1
|
Ahmed A, Kelly A, Leonard D, Saleem W, Bezrukov A, Efthymiou CG, Zaworotko MJ, Tiana D, Boyd A, Papatriantafyllopoulou C. Synthesis and characterisation of antimicrobial metal-organic frameworks as multi-drug carriers. Dalton Trans 2024; 53:11867-11875. [PMID: 38952206 DOI: 10.1039/d4dt01100g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/03/2024]
Abstract
Antibiotic resistance is a significant global concern, necessitating the development of either new antibiotics or advanced delivery methods. With this in mind, we report on the synthesis and characterisation of a new family of Metal-Organic Frameworks (MOFs), OnG6 MOFs, designed to act as multi-drug carriers for bacterial infection treatment. OnG6 is based on the pro-drug 4,4'-azodisalicylic acid (AZDH4), which in vivo produces two equivalents of para-aminosalicylic acid (ASA), a crucial drug for M. tuberculosis treatment. X-ray and computational studies revealed that OnG6 MOFs are mesoporous MOFs with etb topology and an [M2(AZD)] formula (M = Zn, OnG6-Zn; Mg, OnG6-Mg; Cu, OnG6-Cu; and Co, OnG6-Co), featuring 1-dimensional channel type pores of 25 Å diameter. OnG6 MOFs are the first reported MOFs bearing the ligand AZDH4, joining the family of mesoporous MOFs arranged in a honeycomb pattern. They absorb isoniazid (INH) and ciprofloxacin (CIPRO) with the former being a specific antibiotic for M. tuberculosis, and the latter being a broader-spectrum antibiotic. The stability of the MOFs and their capacity for antibiotic uptake depend on the nature of the metal ion, with OnG6-Mg demonstrating the highest drug absorption. The antimicrobial activity of these species was assessed against S. aureus and E. coli, revealing that the carriers containing CIPRO displayed optimal efficacy.
Collapse
Affiliation(s)
- Ahmed Ahmed
- SSPC The Science Foundation Ireland Research Centre for, Pharmaceuticals, Ireland
- School of Biological and Chemical Sciences, College of Science and Engineering, University of Galway, H91 TK 33 Galway, Ireland.
| | - Aileen Kelly
- School of Biological and Chemical Sciences, College of Science and Engineering, University of Galway, H91 TK 33 Galway, Ireland.
| | - Dayle Leonard
- School of Natural Sciences, College of Science and Engineering, University of Galway, H91 TK 33 Galway, Ireland
| | - Waleed Saleem
- School of Biological and Chemical Sciences, College of Science and Engineering, University of Galway, H91 TK 33 Galway, Ireland.
| | - Andrey Bezrukov
- Department of Chemical Sciences, Bernal Institute, University of Limerick, Limerick, V94T9PX, Republic of Ireland
| | | | - Michael J Zaworotko
- SSPC The Science Foundation Ireland Research Centre for, Pharmaceuticals, Ireland
- Department of Chemical Sciences, Bernal Institute, University of Limerick, Limerick, V94T9PX, Republic of Ireland
| | - Davide Tiana
- SSPC The Science Foundation Ireland Research Centre for, Pharmaceuticals, Ireland
- School of Chemistry, University College Cork, College Road, Cork, Ireland
| | - Aoife Boyd
- School of Natural Sciences, College of Science and Engineering, University of Galway, H91 TK 33 Galway, Ireland
| | - Constantina Papatriantafyllopoulou
- SSPC The Science Foundation Ireland Research Centre for, Pharmaceuticals, Ireland
- School of Biological and Chemical Sciences, College of Science and Engineering, University of Galway, H91 TK 33 Galway, Ireland.
| |
Collapse
|
2
|
Liu L, Zhuang H, Wang Y, Tu Y, Yu Y, Chen Y, Wu X. β-Hemolysin, not agrA mutation, inhibits the hemolysis of α-hemolysin in Staphylococcus aureus laboratory and clinical strains. mSphere 2024; 9:e0067323. [PMID: 38289073 PMCID: PMC10900901 DOI: 10.1128/msphere.00673-23] [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: 11/01/2023] [Accepted: 12/20/2023] [Indexed: 02/29/2024] Open
Abstract
Staphylococcus aureus produces various hemolysins regulated by the Agr-QS system, except β-hemolysin encoded by the gene hlb. A classical laboratory S. aureus strain RN4220 displays only the β-hemolysin phenotype. It was suspected that the 8A mutation at the end of its agrA gene delayed the expressions of hla and RNAIII, then failed to express α- and δ-hemolysins. However, hla gene expression was detected at the later culture time without α-hemolysin phenotype, the reason for such a phenotype has not been clearly understood. We created hlb knockout and complementary mutants via homologous recombination in RN4220 and NRS049, two strains that normally produce β-hemolysin and carry agrA mutation. We found interestingly that the presence or absence of α-hemolysin phenotype in such strains depended on the expression of β-hemolysin instead of agrA mutations, which only inhibited δ-hemolysin expression. The hemolysis phenotype was verified by the Christie-Atkinson-Munch-Peterson (CAMP) test. Quantitative reverse transcription PCR was carried out to evaluate the relative gene expressions of hlb, hla, and RNAIII. The construction of mutants did not affect the agrA mutation status. We demonstrate that the absence of α-hemolysin in S. aureus RN4220 and NRS049 strains is attributed to their production of β-hemolysin instead of agrA mutation. Our findings broaden the understanding of the molecular mechanisms that control hemolysin expression in S. aureus that is crucial for the development of new therapeutic strategies to combat S. aureus infections. IMPORTANCE α-Hemolysin is a critical virulence factor in Staphylococcus aureus and its expression is largely controlled by the Agr-QS system. Nonetheless, the hemolysis phenotype and the regulation of the Agr-QS system in S. aureus still hold many mysteries. Our study finds that it is the expression of β- hemolysin rather than the agrA mutation that inhibits the function of the α-hemolysin in an important S. aureus strain RN4220 and a clinical strain presents a similar phenotype, which clarifies the misunderstood hemolytic phenotype and mechanism of S. aureus. Our findings highlight the interactions among different toxins and their biological roles, combined with QS system regulation, which is ultimately the true underlying cause of its virulence. This emphasizes the importance of considering the collaborative action of various factors in the infection process caused by this significant human pathogen.
Collapse
Affiliation(s)
- Lin Liu
- Department of Infectious Disease, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Laboratory Medicine Center, Department of Clinical Laboratory, Zhejiang Provincial People’s Hospital, Affiliated People’s Hospital, Hangzhou Medical College, Hangzhou, Zhejiang, China
| | - Hemu Zhuang
- Department of Infectious Disease, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, Zhejiang, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Department of Respiratory and Critical Medicine, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Yanfei Wang
- Department of Infectious Disease, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, Zhejiang, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Yuexing Tu
- Laboratory Medicine Center, Department of Clinical Laboratory, Zhejiang Provincial People’s Hospital, Affiliated People’s Hospital, Hangzhou Medical College, Hangzhou, Zhejiang, China
- Department of Critical Care Medicine, Tongde Hospital of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Yunsong Yu
- Department of Infectious Disease, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, Zhejiang, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Yan Chen
- Department of Infectious Disease, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, Zhejiang, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Xueqing Wu
- Department of Infectious Disease, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, Zhejiang, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| |
Collapse
|
3
|
Truong-Bolduc QC, Yonker LM, Wang Y, Lawton BG, Hooper DC. NorA efflux pump mediates Staphylococcus aureus response to Pseudomonas aeruginosa pyocyanin toxicity. Antimicrob Agents Chemother 2024; 68:e0100123. [PMID: 38231535 PMCID: PMC10848749 DOI: 10.1128/aac.01001-23] [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: 07/31/2023] [Accepted: 12/03/2023] [Indexed: 01/18/2024] Open
Abstract
Endogenous transporters protect Staphylococcus aureus against antibiotics and also contribute to bacterial defense from environmental toxins. We evaluated the effect of overexpression of four efflux pumps, NorA, NorB, NorC, and Tet38, on S. aureus survival following exposure to pyocyanin (PYO) of Pseudomonas aeruginosa, using a well diffusion assay. We measured the PYO-created inhibition zone and found that only an overexpression of NorA reduced S. aureus susceptibility to pyocyanin killing. The MICPYO of the NorA overexpressor increased threefold compared to that of wild-type RN6390 and was reduced 2.5-fold with reserpine, suggesting that increased NorA efflux caused PYO resistance. The PYO-created inhibition zone of a ΔnorA mutant was consistently larger than that of a plasmid-borne NorA overexpressor. PYO also produced a modest increase in norA expression (1.8-fold at 0.25 µg/mL PYO) that gradually decreased with increasing PYO concentrations. Well diffusion assays carried out using P. aeruginosa showed that ΔnorA mutant was less susceptible to killing by PYO-deficient mutants PA14phzM and PA14phzS than to killing by PA14. NorA overexpression led to reduced killing by all tested P. aeruginosa. We evaluated the NorA-PYO interaction using a collection of 22 clinical isolates from adult and pediatric cystic fibrosis (CF) patients, which included both S. aureus (CF-SA) and P. aeruginosa (CF-PA). We found that when isolated alone, CF-PA and CF-SA expressed varying levels of PYO and norA transcripts, but all four CF-PA/CF-SA pairs isolated concurrently from CF patients produced a low level of PYO and low norA transcript levels, respectively, suggesting a partial adaptation of the two bacteria in circumstances of persistent co-colonization.
Collapse
Affiliation(s)
- Q. C. Truong-Bolduc
- Infectious Diseases Division and Medical Services, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - L. M. Yonker
- Department of Pediatrics, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Y. Wang
- Infectious Diseases Division and Medical Services, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - B. G. Lawton
- Department of Pediatrics, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - D. C. Hooper
- Infectious Diseases Division and Medical Services, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| |
Collapse
|
4
|
Reed P, Sorg M, Alwardt D, Serra L, Veiga H, Schäper S, Pinho MG. A CRISPRi-based genetic resource to study essential Staphylococcus aureus genes. mBio 2024; 15:e0277323. [PMID: 38054745 PMCID: PMC10870820 DOI: 10.1128/mbio.02773-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 10/19/2023] [Indexed: 12/07/2023] Open
Abstract
IMPORTANCE Staphylococcus aureus is an important clinical pathogen that causes a high number of antibiotic-resistant infections. The study of S. aureus biology, and particularly of the function of essential proteins, is of particular importance to develop new approaches to combat this pathogen. We have optimized a clustered regularly interspaced short palindromic repeat interference (CRISPRi) system that allows efficient targeting of essential S. aureus genes. Furthermore, we have used that system to construct a library comprising 261 strains, which allows the depletion of essential proteins encoded by 200 genes/operons. This library, which we have named Lisbon CRISPRi Mutant Library, should facilitate the study of S. aureus pathogenesis and biology.
Collapse
Affiliation(s)
- Patricia Reed
- Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Moritz Sorg
- Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Dominik Alwardt
- Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Lúcia Serra
- Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Helena Veiga
- Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Simon Schäper
- Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Mariana G. Pinho
- Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| |
Collapse
|
5
|
Jenull S, Bauer T, Silbermayr K, Dreer M, Stark TD, Ehling-Schulz M. The toxicological spectrum of the Bacillus cereus toxin cereulide points towards niche-specific specialisation. Environ Microbiol 2023; 25:2231-2249. [PMID: 37354053 DOI: 10.1111/1462-2920.16454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 06/06/2023] [Indexed: 06/26/2023]
Abstract
Most microbes share their environmental niches with very different forms of life thereby engaging in specialised relationships to enable their persistence. The bacterium Bacillus cereus occurs ubiquitously in the environment with certain strain backgrounds causing foodborne and opportunistic infections in humans. The emetic lineage of B. cereus is capable of producing the toxin cereulide, which evokes emetic illnesses. Although food products favouring the accumulation of cereulide are known, the ecological role of cereulide and the environmental niche of emetic B. cereus remain elusive. To better understand the ecology of cereulide-producing B. cereus, we systematically assayed the toxicological spectrum of cereulide on a variety of organisms belonging to different kingdoms. As cereulide is a potassium ionophore, we further tested the effect of environmental potassium levels on the action of cereulide. We found that adverse effects of cereulide exposure are species-specific, which can be exacerbated with increased environmental potassium. Additionally, we demonstrate that cereulide is produced within an insect cadaver indicating its potential ecological function for a saprophytic lifestyle. Collectively, distinct cereulide susceptibilities of other organisms may reflect its role in enabling competitive niche specialization of emetic B. cereus.
