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Pugazhendhi AS, Neal CJ, Ta KM, Molinari M, Kumar U, Wei F, Kolanthai E, Ady A, Drake C, Hughes M, Yooseph S, Seal S, Coathup MJ. A neoteric antibacterial ceria-silver nanozyme for abiotic surfaces. Biomaterials 2024; 307:122527. [PMID: 38518591 DOI: 10.1016/j.biomaterials.2024.122527] [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: 01/16/2024] [Revised: 03/01/2024] [Accepted: 03/08/2024] [Indexed: 03/24/2024]
Abstract
Community-associated and hospital-acquired infections caused by bacteria continue to yield major global challenges to human health. Bacterial contamination on abiotic surfaces is largely spread via high-touch surfaces and contemporary standard disinfection practices show limited efficacy, resulting in unsatisfactory therapeutic outcomes. New strategies that offer non-specific and broad protection are urgently needed. Herein, we report our novel ceria-silver nanozyme engineered at a molar ratio of 5:1 and with a higher trivalent (Ce3+) surface fraction. Our results reveal potent levels of surface catalytic activity on both wet and dry surfaces, with rapid, and complete eradication of Pseudomonas aeruginosa, Staphylococcus aureus, and methicillin resistant S. aureus, in both planktonic and biofilm form. Preferential electrostatic adherence of anionic bacteria to the cationic nanozyme surface leads to a catastrophic loss in both aerobic and anaerobic respiration, DNA damage, osmodysregulation, and finally, programmed bacterial lysis. Our data reveal several unique mechanistic avenues of synergistic ceria-Ag efficacy. Ag potentially increases the presence of Ce3+ sites at the ceria-Ag interface, thereby facilitating the formation of harmful H2O2, followed by likely permeation across the cell wall. Further, a weakened Ag-induced Ce-O bond may drive electron transfer from the Ec band to O2, thereby further facilitating the selective reduction of O2 toward H2O2 formation. Ag destabilizes the surface adsorption of molecular H2O2, potentially leading to higher concentrations of free H2O2 adjacent to bacteria. To this end, our results show that H2O2 and/or NO/NO2-/NO3- are the key liberators of antibacterial activity, with a limited immediate role being offered by nanozyme-induced ROS including O2•- and OH•, and likely other light-activated radicals. A mini-pilot proof-of-concept study performed in a pediatric dental clinic setting confirms residual, and continual nanozyme antibacterial efficacy over a 28-day period. These findings open a new approach to alleviate infections caused by bacteria for use on high-touch hard surfaces.
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Affiliation(s)
- Abinaya Sindu Pugazhendhi
- Biionix Cluster, College of Medicine, University of Central Florida, Orlando, FL, 32827, United States
| | - Craig J Neal
- Advanced Materials Processing and Analysis Centre, Nanoscience Technology Center (NSTC), University of Central Florida, Orlando, FL, 32826, United States
| | - Khoa Minh Ta
- Department of Chemical Sciences, School of Applied Sciences, University of Huddersfield, Huddersfield, HD1 3DH, United Kingdom
| | - Marco Molinari
- Department of Chemical Sciences, School of Applied Sciences, University of Huddersfield, Huddersfield, HD1 3DH, United Kingdom.
| | - Udit Kumar
- Advanced Materials Processing and Analysis Centre, Nanoscience Technology Center (NSTC), University of Central Florida, Orlando, FL, 32826, United States
| | - Fei Wei
- Biionix Cluster, College of Medicine, University of Central Florida, Orlando, FL, 32827, United States
| | - Elayaraja Kolanthai
- Advanced Materials Processing and Analysis Centre, Nanoscience Technology Center (NSTC), University of Central Florida, Orlando, FL, 32826, United States
| | - Andrew Ady
- Biionix Cluster, College of Medicine, University of Central Florida, Orlando, FL, 32827, United States
| | - Christina Drake
- Kismet Technologies, 7101 TPC Drive, Suite 130, Orlando, FL, 32822, United States
| | - Megan Hughes
- University of Cardiff, Cardiff, CF10 3AT, Wales, United Kingdom
| | - Shibu Yooseph
- Kravis Department of Integrated Sciences, Claremont McKenna College, Claremont, CA 91711, United States
| | - Sudipta Seal
- Biionix Cluster, College of Medicine, University of Central Florida, Orlando, FL, 32827, United States; Advanced Materials Processing and Analysis Centre, Nanoscience Technology Center (NSTC), University of Central Florida, Orlando, FL, 32826, United States
| | - Melanie J Coathup
- Biionix Cluster, College of Medicine, University of Central Florida, Orlando, FL, 32827, United States.
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Hoffmann A, Steffens U, Maček B, Franz-Wachtel M, Nieselt K, Harbig TA, Scherlach K, Hertweck C, Sahl HG, Bierbaum G. The unusual mode of action of the polyketide glycoside antibiotic cervimycin C. mSphere 2024; 9:e0076423. [PMID: 38722162 DOI: 10.1128/msphere.00764-23] [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: 01/02/2024] [Accepted: 03/28/2024] [Indexed: 05/30/2024] Open
Abstract
Cervimycins A-D are bis-glycosylated polyketide antibiotics produced by Streptomyces tendae HKI 0179 with bactericidal activity against Gram-positive bacteria. In this study, cervimycin C (CmC) treatment caused a spaghetti-like phenotype in Bacillus subtilis 168, with elongated curved cells, which stayed joined after cell division, and exhibited a chromosome segregation defect, resulting in ghost cells without DNA. Electron microscopy of CmC-treated Staphylococcus aureus (3 × MIC) revealed swollen cells, misshapen septa, cell wall thickening, and a rough cell wall surface. Incorporation tests in B. subtilis indicated an effect on DNA biosynthesis at high cervimycin concentrations. Indeed, artificial downregulation of the DNA gyrase subunit B gene (gyrB) increased the activity of cervimycin in agar diffusion tests, and, in high concentrations (starting at 62.5 × MIC), the antibiotic inhibited S. aureus DNA gyrase supercoiling activity in vitro. To obtain a more global view on the mode of action of CmC, transcriptomics and proteomics of cervimycin treated versus untreated S. aureus cells were performed. Interestingly, 3 × MIC of cervimycin did not induce characteristic responses, which would indicate disturbance of the DNA gyrase activity in vivo. Instead, cervimycin induced the expression of the CtsR/HrcA heat shock operon and the expression of autolysins, exhibiting similarity to the ribosome-targeting antibiotic gentamicin. In summary, we identified the DNA gyrase as a target, but at low concentrations, electron microscopy and omics data revealed a more complex mode of action of cervimycin, which comprised induction of the heat shock response, indicating protein stress in the cell.IMPORTANCEAntibiotic resistance of Gram-positive bacteria is an emerging problem in modern medicine, and new antibiotics with novel modes of action are urgently needed. Secondary metabolites from Streptomyces species are an important source of antibiotics, like the cervimycin complex produced by Streptomyces tendae HKI 0179. The phenotypic response of Bacillus subtilis and Staphylococcus aureus toward cervimycin C indicated a chromosome segregation and septum formation defect. This effect was at first attributed to an interaction between cervimycin C and the DNA gyrase. However, omics data of cervimycin treated versus untreated S. aureus cells indicated a different mode of action, because the stress response did not include the SOS response but resembled the response toward antibiotics that induce mistranslation or premature chain termination and cause protein stress. In summary, these results point toward a possibly novel mechanism that generates protein stress in the cells and subsequently leads to defects in cell and chromosome segregation.
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Affiliation(s)
- Alina Hoffmann
- University Hospital Bonn, Institute of Medical Microbiology, Immunology and Parasitology, Bonn, Germany
| | - Ursula Steffens
- University Hospital Bonn, Institute of Medical Microbiology, Immunology and Parasitology, Bonn, Germany
| | - Boris Maček
- University of Tübingen, Proteome Center Tübingen, Tübingen, Germany
| | | | - Kay Nieselt
- University of Tübingen, Interfaculty Institute for Bioinformatics and Medical Informatics, Tübingen, Germany
| | - Theresa Anisja Harbig
- University of Tübingen, Interfaculty Institute for Bioinformatics and Medical Informatics, Tübingen, Germany
| | - Kirstin Scherlach
- Leibniz Institute for Natural Product Research and Infection Biology-Hans Knöll Institute (HKI), Jena, Germany
| | - Christian Hertweck
- Leibniz Institute for Natural Product Research and Infection Biology-Hans Knöll Institute (HKI), Jena, Germany
- Friedrich Schiller University Jena, Institute of Microbiology, Faculty of Biological Sciences, Jena, Germany
| | - Hans-Georg Sahl
- University of Bonn, Institute for Pharmaceutical Microbiology, Bonn, Germany
| | - Gabriele Bierbaum
- University Hospital Bonn, Institute of Medical Microbiology, Immunology and Parasitology, Bonn, Germany
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Zhou C, Pawline MB, Pironti A, Morales SM, Perault AI, Ulrich RJ, Podkowik M, Lejeune A, DuMont A, Stubbe FX, Korman A, Jones DR, Schluter J, Richardson AR, Fey PD, Drlica K, Cadwell K, Torres VJ, Shopsin B. Microbiota and metabolic adaptation shape Staphylococcus aureus virulence and antimicrobial resistance during intestinal colonization. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.11.593044. [PMID: 38766195 PMCID: PMC11100824 DOI: 10.1101/2024.05.11.593044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Depletion of microbiota increases susceptibility to gastrointestinal colonization and subsequent infection by opportunistic pathogens such as methicillin-resistant Staphylococcus aureus (MRSA). How the absence of gut microbiota impacts the evolution of MRSA is unknown. The present report used germ-free mice to investigate the evolutionary dynamics of MRSA in the absence of gut microbiota. Through genomic analyses and competition assays, we found that MRSA adapts to the microbiota-free gut through sequential genetic mutations and structural changes that enhance fitness. Initially, these adaptations increase carbohydrate transport; subsequently, evolutionary pathways largely diverge to enhance either arginine metabolism or cell wall biosynthesis. Increased fitness in arginine pathway mutants depended on arginine catabolic genes, especially nos and arcC, which promote microaerobic respiration and ATP generation, respectively. Thus, arginine adaptation likely improves redox balance and energy production in the oxygen-limited gut environment. Findings were supported by human gut metagenomic analyses, which suggest the influence of arginine metabolism on colonization. Surprisingly, these adaptive genetic changes often reduced MRSA's antimicrobial resistance and virulence. Furthermore, resistance mutation, typically associated with decreased virulence, also reduced colonization fitness, indicating evolutionary trade-offs among these traits. The presence of normal microbiota inhibited these adaptations, preserving MRSA's wild-type characteristics that effectively balance virulence, resistance, and colonization fitness. The results highlight the protective role of gut microbiota in preserving a balance of key MRSA traits for long-term ecological success in commensal populations, underscoring the potential consequences on MRSA's survival and fitness during and after host hospitalization and antimicrobial treatment.
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Affiliation(s)
- Chunyi Zhou
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Miranda B. Pawline
- Department of Medicine, Division of Infectious Diseases, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Alejandro Pironti
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY 10016, USA
- Antimicrobial-Resistant Pathogens Program, New York University Grossman School of Medicine, New York, NY 10016, USA
- Microbial Computational Genomic Core Lab, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Sabrina M. Morales
- Department of Medicine, Division of Infectious Diseases, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Andrew I. Perault
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Robert J. Ulrich
- Department of Medicine, Division of Infectious Diseases, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Magdalena Podkowik
- Department of Medicine, Division of Infectious Diseases, New York University Grossman School of Medicine, New York, NY 10016, USA
- Antimicrobial-Resistant Pathogens Program, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Alannah Lejeune
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Ashley DuMont
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | | | - Aryeh Korman
- Metabolomics Core Resource Laboratory, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Drew R. Jones
- Metabolomics Core Resource Laboratory, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Jonas Schluter
- Institute for Systems Genetics, Department of Microbiology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Anthony R. Richardson
- Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, PA 15219, USA
| | - Paul D. Fey
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Karl Drlica
- Public Health Research Institute, New Jersey Medical School, Rutgers University, Newark, NJ 07102, USA
- Department of Microbiology, Biochemistry & Molecular Genetics, New Jersey Medical School, Rutgers University, Newark, NJ 07102, USA
| | - Ken Cadwell
- Division of Gastroenterology and Hepatology, Department of Medicine, New York University Grossman School of Medicine, New York, NY 10016, USA
- Kimmel Center for Biology and Medicine at the Skirball Institute, New York University, Grossman School of Medicine, New York, NY 10016, USA
| | - Victor J. Torres
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY 10016, USA
- Antimicrobial-Resistant Pathogens Program, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Bo Shopsin
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY 10016, USA
- Department of Medicine, Division of Infectious Diseases, New York University Grossman School of Medicine, New York, NY 10016, USA
- Antimicrobial-Resistant Pathogens Program, New York University Grossman School of Medicine, New York, NY 10016, USA
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Liu Y, Cheng YY, Thompson J, Zhou Z, Vivas EI, Warren MF, Rey FE, Anantharaman K, Venturelli OS. Shaping human gut community assembly and butyrate production by controlling the arginine dihydrolase pathway. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.01.10.523442. [PMID: 37986770 PMCID: PMC10659395 DOI: 10.1101/2023.01.10.523442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
The arginine dihydrolase pathway (arc operon) present in a subset of diverse human gut species enables arginine catabolism. This specialized metabolic pathway can alter environmental pH and nitrogen availability, which in turn could shape gut microbiota inter-species interactions. By exploiting synthetic control of gene expression, we investigated the role of the arc operon in probiotic Escherichia coli Nissle 1917 on human gut community assembly and health-relevant metabolite profiles in vitro and in the murine gut. By stabilizing environmental pH, the arc operon reduced variability in community composition across different initial pH perturbations. The abundance of butyrate producing bacteria were altered in response to arc operon activity and butyrate production was enhanced in a physiologically relevant pH range. While the presence of the arc operon altered community dynamics, it did not impact production of short chain fatty acids. Dynamic computational modeling of pH-mediated interactions reveals the quantitative contribution of this mechanism to community assembly. In sum, our framework to quantify the contribution of molecular pathways and mechanism modalities on microbial community dynamics and functions could be applied more broadly.
