essential in the other Vibrio spp. This study provides new information on the essential genes of Vibrio species and the methodology may be applied to other pathogens to guide the development of new drugs and vaccines, which will assist efforts to counter antibiotic resistance.
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Affiliation(s)
- Michaël Bekaert
- Institute of Aquaculture, Faculty of Natural Sciences, University of Stirling, Stirling, United Kingdom
| | - Nikki Goffin
- Institute of Aquaculture, Faculty of Natural Sciences, University of Stirling, Stirling, United Kingdom
| | - Stuart McMillan
- Institute of Aquaculture, Faculty of Natural Sciences, University of Stirling, Stirling, United Kingdom
| | - Andrew P Desbois
- Institute of Aquaculture, Faculty of Natural Sciences, University of Stirling, Stirling, United Kingdom
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42
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Bandera AM, Bartho J, Lammens K, Drexler DJ, Kleinschwärzer J, Hopfner KP, Witte G. BusR senses bipartite DNA binding motifs by a unique molecular ruler architecture. Nucleic Acids Res 2021; 49:10166-10177. [PMID: 34432045 PMCID: PMC8517857 DOI: 10.1093/nar/gkab736] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 07/27/2021] [Accepted: 08/12/2021] [Indexed: 12/18/2022] Open
Abstract
The cyclic dinucleotide second messenger c-di-AMP is a major player in regulation of potassium homeostasis and osmolyte transport in a variety of bacteria. Along with various direct interactions with proteins such as potassium channels, the second messenger also specifically binds to transcription factors, thereby altering the processes in the cell on the transcriptional level. We here describe the structural and biochemical characterization of BusR from the human pathogen Streptococcus agalactiae. BusR is a member of a yet structurally uncharacterized subfamily of the GntR family of transcription factors that downregulates transcription of the genes for the BusA (OpuA) glycine-betaine transporter upon c-di-AMP binding. We report crystal structures of full-length BusR, its apo and c-di-AMP bound effector domain, as well as cryo-EM structures of BusR bound to its operator DNA. Our structural data, supported by biochemical and biophysical data, reveal that BusR utilizes a unique domain assembly with a tetrameric coiled-coil in between the binding platforms, serving as a molecular ruler to specifically recognize a 22 bp separated bipartite binding motif. Binding of c-di-AMP to BusR induces a shift in equilibrium from an inactivated towards an activated state that allows BusR to bind the target DNA, leading to transcriptional repression.
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Affiliation(s)
- Adrian M Bandera
- Gene Center, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, D-81377 München, Germany.,Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, D-81377 München, Germany
| | - Joseph Bartho
- Gene Center, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, D-81377 München, Germany.,Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, D-81377 München, Germany
| | - Katja Lammens
- Gene Center, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, D-81377 München, Germany.,Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, D-81377 München, Germany
| | - David Jan Drexler
- Gene Center, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, D-81377 München, Germany.,Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, D-81377 München, Germany
| | - Jasmin Kleinschwärzer
- Gene Center, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, D-81377 München, Germany.,Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, D-81377 München, Germany
| | - Karl-Peter Hopfner
- Gene Center, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, D-81377 München, Germany.,Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, D-81377 München, Germany
| | - Gregor Witte
- Gene Center, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, D-81377 München, Germany.,Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, D-81377 München, Germany
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43
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Verma D, Gupta V. New insights into the structure and function of an emerging drug target CysE. 3 Biotech 2021; 11:373. [PMID: 34367865 DOI: 10.1007/s13205-021-02891-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 06/09/2021] [Indexed: 11/24/2022] Open
Abstract
The antimicrobial resistant strains of several pathogens are major culprits of hospital-acquired nosocomial infections. An active and urgent action is necessary against these pathogens for the development of unique therapeutics. The cysteine biosynthetic pathway or genes (that are absent in humans) involved in the production of L-cysteine appear to be an attractive target for developing novel antibiotics. CysE, a Serine Acetyltransferase (SAT), catalyzes the first step of cysteine synthesis and is reported to be essential for the survival of persistence in several microbes including Mycobacterium tuberculosis. Structure determination provides fundamental insight into structure and function of protein and aid in drug design/discovery efforts. This review focuses on the overview of current knowledge of structure function, regulatory mechanism, and potential inhibitors (active site as well as allosteric site) of CysE. Despite having conserved structure, slight modification in CysE structure lead to altered the regulatory mechanism and hence affects the cysteine production. Due to its possible role in virulence and vital metabolism of pathogens makes it a potential target in the quest to develop novel therapeutics to treat multi-drug-resistant bacteria.