Collapse
Affiliation(s)
- Sabrina Jenull
- Institute of Microbiology, Department of Pathobiology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Tobias Bauer
- Institute of Microbiology, Department of Pathobiology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Katja Silbermayr
- Institute of Parasitology, Department of Pathobiology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Maximilian Dreer
- Department of Functional and Evolutionary Ecology, Archaea Biology and Ecogenomics Unit, University of Vienna, Vienna, Austria
| | - Timo D Stark
- Food Chemistry and Molecular Sensory Science, Technical University of Munich, Freising, Germany
| | - Monika Ehling-Schulz
- Institute of Microbiology, Department of Pathobiology, University of Veterinary Medicine Vienna, Vienna, Austria
| |
Collapse
|
6
|
Andrade-Oliveira AL, Lacerda-Rodrigues G, Pereira MF, Bahia AC, Machado EDA, Rossi CC, Giambiagi-deMarval M. Tenebrio molitor as a model system to study Staphylococcus spp virulence and horizontal gene transfer. Microb Pathog 2023; 183:106304. [PMID: 37567328 DOI: 10.1016/j.micpath.2023.106304] [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: 05/12/2023] [Revised: 07/23/2023] [Accepted: 08/09/2023] [Indexed: 08/13/2023]
Abstract
Invertebrates can provide a valuable alternative to traditional vertebrate animal models for studying bacterial and fungal infections. This study aimed to establish the larvae of the coleoptera Tenebrio molitor (mealworm) as an in vivo model for evaluating virulence and horizontal gene transfer between Staphylococcus spp. After identifying the best conditions for rearing T. molitor, larvae were infected with different Staphylococcus species, resulting in dose-dependent killing curves. All species tested killed the insects at higher doses, with S. nepalensis and S. aureus being the most and least virulent, respectively. However, only S. nepalensis was able to kill more than 50% of larvae 72 h post-infection at a low amount of 105 CFU. Staphylococcus infection also stimulated an increase in the concentration of hemocytes present in the hemolymph, which was proportional to the virulence. To investigate T. molitor's suitability as an in vivo model for plasmid transfer studies, we used S. aureus strains as donor and recipient of a plasmid containing the gentamicin resistance gene aac(6')-aph(2″). By inoculating larvae with non-lethal doses of each, we observed conjugation, and obtained transconjugant colonies with a frequency of 1.6 × 10-5 per donor cell. This study demonstrates the potential of T. molitor larvae as a reliable and cost-effective model for analyzing the virulence of Staphylococcus and, for the first time, an optimal environment for the plasmid transfer between S. aureus carrying antimicrobial resistance genes.
Collapse
Affiliation(s)
- Ana Luisa Andrade-Oliveira
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Geovana Lacerda-Rodrigues
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Monalessa Fábia Pereira
- Departamento de Ciências Biológicas, Universidade do Estado de Minas Gerais, Carangola, MG, Brazil
| | - Ana Cristina Bahia
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciencia e Tecnologia em Entomologia Molecular, Rio de Janeiro, Brazil
| | - Ednildo de Alcântara Machado
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciencia e Tecnologia em Entomologia Molecular, Rio de Janeiro, Brazil
| | - Ciro César Rossi
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal de Viçosa, Viçosa, MG, Brazil
| | - Marcia Giambiagi-deMarval
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
| |
Collapse
|
7
|
Das S, Ahmad Z, Singh S, Singh S, Wright RE, Giri S, Kumar A. Oral administration of S-nitroso-L-glutathione (GSNO) provides anti-inflammatory and cytoprotective effects during ocular bacterial infections. Cell Mol Life Sci 2023; 80:309. [PMID: 37770649 PMCID: PMC11072052 DOI: 10.1007/s00018-023-04963-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 08/20/2023] [Accepted: 09/12/2023] [Indexed: 09/30/2023]
Abstract
Bacterial endophthalmitis is a severe complication of eye surgeries that can lead to vision loss. Current treatment involves intravitreal antibiotic injections that control bacterial growth but not inflammation. To identify newer therapeutic targets to promote inflammation resolution in endophthalmitis, we recently employed an untargeted metabolomics approach. This led to the discovery that the levels of S-nitroso-L-glutathione (GSNO) were significantly reduced in an experimental murine Staphylococcus aureus (SA) endophthalmitis model. In this study, we tested the hypothesis whether GSNO supplementation via different routes (oral, intravitreal) provides protection during bacterial endophthalmitis. Our results show that prophylactic administration of GSNO via intravitreal injections ameliorated SA endophthalmitis. Therapeutically, oral administration of GSNO was found to be most effective in reducing intraocular inflammation and bacterial burden. Moreover, oral GSNO treatment synergized with intravitreal antibiotic injections in reducing the severity of endophthalmitis. Furthermore, in vitro experiments using cultured human retinal Muller glia and retinal pigment epithelial (RPE) cells showed that GSNO treatment reduced SA-induced inflammatory mediators and cell death. Notably, both in-vivo and ex-vivo data showed that GSNO strengthened the outer blood-retinal barrier during endophthalmitis. Collectively, our study demonstrates GSNO as a potential therapeutic agent for the treatment of intraocular infections due to its dual anti-inflammatory and cytoprotective properties.
Collapse
Affiliation(s)
- Susmita Das
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, 4717 St. Antoine, Detroit, MI, 48201, USA
| | - Zeeshan Ahmad
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, 4717 St. Antoine, Detroit, MI, 48201, USA
| | - Sneha Singh
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, 4717 St. Antoine, Detroit, MI, 48201, USA
| | - Sukhvinder Singh
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, 4717 St. Antoine, Detroit, MI, 48201, USA
| | - Robert Emery Wright
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, 4717 St. Antoine, Detroit, MI, 48201, USA
| | - Shailendra Giri
- Department of Neurology, Henry Ford Health System, Detroit, MI, USA
| | - Ashok Kumar
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, 4717 St. Antoine, Detroit, MI, 48201, USA.
- Department of Biochemistry, Microbiology, and Immunology, Wayne State University School of Medicine, Detroit, MI, USA.
| |
Collapse
|
8
|
Vaca DJ, Frenzel F, Ballhorn W, Torres SG, Leisegang MS, Günther S, Bender D, Kraiczy P, Göttig S, Kempf VAJ. Adhesion of human pathogenic bacteria to endothelial cells is facilitated by fibronectin interaction. Microbes Infect 2023; 25:105172. [PMID: 37343664 DOI: 10.1016/j.micinf.2023.105172] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 06/07/2023] [Accepted: 06/10/2023] [Indexed: 06/23/2023]
Abstract
Human pathogenic bacteria circulating in the bloodstream need to find a way to interact with endothelial cells (ECs) lining the blood vessels to infect and colonise the host. The extracellular matrix (ECM) of ECs might represent an attractive initial target for bacterial interaction, as many bacterial adhesins have reported affinities to ECM proteins, in particular to fibronectin (Fn). Here, we analysed the general role of EC-expressed Fn for bacterial adhesion. For this, we evaluated the expression levels of ECM coding genes in different ECs, revealing that Fn is the highest expressed gene and thereby, it is highly abundant in the ECM environment of ECs. The role of Fn as a mediator in bacterial cell-host adhesion was evaluated in adhesion assays of Acinetobacter baumannii, Bartonella henselae, Borrelia burgdorferi, and Staphylococcus aureus to ECs. The assays demonstrated that bacteria colocalised with Fn fibres, as observed by confocal laser scanning microscopy. Fn removal from the ECM environment (FN1 knockout ECs) diminished bacterial adherence to ECs in both static and dynamic adhesion assays to varying extents, as evaluated via absolute quantification using qPCR. Interactions between adhesins and Fn might represent the crucial step for the adhesion of human-pathogenic Gram-negative and Gram-positive bacteria targeting the ECs as a niche of infection.
Collapse
Affiliation(s)
- Diana J Vaca
- Institute of Medical Microbiology and Infection Control, Goethe University, Paul Ehrlich Straße 40, 60596, Frankfurt, Germany.
| | - Fabienne Frenzel
- Institute of Medical Microbiology and Infection Control, Goethe University, Paul Ehrlich Straße 40, 60596, Frankfurt, Germany.
| | - Wibke Ballhorn
- Institute of Medical Microbiology and Infection Control, Goethe University, Paul Ehrlich Straße 40, 60596, Frankfurt, Germany.
| | - Sara Garcia Torres
- Institute of Medical Microbiology and Infection Control, Goethe University, Paul Ehrlich Straße 40, 60596, Frankfurt, Germany.
| | - Matthias S Leisegang
- Institute for Cardiovascular Physiology, Goethe University, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany; German Center of Cardiovascular Research (DZHK), Partner Site RheinMain, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany.
| | - Stefan Günther
- Max Planck Institute for Heart and Lung Research, Parkstraße 1, 61231, Bad Nauheim, Germany.
| | - Daniela Bender
- Federal Institute for Vaccines and Biomedicines, Department of Virology, Paul Ehrlich Institute, Paul-Ehrlich-Straße 51-59, 63225, Langen, Germany.
| | - Peter Kraiczy
- Institute of Medical Microbiology and Infection Control, Goethe University, Paul Ehrlich Straße 40, 60596, Frankfurt, Germany.
| | - Stephan Göttig
- Institute of Medical Microbiology and Infection Control, Goethe University, Paul Ehrlich Straße 40, 60596, Frankfurt, Germany.
| | - Volkhard A J Kempf
- Institute of Medical Microbiology and Infection Control, Goethe University, Paul Ehrlich Straße 40, 60596, Frankfurt, Germany.
| |
Collapse
|
9
|
Khan NA, Amorim FG, Dunbar JP, Leonard D, Redureau D, Quinton L, Dugon MM, Boyd A. Inhibition of bacterial biofilms by the snake venom proteome. BIOTECHNOLOGY REPORTS (AMSTERDAM, NETHERLANDS) 2023; 39:e00810. [PMID: 37559690 PMCID: PMC10407894 DOI: 10.1016/j.btre.2023.e00810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 08/11/2023]
Abstract
Snake venoms possess a range of pharmacological and toxicological activities. Here we evaluated the antibacterial and anti-biofilm activity against methicillin-susceptible and methicillin-resistant Staphylococcus aureus (MSSA and MRSA) of venoms from the Samar spitting cobra Naja samarensis and the Puff adder Bitis arietans. Both venoms prevented biofilm production by pathogenic S. aureus in a growth-independent manner, with the B. arietans venom being most potent. Fractionation showed the active molecule to be heat-labile and >10 kDa in size. Proteomic profiles of N. samarensis venom revealed neurotoxins and cytotoxins, as well as an abundance of serine proteases and three-finger toxins, while serine proteases, metalloproteinases and C-lectin types were abundant in B. arietans venom. These enzymes may have evolved to prevent bacteria colonising the snake venom gland. From a biomedical biotechnology perspective, they have valuable potential for anti-virulence therapy to fight antibiotic resistant microbes.
Collapse
Affiliation(s)
- Neyaz A. Khan
- Pathogenic Mechanisms Research Group, School of Natural Sciences, University of Galway, Ireland
| | | | - John P. Dunbar
- Venom Systems & Proteomics Lab, School of Natural Sciences, Ryan Institute, University of Galway, Ireland
| | - Dayle Leonard
- Pathogenic Mechanisms Research Group, School of Natural Sciences, University of Galway, Ireland
- Venom Systems & Proteomics Lab, School of Natural Sciences, Ryan Institute, University of Galway, Ireland
| | - Damien Redureau
- Mass Spectrometry Laboratory, MolSys RU, University of Liège, Belgium
| | - Loïc Quinton
- Mass Spectrometry Laboratory, MolSys RU, University of Liège, Belgium
| | - Michel M. Dugon
- Venom Systems & Proteomics Lab, School of Natural Sciences, Ryan Institute, University of Galway, Ireland
| | - Aoife Boyd
- Pathogenic Mechanisms Research Group, School of Natural Sciences, University of Galway, Ireland
| |
Collapse
|
10
|
Walzl A, Marbach H, Belikova D, Vogl C, Ehling-Schulz M, Heilbronner S, Grunert T. Prevalence of the SigB-Deficient Phenotype among Clinical Staphylococcus aureus Isolates Linked to Bovine Mastitis. Antibiotics (Basel) 2023; 12:699. [PMID: 37107061 PMCID: PMC10135042 DOI: 10.3390/antibiotics12040699] [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: 03/01/2023] [Revised: 03/27/2023] [Accepted: 03/30/2023] [Indexed: 04/07/2023] Open
Abstract
Phenotypic adaptation has been associated with persistent, therapy-resistant Staphylococcus aureus infections. Recently, we described within-host evolution towards a Sigma factor B (SigB)-deficient phenotype in a non-human host, a naturally infected dairy cow with chronic, persistent mastitis. However, to our knowledge, the prevalence of SigB deficiency among clinical S. aureus isolates remains unknown. In this study, we screened a collection of bovine mastitis isolates for phenotypic traits typical for SigB deficiency: decreased carotenoid pigmentation, increased proteolysis, secretion of α-hemolysin and exoproteins. Overall, 8 out of 77 (10.4%) isolates of our bovine mastitis collection exhibited the SigB-deficient phenotype. These isolates were assigned to various clonal complexes (CC8, CC9, CC97, CC151, CC3666). We further demonstrated a strong positive correlation between asp23-expression (a marker of SigB activity) and carotenoid pigmentation (r = 0.6359, p = 0.0008), underlining the role of pigmentation as a valuable predictor of the functional status of SigB. Sequencing of the sigB operon (mazEF-rsbUVW-sigB) indicated the phosphatase domain of the RsbU protein as a primary target of mutations leading to SigB deficiency. Indeed, by exchanging single nucleotides in rsbU, we could either induce SigB deficiency or restore the SigB phenotype, demonstrating the pivotal role of RsbU for SigB functionality. The data presented highlight the clinical relevance of SigB deficiency, and future studies are needed to exploit its role in staphylococcal infections.