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Affiliation(s)
- Yiyi Liu
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison WI 53706
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706
| | - Yu-Yu Cheng
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706
| | - Jaron Thompson
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison WI 53706
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706
| | - Zhichao Zhou
- Department of Bacteriology, University of Wisconsin-Madison, WI 53706
| | - Eugenio I. Vivas
- Department of Bacteriology, University of Wisconsin-Madison, WI 53706
- Gnotobiotic Animal Core Facility, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Matthew F. Warren
- Department of Bacteriology, University of Wisconsin-Madison, WI 53706
| | - Federico E. Rey
- Department of Bacteriology, University of Wisconsin-Madison, WI 53706
| | | | - Ophelia S. Venturelli
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison WI 53706
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706
- Department of Bacteriology, University of Wisconsin-Madison, WI 53706
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5
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Hauserman MR, Ferraro MJ, Carroll RK, Rice KC. Altered quorum sensing and physiology of Staphylococcus aureus during spaceflight detected by multi-omics data analysis. NPJ Microgravity 2024; 10:2. [PMID: 38191486 PMCID: PMC10774393 DOI: 10.1038/s41526-023-00343-7] [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: 07/10/2023] [Accepted: 12/15/2023] [Indexed: 01/10/2024] Open
Abstract
Staphylococcus aureus colonizes the nares of approximately 30% of humans, a risk factor for opportunistic infections. To gain insight into S. aureus virulence potential in the spaceflight environment, we analyzed RNA-Seq, cellular proteomics, and metabolomics data from the "Biological Research in Canisters-23" (BRIC-23) GeneLab spaceflight experiment, a mission designed to measure the response of S. aureus to growth in low earth orbit on the international space station. This experiment used Biological Research in Canisters-Petri Dish Fixation Units (BRIC-PDFUs) to grow asynchronous ground control and spaceflight cultures of S. aureus for 48 h. RNAIII, the effector of the Accessory Gene Regulator (Agr) quorum sensing system, was the most highly upregulated gene transcript in spaceflight relative to ground controls. The agr operon gene transcripts were also highly upregulated during spaceflight, followed by genes encoding phenol-soluble modulins and secreted proteases, which are positively regulated by Agr. Upregulated spaceflight genes/proteins also had functions related to urease activity, type VII-like Ess secretion, and copper transport. We also performed secretome analysis of BRIC-23 culture supernatants, which revealed that spaceflight samples had increased abundance of secreted virulence factors, including Agr-regulated proteases (SspA, SspB), staphylococcal nuclease (Nuc), and EsxA (secreted by the Ess system). These data also indicated that S. aureus metabolism is altered in spaceflight conditions relative to the ground controls. Collectively, these data suggest that S. aureus experiences increased quorum sensing and altered expression of virulence factors in response to the spaceflight environment that may impact its pathogenic potential.
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Affiliation(s)
- Matthew R Hauserman
- Department of Microbiology and Cell Science, IFAS, University of Florida, Gainesville, FL, USA
| | - Mariola J Ferraro
- Department of Microbiology and Cell Science, IFAS, University of Florida, Gainesville, FL, USA
| | - Ronan K Carroll
- Department of Biological Sciences, Ohio University, Athens, OH, USA
| | - Kelly C Rice
- Department of Microbiology and Cell Science, IFAS, University of Florida, Gainesville, FL, USA.
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Jiang JH, Cameron DR, Nethercott C, Aires-de-Sousa M, Peleg AY. Virulence attributes of successful methicillin-resistant Staphylococcus aureus lineages. Clin Microbiol Rev 2023; 36:e0014822. [PMID: 37982596 PMCID: PMC10732075 DOI: 10.1128/cmr.00148-22] [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] [Indexed: 11/21/2023] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of severe and often fatal infections. MRSA epidemics have occurred in waves, whereby a previously successful lineage has been replaced by a more fit and better adapted lineage. Selection pressures in both hospital and community settings are not uniform across the globe, which has resulted in geographically distinct epidemiology. This review focuses on the mechanisms that trigger the establishment and maintenance of current, dominant MRSA lineages across the globe. While the important role of antibiotic resistance will be mentioned throughout, factors which influence the capacity of S. aureus to colonize and cause disease within a host will be the primary focus of this review. We show that while MRSA possesses a diverse arsenal of toxins including alpha-toxin, the success of a lineage involves more than just producing toxins that damage the host. Success is often attributed to the acquisition or loss of genetic elements involved in colonization and niche adaptation such as the arginine catabolic mobile element, as well as the activity of regulatory systems, and shift metabolism accordingly (e.g., the accessory genome regulator, agr). Understanding exactly how specific MRSA clones cause prolonged epidemics may reveal targets for therapies, whereby both core (e.g., the alpha toxin) and acquired virulence factors (e.g., the Panton-Valentine leukocidin) may be nullified using anti-virulence strategies.
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Affiliation(s)
- Jhih-Hang Jiang
- Department of Microbiology, Infection Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
- Department of Infectious Diseases, The Alfred Hospital and Central Clinical School, Monash University, Melbourne, Victoria, Australia
| | - David R. Cameron
- Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Cara Nethercott
- Department of Microbiology, Infection Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Marta Aires-de-Sousa
- Laboratory of Molecular Genetics, Institutode Tecnologia Químicae Biológica António Xavier (ITQB-NOVA), Universidade Nova de Lisboa, Oeiras, Portugal
- Escola Superior de Saúde da Cruz Vermelha Portuguesa-Lisboa (ESSCVP-Lisboa), Lisbon, Portugal
| | - Anton Y. Peleg
- Department of Microbiology, Infection Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
- Department of Infectious Diseases, The Alfred Hospital and Central Clinical School, Monash University, Melbourne, Victoria, Australia
- Centre to Impact Antimicrobial Resistance, Monash University, Clayton, Melbourne, Victoria, Australia
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Stephens AC, Banerjee SK, Richardson AR. Specialized phosphate transport is essential for Staphylococcus aureus nitric oxide resistance. mBio 2023; 14:e0245123. [PMID: 37937971 PMCID: PMC10746193 DOI: 10.1128/mbio.02451-23] [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: 09/13/2023] [Accepted: 10/03/2023] [Indexed: 11/09/2023] Open
Abstract
Staphylococcus aureus is a major human pathogen capable of causing a variety of diseases ranging from skin and soft tissue infections to systemic presentations such as sepsis, endocarditis, and osteomyelitis. For S. aureus to persist as a pathogen in these environments, it must be able to resist the host immune response, including the production of reactive oxygen and nitrogen species (e.g., nitric oxide, NO·). Extensive work from our lab has shown that S. aureus is highly resistant to NO·, especially in the presence of glucose. RNA-seq performed on S. aureus exposed to NO· in the presence and absence of glucose showed a new system important for NO· resistance-phosphate transport. The phosphate transport systems pstSCAB and nptA are both upregulated upon NO·-exposure, particularly in the presence of glucose. Both are key for phosphate transport at an alkaline pH, which the cytosol of S. aureus becomes under NO· stress. Accordingly, the ΔpstSΔnptA mutant is attenuated under NO stress in vitro as well as in macrophage and murine infection models. This work defines a new role in infection for two phosphate transporters in S. aureus and provides insight into the complex system that is NO· resistance in S. aureus.IMPORTANCEStaphylococcus aureus is a bacterial pathogen capable of causing a wide variety of disease in humans. S. aureus is unique in its ability to resist the host immune response, including the antibacterial compound known as nitric oxide (NO·). We used an RNA-sequencing approach to better understand the impact of NO· on S. aureus in different environments. We discovered that inorganic phosphate transport is induced by the presence of NO·. Phosphate is important for the generation of energy from glucose, a carbon source favored by S. aureus. We show that the absence of these phosphate transporters causes lowered energy levels in S. aureus. We find that these phosphate transporters are essential for S. aureus to grow in the presence of NO· and to cause infection. Our work here contributes significantly to our understanding of S. aureus NO· resistance and provides a new context in which S. aureus phosphate transporters are essential.
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Affiliation(s)
- Amelia C. Stephens
- Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Srijon K. Banerjee
- Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Anthony R. Richardson
- Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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8
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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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9
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Fu T, Fan Z, Li Y, Li Z, Zhao H, Feng Y, Xue G, Cui J, Yan C, Gan L, Feng J, Yuan J, You F. Roles of the Crp/Fnr Family Regulator ArcR in the Hemolysis and Biofilm of Staphylococcus aureus. Microorganisms 2023; 11:1656. [PMID: 37512829 PMCID: PMC10384999 DOI: 10.3390/microorganisms11071656] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 06/20/2023] [Accepted: 06/22/2023] [Indexed: 07/30/2023] Open
Abstract
Staphylococcus aureus is an opportunistic human pathogen that is often involved in severe infections such as pneumonia and sepsis in which bacterial virulence factors play a key role. Infections caused by S. aureus are often difficult to eradicate, particularly when they are associated with biofilm. The physiological roles of the Crp/Fnr family regulator ArcR are elusive in S. aureus. In this study, it was found that the deletion of arcR increased the hemolytic ability and biofilm formation in S. aureus. Differential gene expression analysis by RNA-seq and real-time quantitative reverse transcription PCR showed that genes associated with hemolytic ability (hla and hlb) and biofilm formation (icaA, icaB, icaC and icaD) were significantly upregulated compared with those in the wild-type strain. The results revealed that ArcR regulated the expression of the hla and ica operon by binding to their promoter regions, respectively. This study provided new insights into the functional importance of ArcR in regulating the virulence and biofilm of S. aureus.
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Affiliation(s)
- Tongtong Fu
- School of Basic Medical Sciences, Peking University, Beijing 100020, China
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Zheng Fan
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Yujie Li
- Department of Life Science and Medicine, University of Science and Technology of China, Hefei 230026, China
| | - Zhoufei Li
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Hanqing Zhao
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Yanling Feng
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Guanhua Xue
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Jinghua Cui
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Chao Yan
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Lin Gan
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Junxia Feng
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Jing Yuan
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Fuping You
- School of Basic Medical Sciences, Peking University, Beijing 100020, China
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10
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Wang Z, Lu J, Yuan Z, Pi W, Huang X, Lin X, Zhang Y, Lei H, Wang P. Natural Carrier-Free Binary Small Molecule Self-Assembled Hydrogel Synergize Antibacterial Effects and Promote Wound Healing by Inhibiting Virulence Factors and Alleviating the Inflammatory Response. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2205528. [PMID: 36446719 DOI: 10.1002/smll.202205528] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 11/16/2022] [Indexed: 06/16/2023]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA)-infected skin wounds have caused a variety of diseases and seriously endanger global public health. Therefore, multidimensional strategies are urgently to find antibacterial dressings to combat bacterial infections. Antibacterial hydrogels are considered potential wound dressing, while their clinical translation is limited due to the unpredictable risks and high costs of carrier excipients. it is found that the natural star antibacterial and anti-inflammatory phytochemicals baicalin (BA) and sanguinarine (SAN) can directly self-assemble through non-covalent bonds such as electrostatic attraction, π-π stacking, and hydrogen bonding to form carrier-free binary small molecule hydrogel. In addition, BA-SAN gel exhibited a synergistic inhibitory effect on MRSA. And its plasticity and injectability allowed it to be applied as a wound dressing. Due to the matched physicochemical properties and synergistic therapeutic effects, BA-SAN gel can inhibit bacterial virulence factors, alleviate wound inflammation, promote wound healing, and has good biocompatibility. The current study not only provided an antibacterial hydrogel with clinical value but also opened up new prospects that carrier-free hydrogels can be designed and originated from clinically used small-molecule phytochemicals.
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Affiliation(s)
- Zhijia Wang
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing, 102488, P. R. China
| | - Jihui Lu
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing, 102488, P. R. China
| | - Zhihua Yuan
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing, 102488, P. R. China
| | - Wenmin Pi
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing, 102488, P. R. China
| | - Xuemei Huang
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing, 102488, P. R. China
| | - Xiaoyu Lin
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing, 102488, P. R. China
| | - Yaozhi Zhang
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing, 102488, P. R. China
| | - Haimin Lei
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing, 102488, P. R. China
| | - Penglong Wang
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing, 102488, P. R. China
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11
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Fu T, Fan Z, Li Y, Li Z, Du B, Liu S, Cui X, Zhang R, Zhao H, Feng Y, Xue G, Cui J, Yan C, Gan L, Feng J, Xu Z, Yu Z, Tian Z, Ding Z, Chen J, Chen Y, Yuan J. ArcR contributes to tolerance to fluoroquinolone antibiotics by regulating katA in Staphylococcus aureus. Front Microbiol 2023; 14:1106340. [PMID: 36910210 PMCID: PMC9998937 DOI: 10.3389/fmicb.2023.1106340] [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: 11/23/2022] [Accepted: 01/04/2023] [Indexed: 02/26/2023] Open
Abstract
Staphylococcus aureus is an opportunistic pathogen that shows a unique ability to quickly respond to a variety of antibiotics. The Crp/Fnr family transcriptional regulator ArcR controls expression of arginine deiminase pathway genes arcABDC, which enable the utilization of arginine as an energy source for cell growth under anaerobic conditions. However, ArcR shares low overall similarity with other Crp/Fnr family proteins, suggesting that they differ in the response to environmental stress. In this study, MIC and survival assays were performed to determine the role of ArcR in antibiotic resistance and tolerance. The results showed that deletion of arcR reduced tolerance of S.aureus to fluoroquinolone antibiotics, mainly through a defect in the response to oxidative stress. In ΔarcR mutant, the expression of the major catalase gene katA was downregulated, and katA overexpression restored bacterial resistance to oxidative stress and antibiotics. We showed that ArcR directly regulated katA transcription by binding to the promoter region of katA. Therefore, our results revealed the contribution of ArcR in bacterial tolerance to oxidative stress and subsequently to fluoroquinolones antibiotics. This study added our understanding on the role of Crp/Fnr family in bacterial susceptibility to antibiotics.
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Affiliation(s)
- Tongtong Fu
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Zheng Fan
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Yujie Li
- Department of Life Science and Medicine, University of Science and Technology of China, Hefei, China
| | - Zhoufei Li
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Bing Du
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Shiyu Liu
- Military Supplies and Energy Quality Supervision Station of NV, PLA, Beijing, China
| | - Xiaohu Cui
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Rui Zhang
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Hanqing Zhao
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Yanling Feng
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Guanhua Xue
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Jinghua Cui
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Chao Yan
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Lin Gan
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Junxia Feng
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Ziying Xu
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Zihui Yu
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Ziyan Tian
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Zanbo Ding
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Jinfeng Chen
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Yujie Chen
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
| | - Jing Yuan
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing, China
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12
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Shibamura-Fujiogi M, Wang X, Maisat W, Koutsogiannaki S, Li Y, Chen Y, Lee JC, Yuki K. GltS regulates biofilm formation in methicillin-resistant Staphylococcus aureus. Commun Biol 2022; 5:1284. [PMID: 36418899 PMCID: PMC9684512 DOI: 10.1038/s42003-022-04239-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 11/08/2022] [Indexed: 11/25/2022] Open
Abstract
Biofilm-based infection is a major healthcare burden. Methicillin-resistant Staphylococcus aureus (MRSA) is one of major organisms responsible for biofilm infection. Although biofilm is induced by a number of environmental signals, the molecule responsible for environmental sensing is not well delineated. Here we examined the role of ion transporters in biofilm formation and found that the sodium-glutamate transporter gltS played an important role in biofilm formation in MRSA. This was shown by gltS transposon mutant as well as its complementation. The lack of exogenous glutamate also enhanced biofilm formation in JE2 strain. The deficiency of exogenous glutamate intake accelerated endogenous glutamate/glutamine production, which led to the activation of the urea cycle. We also showed that urea cycle activation was critical for biofilm formation. In conclusion, we showed that gltS was a critical regulator of biofilm formation by controlling the intake of exogenous glutamate. An intervention to target glutamate intake may be a potential useful approach against biofilm.