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Affiliation(s)
- Deepali Verma
- Department of Biotechnology, Jaypee Institute of Information Technology, A-10, Sector-62, Noida, Uttar Pradesh 201309 India
| | - Vibha Gupta
- Department of Biotechnology, Jaypee Institute of Information Technology, A-10, Sector-62, Noida, Uttar Pradesh 201309 India
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Labana P, Dornan MH, Lafrenière M, Czarny TL, Brown ED, Pezacki JP, Boddy CN. Armeniaspirols inhibit the AAA+ proteases ClpXP and ClpYQ leading to cell division arrest in Gram-positive bacteria. Cell Chem Biol 2021; 28:1703-1715.e11. [PMID: 34293284 DOI: 10.1016/j.chembiol.2021.07.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 04/22/2021] [Accepted: 06/29/2021] [Indexed: 01/16/2023]
Abstract
Multi-drug-resistant bacteria present an urgent threat to modern medicine, creating a desperate need for antibiotics with new modes of action. As natural products remain an unsurpassed source for clinically viable antibiotic compounds, we investigate the mechanism of action of armeniaspirol. The armeniaspirols are a structurally unique class of Gram-positive antibiotic discovered from Streptomyces armeniacus for which resistance cannot be readily obtained. We show that armeniaspirol inhibits the ATP-dependent proteases ClpXP and ClpYQ in vitro and in the model Gram-positive Bacillus subtilis. This inhibition dysregulates the divisome and elongasome supported by an upregulation of key proteins FtsZ, DivIVA, and MreB inducing cell division arrest. The inhibition of ClpXP and ClpYQ to dysregulate cell division represents a unique antibiotic mechanism of action and armeniaspirol is the only known natural product inhibitor of the coveted anti-virulence target ClpP. Thus, armeniaspirol possesses a promising lead scaffold for antibiotic development with unique pharmacology.
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Affiliation(s)
- Puneet Labana
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Mark H Dornan
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Matthew Lafrenière
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Tomasz L Czarny
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4K1, Canada
| | - Eric D Brown
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4K1, Canada
| | - John P Pezacki
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Christopher N Boddy
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, ON K1N 6N5, Canada.
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45
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Nlebedim VU, Chaudhuri RR, Walters K. Probabilistic Identification of Bacterial Essential Genes via insertion density using TraDIS Data with Tn5 libraries. Bioinformatics 2021; 37:4343-4349. [PMID: 34255819 PMCID: PMC8652038 DOI: 10.1093/bioinformatics/btab508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 06/24/2021] [Accepted: 07/23/2021] [Indexed: 11/29/2022] Open
Abstract
Motivation Probabilistic Identification of bacterial essential genes using transposon-directed insertion-site sequencing (TraDIS) data based on Tn5 libraries has received relatively little attention in the literature; most methods are designed for mariner transposon insertions. Analysis of Tn5 transposon-based genomic data is challenging due to the high insertion density and genomic resolution. We present a novel probabilistic Bayesian approach for classifying bacterial essential genes using transposon insertion density derived from transposon insertion sequencing data. We implement a Markov chain Monte Carlo sampling procedure to estimate the posterior probability that any given gene is essential. We implement a Bayesian decision theory approach to selecting essential genes. We assess the effectiveness of our approach via analysis of both simulated data and three previously published Escherichia coli, Salmonella Typhimurium and Staphylococcus aureus datasets. These three bacteria have relatively well characterized essential genes which allows us to test our classification procedure using receiver operating characteristic curves and area under the curves. We compare the classification performance with that of Bio-Tradis, a