Collapse
Affiliation(s)
- Anna Walzl
- Institute of Microbiology, Department of Pathobiology, University of Veterinary Medicine, A-1210 Vienna, Austria
| | - Helene Marbach
- Institute of Microbiology, Department of Pathobiology, University of Veterinary Medicine, A-1210 Vienna, Austria
| | - Darya Belikova
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, D-72076 Tübingen, Germany
| | - Claus Vogl
- Molecular Genetics, Institute of Animal Breeding and Genetics, Department of Biomedical Sciences, University of Veterinary Medicine, A-1210 Vienna, Austria
| | - Monika Ehling-Schulz
- Institute of Microbiology, Department of Pathobiology, University of Veterinary Medicine, A-1210 Vienna, Austria
| | - Simon Heilbronner
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, D-72076 Tübingen, Germany
| | - Tom Grunert
- Institute of Microbiology, Department of Pathobiology, University of Veterinary Medicine, A-1210 Vienna, Austria
| |
Collapse
|
11
|
Alsultan A, Walton G, Andrews SC, Clarke SR. Staphylococcus aureus FadB is a dehydrogenase that mediates cholate resistance and survival under human colonic conditions. MICROBIOLOGY (READING, ENGLAND) 2023; 169. [PMID: 36947574 DOI: 10.1099/mic.0.001314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/23/2023]
Abstract
Staphylococcus aureus is a common colonizer of the human gut and in doing so it must be able to resist the actions of the host's innate defences. Bile salts are a class of molecules that possess potent antibacterial activity that control growth. Bacteria that colonize and survive in that niche must be able to resist the action of bile salts, but the mechanisms by which S. aureus does so are poorly understood. Here we show that FadB is a bile-induced oxidoreductase which mediates bile salt resistance and when heterologously expressed in Escherichia coli renders them resistant. Deletion of fadB attenuated survival of S. aureus in a model of the human distal colon.
Collapse
Affiliation(s)
- Amjed Alsultan
- School of Biological Sciences, University of Reading, Whiteknights, Reading, RG6 6EX, UK
- Present address: Department of Internal and Preventive Medicine, College of Veterinary Medicine, University of Al-qadisiyah, Aldewanyiah, Iraq
| | - Gemma Walton
- Food Microbial Sciences Unit, Department of Food and Nutritional Sciences, University of Reading, Whiteknights, Reading, RG6 6AP, UK
| | - Simon C Andrews
- School of Biological Sciences, University of Reading, Whiteknights, Reading, RG6 6EX, UK
| | - Simon R Clarke
- School of Biological Sciences, University of Reading, Whiteknights, Reading, RG6 6EX, UK
| |
Collapse
|
12
|
Staphylococcus aureus Prophage-Encoded Protein Causes Abortive Infection and Provides Population Immunity against Kayviruses. mBio 2023; 14:e0249022. [PMID: 36779718 PMCID: PMC10127798 DOI: 10.1128/mbio.02490-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
Both temperate and obligately lytic phages have crucial roles in the biology of staphylococci. While superinfection exclusion among closely related temperate phages is a well-characterized phenomenon, the interactions between temperate and lytic phages in staphylococci are not understood. Here, we present a resistance mechanism toward lytic phages of the genus Kayvirus, mediated by the membrane-anchored protein designated PdpSau encoded by Staphylococcus aureus prophages, mostly of the Sa2 integrase type. The prophage accessory gene pdpSau is strongly linked to the lytic genes for holin and ami2-type amidase and typically replaces genes for the toxin Panton-Valentine leukocidin (PVL). The predicted PdpSau protein structure shows the presence of a membrane-binding α-helix in its N-terminal part and a cytoplasmic positively charged C terminus. We demonstrated that the mechanism of action of PdpSau does not prevent the infecting kayvirus from adsorbing onto the host cell and delivering its genome into the cell, but phage DNA replication is halted. Changes in the cell membrane polarity and permeability were observed from 10 min after the infection, which led to prophage-activated cell death. Furthermore, we describe a mechanism of overcoming this resistance in a host-range Kayvirus mutant, which was selected on an S. aureus strain harboring prophage 53 encoding PdpSau, and in which a chimeric gene product emerged via adaptive laboratory evolution. This first case of staphylococcal interfamily phage-phage competition is analogous to some other abortive infection defense systems and to systems based on membrane-destructive proteins. IMPORTANCE Prophages play an important role in virulence, pathogenesis, and host preference, as well as in horizontal gene transfer in staphylococci. In contrast, broad-host-range lytic staphylococcal kayviruses lyse most S. aureus strains, and scientists worldwide have come to believe that the use of such phages will be successful for treating and preventing bacterial diseases. The effectiveness of phage therapy is complicated by bacterial resistance, whose mechanisms related to therapeutic staphylococcal phages are not understood in detail. In this work, we describe a resistance mechanism targeting kayviruses that is encoded by a prophage. We conclude that the defense mechanism belongs to a broader group of abortive infections, which is characterized by suicidal behavior of infected cells that are unable to produce phage progeny, thus ensuring the survival of the host population. Since the majority of staphylococcal strains are lysogenic, our findings are relevant for the advancement of phage therapy.
Collapse
|
13
|
Kutsuno S, Hayashi I, Yu L, Yamada S, Hisatsune J, Sugai M. Non-deacetylated poly- N-acetylglucosamine-hyperproducing Staphylococcus aureus undergoes immediate autoaggregation upon vortexing. Front Microbiol 2023; 13:1101545. [PMID: 36699608 PMCID: PMC9868172 DOI: 10.3389/fmicb.2022.1101545] [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: 11/18/2022] [Accepted: 12/14/2022] [Indexed: 01/11/2023] Open
Abstract
Biofilms are microbial communities of cells embedded in a matrix of extracellular polymeric substances generated and adhering to each other or to a surface. Cell aggregates formed in the absence of a surface and floating pellicles that form biofilms at the air-liquid interface are also considered to be a type of biofilm. Staphylococcus aureus is a well-known cause of biofilm infections and high-molecular-weight polysaccharides, poly-N-acetylglucosamine (PNAG) is a main constituent of the biofilm. An icaADBC operon comprises major machinery to synthesize and extracellularly secrete PNAG. Extracellular PNAG is partially deacetylated by IcaB deacetylase, and the positively charged PNAG hence interacts with negatively charged cell surface to form the major component of biofilm. We previously reported a new regulator of biofilm (Rob) and demonstrated that Rob binds to a unique 5-bp motif, TATTT, present in intergenic region between icaADBC operon and its repressor gene icaR in Yu et al. The deletion of the 5-bp motif induces excessive adherent biofilm formation. The real function of the 5-bp motif is still unknown. In an attempt to isolate the 5-bp motif deletion mutant, we isolated several non-adherent mutants. They grew normally in turbid broth shaking culture but immediately auto-aggregated upon weak vortexing and sedimented as a lump resulting in a clear supernatant. Whole genome sequencing of the mutants identified they all carried mutations in icaB in addition to deletion of the 5-bp motif. Purification and molecular characterization of auto-aggregating factor in the culture supernatant of the mutant identified that the factor was a massively produced non-deacetylated PNAG. Therefore, we created a double deficient strain of biofilm inhibitory factors (5-bp motif, icaR, rob) and icaB to confirm the aggregation phenomenon. This peculiar phenomenon was only observed in Δ5bpΔicaB double mutant but not in ΔicaR ΔicaB or ΔrobΔicaB mutant. This study explains large amount of extracellularly produced non-deacetylated PNAG by Δ5bpΔicaB double mutation induced rapid auto-aggregation of S. aureus cells by vortexing. This phenomenon indicated that Staphylococcus aureus may form biofilms that do not adhere to solid surfaces and we propose this as a new mechanism of non-adherent biofilm formation of S. aureus.
Collapse
Affiliation(s)
- Shoko Kutsuno
- Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Tokyo, Japan,Department of Antimicrobial Resistance, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima, Japan
| | - Ikue Hayashi
- Research Facility, Hiroshima University Faculty of Dentistry, Hiroshima, Japan
| | - Liansheng Yu
- Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Tokyo, Japan,Department of Antimicrobial Resistance, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima, Japan
| | - Sakuo Yamada
- Department of Medical Technology, Faculty of Health Sciences & Technology, Kawasaki University of Medical Welfare, Okayama, Japan
| | - Junzo Hisatsune
- Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Tokyo, Japan,Department of Antimicrobial Resistance, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima, Japan
| | - Motoyuki Sugai
- Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Tokyo, Japan,Department of Antimicrobial Resistance, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima, Japan,*Correspondence: Motoyuki Sugai,
| |
Collapse
|
14
|
Rodrigues Lopes I, Alcantara LM, Silva RJ, Josse J, Vega EP, Cabrerizo AM, Bonhomme M, Lopez D, Laurent F, Vandenesch F, Mano M, Eulalio A. Microscopy-based phenotypic profiling of infection by Staphylococcus aureus clinical isolates reveals intracellular lifestyle as a prevalent feature. Nat Commun 2022; 13:7174. [PMID: 36418309 PMCID: PMC9684519 DOI: 10.1038/s41467-022-34790-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 11/08/2022] [Indexed: 11/24/2022] Open
Abstract
Staphylococcus aureus is increasingly recognized as a facultative intracellular pathogen, although the significance and pervasiveness of its intracellular lifestyle remain controversial. Here, we applied fluorescence microscopy-based infection assays and automated image analysis to profile the interaction of 191 S. aureus isolates from patients with bone/joint infections, bacteremia, and infective endocarditis, with four host cell types, at five times post-infection. This multiparametric analysis revealed that almost all isolates are internalized and that a large fraction replicate and persist within host cells, presenting distinct infection profiles in non-professional vs. professional phagocytes. Phenotypic clustering highlighted interesting sub-groups, including one comprising isolates exhibiting high intracellular replication and inducing delayed host death in vitro and in vivo. These isolates are deficient for the cysteine protease staphopain A. This study establishes S. aureus intracellular lifestyle as a prevalent feature of infection, with potential implications for the effective treatment of staphylococcal infections.
Collapse
Affiliation(s)
- Ines Rodrigues Lopes
- grid.8051.c0000 0000 9511 4342RNA & Infection Laboratory, Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal ,grid.8051.c0000 0000 9511 4342Functional Genomics and RNA-based Therapeutics Laboratory, Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal
| | - Laura Maria Alcantara
- grid.8051.c0000 0000 9511 4342RNA & Infection Laboratory, Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal
| | - Ricardo Jorge Silva
- grid.8051.c0000 0000 9511 4342Functional Genomics and RNA-based Therapeutics Laboratory, Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal
| | - Jerome Josse
- grid.15140.310000 0001 2175 9188Centre International de Recherche en Infectiologie (CIRI), Université de Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, Lyon, France
| | - Elena Pedrero Vega
- grid.4711.30000 0001 2183 4846National Centre for Biotechnology, Spanish National Research Council (CNB-CSIC), Madrid, Spain
| | - Ana Marina Cabrerizo
- grid.4711.30000 0001 2183 4846National Centre for Biotechnology, Spanish National Research Council (CNB-CSIC), Madrid, Spain
| | - Melanie Bonhomme
- grid.15140.310000 0001 2175 9188Centre International de Recherche en Infectiologie (CIRI), Université de Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, Lyon, France
| | - Daniel Lopez
- grid.4711.30000 0001 2183 4846National Centre for Biotechnology, Spanish National Research Council (CNB-CSIC), Madrid, Spain
| | - Frederic Laurent
- grid.15140.310000 0001 2175 9188Centre International de Recherche en Infectiologie (CIRI), Université de Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, Lyon, France ,grid.413852.90000 0001 2163 3825Centre National de Référence des Staphylocoques, Institut des Agents Infectieux, Hospices Civils de Lyon, Lyon, France
| | - Francois Vandenesch
- grid.15140.310000 0001 2175 9188Centre International de Recherche en Infectiologie (CIRI), Université de Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, Lyon, France ,grid.413852.90000 0001 2163 3825Centre National de Référence des Staphylocoques, Institut des Agents Infectieux, Hospices Civils de Lyon, Lyon, France
| | - Miguel Mano
- grid.8051.c0000 0000 9511 4342Functional Genomics and RNA-based Therapeutics Laboratory, Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal ,grid.8051.c0000 0000 9511 4342Department of Life Sciences, University of Coimbra, Coimbra, Portugal ,grid.13097.3c0000 0001 2322 6764British Heart Foundation Centre of Research Excellence, School of Cardiovascular and Metabolic Medicine & Sciences, King’s College London, London, United Kingdom
| | - Ana Eulalio
- grid.8051.c0000 0000 9511 4342RNA & Infection Laboratory, Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal ,grid.7311.40000000123236065Institute of Biomedicine (iBiMED), Department of Medical Sciences, University of Aveiro, Aveiro, Portugal ,grid.7445.20000 0001 2113 8111Department of Life Sciences, Imperial College London, London, United Kingdom
| |
Collapse
|
15
|
Panthee S, Hamamoto H, Paudel A, Kaito C, Suzuki Y, Sekimizu K. Hybrid assembly using long reads resolves repeats and completes the genome sequence of a laboratory strain of Staphylococcus aureus subsp. Aureus RN4220. Heliyon 2022; 8:e11376. [PMID: 36387480 PMCID: PMC9660545 DOI: 10.1016/j.heliyon.2022.e11376] [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: 01/16/2022] [Revised: 06/30/2022] [Accepted: 10/27/2022] [Indexed: 11/07/2022] Open
Abstract
Staphylococcus aureus RN4220 has been extensively used by staphylococcal researchers as an intermediate strain for genetic manipulation due to its ability to accept foreign DNA. Despite its wide use in laboratories, its complete genome is not available. In this study, we used a hybrid genome assembly approach using minION long reads and Illumina short reads to sequence the complete genome of S. aureus RN4220. The comparative analysis of the annotated complete genome showed the presence of 39 genes fragmented in the previous assembly, many of which were located near the repeat regions. Using RNA-Seq reads, we showed that a higher number of reads could be mapped to the complete genome than the draft genome and the gene expression profile obtained using the complete genome also differs from that obtained from the draft genome. Furthermore, by comparative transcriptomic analysis, we showed the correlation between expression levels of staphyloxanthin biosynthetic genes and the production of yellow pigment. This study highlighted the importance of long reads in completing microbial genomes, especially those possessing repetitive elements. S. aureus RN4220 is used as an intermediate strain for genetic manipulation. We completed its genome and found 39 fragmented genes in previous genome assembly. RNA-Seq analysis improved mapping of the reads with the use of complete genome. Expression of staphyloxanthin biosynthetic genes was correlated with its production.