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Affiliation(s)
- Miho Shibamura-Fujiogi
- Department of Anesthesiology, Critical Care and Pain Medicine, Cardiac Anesthesia Division, Boston Children's Hospital, Boston, MA, USA
- Department of Anaesthesia and Immunology, Harvard Medical School, Boston, MA, USA
| | - Xiaogang Wang
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Wiriya Maisat
- Department of Anesthesiology, Critical Care and Pain Medicine, Cardiac Anesthesia Division, Boston Children's Hospital, Boston, MA, USA
- Department of Anaesthesia and Immunology, Harvard Medical School, Boston, MA, USA
| | - Sophia Koutsogiannaki
- Department of Anesthesiology, Critical Care and Pain Medicine, Cardiac Anesthesia Division, Boston Children's Hospital, Boston, MA, USA
- Department of Anaesthesia and Immunology, Harvard Medical School, Boston, MA, USA
| | - Yunan Li
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Yue Chen
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Jean C Lee
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Koichi Yuki
- Department of Anesthesiology, Critical Care and Pain Medicine, Cardiac Anesthesia Division, Boston Children's Hospital, Boston, MA, USA.
- Department of Anaesthesia and Immunology, Harvard Medical School, Boston, MA, USA.
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13
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Catabolic Ornithine Carbamoyltransferase Activity Facilitates Growth of Staphylococcus aureus in Defined Medium Lacking Glucose and Arginine. mBio 2022; 13:e0039522. [PMID: 35475645 PMCID: PMC9239276 DOI: 10.1128/mbio.00395-22] [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: 11/29/2022] Open
Abstract
Previous studies have found that arginine biosynthesis in Staphylococcus aureus is repressed via carbon catabolite repression (CcpA), and proline is used as a precursor. Unexpectedly, however, robust growth of S. aureus is not observed in complete defined medium lacking both glucose and arginine (CDM-R). Mutants able to grow on agar-containing defined medium lacking arginine (CDM-R) were selected and found to contain mutations within ahrC, encoding the canonical arginine biosynthesis pathway repressor (AhrC), or single nucleotide polymorphisms (SNPs) upstream of the native arginine deiminase (ADI) operon arcA1B1D1C1. Reverse transcription-PCR (RT-PCR) studies found that mutations within ccpA or ahrC or SNPs identified upstream of arcA1B1D1C1 increased the transcription of both arcB1 and argGH, encoding ornithine carbamoyltransferase and argininosuccinate synthase/lyase, respectively, facilitating arginine biosynthesis. Furthermore, mutations within the AhrC homologue argR2 facilitated robust growth within CDM-R. Complementation with arcB1 or arcA1B1D1C1, but not argGH, rescued growth in CDM-R. Finally, supplementation of CDM-R with ornithine stimulated growth, as did mutations in genes (proC and rocA) that presumably increased the pyrroline-5-carboxylate and ornithine pools. Collectively, these data suggest that the transcriptional regulation of ornithine carbamoyltransferase and, in addition, the availability of intracellular ornithine pools regulate arginine biosynthesis in S. aureus in the absence of glucose. Surprisingly, ~50% of clinical S. aureus isolates were able to grow in CDM-R. These data suggest that S. aureus is selected to repress arginine biosynthesis in environments with or without glucose; however, mutants may be readily selected that facilitate arginine biosynthesis and growth in specific environments lacking arginine.
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14
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Microbial arginine deiminase: A multifaceted green catalyst in biomedical sciences. Int J Biol Macromol 2022; 196:151-162. [PMID: 34920062 DOI: 10.1016/j.ijbiomac.2021.12.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 11/03/2021] [Accepted: 12/04/2021] [Indexed: 12/18/2022]
Abstract
Arginine deiminase is a well-recognized guanidino-modifying hydrolase that catalyzes the conversion of L-arginine to citrulline and ammonia. Their biopotential to regress tumors via amino acid deprivation therapy (AADT) has been well established. PEGylated formulation of recombinant Mycoplasma ADI is in the last-phase clinical trials against various arginine-auxotrophic cancers like hepatocellular carcinoma, melanoma, and mesothelioma. Recently, ADIs have attained immense importance in several other biomedical applications, namely treatment of Alzheimer's, as an antiviral drug, bioproduction of nutraceutical L-citrulline and bio-analytics involving L-arginine detection. Considering the wide applications of this biodrug, the demand for ADI is expected to escalate several-fold in the coming years. However, the sustainable production aspects of the enzyme with improved pharmacokinetics is still limited, creating bottlenecks for effective biopharmaceutical development. To circumvent the lacunae in enzyme production with appropriate paradigms of 'quality-by-design' an explicit overview of its properties with 'biobetter' formulations strategies are required. Present review provides an insight into all the potential biomedical applications of ADI along with the improvements required for its reach to clinics. Recent research advances with special emphasis on the development of ADI as a 'biobetter' enzyme have also been comprehensively elaborated.
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15
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Desgranges E, Barrientos L, Herrgott L, Marzi S, Toledo-Arana A, Moreau K, Vandenesch F, Romby P, Caldelari I. The 3'UTR-derived sRNA RsaG coordinates redox homeostasis and metabolism adaptation in response to glucose-6-phosphate uptake in Staphylococcus aureus. Mol Microbiol 2021; 117:193-214. [PMID: 34783400 DOI: 10.1111/mmi.14845] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 11/08/2021] [Accepted: 11/11/2021] [Indexed: 01/28/2023]
Abstract
Staphylococcus aureus RsaG is a 3'-untranslated region (3'UTR) derived sRNA from the conserved uhpT gene encoding a glucose-6-phosphate (G6P) transporter expressed in response to extracellular G6P. The transcript uhpT-RsaG undergoes degradation from 5'- to 3'-end by the action of the exoribonucleases J1/J2, which are blocked by a stable hairpin structure at the 5'-end of RsaG, leading to its accumulation. RsaG together with uhpT is induced when bacteria are internalized into host cells or in the presence of mucus-secreting cells. Using MS2-affinity purification coupled with RNA sequencing, several RNAs were identified as targets including mRNAs encoding the transcriptional factors Rex, CcpA, SarA, and the sRNA RsaI. Our data suggested that RsaG contributes to the control of redox homeostasis and adjusts metabolism to changing environmental conditions. RsaG uses different molecular mechanisms to stabilize, degrade, or repress the translation of its mRNA targets. Although RsaG is conserved only in closely related species, the uhpT 3'UTR of the ape pathogen S. simiae harbors an sRNA, whose sequence is highly different, and which does not respond to G6P levels. Our results hypothesized that the 3'UTRs from UhpT transporter encoding mRNAs could have rapidly evolved to enable adaptation to host niches.
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Affiliation(s)
- Emma Desgranges
- Architecture et Réactivité de l'ARN, UPR9002, CNRS, Université de Strasbourg, Strasbourg, France
| | - Laura Barrientos
- Architecture et Réactivité de l'ARN, UPR9002, CNRS, Université de Strasbourg, Strasbourg, France
| | - Lucas Herrgott
- Architecture et Réactivité de l'ARN, UPR9002, CNRS, Université de Strasbourg, Strasbourg, France
| | - Stefano Marzi
- Architecture et Réactivité de l'ARN, UPR9002, CNRS, Université de Strasbourg, Strasbourg, France
| | | | - Karen Moreau
- CIRI, Centre International de Recherche en Infectiologie, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, École Normale Supérieure de Lyon, Hospices Civils de Lyon, Université de Lyon, Lyon, France
| | - François Vandenesch
- CIRI, Centre International de Recherche en Infectiologie, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, École Normale Supérieure de Lyon, Hospices Civils de Lyon, Université de Lyon, Lyon, France
| | - Pascale Romby
- Architecture et Réactivité de l'ARN, UPR9002, CNRS, Université de Strasbourg, Strasbourg, France
| | - Isabelle Caldelari
- Architecture et Réactivité de l'ARN, UPR9002, CNRS, Université de Strasbourg, Strasbourg, France
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16
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Lin J, Luo X, Gänzle MG, Luo L. Characterization of the two nonidentical ArgR regulators of Tetragenococcus halophilus and their regulatory effects on arginine metabolism. Appl Microbiol Biotechnol 2020; 104:8775-8787. [PMID: 32880693 DOI: 10.1007/s00253-020-10868-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 08/06/2020] [Accepted: 08/26/2020] [Indexed: 11/25/2022]
Abstract
The halophilic lactic acid bacterium Tetragenococcus halophilus has been widely used in high-salinity fermentation processes of food. Previous studies have indicated that the catabolism of arginine may contribute to the osmotic stress adaptation of T. halophilus. Unusually, in the chromosome of T. halophilus, preceding the arginine deiminase (ADI) operon, locate two co-transcribed genes, both encoding an ArgR regulator; similar structure was rarely found and the roles of the regulators have not been demonstrated. In the current study, regulatory roles of these two nonidentical ArgR regulators on the arginine metabolism of T. halophilus were investigated. The results show that these two regulators play different roles in arginine metabolism, ArgR1 acts as a negative regulator of the ADI pathway by binding to the promoter sequences and repressing the transcription of genes, and the addition of arginine or hyper-osmotic stress conditions can abolish the ArgR1 repression, whereas ArgR2 negatively regulates the genes involved in arginine biosynthesis. Our study found that despite the commonly known roles of the ArgR regulators as the activator of arginine catabolism and the repressor of arginine biosynthesis, which are found in most studied bacteria possessed one ArgR regulator, the two nonidentical ArgR regulators of T. halophilus both act as repressors, and the repression by which is regulated when sensing changes of environments. By revealing the regulation of arginine metabolism, the current study provides molecular insights and potential tools for future applications of halophiles in biotechnology. KEY POINTS: • The expression of the ADI pathway of T. halophilus is regulated by carbon sources and osmotic stress. • The arginine metabolism process of T. halophilus is fine-tuned by the two ArgR regulators. • The ADI pathway may contribute to the osmotic stress adaptation by generating more energy and accumulating citrulline which acts as compatible solute.
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Affiliation(s)
- Jieting Lin
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, People's Republic of China
- Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou, 510006, People's Republic of China
- Department of Agricultural, Food and Nutritional Science, University of Alberta, 4-10 Agriculture/Forestry Centre, Edmonton, Alberta, T6G 2P5, Canada
| | - Xiaotong Luo
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, People's Republic of China
- Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou, 510006, People's Republic of China
| | - Michael G Gänzle
- Department of Agricultural, Food and Nutritional Science, University of Alberta, 4-10 Agriculture/Forestry Centre, Edmonton, Alberta, T6G 2P5, Canada
| | - Lixin Luo
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, People's Republic of China.
- Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou, 510006, People's Republic of China.
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17
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Comparative Target Analysis of Chlorinated Biphenyl Antimicrobials Highlights MenG as a Molecular Target of Triclocarban. Appl Environ Microbiol 2020; 86:AEM.00933-20. [PMID: 32503913 DOI: 10.1128/aem.00933-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 06/03/2020] [Indexed: 12/18/2022] Open
Abstract
Triclocarban (TCC), a formerly used disinfectant, kills bacteria via an unknown mechanism of action. A structural hallmark is its N,N'-diaryl urea motif, which is also present in other antibiotics, including the recently reported small molecule PK150. We show here that, like PK150, TCC exhibits an inhibitory effect on Staphylococcus aureus menaquinone metabolism via inhibition of the biosynthesis protein demethylmenaquinone methyltransferase (MenG). However, the activity spectrum (MIC90) of TCC across a broad range of multidrug-resistant staphylococcus and enterococcus strains was much narrower than that of PK150. Accordingly, TCC did not cause an overactivation of signal peptidase SpsB, a hallmark of the PK150 mode of action. Furthermore, we were able to rule out inhibition of FabI, a confirmed target of the diaryl ether antibiotic triclosan (TCS). Differences in the target profiles of TCC and TCS were further investigated by proteomic analysis, showing complex but rather distinct changes in the protein expression profile of S. aureus Downregulation of the arginine deiminase pathway provided additional evidence for an effect on bacterial energy metabolism by TCC.IMPORTANCE TCC's widespread use as an antimicrobial agent has made it a ubiquitous environmental pollutant despite its withdrawal due to ecological and toxicological concerns. With its antibacterial mechanism of action still being unknown, we undertook a comparative target analysis between TCC, PK150 (a recently discovered antibacterial compound with structural resemblance to TCC), and TCS (another widely employed chlorinated biphenyl antimicrobial) in the bacterium Staphylococcus aureus We show that there are distinct differences in each compound's mode of action, but also identify a shared target between TCC and PK150, the interference with menaquinone metabolism by inhibition of MenG. The prevailing differences, however, which also manifest in a remarkably better broad-spectrum activity of PK150, suggest that even high levels of TCC or TCS resistance observed by continuous environmental exposure may not affect the potential of PK150 or related N,N'-diaryl urea compounds as new antibiotic drug candidates against multidrug-resistant infections.
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18
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Qu D, Hou Z, Li J, Luo L, Su S, Ye Z, Bai Y, Zhang X, Chen G, Li Z, Wang Y, Xue X, Luo X, Li M. A new coumarin compound DCH combats methicillin-resistant Staphylococcus aureus biofilm by targeting arginine repressor. SCIENCE ADVANCES 2020; 6:eaay9597. [PMID: 32832655 PMCID: PMC7439407 DOI: 10.1126/sciadv.aay9597] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 06/05/2020] [Indexed: 05/26/2023]
Abstract
Staphylococcus aureus infection is difficult to eradicate because of biofilm formation and antibiotic resistance. The increasing prevalence of methicillin-resistant Staphylococcus aureus (MRSA) infection necessitates the development of a new agent against bacterial biofilms. We report a new coumarin compound, termed DCH, that effectively combats MRSA in vitro and in vivo and exhibits potent antibiofilm activity without detectable resistance. Cellular proteome analysis suggests that the molecular mechanism of action of DCH involves the arginine catabolic pathway. Using molecular docking and binding affinity assays of DCH, and comparison of the properties of wild-type and ArgR-deficient MRSA strains, we demonstrate that the arginine repressor ArgR, an essential regulator of the arginine catabolic pathway, is the target of DCH. These findings indicate that DCH is a promising lead compound and validate bacterial ArgR as a potential target in the development of new drugs against MRSA biofilms.