standard tool for bacterial gene classification. Results Our method is able to classify genes in the three datasets with areas under the curves between 0.967 and 0.983. Our simulated synthetic datasets show that both the number of insertions and the extent to which insertions are tolerated in the distal regions of essential genes are both important in determining classification accuracy. Importantly our method gives the user the option of classifying essential genes based on the user-supplied costs of false discovery and false non-discovery. Availability and implementation An R package that implements the method presented in this paper is available for download from https://github.com/Kevin-walters/insdens. Supplementary information Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Valentine U Nlebedim
- School of Mathematics and Statistics, University of Sheffield, Sheffield, S10 2TN, United Kingdom
| | - Roy R Chaudhuri
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, S10 2TN, United Kingdom
| | - Kevin Walters
- School of Mathematics and Statistics, University of Sheffield, Sheffield, S10 2TN, United Kingdom
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46
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Larivière D, Wickham L, Keiler K, Nekrutenko A. Reproducible and accessible analysis of transposon insertion sequencing in Galaxy for qualitative essentiality analyses. BMC Microbiol 2021; 21:168. [PMID: 34090324 PMCID: PMC8178898 DOI: 10.1186/s12866-021-02184-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Accepted: 04/08/2021] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Significant progress has been made in advancing and standardizing tools for human genomic and biomedical research. Yet, the field of next-generation sequencing (NGS) analysis for microorganisms (including multiple pathogens) remains fragmented, lacks accessible and reusable tools, is hindered by local computational resource limitations, and does not offer widely accepted standards. One such "problem areas" is the analysis of Transposon Insertion Sequencing (TIS) data. TIS allows probing of almost the entire genome of a microorganism by introducing random insertions of transposon-derived constructs. The impact of the insertions on the survival and growth under specific conditions provides precise information about genes affecting specific phenotypic characteristics. A wide array of tools has been developed to analyze TIS data. Among the variety of options available, it is often difficult to identify which one can provide a reliable and reproducible analysis. RESULTS Here we sought to understand the challenges and propose reliable practices for the analysis of TIS experiments. Using data from two recent TIS studies, we have developed a series of workflows that include multiple tools for data de-multiplexing, promoter sequence identification, transposon flank alignment, and read count repartition across the genome. Particular attention was paid to quality control procedures, such as determining the optimal tool parameters for the analysis and removal of contamination. CONCLUSIONS Our work provides an assessment of the currently available tools for TIS data analysis. It offers ready to use workflows that can be invoked by anyone in the world using our public Galaxy platform ( https://usegalaxy.org ). To lower the entry barriers, we have also developed interactive tutorials explaining details of TIS data analysis procedures at https://bit.ly/gxy-tis .
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Affiliation(s)
- Delphine Larivière
- Biochemistry and Molecular Biology Department, Eberly College of Science, The Pennsylvania State University, University Park, Pennsylvania, USA
- The Galaxy Project
| | - Laura Wickham
- Biochemistry and Molecular Biology Department, Eberly College of Science, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Kenneth Keiler
- Biochemistry and Molecular Biology Department, Eberly College of Science, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Anton Nekrutenko
- Biochemistry and Molecular Biology Department, Eberly College of Science, The Pennsylvania State University, University Park, Pennsylvania, USA.
- The Galaxy Project, .