Collapse
|
16
|
Activation of Human Platelets by Staphylococcus aureus Secreted Protease Staphopain A. Pathogens 2022; 11:pathogens11111237. [DOI: 10.3390/pathogens11111237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 10/19/2022] [Accepted: 10/24/2022] [Indexed: 11/17/2022] Open
Abstract
Infection by Staphylococcus aureus is the leading cause of infective endocarditis (IE). Activation of platelets by this pathogen results in their aggregation and thrombus formation which are considered to be important steps in the development and pathogenesis of IE. Here, we show that a secreted cysteine protease, staphopain A, activates human platelets and induces their aggregation. The culture supernatant of a scpA mutant deficient in staphopain A production was reduced in its ability to trigger platelet aggregation. The platelet agonist activity of purified staphopain A was inhibited by staphostatin A, a specific inhibitor, thus implicating its protease activity in the agonism. In whole blood, using concentrations of staphopain A that were otherwise insufficient to induce platelet aggregation, increased binding to collagen and thrombus formation was observed. Using antagonists specific to protease-activated receptors 1 and 4, we demonstrate their role in mediating staphopain A induced platelet activation.
Collapse
|
17
|
Solonamides, a Group of Cyclodepsipeptides, Influence Motility in the Native Producer Photobacterium galatheae S2753. Appl Environ Microbiol 2022; 88:e0110522. [PMID: 36000852 PMCID: PMC9469707 DOI: 10.1128/aem.01105-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The marine bacterium Photobacterium galatheae S2753 produces a group of cyclodepsipeptides, called solonamides, which impede the virulence but not the survival of Staphylococcus aureus. In addition to their invaluable antivirulence activity, little is known about the biosynthesis and physiological function of solonamides in the native producer. This study generated a solonamide-deficient (Δsol) mutant by in-frame deletion of the sol gene, thereby identifying the core gene for solonamide biosynthesis. By annotation from antiSMASH, the biosynthetic pathway of solonamides in S2753 was also proposed. Mass spectrometry analysis of cell extracts found that deficiency of solonamide production influenced the production of a group of unknown compounds but otherwise did not alter the overall secondary metabolite profile. Physiological comparison between Δsol and wild-type S2753 demonstrated that growth dynamics and biofilm formation of both strains were similar; however, the Δsol mutant displayed reduced motility rings compared to the wild type. Reintroduction of sol restored solonamide production and motility to the mutant, indicating that solonamides influence the motility behavior of P. galatheae S2753. Proteomic analysis of the Δsol and wild-type strains found that eliminating solonamides influenced many cellular processes, including swimming-related proteins and proteins adjusting the cellular cyclic di-GMP concentration. In conclusion, our results revealed the biosynthetic pathway of solonamides and their ecological benefits to P. galatheae S2753 by enhancing motility, likely by altering the motile physiology. IMPORTANCE The broad range of bioactive potentials of cyclodepsipeptides makes these compounds invaluable in the pharmaceutical industry. Recently, a few novel cyclodepsipeptides have been discovered in marine Proteobacteria; however, their biosynthetic pathways remain to be revealed. Here, we demonstrated the biosynthetic genetic basis and pathway of the antivirulence compounds known as solonamides in P. galatheae S2753. This can pave the way for the biological overproduction of solonamides on an industrial scale. Moreover, the comparison of a solonamide-deficient mutant and wild-type S2753 demonstrated that solonamides stimulate the swimming behavior of S2753 and also influence a few key physiological processes of the native producers. These results evidenced that, in addition to their importance as novel drug candidates, these compounds play a pivotal role in the physiology of the producing microorganisms and potentially provide the native producer competitive benefits for their survival in nature.
Collapse
|
18
|
Wong JJ, Ho FK, Choo PY, Chong KKL, Ho CMB, Neelakandan R, Keogh D, Barkham T, Chen J, Liu CF, Kline KA. Escherichia coli BarA-UvrY regulates the pks island and kills Staphylococci via the genotoxin colibactin during interspecies competition. PLoS Pathog 2022; 18:e1010766. [PMID: 36067266 PMCID: PMC9481169 DOI: 10.1371/journal.ppat.1010766] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 09/16/2022] [Accepted: 07/25/2022] [Indexed: 11/19/2022] Open
Abstract
Wound infections are often polymicrobial in nature, biofilm associated and therefore tolerant to antibiotic therapy, and associated with delayed healing. Escherichia coli and Staphylococcus aureus are among the most frequently cultured pathogens from wound infections. However, little is known about the frequency or consequence of E. coli and S. aureus polymicrobial interactions during wound infections. Here we show that E. coli kills Staphylococci, including S. aureus, both in vitro and in a mouse excisional wound model via the genotoxin, colibactin. Colibactin biosynthesis is encoded by the pks locus, which we identified in nearly 30% of human E. coli wound infection isolates. While it is not clear how colibactin is released from E. coli or how it penetrates target cells, we found that the colibactin intermediate N-myristoyl-D-Asn (NMDA) disrupts the S. aureus membrane. We also show that the BarA-UvrY two component system (TCS) senses the environment created during E. coli and S. aureus mixed species interaction, leading to upregulation of pks island genes. Further, we show that BarA-UvrY acts via the carbon storage global regulatory (Csr) system to control pks expression. Together, our data demonstrate the role of colibactin in interspecies competition and show that it is regulated by BarA-UvrY TCS during interspecies competition. Wound infections are often polymicrobial in nature and are associated with poor disease prognoses. Escherichia coli and Staphylococcus aureus are among the top five most cultured pathogens from wound infections. However, little is known about the polymicrobial interactions between E. coli and S. aureus during wound infections. In this study, we show that E. coli kills S. aureus both in vitro and in a mouse excisional wound model via the genotoxin, colibactin. We also show that the BarA-UvrY two component system (TCS) regulates the pks island during this mixed species interaction, acting through the carbon storage global regulatory (Csr) system to control colibactin production. Together, our data demonstrate the role of colibactin in interspecies competition and show that it is regulated by BarA-UvrY TCS during interspecies competition.
Collapse
Affiliation(s)
- Jun Jie Wong
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- Singapore Centre for Environmental Life Sciences Engineering, Interdisciplinary Graduate Programme, Nanyang Technological University, Singapore, Singapore
| | - Foo Kiong Ho
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
| | - Pei Yi Choo
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
| | - Kelvin K. L. Chong
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- Nanyang Technological University Institute for Health Technologies, Interdisciplinary Graduate School, Nanyang Technological University, Singapore, Singapore
| | - Chee Meng Benjamin Ho
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, Singapore
| | - Ramesh Neelakandan
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Damien Keogh
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
| | - Timothy Barkham
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Department of Laboratory Medicine, Tan Tock Seng Hospital, Singapore, Singapore
| | - John Chen
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Chuan Fa Liu
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Kimberly A. Kline
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
- * E-mail:
| |
Collapse
|
19
|
Clement RGE, Hall AC, Wong SJ, Howie SEM, Simpson AHRW. Septic arthritis in an in vivo murine model induced by Staphylococcus aureus : a comparison between actions of the haemolysin toxin and the effects of the host immune response. Bone Joint Res 2022; 11:669-678. [PMID: 36066341 PMCID: PMC9533245 DOI: 10.1302/2046-3758.119.bjr-2022-0016.r1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Aims Staphylococcus aureus is a major cause of septic arthritis, and in vitro studies suggest α haemolysin (Hla) is responsible for chondrocyte death. We used an in vivo murine joint model to compare inoculation with wild type S. aureus 8325-4 with a Hla-deficient strain DU1090 on chondrocyte viability, tissue histology, and joint biomechanics. The aim was to compare the actions of S. aureus Hla alone with those of the animal’s immune response to infection. Methods Adult male C57Bl/6 mice (n = 75) were randomized into three groups to receive 1.0 to 1.4 × 107 colony-forming units (CFUs)/ml of 8325-4, DU1090, or saline into the right stifle joint. Chondrocyte death was assessed by confocal microscopy. Histological changes to inoculated joints were graded for inflammatory responses along with gait, weight changes, and limb swelling. Results Chondrocyte death was greater with 8325-4 (96.2% (SD 5.5%); p < 0.001) than DU1090 (28.9% (SD 16.0%); p = 0.009) and both were higher than controls (3.8% (SD 1.2%)). Histology revealed cartilage/bone damage with 8325-4 or DU1090 compared to controls (p = 0.010). Both infected groups lost weight (p = 0.006 for both) and experienced limb swelling (p = 0.043 and p = 0.018, respectively). Joints inoculated with bacteria showed significant alterations in gait cycle with a decreased stance phase, increased swing phase, and a corresponding decrease in swing speed. Conclusion Murine joints inoculated with Hla-producing 8325-4 experienced significantly more chondrocyte death than those with DU1090, which lack the toxin. This was despite similar immune responses, indicating that Hla was the major cause of chondrocyte death. Hla-deficient DU1090 also elevated chondrocyte death compared to controls, suggesting a smaller additional deleterious role of the immune system on cartilage. Cite this article: Bone Joint Res 2022;11(9):669–678.
Collapse
Affiliation(s)
- Rhys G E Clement
- Department of Orthopaedics and Trauma, University of Edinburgh, Edinburgh, UK
| | - Andrew C Hall
- Deanery of Biomedical Sciences, The University of Edinburgh, Edinburgh, UK
| | - Seng J Wong
- Department of Orthopaedic Surgery, Singapore General Hospital, Singapore, Singapore
| | - Sarah E M Howie
- MRC Centre for Inflammation Research, University of Edinburgh, Edinburgh, UK
| | | |
Collapse
|
20
|
Wang H, Shen J, Ma K, Zhu C, Fang M, Hou X, Zhang S, Wang W, Xue T. Transcriptome analysis revealed the role of capsular polysaccharides in desiccation tolerance of foodborne Staphylococcus aureus. Food Res Int 2022; 159:111602. [DOI: 10.1016/j.foodres.2022.111602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 06/24/2022] [Accepted: 06/28/2022] [Indexed: 11/04/2022]
|
21
|
Suárez CA, Carrasco ST, Brandolisio FNA, Abatangelo V, Boncompain CA, Peresutti-Bacci N, Morbidoni HR. Bioinformatic Analysis of a Set of 14 Temperate Bacteriophages Isolated from Staphylococcus aureus Strains Highlights Their Massive Genetic Diversity. Microbiol Spectr 2022; 10:e0033422. [PMID: 35880893 PMCID: PMC9430571 DOI: 10.1128/spectrum.00334-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Accepted: 07/04/2022] [Indexed: 11/20/2022] Open
Abstract
Epidemiology and virulence studies of Staphylococcus aureus showed that temperate bacteriophages are one of the most powerful drivers for its evolution not only because of their abundance but also because of the richness of their genetic payload. Here, we report the isolation, genome sequencing, and bioinformatic analysis of 14 bacteriophages induced from lysogenic S. aureus strains from human or veterinary (cattle) origin. The bacteriophages belonged to the Siphoviridae family; were of similar genome size (40 to 45 kbp); and fell into clusters B2, B3, B5, and B7 according to a recent clustering proposal. One of the phages, namely, vB_SauS_308, was the most unusual one, belonging to the sparsely populated subcluster B7 but showing differences in protein family contents compared with the rest of the members. This phage contains a type I endolysin (one catalytic domain and noncanonical cell wall domain [CBD]) and a host recognition module lacking receptor binding protein, cell wall hydrolase, and tail fiber proteins. This phage also lacked virulence genes, which is opposite to what has been reported for subcluster B6 and B7 members. None of six phages, taken as representatives of each of the four subclusters, showed activity on coagulase-negative staphylococci (excepted for two Staphylococcus hominis strains in which propagation and a very slow adsorption rate were observed) nor transducing ability. Immunity tests on S. aureus RN4220 lysogens with each of these phages showed no cross immunity. IMPORTANCE To the best of our knowledge, this set of sequenced bacteriophages is the largest one in South America. Our report describes for the first time the utilization of MultiTwin software to analyze the relationship between phage protein families. Notwithstanding the fact that most of the genetic information obtained correlated with recently published information, due to their geographical origin, the reported analysis adds up to and confirms currently available knowledge of Staphylococcus aureus temperate bacteriophages in terms of phylogeny and role in host evolution.