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Affiliation(s)
- Di Qu
- Department of Pharmacology, School of Pharmacy, The Fourth Military Medical University, Xi’an 710032, China
| | - Zheng Hou
- Department of Pharmacology, School of Pharmacy, The Fourth Military Medical University, Xi’an 710032, China
| | - Jing Li
- Key Laboratory for Surface Engineering and Remanufacturing in Shaanxi province, School of Chemical Engineering, Xi’an University, Xi’an 710065, China
| | - Liyang Luo
- Department of Pharmacology, School of Pharmacy, The Fourth Military Medical University, Xi’an 710032, China
| | - Shan Su
- Department of Pharmacology, School of Pharmacy, The Fourth Military Medical University, Xi’an 710032, China
| | - Zichen Ye
- Department of Pharmacogenomics, School of Pharmacy, The Fourth Military Medical University, Xi’an 710032, China
| | - Yinlan Bai
- Department of Microbiology, School of Basic Medicine, The Fourth Military Medical University, Xi’an 710032, China
| | - Xinlei Zhang
- Department of Medical Chemistry, School of Pharmacy, The Fourth Military Medical University, Xi’an 710032, China
| | - Guanghui Chen
- Department of Pharmacology, School of Pharmacy, The Fourth Military Medical University, Xi’an 710032, China
| | - Zhoupeng Li
- Department of Pharmacology, School of Pharmacy, The Fourth Military Medical University, Xi’an 710032, China
| | - Yikun Wang
- Department of Pharmacology, School of Pharmacy, The Fourth Military Medical University, Xi’an 710032, China
| | - Xiaoyan Xue
- Department of Pharmacology, School of Pharmacy, The Fourth Military Medical University, Xi’an 710032, China
| | - Xiaoxing Luo
- Department of Pharmacology, School of Pharmacy, The Fourth Military Medical University, Xi’an 710032, China
| | - Mingkai Li
- Department of Pharmacology, School of Pharmacy, The Fourth Military Medical University, Xi’an 710032, China
- Precision Pharmacy and Drug Development Center, The Fourth Military Medical University, Xi’an 710032, China
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19
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Mariutti RB, Hernández-González JE, Nascimento AFZ, de Morais MAB, Murakami MT, Carareto CMA, Arni RK. A single P115Q mutation modulates specificity in the Corynebacterium pseudotuberculosis arginine repressor. Biochim Biophys Acta Gen Subj 2020; 1864:129597. [PMID: 32156582 DOI: 10.1016/j.bbagen.2020.129597] [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: 10/02/2019] [Revised: 03/02/2020] [Accepted: 03/03/2020] [Indexed: 11/28/2022]
Abstract
The arginine repressor (ArgR) regulates the expression of genes involved in arginine biosynthesis. Upon attaining a threshold concentration of arginine in the cytoplasm, the trimeric C-terminal domain of ArgR binds three arginines in a shallow surface cleft and subsequently hexamerizes forming a dimer of trimers containing six Arg co-repressor molecules which are buried at the subunit interfaces. The N-terminal domains of this complex bind to the DNA promoter thereby interrupting the transcription of the genes related to Arg biosynthesis. The crystal structures of the wild type and mutant Pro115Gln ArgR from Corynebacterium pseudotuberculosis determined at 1.7 Å demonstrate that a single amino acid substitution switches co-repressor specificity from Tyr to Arg. Molecular dynamics simulations indicate that the first step, i.e., the binding of the co-repressor, occurs in the trimeric state and that Pro115Gln ArgR preferentially binds Arg. It was also shown that, in Pro115 ArgR hexamers, the concomitant binding of sodium ions shifts selectivity to Tyr. Structural data combined with phylogenetic analyses of ArgR from C. pseudotuberculosis suggest that substitutions in the binding pocket at position 115 may alter its specificity for amino acids and that the length of the protein interdomain linker can provide further functional flexibility. These results support the existence of alternative ArgR regulatory mechanisms in this pathogenic bacterium.
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Affiliation(s)
- Ricardo B Mariutti
- Multiuser Center for Biomolecular Innovation, IBILCE/UNESP, São José do Rio Preto, SP, Brazil.
| | | | - Andrey F Z Nascimento
- Brazilian Synchrotron Light Laboratory (LNLS), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP, Brazil
| | - Mariana A B de Morais
- Brazilian Synchrotron Light Laboratory (LNLS), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP, Brazil
| | - Mario T Murakami
- Brazilian Synchrotron Light Laboratory (LNLS), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP, Brazil
| | - Claudia M A Carareto
- Laboratory of Molecular Evolution IBILCE/UNESP, São José do Rio Preto, SP, Brazil
| | - Raghuvir K Arni
- Multiuser Center for Biomolecular Innovation, IBILCE/UNESP, São José do Rio Preto, SP, Brazil; Department of Physics, IBILCE/UNESP, São José do Rio Preto, SP, Brazil
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20
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Le P, Kunold E, Macsics R, Rox K, Jennings MC, Ugur I, Reinecke M, Chaves-Moreno D, Hackl MW, Fetzer C, Mandl FAM, Lehmann J, Korotkov VS, Hacker SM, Kuster B, Antes I, Pieper DH, Rohde M, Wuest WM, Medina E, Sieber SA. Repurposing human kinase inhibitors to create an antibiotic active against drug-resistant Staphylococcus aureus, persisters and biofilms. Nat Chem 2020; 12:145-158. [PMID: 31844194 PMCID: PMC6994260 DOI: 10.1038/s41557-019-0378-7] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 10/15/2019] [Indexed: 12/31/2022]
Abstract
New drugs are desperately needed to combat methicillin-resistant Staphylococcus aureus (MRSA) infections. Here, we report screening commercial kinase inhibitors for antibacterial activity and found the anticancer drug sorafenib as major hit that effectively kills MRSA strains. Varying the key structural features led to the identification of a potent analogue, PK150, that showed antibacterial activity against several pathogenic strains at submicromolar concentrations. Furthermore, this antibiotic eliminated challenging persisters as well as established biofilms. PK150 holds promising therapeutic potential as it did not induce in vitro resistance, and shows oral bioavailability and in vivo efficacy. Analysis of the mode of action using chemical proteomics revealed several targets, which included interference with menaquinone biosynthesis by inhibiting demethylmenaquinone methyltransferase and the stimulation of protein secretion by altering the activity of signal peptidase IB. Reduced endogenous menaquinone levels along with enhanced levels of extracellular proteins of PK150-treated bacteria support this target hypothesis. The associated antibiotic effects, especially the lack of resistance development, probably stem from the compound's polypharmacology.
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Affiliation(s)
- Philipp Le
- Center for Integrated Protein Science at the Department of Chemistry, Technische Universität München, Garching bei München, Germany
- Chair of Organic Chemistry II, Technische Universität München, Garching bei München, Germany
| | - Elena Kunold
- Center for Integrated Protein Science at the Department of Chemistry, Technische Universität München, Garching bei München, Germany
- Chair of Organic Chemistry II, Technische Universität München, Garching bei München, Germany
- SciLifeLab, Department of Oncology-Pathology, Karolinska Institutet, Solna, Sweden
| | - Robert Macsics
- Center for Integrated Protein Science at the Department of Chemistry, Technische Universität München, Garching bei München, Germany
- Chair of Organic Chemistry II, Technische Universität München, Garching bei München, Germany
| | - Katharina Rox
- Department of Chemical Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
- German Centre for Infection Research, Partner Site Braunschweig-Hannover, Hannover, Germany
| | - Megan C Jennings
- Department of Chemistry, Temple University, Philadelphia, PA, USA
| | - Ilke Ugur
- Center for Integrated Protein Science, TUM School of Life Sciences, Technische Universität München, Freising, Germany
| | - Maria Reinecke
- Chair of Proteomics and Bioanalytics, Technische Universität München, Freising, Germany
- German Cancer Consortium, Partner Site Munich, Munich, Germany
- German Cancer Research Center, Heidelberg, Germany
| | - Diego Chaves-Moreno
- Microbial Interactions and Processes Research Group, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Mathias W Hackl
- Center for Integrated Protein Science at the Department of Chemistry, Technische Universität München, Garching bei München, Germany
- Chair of Organic Chemistry II, Technische Universität München, Garching bei München, Germany
| | - Christian Fetzer
- Center for Integrated Protein Science at the Department of Chemistry, Technische Universität München, Garching bei München, Germany
- Chair of Organic Chemistry II, Technische Universität München, Garching bei München, Germany
| | - Franziska A M Mandl
- Center for Integrated Protein Science at the Department of Chemistry, Technische Universität München, Garching bei München, Germany
- Chair of Organic Chemistry II, Technische Universität München, Garching bei München, Germany
| | - Johannes Lehmann
- Center for Integrated Protein Science at the Department of Chemistry, Technische Universität München, Garching bei München, Germany
- Chair of Organic Chemistry II, Technische Universität München, Garching bei München, Germany
| | - Vadim S Korotkov
- Center for Integrated Protein Science at the Department of Chemistry, Technische Universität München, Garching bei München, Germany
- Chair of Organic Chemistry II, Technische Universität München, Garching bei München, Germany
| | - Stephan M Hacker
- Department of Chemistry, Technische Universität München, Garching bei München, Germany
| | - Bernhard Kuster
- Chair of Proteomics and Bioanalytics, Technische Universität München, Freising, Germany
- German Cancer Consortium, Partner Site Munich, Munich, Germany
- German Cancer Research Center, Heidelberg, Germany
- Center for Integrated Protein Science Munich, Garching bei München, Germany
| | - Iris Antes
- Center for Integrated Protein Science, TUM School of Life Sciences, Technische Universität München, Freising, Germany
| | - Dietmar H Pieper
- Microbial Interactions and Processes Research Group, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Manfred Rohde
- Central Facility for Microscopy, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - William M Wuest
- Department of Chemistry, Emory University, Atlanta, GA, USA
- Emory Antibiotic Resistance Center, Emory School of Medicine, Atlanta, GA, USA
| | - Eva Medina
- Infection Immunology Research Group, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Stephan A Sieber
- Center for Integrated Protein Science at the Department of Chemistry, Technische Universität München, Garching bei München, Germany.
- Chair of Organic Chemistry II, Technische Universität München, Garching bei München, Germany.
- Helmholtz Institute for Pharmaceutical Research Saarland, Helmholtz Centre for Infection Research, Saarbrücken, Germany.
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21
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Kang S, Kong F, Liang X, Li M, Yang N, Cao X, Yang M, Tao D, Yue X, Zheng Y. Label-Free Quantitative Proteomics Reveals the Multitargeted Antibacterial Mechanisms of Lactobionic Acid against Methicillin-Resistant Staphylococcus aureus (MRSA) using SWATH-MS Technology. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:12322-12332. [PMID: 31638792 DOI: 10.1021/acs.jafc.9b06364] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The objective of the present study was to reveal the antibacterial mechanism of lactobionic acid (LBA) against methicillin-resistant Staphylococcus aureus (MRSA) using quantitative proteomics by sequential window acquisition of all theoretical mass spectra (SWATH-MS) to analyze 100 differentially expressed proteins after LBA treatment. Furthermore, multiple experiments were conducted to validate the results of the proteomic analysis including reactive oxygen species (ROS), virulence-associated gene expression, and the relative quantification of target proteins and genes by parallel reaction monitoring and quantitative real-time PCR. Combining the ultrastructure observations, proteomic analysis, and our previous research, the mode of LBA action against MRSA was speculated as cell wall damage and loss of membrane integrity; inhibition of DNA repair and protein synthesis; inhibition of virulence factors and biofilm production; induction of oxidative stress; and inhibition of metabolic pathways. These results suggest potential applications for LBA in food safety and pharmaceuticals, considering its multitarget effects against MRSA.
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Affiliation(s)
- Shimo Kang
- College of Food Science , Shenyang Agricultural University , No. 120 Dongling Road , Shenyang , Liaoning 110161 , P.R. China
| | - Fanhua Kong
- College of Food Science , Shenyang Agricultural University , No. 120 Dongling Road , Shenyang , Liaoning 110161 , P.R. China
| | - Xiaona Liang
- College of Food Science , Shenyang Agricultural University , No. 120 Dongling Road , Shenyang , Liaoning 110161 , P.R. China
| | - Mohan Li
- College of Food Science , Shenyang Agricultural University , No. 120 Dongling Road , Shenyang , Liaoning 110161 , P.R. China
| | - Ning Yang
- College of Food Science , Shenyang Agricultural University , No. 120 Dongling Road , Shenyang , Liaoning 110161 , P.R. China
| | - Xueyan Cao
- College of Food Science , Shenyang Agricultural University , No. 120 Dongling Road , Shenyang , Liaoning 110161 , P.R. China
| | - Mei Yang
- College of Food Science , Shenyang Agricultural University , No. 120 Dongling Road , Shenyang , Liaoning 110161 , P.R. China
| | - Dongbing Tao
- College of Food Science , Shenyang Agricultural University , No. 120 Dongling Road , Shenyang , Liaoning 110161 , P.R. China
| | - Xiqing Yue
- College of Food Science , Shenyang Agricultural University , No. 120 Dongling Road , Shenyang , Liaoning 110161 , P.R. China
| | - Yan Zheng
- College of Food Science , Shenyang Agricultural University , No. 120 Dongling Road , Shenyang , Liaoning 110161 , P.R. China
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22
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Loss G, Simões PM, Valour F, Cortês MF, Gonzaga L, Bergot M, Trouillet-Assant S, Josse J, Diot A, Ricci E, Vasconcelos AT, Laurent F. Staphylococcus aureus Small Colony Variants (SCVs): News From a Chronic Prosthetic Joint Infection. Front Cell Infect Microbiol 2019; 9:363. [PMID: 31696062 PMCID: PMC6817495 DOI: 10.3389/fcimb.2019.00363] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 10/07/2019] [Indexed: 12/21/2022] Open
Abstract
Small colony variants (SCV) of Staphylococcus aureus have been reported as implicated in chronic infections. Here, we investigated the genomic and transcriptomic changes involved in the evolution from a wild-type to a SCV from in a patient with prosthetic joint infection relapse. The SCV presented a stable phenotype with no classical auxotrophy and the emergence of rifampicin resistance. Whole Genome Sequencing (WGS) analysis showed only the loss of a 42.5 kb phage and 3 deletions, among which one targeting the rpoB gene, known to be the target of rifampicin and to be associated to SCV formation in the context of a constitutively active stringent response. Transcriptomic analysis highlighted a specific signature in the SCV strain including a complex, multi-level strategy of survival and adaptation to chronicity within the host including a protection from the inflammatory response, an evasion of the immune response, a constitutively activated stringent response and a scavenging of iron sources.