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47
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Esener N, Maciel-Guerra A, Giebel K, Lea D, Green MJ, Bradley AJ, Dottorini T. Mass spectrometry and machine learning for the accurate diagnosis of benzylpenicillin and multidrug resistance of Staphylococcus aureus in bovine mastitis. PLoS Comput Biol 2021; 17:e1009108. [PMID: 34115749 PMCID: PMC8221797 DOI: 10.1371/journal.pcbi.1009108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 06/23/2021] [Accepted: 05/22/2021] [Indexed: 01/16/2023] Open
Abstract
Staphylococcus aureus is a serious human and animal pathogen threat exhibiting extraordinary capacity for acquiring new antibiotic resistance traits in the pathogen population worldwide. The development of fast, affordable and effective diagnostic solutions capable of discriminating between antibiotic-resistant and susceptible S. aureus strains would be of huge benefit for effective disease detection and treatment. Here we develop a diagnostics solution that uses Matrix-Assisted Laser Desorption/Ionisation-Time of Flight Mass Spectrometry (MALDI-TOF) and machine learning, to identify signature profiles of antibiotic resistance to either multidrug or benzylpenicillin in S. aureus isolates. Using ten different supervised learning techniques, we have analysed a set of 82 S. aureus isolates collected from 67 cows diagnosed with bovine mastitis across 24 farms. For the multidrug phenotyping analysis, LDA, linear SVM, RBF SVM, logistic regression, naïve Bayes, MLP neural network and QDA had Cohen's kappa values over 85.00%. For the benzylpenicillin phenotyping analysis, RBF SVM, MLP neural network, naïve Bayes, logistic regression, linear SVM, QDA, LDA, and random forests had Cohen's kappa values over 85.00%. For the benzylpenicillin the diagnostic systems achieved up to (mean result ± standard deviation over 30 runs on the test set): accuracy = 97.54% ± 1.91%, sensitivity = 99.93% ± 0.25%, specificity = 95.04% ± 3.83%, and Cohen's kappa = 95.04% ± 3.83%. Moreover, the diagnostic platform complemented by a protein-protein network and 3D structural protein information framework allowed the identification of five molecular determinants underlying the susceptible and resistant profiles. Four proteins were able to classify multidrug-resistant and susceptible strains with 96.81% ± 0.43% accuracy. Five proteins, including the previous four, were able to classify benzylpenicillin resistant and susceptible strains with 97.54% ± 1.91% accuracy. Our approach may open up new avenues for the development of a fast, affordable and effective day-to-day diagnostic solution, which would offer new opportunities for targeting resistant bacteria.
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MESH Headings
- Animals
- Bacterial Proteins/chemistry
- Cattle
- Computational Biology
- Diagnosis, Computer-Assisted/methods
- Diagnosis, Computer-Assisted/statistics & numerical data
- Diagnosis, Computer-Assisted/veterinary
- Drug Resistance, Multiple, Bacterial
- Female
- Humans
- Mastitis, Bovine/diagnosis
- Mastitis, Bovine/drug therapy
- Mastitis, Bovine/microbiology
- Methicillin-Resistant Staphylococcus aureus/chemistry
- Methicillin-Resistant Staphylococcus aureus/drug effects
- Methicillin-Resistant Staphylococcus aureus/isolation & purification
- Microbial Sensitivity Tests
- Models, Molecular
- Penicillin G/pharmacology
- Protein Interaction Maps
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
- Staphylococcal Infections/diagnosis
- Staphylococcal Infections/drug therapy
- Staphylococcal Infections/veterinary
- Staphylococcus aureus/chemistry
- Staphylococcus aureus/drug effects
- Staphylococcus aureus/isolation & purification
- Supervised Machine Learning
- United Kingdom
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Affiliation(s)
- Necati Esener
- University of Nottingham, School of Veterinary Medicine and Science, Sutton Bonington, United Kingdom
| | - Alexandre Maciel-Guerra
- University of Nottingham School of Computer Science, Jubilee Campus, Nottingham, United Kingdom
| | | | - Daniel Lea
- Digital Research Service, University of Nottingham, Sutton Bonington, United Kingdom
| | - Martin J. Green
- University of Nottingham, School of Veterinary Medicine and Science, Sutton Bonington, United Kingdom
| | - Andrew J. Bradley
- University of Nottingham, School of Veterinary Medicine and Science, Sutton Bonington, United Kingdom
- Quality Milk Management Services ltd, Easton, United Kingdom
| | - Tania Dottorini
- University of Nottingham, School of Veterinary Medicine and Science, Sutton Bonington, United Kingdom