Collapse
Affiliation(s)
- Cristian A. Suárez
- Laboratorio de Microbiología Molecular, Facultad de Ciencias Médicas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Soledad T. Carrasco
- Laboratorio de Microbiología Molecular, Facultad de Ciencias Médicas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Facundo N. A. Brandolisio
- Laboratorio de Microbiología Molecular, Facultad de Ciencias Médicas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Virginia Abatangelo
- Laboratorio de Microbiología Molecular, Facultad de Ciencias Médicas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Carina A. Boncompain
- Laboratorio de Microbiología Molecular, Facultad de Ciencias Médicas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Natalia Peresutti-Bacci
- Laboratorio de Microbiología Molecular, Facultad de Ciencias Médicas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Héctor R. Morbidoni
- Laboratorio de Microbiología Molecular, Facultad de Ciencias Médicas, Universidad Nacional de Rosario, Rosario, Argentina
| |
Collapse
|
22
|
Antibiotic Exposure Leads to Reduced Phage Susceptibility in Vancomycin Intermediate Staphylococcus aureus (VISA). Antimicrob Agents Chemother 2022; 66:e0224721. [PMID: 35708333 PMCID: PMC9295574 DOI: 10.1128/aac.02247-21] [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: 12/05/2022] Open
Abstract
In the time of antimicrobial resistance, phage therapy is frequently suggested as a possible solution for such difficult-to-treat infections. Vancomycin-intermediate Staphylococcus aureus (VISA) remains a relatively rare yet increasing occurrence in the clinic for which phage therapy may be an option. However, the data presented herein suggest a potential cross-resistance mechanism to phage following vancomycin exposure in VISA strains. When comparing genetically similar strains differing in their susceptibility to vancomycin, those with intermediate levels of vancomycin resistance displayed decreased sensitivity to phage in solid and liquid assays. Serial passaging with vancomycin induced both reduced vancomycin susceptibility and phage sensitivity. As a consequence, the process of phage infection was shown to be interrupted after DNA ejection from adsorbed phage but prior to phage DNA replication, as demonstrated through adsorption assays, lysostaphin sensitivity assays, electron microscopy, and quantitative PCR (qPCR). At a time when phage products are being used for experimental treatments and tested in clinical trials, it is important to understand possible interference between mechanisms underlying antibiotic and phage resistance in order to design effective therapeutic regimens.
Collapse
|
23
|
Chen H, Yang N, Yu L, Li J, Zhang H, Zheng Y, Xu M, Liu Y, Yang Y, Li J. Synergistic Microbicidal Effect of AUR and PEITC Against Staphylococcus aureus Skin Infection. Front Cell Infect Microbiol 2022; 12:927289. [PMID: 35774400 PMCID: PMC9237442 DOI: 10.3389/fcimb.2022.927289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Accepted: 05/11/2022] [Indexed: 11/13/2022] Open
Abstract
Given the increasing prevalence of Staphylococcus aureus antibiotic resistance, there is an urgent need to repurpose approved drugs with known pharmacology and toxicology as an alternative therapeutic strategy. We have reported that the sustained monotherapy of auranofin (AUR) inevitably resulted in reduced susceptibility or even the emergence of resistance to AUR in S. aureus. However, whether drug combination could increase antibacterial activity while preventing AUR resistance is still unknown. Here, we focused on the important role of AUR combined with phenethyl isothiocyanate (PEITC) in skin infection and determined the synergistic antimicrobial effect on S. aureus by using checkerboard assays and time-kill kinetics analysis. This synergistic antimicrobial activity correlated with increased reactive oxygen species (ROS) generation, disruption of bacterial cell structure, and inhibition of biofilm formation. We also showed that AUR synergized with PEITC effectively restored the susceptibility to AUR via regulating thioredoxin reductase (TrxR) and rescued mice from subcutaneous abscesses through eliminating S. aureus pathogens, including methicillin-resistant S. aureus (MRSA). Collectively, our study indicated that the AUR and PEITC combination had a synergistic antimicrobial impact on S. aureus in vitro and in vivo. These results suggest that AUR and PEITC treatment may be a promising option for S. aureus infection.
Collapse
Affiliation(s)
- Haoran Chen
- Department of Infectious Disease, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Ning Yang
- Department of Infectious Disease, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Liang Yu
- Department of Infectious Disease, The First Affiliated Hospital of Anhui Medical University, Hefei, China
- Anhui Center for Surveillance of Bacterial Resistance, Hefei, China
- Institute of Bacterial Resistance, Anhui Medical University, Hefei, China
| | - Jiajia Li
- The Center for Scientific Research, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Hui Zhang
- Department of Infectious Disease, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Yahong Zheng
- Department of Infectious Disease, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Mengran Xu
- Department of Infectious Disease, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Yanyan Liu
- Department of Infectious Disease, The First Affiliated Hospital of Anhui Medical University, Hefei, China
- Anhui Center for Surveillance of Bacterial Resistance, Hefei, China
- Institute of Bacterial Resistance, Anhui Medical University, Hefei, China
| | - Yi Yang
- Department of Infectious Disease, The First Affiliated Hospital of Anhui Medical University, Hefei, China
- *Correspondence: Yi Yang, ; Jiabin Li,
| | - Jiabin Li
- Department of Infectious Disease, The First Affiliated Hospital of Anhui Medical University, Hefei, China
- Anhui Center for Surveillance of Bacterial Resistance, Hefei, China
- Institute of Bacterial Resistance, Anhui Medical University, Hefei, China
- *Correspondence: Yi Yang, ; Jiabin Li,
| |
Collapse
|
24
|
Ibarra-Chávez R, Brady A, Chen J, Penadés JR, Haag AF. Phage-inducible chromosomal islands promote genetic variability by blocking phage reproduction and protecting transductants from phage lysis. PLoS Genet 2022; 18:e1010146. [PMID: 35344558 PMCID: PMC8989297 DOI: 10.1371/journal.pgen.1010146] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 04/07/2022] [Accepted: 03/14/2022] [Indexed: 11/18/2022] Open
Abstract
Phage-inducible chromosomal islands (PICIs) are a widespread family of highly mobile genetic elements that disseminate virulence and toxin genes among bacterial populations. Since their life cycle involves induction by helper phages, they are important players in phage evolution and ecology. PICIs can interfere with the lifecycle of their helper phages at different stages resulting frequently in reduced phage production after infection of a PICI-containing strain. Since phage defense systems have been recently shown to be beneficial for the acquisition of exogenous DNA via horizontal gene transfer, we hypothesized that PICIs could provide a similar benefit to their hosts and tested the impact of PICIs in recipient strains on host cell viability, phage propagation and transfer of genetic material. Here we report an important role for PICIs in bacterial evolution by promoting the survival of phage-mediated transductants of chromosomal or plasmid DNA. The presence of PICIs generates favorable conditions for population diversification and the inheritance of genetic material being transferred, such as antibiotic resistance and virulence genes. Our results show that by interfering with phage reproduction, PICIs can protect the bacterial population from phage attack, increasing the overall survival of the bacterial population as well as the transduced cells. Moreover, our results also demonstrate that PICIs reduce the frequency of lysogenization after temperate phage infection, creating a more genetically diverse bacterial population with increased bet-hedging opportunities to adapt to new niches. In summary, our results identify a new role for the PICIs and highlight them as important drivers of bacterial evolution.
Collapse
Affiliation(s)
- Rodrigo Ibarra-Chávez
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Department of Biology, Section of Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Aisling Brady
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, United Kingdom
| | - John Chen
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - José R. Penadés
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, United Kingdom
- Universidad CEU Cardenal Herrera, Moncada, Spain
| | - Andreas F. Haag
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- School of Medicine, University of St Andrews, North Haugh, St Andrews, United Kingdom
| |
Collapse
|
25
|
Garrett SR, Mariano G, Palmer T. Genomic analysis of the progenitor strains of Staphylococcus aureus RN6390. Access Microbiol 2022; 4:000464.v3. [PMID: 36910860 PMCID: PMC9996129 DOI: 10.1099/acmi.0.000464.v3] [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: 06/21/2022] [Accepted: 09/14/2022] [Indexed: 12/03/2022] Open
Abstract
RN6390 is a commonly used laboratory strain of Staphylococcus aureus derived from NCTC8325. In this study, we sequenced the RN6390 genome and compared it to available genome sequences for NCTC8325. We confirmed that three prophages, Φ11, Φ12 and Φ13, which are present in NCTC8325 are absent from the genome of RN6390, consistent with the successive curing events leading to the generation of this strain. However, we noted that a separate prophage is present in RN6390 that is not found in NCTC8325. Two separate genome sequences have been deposited for the parental strain, NCTC8325. Analysis revealed several differences between these sequences, in particular, between the copy number of esaG genes, which encode immunity proteins to the type VII secreted anti-bacterial toxin, EsaD. Single nucleotide polymorphisms were also detected in ribosomal RNA genes and genes encoding microbial surface components recognizing adhesive matrix molecules (MSCRAMM) between the two NCTC8325 sequences. Comparing each NCTC8325 sequence to other strains in the RN6390 lineage confirmed that sequence assembly errors in the earlier NCTC8325 sequence are the most likely explanation for most of the differences observed.
Collapse
Affiliation(s)
- Stephen R Garrett
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Giuseppina Mariano
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Tracy Palmer
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| |
Collapse
|
26
|
Abstract
Bacterial pathogens commonly carry prophages that express virulence factors, and human strains of Staphylococcus aureus carry Sa3int phages, which promote immune evasion. Recently, however, these phages have been found in livestock-associated, methicillin-resistant S. aureus (LA-MRSA). This is surprising, as LA-MRSA strains contain a mutated primary bacterial integration site, which likely explains why the rare integration events that do occur mostly happen at alternative locations. Using deep sequencing, we show that after initial integration at secondary sites, Sa3int phages adapt through nucleotide changes in their attachment sequences to increase homology with alternative bacterial attachment sites. Importantly, this homology significantly enhances integrations in new rounds of infections. We propose that promiscuity of the phage-encoded tyrosine recombinase is responsible for establishment of Sa3int phages in LA-MRSA. Our results demonstrate that phages can adopt extensive population heterogeneity, leading to establishment in strains lacking bona fide integration sites. Ultimately, their presence may increase virulence and zoonotic potential of pathogens with major implications for human health.
Collapse
|
27
|
Staphylococcus aureus Efflux Pumps and Tolerance to Ciprofloxacin and Chlorhexidine following Induction by Mupirocin. Antimicrob Agents Chemother 2021; 66:e0184521. [PMID: 34930023 DOI: 10.1128/aac.01845-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mupirocin induced expression of genes encoding efflux pumps NorA and MepA as well as a YFP fluorescence reporter of NorA. Mupirocin exposure also produced reduced susceptibility to pump substrates ciprofloxacin and chlorhexidine, a change that was dependent on intact norA and mepA, respectively.