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Affiliation(s)
- Guilherme Loss
- Laboratório Nacional de Computação Científica, Rio de Janeiro, Brazil
| | - Patricia Martins Simões
- National Reference Center for Staphylococci - Hospices Civils de Lyon, IAI-Department of Clinical Microbiology, Northern Hospital Group, Lyon, France.,Centre International de Recherche en Infectiologie (CIRI), Lyon, France
| | - Florent Valour
- Centre International de Recherche en Infectiologie (CIRI), Lyon, France.,Hospices Civils de Lyon, Infectious Diseases Department, Northern Hospital Group, Lyon, France
| | - Marina Farrel Cortês
- Institute of Microbiology Professor Paulo de Góes, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Luiz Gonzaga
- Laboratório Nacional de Computação Científica, Rio de Janeiro, Brazil
| | - Marine Bergot
- Centre International de Recherche en Infectiologie (CIRI), Lyon, France
| | - Sophie Trouillet-Assant
- Hospices Civils de Lyon, Joint Research Unit HCL-BioMerieux, Centre Hospitalier Lyon Sud, Pierre-Benite, France
| | - Jêrome Josse
- Centre International de Recherche en Infectiologie (CIRI), Lyon, France
| | - Alan Diot
- Centre International de Recherche en Infectiologie (CIRI), Lyon, France
| | - Emiliano Ricci
- Centre International de Recherche en Infectiologie (CIRI), Lyon, France
| | | | - Frédéric Laurent
- National Reference Center for Staphylococci - Hospices Civils de Lyon, IAI-Department of Clinical Microbiology, Northern Hospital Group, Lyon, France.,Centre International de Recherche en Infectiologie (CIRI), Lyon, France
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23
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Dupre JM, Johnson WL, Ulanov AV, Li Z, Wilkinson BJ, Gustafson JE. Transcriptional profiling and metabolomic analysis of Staphylococcus aureus grown on autoclaved chicken breast. Food Microbiol 2019; 82:46-52. [DOI: 10.1016/j.fm.2019.01.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 12/21/2018] [Accepted: 01/11/2019] [Indexed: 10/27/2022]
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24
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Palma Medina LM, Becker AK, Michalik S, Yedavally H, Raineri EJM, Hildebrandt P, Gesell Salazar M, Surmann K, Pförtner H, Mekonnen SA, Salvati A, Kaderali L, van Dijl JM, Völker U. Metabolic Cross-talk Between Human Bronchial Epithelial Cells and Internalized Staphylococcus aureus as a Driver for Infection. Mol Cell Proteomics 2019; 18:892-908. [PMID: 30808728 DOI: 10.1074/mcp.ra118.001138] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 02/25/2019] [Indexed: 11/06/2022] Open
Abstract
Staphylococcus aureus is infamous for causing recurrent infections of the human respiratory tract. This is a consequence of its ability to adapt to different niches, including the intracellular milieu of lung epithelial cells. To understand the dynamic interplay between epithelial cells and the intracellular pathogen, we dissected their interactions over 4 days by mass spectrometry. Additionally, we investigated the dynamics of infection through live cell imaging, immunofluorescence and electron microscopy. The results highlight a major role of often overlooked temporal changes in the bacterial and host metabolism, triggered by fierce competition over limited resources. Remarkably, replicating bacteria reside predominantly within membrane-enclosed compartments and induce apoptosis of the host within ∼24 h post infection. Surviving infected host cells carry a subpopulation of non-replicating bacteria in the cytoplasm that persists. Altogether, we conclude that, besides the production of virulence factors by bacteria, it is the way in which intracellular resources are used, and how host and intracellular bacteria subsequently adapt to each other that determines the ultimate outcome of the infectious process.
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Affiliation(s)
- Laura M Palma Medina
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Mecklenburg-Vorpommern, Germany;; Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Ann-Kristin Becker
- Institute of Bioinformatics, University Medicine Greifswald, Greifswald, Mecklenburg-Vorpommern, Germany
| | - Stephan Michalik
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Mecklenburg-Vorpommern, Germany
| | - Harita Yedavally
- Division of Pharmacokinetics, Toxicology, and Targeting, Groningen Research Institute of Pharmacy, University of Groningen, Groningen, Groningen, The Netherlands
| | - Elisa J M Raineri
- Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Petra Hildebrandt
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Mecklenburg-Vorpommern, Germany
| | - Manuela Gesell Salazar
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Mecklenburg-Vorpommern, Germany
| | - Kristin Surmann
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Mecklenburg-Vorpommern, Germany
| | - Henrike Pförtner
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Mecklenburg-Vorpommern, Germany
| | - Solomon A Mekonnen
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Mecklenburg-Vorpommern, Germany;; Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Anna Salvati
- Division of Pharmacokinetics, Toxicology, and Targeting, Groningen Research Institute of Pharmacy, University of Groningen, Groningen, Groningen, The Netherlands
| | - Lars Kaderali
- Institute of Bioinformatics, University Medicine Greifswald, Greifswald, Mecklenburg-Vorpommern, Germany
| | - Jan Maarten van Dijl
- Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands;.
| | - Uwe Völker
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Mecklenburg-Vorpommern, Germany;.
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25
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Interplay of Nitric Oxide Synthase (NOS) and SrrAB in Modulation of Staphylococcus aureus Metabolism and Virulence. Infect Immun 2019; 87:IAI.00570-18. [PMID: 30420450 DOI: 10.1128/iai.00570-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 10/26/2018] [Indexed: 12/15/2022] Open
Abstract
Staphylococcus aureus nitric oxide synthase (saNOS) is a major contributor to virulence, stress resistance, and physiology, yet the specific mechanism(s) by which saNOS intersects with other known regulatory circuits is largely unknown. The SrrAB two-component system, which modulates gene expression in response to the reduced state of respiratory menaquinones, is a positive regulator of nos expression. Several SrrAB-regulated genes were also previously shown to be induced in an aerobically respiring nos mutant, suggesting a potential interplay between saNOS and SrrAB. Therefore, a combination of genetic, molecular, and physiological approaches was employed to characterize a nos srrAB mutant, which had significant reductions in the maximum specific growth rate and oxygen consumption when cultured under conditions promoting aerobic respiration. The nos srrAB mutant secreted elevated lactate levels, correlating with the increased transcription of lactate dehydrogenases. Expression of nitrate and nitrite reductase genes was also significantly enhanced in the nos srrAB double mutant, and its aerobic growth defect could be partially rescued with supplementation with nitrate, nitrite, or ammonia. Furthermore, elevated ornithine and citrulline levels and highly upregulated expression of arginine deiminase genes were observed in the double mutant. These data suggest that a dual deficiency in saNOS and SrrAB limits S. aureus to fermentative metabolism, with a reliance on nitrate assimilation and the urea cycle to help fuel energy production. The nos, srrAB, and nos srrAB mutants showed comparable defects in endothelial intracellular survival, whereas the srrAB and nos srrAB mutants were highly attenuated during murine sepsis, suggesting that SrrAB-mediated metabolic versatility is dominant in vivo.
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26
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Abouelhassan Y, Zhang Y, Jin S, Huigens RW. Transcript Profiling of MRSA Biofilms Treated with a Halogenated Phenazine Eradicating Agent: A Platform for Defining Cellular Targets and Pathways Critical to Biofilm Survival. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201809785] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Yasmeen Abouelhassan
- Department of Medicinal ChemistryCenter for Natural Products, Drug Discovery and Development (CNPD3)College of PharmacyUniversity of Florida 1345 Center Drive Gainesville FL USA
| | - Yanping Zhang
- Interdisciplinary Center for Biotechnology Research (ICBR)Gene Expression and GenotypingUniversity of Florida USA
| | - Shouguang Jin
- Department of Molecular Genetics and Microbiology, College of MedicineUniversity of Florida USA
| | - Robert W. Huigens
- Department of Medicinal ChemistryCenter for Natural Products, Drug Discovery and Development (CNPD3)College of PharmacyUniversity of Florida 1345 Center Drive Gainesville FL USA
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27
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Abouelhassan Y, Zhang Y, Jin S, Huigens RW. Transcript Profiling of MRSA Biofilms Treated with a Halogenated Phenazine Eradicating Agent: A Platform for Defining Cellular Targets and Pathways Critical to Biofilm Survival. Angew Chem Int Ed Engl 2018; 57:15523-15528. [PMID: 30230671 DOI: 10.1002/anie.201809785] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Indexed: 01/09/2023]
Abstract
Bacterial biofilms are surface-attached communities of non-replicating bacteria innately tolerant to antibiotics. Biofilms display differential gene expression profiles and physiologies as compared to their planktonic counterparts; however, their biology remains largely unknown. In this study, we used a halogenated phenazine (HP) biofilm eradicator in transcript profiling experiments (RNA-seq) to define cellular targets and pathways critical to biofilm viability. WoPPER analysis with time-course validation (RT-qPCR) revealed that HP-14 induces rapid iron starvation in MRSA biofilms, as evident by the activation of iron-acquisition gene clusters in 1 hour. Serine proteases and oligopeptide transporters were also found to be up-regulated, whereas glycolysis, arginine deiminase, and urease gene clusters were down-regulated. KEGG analysis revealed that HP-14 impacts metabolic and ABC transporter functional pathways. These findings suggest that MRSA biofilm viability relies on iron homeostasis.
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Affiliation(s)
- Yasmeen Abouelhassan
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy, University of Florida, 1345 Center Drive, Gainesville, FL, USA
| | - Yanping Zhang
- Interdisciplinary Center for Biotechnology Research (ICBR), Gene Expression and Genotyping, University of Florida, USA
| | - Shouguang Jin
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, USA
| | - Robert W Huigens
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy, University of Florida, 1345 Center Drive, Gainesville, FL, USA
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28
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Fernández L, González S, Quiles-Puchalt N, Gutiérrez D, Penadés JR, García P, Rodríguez A. Lysogenization of Staphylococcus aureus RN450 by phages ϕ11 and ϕ80α leads to the activation of the SigB regulon. Sci Rep 2018; 8:12662. [PMID: 30139986 PMCID: PMC6107660 DOI: 10.1038/s41598-018-31107-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 08/10/2018] [Indexed: 12/18/2022] Open
Abstract
Staphylococcus aureus is a major opportunistic pathogen that commonly forms biofilms on various biotic and abiotic surfaces. Also, most isolates are known to carry prophages in their genomes. With this in mind, it seems that acquiring a better knowledge of the impact of prophages on the physiology of S. aureus biofilm cells would be useful for developing strategies to eliminate this pathogen. Here, we performed RNA-seq analysis of biofilm cells formed by S. aureus RN450 and two derived strains carrying prophages ϕ11 and ϕ80α. The lysogenic strains displayed increased biofilm formation and production of the carotenoid pigment staphyloxanthin. These phenotypes could be partly explained by the differences in gene expression displayed by prophage-harboring strains, namely an activation of the alternative sigma factor (SigB) regulon and downregulation of genes controlled by the Agr quorum-sensing system, especially the decreased transcription of genes encoding dispersion factors like proteases. Nonetheless, spontaneous lysis of part of the population could also contribute to the increased attached biomass. Interestingly, it appears that the phage CI protein plays a role in orchestrating these phage-host interactions, although more research is needed to confirm this possibility. Likewise, future studies should examine the impact of these two prophages during the infection.
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Affiliation(s)
- Lucía Fernández
- Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n 33300 -, Villaviciosa, Asturias, Spain.
| | - Silvia González
- Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n 33300 -, Villaviciosa, Asturias, Spain
| | - Nuria Quiles-Puchalt
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8TA, Glasgow, UK
| | - Diana Gutiérrez
- Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n 33300 -, Villaviciosa, Asturias, Spain
| | - José R Penadés
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8TA, Glasgow, UK
| | - Pilar García
- Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n 33300 -, Villaviciosa, Asturias, Spain
| | - Ana Rodríguez
- Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n 33300 -, Villaviciosa, Asturias, Spain
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29
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Liu W, Rochat T, Toffano-Nioche C, Le Lam TN, Bouloc P, Morvan C. Assessment of Bona Fide sRNAs in Staphylococcus aureus. Front Microbiol 2018. [PMID: 29515534 PMCID: PMC5826253 DOI: 10.3389/fmicb.2018.00228] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Bacterial regulatory RNAs have been extensively studied for over a decade, and are progressively being integrated into the complex genetic regulatory network. Transcriptomic arrays, recent deep-sequencing data and bioinformatics suggest that bacterial genomes produce hundreds of regulatory RNAs. However, while some have been authenticated, the existence of the others varies according to strains and growth conditions, and their detection fluctuates with the methodologies used for data acquisition and interpretation. For example, several small RNA (sRNA) candidates are now known to be parts of UTR transcripts. Accurate annotation of regulatory RNAs is a complex task essential for molecular and functional studies. We defined bona fide sRNAs as those that (i) likely act in trans and (ii) are not expressed from the opposite strand of a coding gene. Using published data and our own RNA-seq data, we reviewed hundreds of Staphylococcus aureus putative regulatory RNAs using the DETR'PROK computational pipeline and visual inspection of expression data, addressing the question of which transcriptional signals correspond to sRNAs. We conclude that the model strain HG003, a NCTC8325 derivative commonly used for S. aureus genetic regulation studies, has only about 50 bona fide sRNAs, indicating that these RNAs are less numerous than commonly stated. Among them, about half are associated to the S. aureus sp. core genome and a quarter are possibly expressed in other Staphylococci. We hypothesize on their features and regulation using bioinformatic approaches.
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Affiliation(s)
- Wenfeng Liu
- Institute for Integrative Biology of the Cell (I2BC), CEA, Centre National de la Recherche Scientifique, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Tatiana Rochat
- VIM, Institut National de la Recherche Agronomique, Université Paris-Saclay, Institut National de la Recherche Agronomique Centre Jouy-en-Josas, Jouy-en-Josas, France
| | - Claire Toffano-Nioche
- Institute for Integrative Biology of the Cell (I2BC), CEA, Centre National de la Recherche Scientifique, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Thao Nguyen Le Lam
- Institute for Integrative Biology of the Cell (I2BC), CEA, Centre National de la Recherche Scientifique, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Philippe Bouloc
- Institute for Integrative Biology of the Cell (I2BC), CEA, Centre National de la Recherche Scientifique, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Claire Morvan
- Institute for Integrative Biology of the Cell (I2BC), CEA, Centre National de la Recherche Scientifique, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
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30
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Choe D, Szubin R, Dahesh S, Cho S, Nizet V, Palsson B, Cho BK. Genome-scale analysis of Methicillin-resistant Staphylococcus aureus USA300 reveals a tradeoff between pathogenesis and drug resistance. Sci Rep 2018; 8:2215. [PMID: 29396540 PMCID: PMC5797083 DOI: 10.1038/s41598-018-20661-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 01/18/2018] [Indexed: 12/15/2022] Open
Abstract
Staphylococcus aureus infection is a rising public health care threat. S. aureus is believed to have elaborate regulatory networks that orchestrate its virulence. Despite its importance, the systematic understanding of the transcriptional landscape of S. aureus is limited. Here, we describe the primary transcriptome landscape of an epidemic USA300 isolate of community-acquired methicillin-resistant S. aureus. We experimentally determined 1,861 transcription start sites with their principal promoter elements, including well-conserved -35 and -10 elements and weakly conserved -16 element and 5' untranslated regions containing AG-rich Shine-Dalgarno sequence. In addition, we identified 225 genes whose transcription was initiated from multiple transcription start sites, suggesting potential regulatory functions at transcription level. Along with the transcription unit architecture derived by integrating the primary transcriptome analysis with operon prediction, the measurement of differential gene expression revealed the regulatory framework of the virulence regulator Agr, the SarA-family transcriptional regulators, and β-lactam resistance regulators. Interestingly, we observed a complex interplay between virulence regulation, β-lactam resistance, and metabolism, suggesting a possible tradeoff between pathogenesis and drug resistance in the USA300 strain. Our results provide platform resource for the location of transcription initiation and an in-depth understanding of transcriptional regulation of pathogenesis, virulence, and antibiotic resistance in S. aureus.