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The Diadenylate Cyclase CdaA Is Critical for Borrelia turicatae Virulence and Physiology. Infect Immun 2021; 89:IAI.00787-20. [PMID: 33846120 PMCID: PMC8316131 DOI: 10.1128/iai.00787-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 03/22/2021] [Indexed: 12/16/2022] Open
Abstract
Relapsing fever (RF), caused by spirochetes of the genus Borrelia, is a globally distributed, vector-borne disease with high prevalence in developing countries. To date, signaling pathways required for infection and virulence of RF Borrelia spirochetes are unknown. Cyclic di-AMP (c-di-AMP), synthesized by diadenylate cyclases (DACs), is a second messenger predominantly found in Gram-positive organisms that is linked to virulence and essential physiological processes. Although Borrelia is Gram-negative, it encodes one DAC (CdaA), and its importance remains undefined. To investigate the contribution of c-di-AMP signaling in the RF bacterium Borrelia turicatae, a cdaA mutant was generated. The mutant was significantly attenuated during murine infection, and genetic complementation reversed this phenotype. Because c-di-AMP is essential for viability in many bacteria, whole-genome sequencing was performed on cdaA mutants, and single-nucleotide polymorphisms identified potential suppressor mutations. Additionally, conditional mutation of cdaA confirmed that CdaA is important for normal growth and physiology. Interestingly, mutation of cdaA did not affect expression of homologs of virulence regulators whose levels are impacted by c-di-AMP signaling in the Lyme disease bacterium Borrelia burgdorferi Finally, the cdaA mutant had a significant growth defect when grown with salts, at decreased osmolarity, and without pyruvate. While the salt treatment phenotype was not reversed by genetic complementation, possibly due to suppressor mutations, growth defects at decreased osmolarity and in media lacking pyruvate could be attributed directly to cdaA inactivation. Overall, these results indicate CdaA is critical for B. turicatae pathogenesis and link c-di-AMP to osmoregulation and central metabolism in RF spirochetes.
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Sargison FA, Fitzgerald JR. Advances in Transposon Mutagenesis of Staphylococcus aureus: Insights into Pathogenesis and Antimicrobial Resistance. Trends Microbiol 2021; 29:282-285. [PMID: 33279382 DOI: 10.1016/j.tim.2020.11.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 11/03/2020] [Accepted: 11/05/2020] [Indexed: 10/22/2022]
Abstract
Our capacity to investigate the biology of the major human and animal pathogen Staphylococcus aureus has been greatly enhanced by technological advances in transposon (Tn) mutagenesis. Here we provide a perspective on how these advances can further our understanding of pathogenesis and antibiotic resistance.
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Affiliation(s)
- Fiona A Sargison
- Roslin Institute, University of Edinburgh, Easter Bush Campus, Edinburgh EH25 9RG, UK
| | - J Ross Fitzgerald
- Roslin Institute, University of Edinburgh, Easter Bush Campus, Edinburgh EH25 9RG, UK.
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50
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Sachla AJ, Helmann JD. Resource sharing between central metabolism and cell envelope synthesis. Curr Opin Microbiol 2021; 60:34-43. [PMID: 33581378 DOI: 10.1016/j.mib.2021.01.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 01/18/2021] [Accepted: 01/27/2021] [Indexed: 12/14/2022]
Abstract
Synthesis of the bacterial cell envelope requires a regulated partitioning of resources from central metabolism. Here, we consider the key metabolic junctions that provide the precursors needed to assemble the cell envelope. Peptidoglycan synthesis requires redirection of a glycolytic intermediate, fructose-6-phosphate, into aminosugar biosynthesis by the highly regulated branchpoint enzyme GlmS. MurA directs the downstream product, UDP-GlcNAc, specifically into peptidoglycan synthesis. Other shared resources required for cell envelope synthesis include the isoprenoid carrier lipid undecaprenyl phosphate and amino acids required for peptidoglycan cross-bridges. Assembly of the envelope requires a sharing of limited resources between competing cellular pathways and may additionally benefit from scavenging of metabolites released from neighboring cells or the formation of symbiotic relationships with a host.
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Affiliation(s)
- Ankita J Sachla
- Department of Microbiology, Cornell University, 370 Wing Hall, Wing Drive, Ithaca, NY 14853-8101, USA
| | - John D Helmann
- Department of Microbiology, Cornell University, 370 Wing Hall, Wing Drive, Ithaca, NY 14853-8101, USA.
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