Collapse
|
28
|
Maurin C, Courrier E, He Z, Rigaill J, Josse J, Laurent F, Gain P, Thuret G, Verhoeven PO. Key Role of Staphylococcal Fibronectin-Binding Proteins During the Initial Stage of Staphylococcus aureus Keratitis in Humans. Front Cell Infect Microbiol 2021; 11:745659. [PMID: 34858871 PMCID: PMC8630648 DOI: 10.3389/fcimb.2021.745659] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 10/04/2021] [Indexed: 12/25/2022] Open
Abstract
Objectives Staphylococcus aureus is one of the main causes of bacterial keratitis in humans. This study was aimed at investigating the mechanisms of S. aureus adhesion to the human corneal epithelium involved during the initial stage of infectious keratitis. Methods Human corneas stored in a specific active storage machine that restores a normal pluristratified epithelium were used to assess S. aureus adhesion level to intact and injured tissues using immunostaining. S. aureus adhesion to immobilized fibronectin was measured in microtiter plate. Internalization of S. aureus clinical isolates recovered from keratitis was assessed on human corneal epithelial HCE-2 cells. Results Superficial corneal injury unmasked fibronectin molecules expressed within the human corneal epithelium. S. aureus adhesion level was increased by 117-fold in the area of injured epithelium (p < 0.0001). The deletion of staphylococcal fnbA/B genes decreased by 71% the adhesion level to immobilized fibronectin (p < 0.001). The deletion of fnbA/B genes and the incubation of the corneas with anti-fibronectin blocking antibodies prior to the infection significantly reduced the S. aureus adhesion level to injured corneal epithelium (p < 0.001). Finally, S. aureus clinical isolates triggered its internalization in human corneal epithelial cells as efficiently as the 8325-4 wt. Conclusion S. aureus was almost unable to bind the intact corneal epithelium, whereas a superficial epithelial injury of the corneal epithelium strongly increased S. aureus adhesion, which is mainly driven by the interaction between staphylococcal fibronectin-binding proteins and unmasked fibronectin molecules located underneath the most superficial layer of the corneal epithelium.
Collapse
Affiliation(s)
- Corantin Maurin
- Corneal Graft Biology, Engineering and Imaging Laboratory (BiiGC), University of St-Etienne, St-Etienne, France
| | - Emilie Courrier
- Corneal Graft Biology, Engineering and Imaging Laboratory (BiiGC), University of St-Etienne, St-Etienne, France
| | - Zhiguo He
- Corneal Graft Biology, Engineering and Imaging Laboratory (BiiGC), University of St-Etienne, St-Etienne, France
| | - Josselin Rigaill
- CIRI, Centre International de Recherche en Infectiologie, GIMAP Team, University of Lyon, University of St-Etienne, INSERM U1111, CNRS UMR5308, ENS de Lyon, UCBL1, St-Etienne, France.,Laboratory of Infectious Agents and Hygiene, University Hospital of St-Etienne, St-Etienne, France
| | - Jérôme Josse
- CIRI, Centre International de Recherche en Infectiologie, Staphylococcal Pathogenesis Team, University of Lyon, INSERM U1111, CNRS UMR5308, ENS de Lyon, UCBL1, Lyon, France
| | - Frédéric Laurent
- CIRI, Centre International de Recherche en Infectiologie, Staphylococcal Pathogenesis Team, University of Lyon, INSERM U1111, CNRS UMR5308, ENS de Lyon, UCBL1, Lyon, France.,Department of Bacteriology, Institute for Infectious Agents, Hospices Civiles de Lyon, Lyon, France.,Centre National de Référence des Staphylocoques, Hospices Civils de Lyon, Lyon, France
| | - Philippe Gain
- Corneal Graft Biology, Engineering and Imaging Laboratory (BiiGC), University of St-Etienne, St-Etienne, France.,Department of Ophthalmology, University Hospital, St-Etienne, France
| | - Gilles Thuret
- Corneal Graft Biology, Engineering and Imaging Laboratory (BiiGC), University of St-Etienne, St-Etienne, France.,Department of Ophthalmology, University Hospital, St-Etienne, France
| | - Paul O Verhoeven
- CIRI, Centre International de Recherche en Infectiologie, GIMAP Team, University of Lyon, University of St-Etienne, INSERM U1111, CNRS UMR5308, ENS de Lyon, UCBL1, St-Etienne, France.,Laboratory of Infectious Agents and Hygiene, University Hospital of St-Etienne, St-Etienne, France
| |
Collapse
|
29
|
Microbial Efflux Pump Inhibitors: A Journey around Quinoline and Indole Derivatives. Molecules 2021; 26:molecules26226996. [PMID: 34834098 PMCID: PMC8618814 DOI: 10.3390/molecules26226996] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 11/12/2021] [Accepted: 11/17/2021] [Indexed: 11/29/2022] Open
Abstract
Antimicrobial resistance (AMR) is a complex threat to human health and, to date, it represents a hot topic in drug discovery. The use of non-antibiotic molecules to block resistance mechanisms is a powerful alternative to the identification of new antibiotics. Bacterial efflux pumps exert the early step of AMR development, allowing the bacteria to grow in presence of sub-inhibitory drug concentration and develop more specific resistance mechanisms. Thus, efflux pump inhibitors (EPIs) offer a great opportunity to fight AMR, potentially restoring antibiotic activity. Based on our experience in designing and synthesizing novel EPIs, herein, we retrieved information around quinoline and indole derivatives reported in literature on this topic. Thus, our aim was to collect all data around these promising classes of EPIs in order to delineate a comprehensive structure–activity relationship (SAR) around each core for different microbes. With this review article, we aim to help future research in the field in the discovery of new microbial EPIs with improved activity and a better safety profile.
Collapse
|
30
|
Dynamics of Antibacterial Drone Establishment in Staphylococcus aureus: Unexpected Effects of Antibiotic Resistance Genes. mBio 2021; 12:e0208321. [PMID: 34781740 PMCID: PMC8593670 DOI: 10.1128/mbio.02083-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The antibacterial drone (ABD) system is based on repurposing the phage-inducible staphylococcal pathogenicity islands (SaPIs) for use as antibacterial agents that are indifferent to antibiotic resistance. The ABDs were constructed by inserting tetM for tetracycline resistance (Tcr) selection, replacing the SaPI virulence genes with bactericidal or bacteriostatic genes such as CRISPR/cas9/agrA, whose expression kills by double-strand cleavage of agrA, or CRISPR/dcas9/agrP2P3, whose expression blocks the target organism's virulence. ABD DNA is packaged in phage-like particles that attack their staphylococcal targets in vivo as well as in vitro. We determine ABD titers by transfer frequency, enumerate surviving cells as a function of multiplicity, and analyze the fate of ABD DNA with green fluorescent protein. An initial study revealed surprisingly that many more cells were killed by the ABD than were measured by transduction. Our study of this phenomenon has revealed several important features of the ABD system: (i) a significant number of entering ABD DNA molecules do not go on to establish stable transductants (i.e., are abortive); (ii) ABD cargo genes are expressed immediately following entry, even by the abortive ABDs; (iii) immediate plating on Tc-containing agar seriously underestimates particle numbers, partly owing to Tc inhibition of protein synthesis; (iv) replacement of tetM with cadA (conferring resistance to CdCl2) provides more accurate particle enumeration; (v) ABDs expressing CRISPR/cas9/agrA kill ∼99.99% of infected cells and provide the most accurate measurement of particle numbers as well as proof of principle for the system; and (vi) surprisingly, TetM interferes with stable establishment of ABD DNA independently of Tcr. IMPORTANCE For a particulate therapeutic agent, such as the ABD, accurate enumeration of particles is critical to enable evaluation of preparative procedures and calculation of therapeutic dosages. It is equally important that a selective marker used for these two purposes be biologically inert. We have long used tetM for these purposes but show here that tetM not only underestimates particle titers, by over 20-fold in some experiments, but also seriously impedes stable establishment of the therapeutic particle DNA. Given that tetM is a very convenient and widely used selective marker, publication of these findings is of considerable importance to the microbiological community as well as an interesting illustration of the unpredictable biological effects of genes taken out of their native context.
Collapse
|
31
|
Shape shifter: redirection of prolate phage capsid assembly by staphylococcal pathogenicity islands. Nat Commun 2021; 12:6408. [PMID: 34737316 PMCID: PMC8569155 DOI: 10.1038/s41467-021-26759-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 10/19/2021] [Indexed: 11/16/2022] Open
Abstract
Staphylococcus aureus pathogenicity islands (SaPIs) are molecular parasites that hijack helper phages for their transfer. SaPIbov5, the prototypical member of a family of cos type SaPIs, redirects the assembly of ϕ12 helper capsids from prolate to isometric. This size and shape shift is dependent on the SaPIbov5-encoded protein Ccm, a homolog of the ϕ12 capsid protein (CP). Using cryo-electron microscopy, we have determined structures of prolate ϕ12 procapsids and isometric SaPIbov5 procapsids. ϕ12 procapsids have icosahedral end caps with Tend = 4 architecture and a Tmid = 14 cylindrical midsection, whereas SaPIbov5 procapsids have T = 4 icosahedral architecture. We built atomic models for CP and Ccm, and show that Ccm occupies the pentameric capsomers in the isometric SaPIbov5 procapsids, suggesting that preferential incorporation of Ccm pentamers prevents the cylindrical midsection from forming. Our results highlight that pirate elements have evolved diverse mechanisms to suppress phage multiplication, including the acquisition of phage capsid protein homologs. Phage-inducible chromosomal islands (PICIs) are a group of mobile genetic elements that hijack the replication and assembly machinery of helper bacteriophages. Here the authors describe a mechanism by which a group of PICIs from Staphylococcus aureus re-direct the assembly pathway of their helpers using a capsid protein homolog.
Collapse
|
32
|
The role of mprF mutations in "see-saw effect" of Daptomycin-resistant methicillin-resistant Staphylococcus aureus isolates. Antimicrob Agents Chemother 2021; 66:e0129521. [PMID: 34662187 DOI: 10.1128/aac.01295-21] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The emergence of daptomycin-resistant (DAP-R) Staphylococcus aureus strains has become a global problem. Point mutations in mprF are the main cause of daptomycin (DAP) treatment failure. However, the impact of these specific point-mutations in methicillin-resistant S. aureus (MRSA) strains associated with DAP resistance and the "see-saw effect" of distinct beta-lactams remains unclear. In this study, we used three series of clinical MRSA strains with three distinct mutated mprF alleles from clone complexes (CC) 5 and 59 to explore the "see-saw effect" and the combination effect of DAP plus beta-lactams. Through construction of mprF deletion and complementation strains of SA268, we determined that mprF-S295A, mprF-S337L and one novel mutation of mprF-I348del within the bifunctional domain lead to DAP resistance. Compared with wild-type mprF cloned from a DAP-susceptible (DAP-S) strain, these three mprF mutations conferred the "see-saw effect" to distinct beta-lactams in the SA268ΔmprF strains and mutated-mprF (I348del and S337L) did not alter the cell surface positive charge (P > 0.05). The susceptibility to beta-lactams increased significantly in DAP-R CC59 strains and the "see-saw effect" was found to be associated with distinct mutated mprF alleles and the category of beta-lactams. The synergistic activity of DAP plus oxacillin was detected in all DAP-R MRSA strains. Continued progress in understanding the mechanism of restoring susceptibility to beta-lactam antibiotics mediated by the mprF mutation and its impact on beta-lactam combination therapy will provide fundamental insights into treatment of MRSA infections.
Collapse
|
33
|
Kristensen CS, Varming AK, Leinweber HAK, Hammer K, Lo Leggio L, Ingmer H, Kilstrup M. Characterization of the genetic switch from phage ɸ13 important for Staphylococcus aureus colonization in humans. Microbiologyopen 2021; 10:e1245. [PMID: 34713608 PMCID: PMC8516035 DOI: 10.1002/mbo3.1245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 09/30/2021] [Indexed: 11/09/2022] Open
Abstract
Temperate phages are bacterial viruses that after infection either reside integrated into a bacterial genome as prophages forming lysogens or multiply in a lytic lifecycle. The decision between lifestyles is determined by a switch involving a phage-encoded repressor, CI, and a promoter region from which lytic and lysogenic genes are divergently transcribed. Here, we investigate the switch of phage ɸ13 from the human pathogen Staphylococcus aureus. ɸ13 encodes several virulence factors and is prevalent in S. aureus strains colonizing humans. We show that the ɸ13 switch harbors a cI gene, a predicted mor (modulator of repression) gene, and three high-affinity operator sites binding CI. To quantify the decision between lytic and lysogenic lifestyle, we introduced reporter plasmids that carry the 1.3 kb switch region from ɸ13 with the lytic promoter fused to lacZ into S. aureus and Bacillus subtilis. Analysis of β-galactosidase expression indicated that decision frequency is independent of host factors. The white "lysogenic" phenotype, which relies on the expression of cI, could be switched to a stable blue "lytic" phenotype by DNA damaging agents. We have characterized lifestyle decisions of phage ɸ13, and our approach may be applied to other temperate phages encoding virulence factors in S. aureus.