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Affiliation(s)
- Donghui Choe
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - Richard Szubin
- Department of Bioengineering, University of California San Diego, La Jolla, 92023, CA, USA
| | - Samira Dahesh
- University of California San Diego School of Medicine, La Jolla, 92023, CA, USA
| | - Suhyung Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
- KI for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - Victor Nizet
- University of California San Diego School of Medicine, La Jolla, 92023, CA, USA.
| | - Bernhard Palsson
- Department of Bioengineering, University of California San Diego, La Jolla, 92023, CA, USA.
- University of California San Diego School of Medicine, La Jolla, 92023, CA, USA.
| | - Byung-Kwan Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea.
- KI for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea.
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31
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Viçosa GN, Botta C, Ferrocino I, Bertolino M, Ventura M, Nero LA, Cocolin L. Staphylococcus aureus undergoes major transcriptional reorganization during growth with Enterococcus faecalis in milk. Food Microbiol 2018. [PMID: 29526203 DOI: 10.1016/j.fm.2018.01.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Previous studies have demonstrated the antagonistic potential of lactic acid bacteria (LAB) present in raw milk microbiota over Staphylococcus aureus, albeit the molecular mechanisms underlying this inhibitory effect are not fully understood. In this study, we compared the behavior of S. aureus ATCC 29213 alone and in the presence of a cheese-isolated LAB strain, Enterococcus faecalis 41FL1 in skimmed milk at 30 °C for 24 h using phenotypical and molecular approaches. Phenotypic analysis showed the absence of classical staphylococcal enterotoxins in co-culture with a 1.2-log decrease in S. aureus final population compared to single culture. Transcriptional activity of several exotoxins and global regulators, including agr, was negatively impacted in co-culture, contrasting with the accumulation of transcripts coding for surface proteins. After 24 h, the number of transcripts coding for several metabolite responsive elements, as well as enzymes involved in glycolysis and acetoin metabolism was increased in co-culture. The present study discusses the complexity of the transcriptomic mechanisms possibly leading to S. aureus attenuated virulence in the presence of E. faecalis and provides insights into this interspecies interaction in a simulated food context.
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Affiliation(s)
| | - Cristian Botta
- Department of Agricultural, Forest and Food Sciences, University of Turin, Grugliasco, Italy
| | - Ilario Ferrocino
- Department of Agricultural, Forest and Food Sciences, University of Turin, Grugliasco, Italy
| | - Marta Bertolino
- Department of Agricultural, Forest and Food Sciences, University of Turin, Grugliasco, Italy
| | - Marco Ventura
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma, Italy
| | - Luís Augusto Nero
- Department of Veterinary, Federal University of Viçosa, Viçosa, Brazil.
| | - Luca Cocolin
- Department of Agricultural, Forest and Food Sciences, University of Turin, Grugliasco, Italy.
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32
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Formation of Staphylococcus aureus Biofilm in the Presence of Sublethal Concentrations of Disinfectants Studied via a Transcriptomic Analysis Using Transcriptome Sequencing (RNA-seq). Appl Environ Microbiol 2017; 83:AEM.01643-17. [PMID: 29030437 DOI: 10.1128/aem.01643-17] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 10/02/2017] [Indexed: 01/25/2023] Open
Abstract
Staphylococcus aureus is a common biofilm-forming pathogen. Low doses of disinfectants have previously been reported to promote biofilm formation and to increase virulence. The aim of this study was to use transcriptome sequencing (RNA-seq) analysis to investigate global transcriptional changes in S. aureus in response to sublethal concentrations of the commonly used food industry disinfectants ethanol (EtOH) and chloramine T (ChT) and their combination (EtOH_ChT) in order to better understand the effects of these agents on biofilm formation. Treatment with EtOH and EtOH_ChT resulted in more significantly altered expression profiles than treatment with ChT. Our results revealed that EtOH and EtOH_ChT treatments enhanced the expression of genes responsible for regulation of gene expression (sigB), cell surface factors (clfAB), adhesins (sdrDE), and capsular polysaccharides (cap8EFGL), resulting in more intact biofilm. In addition, in this study we were able to identify the pathways involved in the adaptation of S. aureus to the stress of ChT treatment. Further, EtOH suppressed the effect of ChT on gene expression when these agents were used together at sublethal concentrations. These data show that in the presence of sublethal concentrations of tested disinfectants, S. aureus cells trigger protective mechanisms and try to cope with them.IMPORTANCE So far, the effect of disinfectants is not satisfactorily explained. The presented data will allow a better understanding of the mode of disinfectant action with regard to biofilm formation and the ability of bacteria to survive the treatment. Such an understanding could contribute to the effort to eliminate possible sources of bacteria, making disinfectant application as efficient as possible. Biofilm formation plays significant role in the spread and pathogenesis of bacterial species.
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33
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Rozo ZLC, Márquez-Ortiz RA, Castro BE, Gómez NV, Escobar-Pérez J. Participation of the arcRACME protein in self-activation of the arc operon located in the arginine catabolism mobile element in pandemic clone USA300. Mem Inst Oswaldo Cruz 2017; 112:499-503. [PMID: 28591311 PMCID: PMC5452487 DOI: 10.1590/0074-02760160424] [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: 09/19/2016] [Accepted: 03/04/2017] [Indexed: 11/21/2022] Open
Abstract
Staphylococcus aureus pandemic clone USA300 has, in addition to its constitutive arginine catabolism (arc) gene cluster, an arginine catabolism mobile element (ACME) carrying another such cluster, which gives this clone advantages in colonisation and infection. Gene arcR, which encodes an oxygen-sensitive transcriptional regulator, is inside ACME and downstream of the constitutive arc gene cluster, and this situation may have an impact on its activation. Different relative expression behaviours are proven here for arcRACME and the arcACME operon compared to the constitutive ones. We also show that the artificially expressed recombinant ArcRACME protein binds to the promoter region of the arcACME operon; this mechanism can be related to a positive feedback model, which may be responsible for increased anaerobic survival of the USA300 clone during infection-related processes.
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34
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Sánchez Mainar M, Matheuse F, De Vuyst L, Leroy F. Effects of glucose and oxygen on arginine metabolism by coagulase-negative staphylococci. Food Microbiol 2017; 65:170-178. [PMID: 28399999 DOI: 10.1016/j.fm.2017.02.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 02/10/2017] [Accepted: 02/15/2017] [Indexed: 12/01/2022]
Abstract
Coagulase-negative staphylococci (CNS) are not only part of the desirable microbiota of fermented meat products but also commonly inhabit skin and flesh wounds. Their proliferation depends on the versatility to use energy sources and the adaptation to fluctuating environmental parameters. In this study, the conversion of the amino acid arginine by two strains with arginine deiminase (ADI) activity (Staphylococcus carnosus 833 and S. pasteuri αs3-13) and a strain with nitric oxide synthase (NOS) activity (S. haemolyticus G110) was modelled as a function of glucose and oxygen availability. Both factors moderately inhibited the ADI-based conversion kinetics, never leading to full repression. However, for NOS-driven conversion of arginine by S. haemolyticus G110, oxygen was an absolute requirement. When changing from microaerobic conditions to aerobiosis, a switch from homolactic fermentation to a combined formation of lactic acid, acetic acid, and acetoin was found in all cases, after which lactic acid and acetic acid were used as substrates. The kinetic model proposed provided a suitable description of the data of glucose and arginine co-metabolism as a function of oxygen levels and may serve as a tool to further analyse the behaviour of staphylococci in different ecosystems or when applying specific food processing conditions.
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Affiliation(s)
- María Sánchez Mainar
- Research Group of Industrial Microbiology and Food Biotechnology (IMDO), Faculty of Sciences and Bio-engineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Fréderick Matheuse
- Research Group of Industrial Microbiology and Food Biotechnology (IMDO), Faculty of Sciences and Bio-engineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Luc De Vuyst
- Research Group of Industrial Microbiology and Food Biotechnology (IMDO), Faculty of Sciences and Bio-engineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Frédéric Leroy
- Research Group of Industrial Microbiology and Food Biotechnology (IMDO), Faculty of Sciences and Bio-engineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium.
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35
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Exploring the metabolic heterogeneity of coagulase-negative staphylococci to improve the quality and safety of fermented meats: a review. Int J Food Microbiol 2017; 247:24-37. [DOI: 10.1016/j.ijfoodmicro.2016.05.021] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 03/15/2016] [Accepted: 05/15/2016] [Indexed: 12/16/2022]
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36
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Thänert R, Goldmann O, Beineke A, Medina E. Host-inherent variability influences the transcriptional response of Staphylococcus aureus during in vivo infection. Nat Commun 2017; 8:14268. [PMID: 28155859 PMCID: PMC5296661 DOI: 10.1038/ncomms14268] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 12/14/2016] [Indexed: 12/11/2022] Open
Abstract
The rise of antibiotic resistance calls for alternative strategies to treat bacterial infections. One attractive strategy is to directly target bacterial virulence factors with anti-virulence drugs. The expression of virulence traits by pathogens is, however, not constitutive but rather induced by the level of stress encountered within the host. Here we use dual RNA sequencing (RNA-seq) to show that intrinsic variability in the level of host resistance greatly affects the pathogen's transcriptome in vivo. Through analysis of the transcriptional profiles of host and pathogen during Staphylococcus aureus infection of two mouse strains, shown to be susceptible (A/J) or resistant (C57BL/6) to the pathogen, we demonstrate that the expression of virulence factors is dependent on the encountered host resistance. We furthermore provide evidence that this dependence strongly influences the efficacy of anti-virulence strategies, highlighting a potential limitation for the implementation of these strategies. Drugs inhibiting virulence factors of bacterial pathogens are under development. Here, Thänert et al. analyse the transcriptomes of host and pathogen during Staphylococcus aureus infection of two mouse strains, and show that virulence determinants are differentially expressed in different mouse strains.
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Affiliation(s)
- Robert Thänert
- Infection Immunology Research Group, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Oliver Goldmann
- Infection Immunology Research Group, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Andreas Beineke
- Institute for Pathology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany
| | - Eva Medina
- Infection Immunology Research Group, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
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37
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Xiong L, Yang Y, Ye YN, Teng JLL, Chan E, Watt RM, Guo FB, Lau SKP, Woo PCY. Laribacter hongkongensis anaerobic adaptation mediated by arginine metabolism is controlled by the cooperation of FNR and ArgR. Environ Microbiol 2017; 19:1266-1280. [PMID: 28028888 DOI: 10.1111/1462-2920.13657] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 12/19/2016] [Accepted: 12/21/2016] [Indexed: 11/27/2022]
Abstract
Laribacter hongkongensis is a fish-borne pathogen associated with invasive infections and gastroenteritis. Its adaptive mechanisms to oxygen-limiting conditions in various environmental niches remain unclear. In this study, we compared the transcriptional profiles of L. hongkongensis under aerobic and anaerobic conditions using RNA-sequencing. Expression of genes involved in arginine metabolism significantly increased under anoxic conditions. Arginine was exploited as the sole energy source in L. hongkongensis for anaerobic respiration via the arginine catabolism pathway: specifically via the arginine deiminase (ADI) pathway. A transcriptional regulator FNR was identified to coordinate anaerobic metabolism by tightly regulating the expression of arginine metabolism genes. FNR executed its regulatory function by binding to FNR boxes in arc operons promoters. Survival of isogenic fnr mutant in macrophages decreased significantly when compared with wild-type; and expression level of fnr increased 8 h post-infection. Remarkably, FNR directly interacted with ArgR, another regulator that influences the biological fitness and intracellular survival of L. hongkongensis by regulating arginine metabolism genes. Our results demonstrated that FNR and ArgR work in coordination to respond to oxygen changes in both extracellular and intracellular environments, by finely regulating the ADI pathway and arginine anabolism pathways, thereby optimizing bacterial fitness in various environmental niches.
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Affiliation(s)
- Lifeng Xiong
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China.,Department of Microbiology, The University of Hong Kong, Hong Kong
| | - Ying Yang
- Department of Microbiology, The University of Hong Kong, Hong Kong
| | - Yuan-Nong Ye
- School of Biology and Engineering, Guizhou Medical University, Guizhou, China
| | - Jade L L Teng
- Department of Microbiology, The University of Hong Kong, Hong Kong.,Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong.,State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong.,Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong
| | - Elaine Chan
- Department of Microbiology, The University of Hong Kong, Hong Kong
| | - Rory M Watt
- Applied Oral Sciences, Faculty of Dentistry, The University of Hong Kong, Hong Kong
| | - Feng-Biao Guo
- Center of Bioinformatics, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Susanna K P Lau
- Department of Microbiology, The University of Hong Kong, Hong Kong.,Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong.,State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong.,Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong.,Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The University of Hong Kong, Hong Kong
| | - Patrick C Y Woo
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China.,Department of Microbiology, The University of Hong Kong, Hong Kong.,Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong.,State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong.,Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong.,Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The University of Hong Kong, Hong Kong
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38
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Zhang Y, Agrebi R, Bellows LE, Collet JF, Kaever V, Gründling A. Evolutionary Adaptation of the Essential tRNA Methyltransferase TrmD to the Signaling Molecule 3',5'-cAMP in Bacteria. J Biol Chem 2016; 292:313-327. [PMID: 27881678 PMCID: PMC5217690 DOI: 10.1074/jbc.m116.758896] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 11/21/2016] [Indexed: 11/06/2022] Open
Abstract
The nucleotide signaling molecule 3',5'-cyclic adenosine monophosphate (3',5'-cAMP) plays important physiological roles, ranging from carbon catabolite repression in bacteria to mediating the action of hormones in higher eukaryotes, including human. However, it remains unclear whether 3',5'-cAMP is universally present in the Firmicutes group of bacteria. We hypothesized that searching for proteins that bind 3',5'-cAMP might provide new insight into this question. Accordingly, we performed a genome-wide screen and identified the essential Staphylococcus aureus tRNA m1G37 methyltransferase enzyme TrmD, which is conserved in all three domains of life as a tight 3',5'-cAMP-binding protein. TrmD enzymes are known to use S-adenosyl-l-methionine (AdoMet) as substrate; we have shown that 3',5'-cAMP binds competitively with AdoMet to the S. aureus TrmD protein, indicating an overlapping binding site. However, the physiological relevance of this discovery remained unclear, as we were unable to identify a functional adenylate cyclase in S. aureus and only detected 2',3'-cAMP but not 3',5'-cAMP in cellular extracts. Interestingly, TrmD proteins from Escherichia coli and Mycobacterium tuberculosis, organisms known to synthesize 3',5'-cAMP, did not bind this signaling nucleotide. Comparative bioinformatics, mutagenesis, and biochemical analyses revealed that the highly conserved Tyr-86 residue in E. coli TrmD is essential to discriminate between 3',5'-cAMP and the native substrate AdoMet. Combined with a phylogenetic analysis, these results suggest that amino acids in the substrate binding pocket of TrmD underwent an adaptive evolution to accommodate the emergence of adenylate cyclases and thus the signaling molecule 3',5'-cAMP. Altogether this further indicates that S. aureus does not produce 3',5'-cAMP, which would otherwise competitively inhibit an essential enzyme.
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Affiliation(s)
- Yong Zhang
- From the Section of Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, United Kingdom
| | - Rym Agrebi
- WELBIO, Avenue Hippocrate 75, 1200 Brussels, Belgium.,de Duve Institute, Université Catholique de Louvain, Avenue Hippocrate 75, 1200 Brussels, Belgium, and
| | - Lauren E Bellows
- From the Section of Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, United Kingdom
| | - Jean-François Collet
- WELBIO, Avenue Hippocrate 75, 1200 Brussels, Belgium.,de Duve Institute, Université Catholique de Louvain, Avenue Hippocrate 75, 1200 Brussels, Belgium, and
| | - Volkhard Kaever
- Research Core Unit Metabolomics, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Angelika Gründling
- From the Section of Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, United Kingdom,
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39
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Xu T, Han J, Zhang J, Chen J, Wu N, Zhang W, Zhang Y. Absence of Protoheme IX Farnesyltransferase CtaB Causes Virulence Attenuation but Enhances Pigment Production and Persister Survival in MRSA. Front Microbiol 2016; 7:1625. [PMID: 27822202 PMCID: PMC5076432 DOI: 10.3389/fmicb.2016.01625] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 09/29/2016] [Indexed: 02/05/2023] Open
Abstract
The membrane protein CtaB in S. aureus is a protoheme IX farnesyltransferase involved in the synthesis of the heme containing terminal oxidases of bacterial respiratory chain. In this study, to assess the role of CtaB in S. aureus virulence, pigment production, and persister formation, we constructed a ctaB mutant in the methicillin-resistant Staphylococcus aureus (MRSA) strain USA500. We found that deletion of ctaB attenuated growth and virulence in mice but enhanced pigment production and formation of quinolone tolerant persister cells in stationary phase. RNA-seq analysis showed that deletion of ctaB caused decreased transcription of several virulence genes including RNAIII which is consistent with its virulence attenuation. In addition, transcription of 20 ribosomal genes and 24 genes involved in amino acid biosynthesis was significantly down-regulated in the ctaB knockout mutant compared with the parent strain. These findings suggest the importance of heme biosynthesis in virulence and persister formation of S. aureus.
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Affiliation(s)
- Tao Xu
- Key Laboratory of Medical Molecular Virology, Huashan Hospital, Shanghai Medical College of Fudan UniversityShanghai, China
| | - Jian Han
- Department of Pathogenic Biology, School of Basic Medical Sciences, Lanzhou UniversityLanzhou, China
| | - Jia Zhang
- Key Laboratory of Medical Molecular Virology, Huashan Hospital, Shanghai Medical College of Fudan UniversityShanghai, China
| | - Jiazhen Chen
- Key Laboratory of Medical Molecular Virology, Huashan Hospital, Shanghai Medical College of Fudan UniversityShanghai, China
| | - Nan Wu
- Key Laboratory of Medical Molecular Virology, Huashan Hospital, Shanghai Medical College of Fudan UniversityShanghai, China
| | - Wenhong Zhang
- Key Laboratory of Medical Molecular Virology, Huashan Hospital, Shanghai Medical College of Fudan UniversityShanghai, China
| | - Ying Zhang
- Key Laboratory of Medical Molecular Virology, Huashan Hospital, Shanghai Medical College of Fudan UniversityShanghai, China
- Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins UniversityBaltimore, MD, USA
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40
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FlpS, the FNR-Like Protein of Streptococcus suis Is an Essential, Oxygen-Sensing Activator of the Arginine Deiminase System. Pathogens 2016; 5:pathogens5030051. [PMID: 27455333 PMCID: PMC5039431 DOI: 10.3390/pathogens5030051] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 07/07/2016] [Accepted: 07/14/2016] [Indexed: 11/17/2022] Open
Abstract
Streptococcus (S.) suis is a zoonotic pathogen causing septicemia and meningitis in pigs and humans. During infection S. suis must metabolically adapt to extremely diverse environments of the host. CcpA and the FNR family of bacterial transcriptional regulators are important for metabolic gene regulation in various bacteria. The role of CcpA in S. suis is well defined, but the function of the FNR-like protein of S. suis, FlpS, is yet unknown. Transcriptome analyses of wild-type S. suis and a flpS mutant strain suggested that FlpS is involved in the regulation of the central carbon, arginine degradation and nucleotide metabolism. However, isotopologue profiling revealed no substantial changes in the core carbon and amino acid de novo biosynthesis. FlpS was essential for the induction of the arcABC operon of the arginine degrading pathway under aerobic and anaerobic conditions. The arcABC-inducing activity of FlpS could be associated with the level of free oxygen in the culture medium. FlpS was necessary for arcABC-dependent intracellular bacterial survival but redundant in a mice infection model. Based on these results, we propose that the core function of S. suis FlpS is the oxygen-dependent activation of the arginine deiminase system.
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41
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Zühlke D, Dörries K, Bernhardt J, Maaß S, Muntel J, Liebscher V, Pané-Farré J, Riedel K, Lalk M, Völker U, Engelmann S, Becher D, Fuchs S, Hecker M. Costs of life - Dynamics of the protein inventory of Staphylococcus aureus during anaerobiosis. Sci Rep 2016; 6:28172. [PMID: 27344979 PMCID: PMC4921807 DOI: 10.1038/srep28172] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 05/31/2016] [Indexed: 01/19/2023] Open
Abstract
Absolute protein quantification was applied to follow the dynamics of the cytoplasmic proteome of Staphylococcus aureus in response to long-term oxygen starvation. For 1,168 proteins, the majority of all expressed proteins, molecule numbers per cell have been determined to monitor the cellular investments in single branches of bacterial life for the first time. In the presence of glucose the anaerobic protein pattern is characterized by increased amounts of glycolytic and fermentative enzymes such as Eno, GapA1, Ldh1, and PflB. Interestingly, the ferritin-like protein FtnA belongs to the most abundant proteins during anaerobic growth. Depletion of glucose finally leads to an accumulation of different enzymes such as ArcB1, ArcB2, and ArcC2 involved in arginine deiminase pathway. Concentrations of 29 exo- and 78 endometabolites were comparatively assessed and have been integrated to the metabolic networks. Here we provide an almost complete picture on the response to oxygen starvation, from signal transduction pathways to gene expression pattern, from metabolic reorganization after oxygen depletion to beginning cell death and lysis after glucose exhaustion. This experimental approach can be considered as a proof of principle how to combine cell physiology with quantitative proteomics for a new dimension in understanding simple life processes as an entity.
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Affiliation(s)
- Daniela Zühlke
- Institute of Microbiology, Ernst-Moritz-Arndt-University Greifswald, F.-L.-Jahn-Strasse 15, D-17487 Greifswald, Germany
| | - Kirsten Dörries
- Institute of Biochemistry, Ernst-Moritz-Arndt-University Greifswald, Felix-Hausdorff-Strasse 4, D-17487 Greifswald, Germany
| | - Jörg Bernhardt
- Institute of Microbiology, Ernst-Moritz-Arndt-University Greifswald, F.-L.-Jahn-Strasse 15, D-17487 Greifswald, Germany
| | - Sandra Maaß
- Institute of Microbiology, Ernst-Moritz-Arndt-University Greifswald, F.-L.-Jahn-Strasse 15, D-17487 Greifswald, Germany
| | - Jan Muntel
- Institute of Microbiology, Ernst-Moritz-Arndt-University Greifswald, F.-L.-Jahn-Strasse 15, D-17487 Greifswald, Germany
| | - Volkmar Liebscher
- Department of Mathematics and Informatics, Ernst-Moritz-Arndt-University Greifswald, Walther-Rathenau-Strasse 47, D-17487 Greifswald, Germany
| | - Jan Pané-Farré
- Institute of Microbiology, Ernst-Moritz-Arndt-University Greifswald, F.-L.-Jahn-Strasse 15, D-17487 Greifswald, Germany
| | - Katharina Riedel
- Institute of Microbiology, Ernst-Moritz-Arndt-University Greifswald, F.-L.-Jahn-Strasse 15, D-17487 Greifswald, Germany
| | - Michael Lalk
- Institute of Biochemistry, Ernst-Moritz-Arndt-University Greifswald, Felix-Hausdorff-Strasse 4, D-17487 Greifswald, Germany
| | - Uwe Völker
- Interfaculty Institute for Genetics and Functional Genomics, Ernst-Moritz-Arndt-University Greifswald, F.-L.-Jahn-Strasse 15 a, D-17487 Greifswald, Germany
| | - Susanne Engelmann
- Institute of Microbiology, Ernst-Moritz-Arndt-University Greifswald, F.-L.-Jahn-Strasse 15, D-17487 Greifswald, Germany.,Institute of Microbiology, Technical University Braunschweig, Inhoffenstrasse 7, D-38124 Braunschweig, Germany.,Helmholtz Institute for Infection Research, Microbial Proteomics, Inhoffenstrasse 7, D-38124 Braunschweig, Germany
| | - Dörte Becher
- Institute of Microbiology, Ernst-Moritz-Arndt-University Greifswald, F.-L.-Jahn-Strasse 15, D-17487 Greifswald, Germany
| | - Stephan Fuchs
- Institute of Microbiology, Ernst-Moritz-Arndt-University Greifswald, F.-L.-Jahn-Strasse 15, D-17487 Greifswald, Germany.,Robert Koch Institute, FG13 Nosocomial Pathogens and Antibiotic Resistance, Burgstrasse 37, D-38855 Wernigerode, Germany
| | - Michael Hecker
- Institute of Microbiology, Ernst-Moritz-Arndt-University Greifswald, F.-L.-Jahn-Strasse 15, D-17487 Greifswald, Germany
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42
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Xu Y, Maltesen RG, Larsen LH, Schønheyder HC, Le VQ, Nielsen JL, Nielsen PH, Thomsen TR, Nielsen KL. In vivo gene expression in a Staphylococcus aureus prosthetic joint infection characterized by RNA sequencing and metabolomics: a pilot study. BMC Microbiol 2016; 16:80. [PMID: 27150914 PMCID: PMC4858865 DOI: 10.1186/s12866-016-0695-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 04/26/2016] [Indexed: 02/01/2023] Open
Abstract
Background Staphylococcus aureus gene expression has been sparsely studied in deep-sited infections in humans. Here, we characterized the staphylococcal transcriptome in vivo and the joint fluid metabolome in a prosthetic joint infection with an acute presentation using deep RNA sequencing and nuclear magnetic resonance spectroscopy, respectively. We compared our findings with the genome, transcriptome and metabolome of the S. aureus joint fluid isolate grown in vitro. Result From the transcriptome analysis we found increased expression of siderophore synthesis genes and multiple known virulence genes. The regulatory pattern of catabolic pathway genes indicated that the bacterial infection was sustained on amino acids, glycans and nucleosides. Upregulation of fermentation genes and the presence of ethanol in joint fluid indicated severe oxygen limitation in vivo. Conclusion This single case study highlights the capacity of combined transcriptome and metabolome analyses for elucidating the pathogenesis of prosthetic infections of major clinical importance. Electronic supplementary material The online version of this article (doi:10.1186/s12866-016-0695-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yijuan Xu
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajersvej 7H, 9220, Aalborg, Denmark.,The Danish Technological Institute, Life Science Division, Aarhus, Denmark
| | - Raluca Georgiana Maltesen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajersvej 7H, 9220, Aalborg, Denmark
| | - Lone Heimann Larsen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajersvej 7H, 9220, Aalborg, Denmark.,Department of Clinical Microbiology, Aalborg University Hospital, Aalborg, Denmark
| | - Henrik Carl Schønheyder
- Department of Clinical Microbiology, Aalborg University Hospital, Aalborg, Denmark.,Department of Clinical Medicine, Aalborg University Hospital, Aalborg, Denmark
| | - Vang Quy Le
- Section for Molecular Diagnostics, Department of Clinical Biochemistry, Aalborg University Hospital, Aalborg, Denmark
| | - Jeppe Lund Nielsen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajersvej 7H, 9220, Aalborg, Denmark
| | - Per Halkjær Nielsen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajersvej 7H, 9220, Aalborg, Denmark
| | - Trine Rolighed Thomsen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajersvej 7H, 9220, Aalborg, Denmark.,The Danish Technological Institute, Life Science Division, Aarhus, Denmark
| | - Kåre Lehmann Nielsen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajersvej 7H, 9220, Aalborg, Denmark.
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Novel Structures and Temporal Changes of Arginine Catabolic Mobile Elements in Methicillin-Resistant Staphylococcus aureus Genotypes ST5-MRSA-II and ST764-MRSA-II in Japan. Antimicrob Agents Chemother 2016; 60:3119-22. [PMID: 26856835 DOI: 10.1128/aac.02356-15] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 02/01/2016] [Indexed: 11/20/2022] Open
Abstract
Twenty-two of 1,103 methicillin-resistant Staphylococcus aureus (MRSA) isolates containing the type II staphylococcal cassette chromosome mec element (SCCmec) (collected in Hokkaido, Japan, from 2008 to 2011) harbored the arginine catabolic mobile element (ACME). Five genetic variations were identified in the ACME-staphylococcal cassette chromosome mec composite islands, 66 to 79 kb in size. The percentage of ACME carriage temporally increased from 0.85% to 4.5% in parallel with the emergence of shorter variants (66 to 72 kb). Shorter variants may have a selective advantage and accelerate the dissemination of ACME in Japanese MRSA.
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44
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Arginine Metabolism in Bacterial Pathogenesis and Cancer Therapy. Int J Mol Sci 2016; 17:363. [PMID: 26978353 PMCID: PMC4813224 DOI: 10.3390/ijms17030363] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 01/29/2016] [Accepted: 03/04/2016] [Indexed: 02/06/2023] Open
Abstract
Antibacterial resistance to infectious diseases is a significant global concern for health care organizations; along with aging populations and increasing cancer rates, it represents a great burden for government healthcare systems. Therefore, the development of therapies against bacterial infection and cancer is an important strategy for healthcare research. Pathogenic bacteria and cancer have developed a broad range of sophisticated strategies to survive or propagate inside a host and cause infection or spread disease. Bacteria can employ their own metabolism pathways to obtain nutrients from the host cells in order to survive. Similarly, cancer cells can dysregulate normal human cell metabolic pathways so that they can grow and spread. One common feature of the adaption and disruption of metabolic pathways observed in bacterial and cancer cell growth is amino acid pathways; these have recently been targeted as a novel approach to manage bacterial infections and cancer therapy. In particular, arginine metabolism has been illustrated to be important not only for bacterial pathogenesis but also for cancer therapy. Therefore, greater insights into arginine metabolism of pathogenic bacteria and cancer cells would provide possible targets for controlling of bacterial infection and cancer treatment. This review will summarize the recent progress on the relationship of arginine metabolism with bacterial pathogenesis and cancer therapy, with a particular focus on arginase and arginine deiminase pathways of arginine catabolism.