Collapse
Affiliation(s)
- Camilla S. Kristensen
- Department of Biotechnology and BiomedicineTechnical University of DenmarkLyngbyDenmark
| | | | | | - Karin Hammer
- Department of Biotechnology and BiomedicineTechnical University of DenmarkLyngbyDenmark
| | - Leila Lo Leggio
- Department of ChemistryUniversity of CopenhagenKobenhavnDenmark
| | - Hanne Ingmer
- Department of Veterinary and Animal SciencesUniversity of CopenhagenKobenhavnDenmark
| | - Mogens Kilstrup
- Department of Biotechnology and BiomedicineTechnical University of DenmarkLyngbyDenmark
| |
Collapse
|
34
|
Vitzilaiou E, Kuria AM, Siegumfeldt H, Rasmussen MA, Knøchel S. The impact of bacterial cell aggregation on UV inactivation kinetics. WATER RESEARCH 2021; 204:117593. [PMID: 34482094 DOI: 10.1016/j.watres.2021.117593] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 07/14/2021] [Accepted: 08/19/2021] [Indexed: 06/13/2023]
Abstract
Reconditioning of food processing water streams for reuse is an increasingly common water management practice in the food industry and UV disinfection is often employed as part of the water treatment. Several factors may impact the effect of UV radiation. Here, we aim to assess the impact of cell aggregation on UV inactivation kinetics and investigate if UV exposure induces aggregation. Three strains, isolated from food processing water reuse lines (Raoultella ornithinolytica, Pseudomonas brenneri, Rothia mucilaginosa) and both an aggregating and a non-aggregating strain of Staphylococcus aureus were exposed to UVC light at 255 nm using UV LED equipment. Total Viable Count and phase-contrast microscopy, coupled with image analysis, were used to compare the UV inactivation kinetics with the average particle size for a range of UV doses. Tailing effect, seen as a strong reduction in inactivation rate, was observed for all strains at higher UV doses (industrial strains ≥ 50 or 120 mJ/cm2, S. aureus strains ≥ 40 or 60 mJ/cm2). The naturally aggregating strains were more UV tolerant, both within and between species. When aggregates of S. aureus were broken, UV tolerance decreased. For the processing water isolates, the lowest applied UV dose (25 mJ/cm2) significantly increased the average particle size. Application of higher UV doses obtained with longer exposure times did not further increase the particle size compared with untreated samples. For the S. aureus strains, however, no consistent change in average particle size was observed due to UV. Our results demonstrate that aggregating strains have a higher degree of protection and that UV radiation induces aggregation in some, but not all bacteria. A better understanding of the mechanisms governing microbial aggregation and survival during UV treatment could help to improve UV applications and predictions of microbial inactivation.
Collapse
Affiliation(s)
- Eirini Vitzilaiou
- Microbiology and Fermentation, Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 26, DK-1958, Frederiksberg C, Denmark.
| | - Asaph M Kuria
- Microbiology and Fermentation, Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 26, DK-1958, Frederiksberg C, Denmark
| | - Henrik Siegumfeldt
- Microbiology and Fermentation, Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 26, DK-1958, Frederiksberg C, Denmark
| | - Morten A Rasmussen
- Microbiology and Fermentation, Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 26, DK-1958, Frederiksberg C, Denmark; COPSAC, Copenhagen Prospective Studies on Asthma in Childhood, Herlev and Gentofte Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Susanne Knøchel
- Microbiology and Fermentation, Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 26, DK-1958, Frederiksberg C, Denmark
| |
Collapse
|
35
|
Miller RP, Berlouis ME, Hall AG, Simpson AHR, Smith IDM, Hall AC. Effects of Antibiotics on α-Toxin Levels during Staphylococcus aureus Culture: Implications for the Protection of Chondrocytes in a Model of Septic Arthritis. Cartilage 2021; 12:362-376. [PMID: 30762428 PMCID: PMC8236659 DOI: 10.1177/1947603519828433] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
OBJECTIVE Septic arthritis results from joint infection by Staphylococcus aureus, which produces potent α-toxin causing cell death, potentially leading to permanent cartilage damage. Treatment is by joint irrigation and antibiotics, although it is unclear if, following treatment with antibiotics which cause bacterial lysis, there is release of additional stored α-toxin. DESIGN A rabbit erythrocyte hemolysis assay was optimised to assess biologically-active α-toxin from cultured S. aureus α-toxin strain DU5946. Hemoglobin release was measured spectrophotometrically following addition of a bacteriostatic antibiotic (linezolid) or a bacteriolytic antibiotic (penicillin). A bovine cartilage model of septic arthritis was used to test the protective effects of antibiotics against S. aureus infection. RESULTS During S. aureus culture, α-toxin levels increased rapidly but the rate of rise was quickly (within 20 minutes) suppressed by linezolid (25 μg/mL). Penicillin also reduced the increase in α-toxin levels; however, the time course was relatively slow compared to linezolid even at high concentrations (50,000 U/mL). The efficacy of penicillin (250,000 U/mL) at reducing the rise in α-toxin was approximately 8% less than that of linezolid (P < 0.05) suggesting the presence of additional toxin. This could be due to a delayed action of penicillin, and/or release of a small pool of stored α-toxin from dying bacteria. In a bovine cartilage model, however, there was no difference between the protection of in situ chondrocytes against S. aureus by penicillin or linezolid (P > 0.05). CONCLUSION The results suggested that equally effective protection of chondrocytes against S. aureus septic arthritis may be obtained by the bacteriostatic or bacteriolytic antibiotics tested.
Collapse
Affiliation(s)
- Robbie P. Miller
- Centre for Integrative Physiology, Deanery of Biomedical Sciences, University of Edinburgh, Edinburgh, Scotland, UK
| | - Marie E. Berlouis
- Centre for Integrative Physiology, Deanery of Biomedical Sciences, University of Edinburgh, Edinburgh, Scotland, UK
| | - Alan G. Hall
- Centre for Integrative Physiology, Deanery of Biomedical Sciences, University of Edinburgh, Edinburgh, Scotland, UK
| | - A. Hamish R.W. Simpson
- Musculoskeletal Research Unit, Department of Orthopaedic Surgery, University of Edinburgh, Edinburgh, Scotland, UK
| | - Innes D. M. Smith
- Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, Scotland, UK
| | - Andrew C. Hall
- Centre for Integrative Physiology, Deanery of Biomedical Sciences, University of Edinburgh, Edinburgh, Scotland, UK,Andrew C. Hall, Centre for Integrative Physiology, Deanery of Biomedical Sciences, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9AG, Scotland, UK
| |
Collapse
|
36
|
Staphylococcus epidermidis Phages Transduce Antimicrobial Resistance Plasmids and Mobilize Chromosomal Islands. mSphere 2021; 6:6/3/e00223-21. [PMID: 33980677 PMCID: PMC8125051 DOI: 10.1128/msphere.00223-21] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Multidrug-resistant strains of S. epidermidis emerge in both nosocomial and livestock environments as the most important pathogens among coagulase-negative staphylococcal species. The study of transduction by phages is essential to understanding how virulence and antimicrobial resistance genes spread in originally commensal bacterial populations. Staphylococcus epidermidis is a leading opportunistic pathogen causing nosocomial infections that is notable for its ability to form a biofilm and for its high rates of antibiotic resistance. It serves as a reservoir of multiple antimicrobial resistance genes that spread among the staphylococcal population by horizontal gene transfer such as transduction. While phage-mediated transduction is well studied in Staphylococcus aureus, S. epidermidis transducing phages have not been described in detail yet. Here, we report the characteristics of four phages, 27, 48, 456, and 459, previously used for S. epidermidis phage typing, and the newly isolated phage E72, from a clinical S. epidermidis strain. The phages, classified in the family Siphoviridae and genus Phietavirus, exhibited an S. epidermidis-specific host range, and together they infected 49% of the 35 strains tested. A whole-genome comparison revealed evolutionary relatedness to transducing S. aureus phietaviruses. In accordance with this, all the tested phages were capable of transduction with high frequencies up to 10−4 among S. epidermidis strains from different clonal complexes. Plasmids with sizes from 4 to 19 kb encoding resistance to streptomycin, tetracycline, and chloramphenicol were transferred. We provide here the first evidence of a phage-inducible chromosomal island transfer in S. epidermidis. Similarly to S. aureus pathogenicity islands, the transfer was accompanied by phage capsid remodeling; however, the interfering protein encoded by the island was distinct. Our findings underline the role of S. epidermidis temperate phages in the evolution of S. epidermidis strains by horizontal gene transfer, which can also be utilized for S. epidermidis genetic studies. IMPORTANCE Multidrug-resistant strains of S. epidermidis emerge in both nosocomial and livestock environments as the most important pathogens among coagulase-negative staphylococcal species. The study of transduction by phages is essential to understanding how virulence and antimicrobial resistance genes spread in originally commensal bacterial populations. In this work, we provide a detailed description of transducing S. epidermidis phages. The high transduction frequencies of antimicrobial resistance plasmids and the first evidence of chromosomal island transfer emphasize the decisive role of S. epidermidis phages in attaining a higher pathogenic potential of host strains. To date, such importance has been attributed only to S. aureus phages, not to those of coagulase-negative staphylococci. This study also proved that the described transducing bacteriophages represent valuable genetic modification tools in S. epidermidis strains where other methods for gene transfer fail.
Collapse
|
37
|
Sultan AR, Lattwein KR, Lemmens-den Toom NA, Snijders SV, Kooiman K, Verbon A, van Wamel WJB. Paracetamol modulates biofilm formation in Staphylococcus aureus clonal complex 8 strains. Sci Rep 2021; 11:5114. [PMID: 33664312 PMCID: PMC7933145 DOI: 10.1038/s41598-021-84505-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 12/10/2020] [Indexed: 02/07/2023] Open
Abstract
Staphylococcus aureus biofilms are a major problem in modern healthcare due to their resistance to immune system defenses and antibiotic treatments. Certain analgesic agents are able to modulate S. aureus biofilm formation, but currently no evidence exists if paracetamol, often combined with antibiotic treatment, also has this effect. Therefore, we aimed to investigate if paracetamol can modulate S. aureus biofilm formation. Considering that certain regulatory pathways for biofilm formation and virulence factor production by S. aureus are linked, we further investigated the effect of paracetamol on immune modulator production. The in vitro biofilm mass of 21 S. aureus strains from 9 genetic backgrounds was measured in the presence of paracetamol. Based on biofilm mass quantity, we further investigated paracetamol-induced biofilm alterations using a bacterial viability assay combined with N-Acetylglucosamine staining. Isothermal microcalorimetry was used to monitor the effect of paracetamol on bacterial metabolism within biofilms and green fluorescent protein (GFP) promoter fusion technology for transcription of staphylococcal complement inhibitor (SCIN). Clinically relevant concentrations of paracetamol enhanced biofilm formation particularly among strains belonging to clonal complex 8 (CC8), but had minimal effect on S. aureus planktonic growth. The increase of biofilm mass can be attributed to the marked increase of N-Acetylglucosamine containing components of the extracellular matrix, presumably polysaccharide intercellular adhesion. Biofilms of RN6390A (CC8) showed a significant increase in the immune modulator SCIN transcription during co-incubation with low concentrations of paracetamol. Our data indicate that paracetamol can enhance biofilm formation. The clinical relevance needs to be further investigated.
Collapse
Affiliation(s)
- Andi R Sultan
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center Rotterdam, Rotterdam, The Netherlands.,Department of Microbiology, Faculty of Medicine, Hasanuddin University, Makassar, Indonesia
| | - Kirby R Lattwein
- Department of Biomedical Engineering, Thoraxcenter, Erasmus University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Nicole A Lemmens-den Toom
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Susan V Snijders
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Klazina Kooiman
- Department of Biomedical Engineering, Thoraxcenter, Erasmus University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Annelies Verbon
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Willem J B van Wamel
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center Rotterdam, Rotterdam, The Netherlands.
| |
Collapse
|
38
|
Brown AR, Ettefagh KA, Todd DA, Cole PS, Egan JM, Foil DH, Lacey EP, Cech NB. Bacterial efflux inhibitors are widely distributed in land plants. JOURNAL OF ETHNOPHARMACOLOGY 2021; 267:113533. [PMID: 33137433 DOI: 10.1016/j.jep.2020.113533] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 10/12/2020] [Accepted: 10/28/2020] [Indexed: 06/11/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Secondary metabolites play a critical role in plant defense against disease and are of great importance to ethnomedicine. Bacterial efflux pumps are active transport proteins that bacterial cells use to protect themselves against multiple toxic compounds, including many antimicrobials. Efflux pump inhibitors from plants can block these efflux pumps, increasing the potency of antimicrobial compounds. This study demonstrates that efflux pump inhibition against the Gram-positive bacterial pathogen Staphylococcus aureus is widespread in extracts prepared from individual species throughout the land plant lineage. It therefore suggests a general mechanism by which plants used by indigenous species may be effective as a topical treatment for some bacterial infections. AIM OF THE STUDY The goal of this research was to evaluate the distribution of efflux pump inhibitors in nine plant extracts with an ethnobotanical use suggestive of an antimicrobial function for the presence of efflux pump inhibitory activity against Staphylococcus aureus. MATERIALS AND METHODS Plants were collected, dried, extracted, and vouchers submitted to the Herbarium of the University of North Carolina Chapel Hill (NCU). The extracts were analyzed by quantitative mass spectrometry (UPLC-MS) to determine the presence and concentration of flavonoids with known efflux pump inhibitory activity. A mass spectrometry-based assay was employed to measure efflux pump inhibition for all extracts against Staphylococcus aureus. The assay relies on UPLC-MS measurement of changes in ethidium concentration in the spent culture broth when extracts are incubated with bacteria. RESULTS Eight of these nine plant extracts inhibited toxic compound efflux at concentrations below the MIC (minimum inhibitory concentration) value for the same extract. The most active extracts were those prepared from Osmunda claytoniana L. and Pinus strobes L., which both demonstrated IC50 values for efflux inhibition of 19 ppm. CONCLUSIONS Our findings indicate that efflux pump inhibitors active against Staphylococcus aureus are common in land plants. By extension, this activity is likely to be important in many plant-derived antimicrobial extracts, including those used in traditional medicine, and evaluation of efflux pump inhibition may often be valuable when studying natural product efficacy.