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45
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Spahich NA, Vitko NP, Thurlow LR, Temple B, Richardson AR. Staphylococcus aureus lactate- and malate-quinone oxidoreductases contribute to nitric oxide resistance and virulence. Mol Microbiol 2016; 100:759-73. [PMID: 26851155 DOI: 10.1111/mmi.13347] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/01/2016] [Indexed: 12/27/2022]
Abstract
Staphylococcus aureus is a Gram-positive pathogen that resists many facets of innate immunity including nitric oxide (NO·). Staphylococcus aureus NO-resistance stems from its ability to evoke a metabolic state that circumvents the negative effects of reactive nitrogen species. The combination of l-lactate and peptides promotes S. aureus growth at moderate NO-levels, however, neither nutrient alone suffices. Here, we investigate the staphylococcal malate-quinone and l-lactate-quinone oxidoreductases (Mqo and Lqo), both of which are critical during NO-stress for the combined utilization of peptides and l-lactate. We address the specific contributions of Lqo-mediated l-lactate utilization and Mqo-dependent amino acid consumption during NO-stress. We show that Lqo conversion of l-lactate to pyruvate is required for the formation of ATP, an essential energy source for peptide utilization. Thus, both Lqo and Mqo are essential for growth under these conditions making them attractive candidates for targeted therapeutics. Accordingly, we exploited a modelled Mqo/Lqo structure to define the catalytic and substrate-binding residues.We also compare the S. aureus Mqo/Lqo enzymes to their close relatives throughout the staphylococci and explore the substrate specificities of each enzyme. This study provides the initial characterization of the mechanism of action and the immunometabolic roles for a newly defined staphylococcal enzyme family.
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Affiliation(s)
- Nicole A Spahich
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Nicholas P Vitko
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Lance R Thurlow
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Brenda Temple
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Anthony R Richardson
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
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46
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Xiong L, Teng JLL, Watt RM, Liu C, Lau SKP, Woo PCY. Molecular characterization of arginine deiminase pathway in Laribacter hongkongensis and unique regulation of arginine catabolism and anabolism by multiple environmental stresses. Environ Microbiol 2015; 17:4469-83. [PMID: 25950829 DOI: 10.1111/1462-2920.12897] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 04/22/2015] [Accepted: 05/03/2015] [Indexed: 12/29/2022]
Abstract
The betaproteobacterium Laribacter hongkongensis is associated with invasive bacteremic infections and gastroenteritis. Its genome contains two adjacent arc gene cassettes (arc1 and arc2) under independent transcriptional control, which are essential for acid resistance. Laribacter hongkongensis also encodes duplicate copies of the argA and argB genes from the arginine biosynthesis pathway. We show that arginine enhances the transcription of arcA2 but suppresses arcA1 expression. We demonstrate that ArgR acts as a transcriptional regulator of the two arc operons through binding to ARG operator sites (ARG boxes). Upon temperature shift from 20°C to 37°C, arcA1 transcription is upregulated while arcA2, argA2, argB2 and argG are downregulated. The transcription of arcA1 and arcA2 are augmented under anaerobic and acidic conditions. The transcription levels of argA1, argA2, argB1, argB2 and argG are significantly increased under anaerobic and acidic conditions but are repressed by the addition of arginine. Deletion of argR significantly decreases bacterial survival in macrophages, while expression of both arc operons, argR and all five of the anabolic arg genes increases 8 h post-infection. Our results show that arginine catabolism in L. hongkongensis is finely regulated by controlling the transcription of two arc operons, whereas arginine anabolism is controlled by two copies of argA and argB.
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Affiliation(s)
- Lifeng Xiong
- Department of Microbiology, The University of Hong Kong, Hong Kong, China
| | - Jade L L Teng
- Department of Microbiology, The University of Hong Kong, Hong Kong, China.,Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong, China
| | - Rory M Watt
- Oral Biosciences, Faculty of Dentistry, The University of Hong Kong, Hong Kong, China
| | - Cuihua Liu
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Susanna K P Lau
- Department of Microbiology, The University of Hong Kong, Hong Kong, China.,Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong, China.,State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong, China.,Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong, China
| | - Patrick C Y Woo
- Department of Microbiology, The University of Hong Kong, Hong Kong, China.,Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong, China.,State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong, China.,Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong, China
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47
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The Role of Two-Component Signal Transduction Systems in Staphylococcus aureus Virulence Regulation. Curr Top Microbiol Immunol 2015; 409:145-198. [PMID: 26728068 DOI: 10.1007/82_2015_5019] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Staphylococcus aureus is a versatile, opportunistic human pathogen that can asymptomatically colonize a human host but can also cause a variety of cutaneous and systemic infections. The ability of S. aureus to adapt to such diverse environments is reflected in the presence of complex regulatory networks fine-tuning metabolic and virulence gene expression. One of the most widely distributed mechanisms is the two-component signal transduction system (TCS) which allows a pathogen to alter its gene expression profile in response to environmental stimuli. The simpler TCSs consist of only a transmembrane histidine kinase (HK) and a cytosolic response regulator. S. aureus encodes a total of 16 conserved pairs of TCSs that are involved in diverse signalling cascades ranging from global virulence gene regulation (e.g. quorum sensing by the Agr system), the bacterial response to antimicrobial agents, cell wall metabolism, respiration and nutrient sensing. These regulatory circuits are often interconnected and affect each other's expression, thus fine-tuning staphylococcal gene regulation. This manuscript gives an overview of the current knowledge of staphylococcal environmental sensing by TCS and its influence on virulence gene expression and virulence itself. Understanding bacterial gene regulation by TCS can give major insights into staphylococcal pathogenicity and has important implications for knowledge-based drug design and vaccine formulation.
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48
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Regulation of the arginine deiminase system by ArgR2 interferes with arginine metabolism and fitness of Streptococcus pneumoniae. mBio 2014; 5:mBio.01858-14. [PMID: 25538192 PMCID: PMC4278536 DOI: 10.1128/mbio.01858-14] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Streptococcus pneumoniae is auxotrophic for arginine, and molecular analysis of the pneumococcal genome showed that the gene encoding an arginine-ornithine antiporter (ArcD) is organized in a cluster together with the arcABC genes encoding the arginine deiminase system (ADS) of pneumococci. The ADS consists of the arginine deiminase (AD), the catabolic ornithine carbamoyltransferase (cOCT), and the carbamate kinase (CK). Pneumococcal genomes contain three ArgR-type regulators (ArgR1, ArgR2, and AhrC) that are supposed to be involved in the regulation of arginine metabolism. Here, we identified ArgR2 of TIGR4 as the regulator of the ADS and ArcD. ArgR2 binds to promoter sequences of the arc operon, and the deficiency of ArgR2 in TIGR4 abrogates expression of the ADS, including the arginine-ornithine antiporter ArcD. Intranasal infection of mice and real-time bioimaging revealed that deletion of the arcABCDT genes attenuates TIGR4. However, the acute-pneumonia model and coinfection experiments indicated that the arginine-ornithine antiporter ArcD is essential to maintain fitness, while the deficiency of ADS enzymes has a minor impact on pneumococcal fitness under in vivo conditions. Strikingly, argR2 mutant TIGR4 outcompeted the wild type in the respiratory tract, suggesting an increase in fitness and further regulatory functions of ArgR2. In contrast to TIGR4, other pneumococci, such as D39, lacking expression of ArgR2, constitutively express the ADS with a truncated nonfunctional AD. On the basis of these results, we propose that the arginine-ornithine antiporter is essential to maintain pneumococcal fitness and that the genes of the ADS cluster are positively regulated in a strain-specific manner by ArgR2. Pneumococci are the major etiologic agents of community-acquired pneumonia, causing more than 1.5 million deaths annually worldwide. These versatile pathogens are highly adapted to the nutrients provided by the host niches encountered. Physiological fitness is of major importance for colonization of the nasopharyngeal cavity and dissemination during invasive infections. This work identifies the regulator ArgR2 as the activator of the S. pneumoniae TIGR4 ADS and the arginine-ornithine transporter ArcD, which is needed for uptake of the essential amino acid arginine. Although ArgR2 activates ArcD expression and uptake of arginine is required to maintain pneumococcal fitness, the deficiency of ArgR2 increases TIGR4 virulence under in vivo conditions, suggesting that other factors regulated by ArgR2 counterbalance the reduced uptake of arginine by ArcD. Thus, this work illustrates that the physiological homeostasis of pneumococci is complex and that ArgR2 plays a key role in maintaining bacterial fitness.
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49
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Hanses F, Roux C, Dunman PM, Salzberger B, Lee JC. Staphylococcus aureus gene expression in a rat model of infective endocarditis. Genome Med 2014; 6:93. [PMID: 25392717 PMCID: PMC4228149 DOI: 10.1186/s13073-014-0093-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 10/20/2014] [Indexed: 01/04/2023] Open
Abstract
Background Diabetes mellitus is a frequent underlying comorbidity in patients with Staphylococcus aureus endocarditis, and it represents a risk factor for complications and a negative outcome. The pathogenesis of staphylococcal endocardial infections in diabetic hosts has been poorly characterized, and little is known about S. aureus gene expression in endocardial vegetations. Methods We utilized a rat model of experimental S. aureus endocarditis to compare the pathogenesis of staphylococcal infection in diabetic and nondiabetic hosts and to study the global S. aureus transcriptome in endocardial vegetations in vivo. Results Diabetic rats had higher levels of bacteremia and larger endocardial vegetations than nondiabetic control animals. Microarray analyses revealed that 61 S. aureus genes were upregulated in diabetic rats, and the majority of these bacterial genes were involved in amino acid and carbohydrate metabolism. When bacterial gene expression in vivo (diabetic or nondiabetic endocardial vegetations) was compared to in vitro growth conditions, higher in vivo expression of genes encoding toxins and proteases was observed. Additionally, genes involved in the production of adhesins, capsular polysaccharide, and siderophores, as well as in amino acid and carbohydrate transport and metabolism, were upregulated in endocardial vegetations. To test the contribution of selected upregulated genes to the pathogenesis of staphylococcal endocarditis, isogenic deletion mutants were utilized. A mutant defective in production of the siderophore staphyloferrin B was attenuated in the endocarditis model, whereas the virulence of a surface adhesin (ΔsdrCDE) mutant was similar to that of the parental S. aureus strain. Conclusions Our results emphasize the relevance of diabetes mellitus as a risk factor for infectious endocarditis and provide a basis for understanding gene expression during staphylococcal infections in vivo. Electronic supplementary material The online version of this article (doi:10.1186/s13073-014-0093-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Frank Hanses
- Channing Laboratory, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115 USA ; Department of Internal Medicine I, University Hospital Regensburg, Franz-Josef-Strauss Allee 11, Regensburg, 93049 Germany
| | - Christelle Roux
- Department of Microbiology and Immunology, University of Rochester, Rochester, NY 14642 USA
| | - Paul M Dunman
- Department of Microbiology and Immunology, University of Rochester, Rochester, NY 14642 USA
| | - Bernd Salzberger
- Department of Internal Medicine I, University Hospital Regensburg, Franz-Josef-Strauss Allee 11, Regensburg, 93049 Germany
| | - Jean C Lee
- Channing Laboratory, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115 USA
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50
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Fulde M, Willenborg J, Huber C, Hitzmann A, Willms D, Seitz M, Eisenreich W, Valentin-Weigand P, Goethe R. The arginine-ornithine antiporter ArcD contributes to biological fitness of Streptococcus suis. Front Cell Infect Microbiol 2014; 4:107. [PMID: 25161959 PMCID: PMC4129364 DOI: 10.3389/fcimb.2014.00107] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Accepted: 07/21/2014] [Indexed: 11/19/2022] Open
Abstract
The arginine-ornithine antiporter (ArcD) is part of the Arginine Deiminase System (ADS), a catabolic, energy-providing pathway found in a variety of different bacterial species, including the porcine zoonotic pathogen Streptococcus suis. The ADS has recently been shown to play a role in the pathogenicity of S. suis, in particular in its survival in host cells. The contribution of arginine and arginine transport mediated by ArcD, however, has yet to be clarified. In the present study, we showed by experiments using [U-13C6]arginine as a tracer molecule that S. suis is auxotrophic for arginine and that bacterial growth depends on the uptake of extracellular arginine. To further study the role of ArcD in arginine metabolism, we generated an arcD-specific mutant strain and characterized its growth compared to the wild-type (WT) strain, a virulent serotype 2 strain. The mutant strain showed a markedly reduced growth in chemically defined media supplemented with arginine when compared to the WT strain, suggesting that ArcD promotes arginine uptake. To further evaluate the in vivo relevance of ArcD, we studied the intracellular bacterial survival of the arcD mutant strain in an epithelial cell culture infection model. The mutant strain was substantially attenuated, and its reduced intracellular survival rate correlated with a lower ability to neutralize the acidified environment. Based on these results, we propose that ArcD, by its function as an arginine-ornithine antiporter, is important for supplying arginine as substrate of the ADS and, thereby, contributes to biological fitness and virulence of S. suis in the host.
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Affiliation(s)
- Marcus Fulde
- Department of Infectious Diseases, Institute for Microbiology, University of Veterinary Medicine Hannover, Germany ; Department of Medical Microbiology, Helmholtz Centre for Infection Research (HZI) Braunschweig, Germany
| | - Joerg Willenborg
- Department of Infectious Diseases, Institute for Microbiology, University of Veterinary Medicine Hannover, Germany
| | - Claudia Huber
- Lehrstuhl für Biochemie, Technische Universität München Garching, Germany
| | - Angela Hitzmann
- Department of Medical Microbiology, Helmholtz Centre for Infection Research (HZI) Braunschweig, Germany
| | - Daniela Willms
- Department of Infectious Diseases, Institute for Microbiology, University of Veterinary Medicine Hannover, Germany
| | - Maren Seitz
- Department of Infectious Diseases, Institute for Microbiology, University of Veterinary Medicine Hannover, Germany
| | | | - Peter Valentin-Weigand
- Department of Infectious Diseases, Institute for Microbiology, University of Veterinary Medicine Hannover, Germany
| | - Ralph Goethe
- Department of Infectious Diseases, Institute for Microbiology, University of Veterinary Medicine Hannover, Germany
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