Collapse
Affiliation(s)
- Adam R Brown
- Department of Chemistry/Biochemistry, The University of North Carolina Greensboro, 435 Sullivan Bldg., Greensboro, NC, 27402, USA.
| | - Keivan A Ettefagh
- Department of Chemistry/Biochemistry, The University of North Carolina Greensboro, 435 Sullivan Bldg., Greensboro, NC, 27402, USA.
| | - Daniel A Todd
- Department of Chemistry/Biochemistry, The University of North Carolina Greensboro, 435 Sullivan Bldg., Greensboro, NC, 27402, USA.
| | - Patrick S Cole
- Department of Chemistry/Biochemistry, The University of North Carolina Greensboro, 435 Sullivan Bldg., Greensboro, NC, 27402, USA.
| | - Joseph M Egan
- Department of Chemistry/Biochemistry, The University of North Carolina Greensboro, 435 Sullivan Bldg., Greensboro, NC, 27402, USA.
| | - Daniel H Foil
- Department of Chemistry/Biochemistry, The University of North Carolina Greensboro, 435 Sullivan Bldg., Greensboro, NC, 27402, USA.
| | - Elizabeth P Lacey
- Department of Biology, The University of North Carolina Greensboro, 312 Eberhart Building, Greensboro, NC, 27402, USA.
| | - Nadja B Cech
- Department of Chemistry/Biochemistry, The University of North Carolina Greensboro, 435 Sullivan Bldg., Greensboro, NC, 27402, USA.
| |
Collapse
|
39
|
Shmidov E, Zander I, Lebenthal-Loinger I, Karako-Lampert S, Shoshani S, Banin E. An Efficient, Counter-Selection-Based Method for Prophage Curing in Pseudomonas aeruginosa Strains. Viruses 2021; 13:v13020336. [PMID: 33670076 PMCID: PMC7926659 DOI: 10.3390/v13020336] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 02/11/2021] [Accepted: 02/18/2021] [Indexed: 01/28/2023] Open
Abstract
Prophages are bacteriophages in the lysogenic state, where the viral genome is inserted within the bacterial chromosome. They contribute to strain genetic variability and can influence bacterial phenotypes. Prophages are highly abundant among the strains of the opportunistic pathogen Pseudomonas aeruginosa and were shown to confer specific traits that can promote strain pathogenicity. The main difficulty of studying those regions is the lack of a simple prophage-curing method for P. aeruginosa strains. In this study, we developed a novel, targeted-curing approach for prophages in P. aeruginosa. In the first step, we tagged the prophage for curing with an ampicillin resistance cassette (ampR) and further used this strain for the sacB counter-selection marker’s temporal insertion into the prophage region. The sucrose counter-selection resulted in different variants when the prophage-cured mutant is the sole variant that lost the ampR cassette. Next, we validated the targeted-curing with local PCR amplification and Whole Genome Sequencing. The application of the strategy resulted in high efficiency both for curing the Pf4 prophage of the laboratory wild-type (WT) strain PAO1 and for PR2 prophage from the clinical, hard to genetically manipulate, 39016 strain. We believe this method can support the research and growing interest in prophage biology in P. aeruginosa as well as additional Gram-negative bacteria.
Collapse
Affiliation(s)
- Esther Shmidov
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel; (E.S.); (I.Z.); (I.L.-L.); (S.S.)
- The Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Itzhak Zander
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel; (E.S.); (I.Z.); (I.L.-L.); (S.S.)
- The Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Ilana Lebenthal-Loinger
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel; (E.S.); (I.Z.); (I.L.-L.); (S.S.)
| | - Sarit Karako-Lampert
- Scientific Equipment Center, The Mina & Everard Goodman Faculty of Life Sciences Bar-Ilan University, Ramat Gan 5290002, Israel;
| | - Sivan Shoshani
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel; (E.S.); (I.Z.); (I.L.-L.); (S.S.)
- The Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Ehud Banin
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel; (E.S.); (I.Z.); (I.L.-L.); (S.S.)
- The Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan 5290002, Israel
- Correspondence:
| |
Collapse
|
40
|
Wibowo M, Gotfredsen CH, Sassetti E, Melchiorsen J, Clausen MH, Gram L, Ding L. Azodyrecins A-C: Azoxides from a Soil-Derived Streptomyces Species. JOURNAL OF NATURAL PRODUCTS 2020; 83:3519-3525. [PMID: 33216557 DOI: 10.1021/acs.jnatprod.0c00339] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Azoxy compounds belong to a small group of natural products sharing a common functional group with the general structure RN = N+(O-)R. Three new azoxides, azodyrecins A-C (1-3), were isolated from a soil-derived Streptomyces sp. strain P8-A2. The cis-alkenyl unit in 1-3 was found to readily isomerize to the trans-congeners (4-6). The structures of the new compounds were determined by detailed spectroscopic (1D/2D NMR) and HRMS data analysis. Azodyrecins belong to a new class of natural azoxy compounds and are proposed to derive from l-alanine and alkylamines. The absolute configurations of 1-6 were defined by comparison of ECD spectra. While no antimicrobial effects were observed for 1 against Staphylococcus aureus, Vibrio anguillarum, or Candida albicans, azodyrecin B (2) exhibited cytotoxicity against the human leukemia cell line HL-60 with an IC50 value of 2.2 μM.
Collapse
Affiliation(s)
- Mario Wibowo
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 221, DK-2800 Kongens Lyngby, Denmark
| | - Charlotte H Gotfredsen
- Department of Chemistry, Technical University of Denmark, Kemitorvet 207, DK-2800 Kongens Lyngby, Denmark
| | - Elisa Sassetti
- Center for Nanomedicine and Theranostics, Department of Chemistry, Technical University of Denmark, Kemitorvet 207, DK-2800 Kongens Lyngby, Denmark
| | - Jette Melchiorsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 221, DK-2800 Kongens Lyngby, Denmark
| | - Mads Hartvig Clausen
- Center for Nanomedicine and Theranostics, Department of Chemistry, Technical University of Denmark, Kemitorvet 207, DK-2800 Kongens Lyngby, Denmark
| | - Lone Gram
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 221, DK-2800 Kongens Lyngby, Denmark
| | - Ling Ding
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 221, DK-2800 Kongens Lyngby, Denmark
| |
Collapse
|
41
|
Schlesier T, Siegmund A, Rescher U, Heilmann C. Characterization of the Atl-mediated staphylococcal internalization mechanism. Int J Med Microbiol 2020; 310:151463. [PMID: 33197865 DOI: 10.1016/j.ijmm.2020.151463] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 09/16/2020] [Accepted: 10/22/2020] [Indexed: 12/18/2022] Open
Abstract
Staphylococcus aureus internalization by non-professional phagocytes is considered a main pathogenicity mechanism leading to chronic infections. The well-established mechanism of Staphylococcus aureus internalization is mediated by fibronectin (Fn)-binding proteins (FnBPs), Fn as a bridging molecule and the host cell α5β1 integrin. We previously identified a novel alternative internalization mechanism in Staphylococcus aureus, which involves the major autolysin Atl and the host cell heat shock cognate protein 70 (Hsc70). Atl-dependent internalization is also employed by the coagulase-negative Staphylococcus epidermidis, where it might represent the major or even sole internalization mechanism, because of the lack of FnBP-homologous proteins. In this study, we aimed to further characterize the Atl-dependent staphylococcal internalization mechanism. We performed biomolecular interaction analysis (BIA) to quantify the adhesive properties of Atl and found multivalent and high affinity interactions of Atl with Fn and Hsc70. Confocal laser scanning microscopy (CLSM) and a flow-cytometric internalization assay in combination with different pharmacological inhibitors suggested an involvement of the α5β1 integrin, Fn and Hsc70 and subsequent signaling events mediated by Src and phosphoinositide 3 (PI3) kinases in the Atl-dependent staphylococcal uptake by EA.hy 926 cells. Further characterization of the endocytic machinery implicated a role for clathrin-dependent receptor-mediated endocytosis involving actin cytoskeletal rearrangements and microtubules. In conclusion, Atl ubiquitous among staphylococcal species may substitute for the FnBPs ensuring low-level internalization via a mechanism that seems to share important features with the FnBP-mediated staphylococcal uptake potentially being the prerequisite for the development of therapy-resistant chronic infections by staphylococcal strains that lack FnBPs.
Collapse
Affiliation(s)
- Tim Schlesier
- Institute of Medical Microbiology, D-48149, Münster, Germany
| | - Anke Siegmund
- Institute of Medical Microbiology, University Hospital of Jena, D-07747, Jena, Germany
| | - Ursula Rescher
- Institute of Medical Biochemistry, Center for Molecular Biology of Inflammation (ZMBE), D-48149, Münster, Germany; Interdisciplinary Center for Clinical Research (IZKF), University Hospital of Münster, D-48149, Münster, Germany
| | - Christine Heilmann
- Institute of Medical Microbiology, D-48149, Münster, Germany; Interdisciplinary Center for Clinical Research (IZKF), University Hospital of Münster, D-48149, Münster, Germany.
| |
Collapse
|
42
|
Fernández L, Gutiérrez D, García P, Rodríguez A. Environmental pH is a key modulator of Staphylococcus aureus biofilm development under predation by the virulent phage phiIPLA-RODI. ISME JOURNAL 2020; 15:245-259. [PMID: 32963343 DOI: 10.1038/s41396-020-00778-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 09/03/2020] [Accepted: 09/14/2020] [Indexed: 11/09/2022]
Abstract
Previous work had shown that, in some Staphylococcus aureus strains, low concentrations of the virulent phage vB_SauM_phiIPLA-RODI (phiIPLA-RODI) promoted the formation of DNA-rich biofilms, whose cells exhibited significant transcriptional differences compared to an uninfected control. This study aimed to dissect the sequence of events leading to these changes. Analysis of phage propagation throughout biofilm development revealed that the number of phage particles increased steadily up to a certain point and then declined. This partial phage inactivation seemed to be a consequence of medium acidification due to glucose fermentation by the bacterium. Computer simulation of phage-host dynamics during biofilm development showed how even small differences in pH evolution can affect the outcome of phage infection. An acidic pH, together with successful phage propagation, was also necessary to observe the phage-associated changes in biofilm architecture and in the transcriptional profile of the bacterial population. Altogether, this study shows how the dynamics between phage and host can be tightly coordinated through an environmental cue, even in the context of a complex biofilm population.
Collapse
Affiliation(s)
- Lucía Fernández
- Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300, Villaviciosa, Asturias, Spain. .,DairySafe Group, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain.
| | - Diana Gutiérrez
- Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300, Villaviciosa, Asturias, Spain.,Laboratory of Applied Biotechnology, Department of Applied Biosciences, Faculty of Bioscience engineering, Ghent University, 9000, Ghent, Belgium
| | - Pilar García
- Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300, Villaviciosa, Asturias, Spain.,DairySafe Group, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain
| | - Ana Rodríguez
- Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300, Villaviciosa, Asturias, Spain.,DairySafe Group, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain
| |
Collapse
|
43
|
Gaussia Luciferase as a Reporter for Quorum Sensing in Staphylococcus aureus. SENSORS 2020; 20:s20154305. [PMID: 32752273 PMCID: PMC7435925 DOI: 10.3390/s20154305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/23/2020] [Accepted: 07/30/2020] [Indexed: 11/16/2022]
Abstract
Gaussia luciferase (GLuc) is a secreted protein with significant potential for use as a reporter of gene expression in bacterial pathogenicity studies. To date there are relatively few examples of its use in bacteriology. In this study we show that GLuc can be functionally expressed in the human pathogen Staphylococcus aureus and furthermore show that it can be used as a biosensor for the agr quorum sensing (QS) system which employs autoinducing peptides to control virulence. GLuc was linked to the P3 promoter of the S. aureusagr operon. Biosensor strains were validated by evaluation of chemical agent-mediated activation and inhibition of agr. Use of GLuc enabled quantitative assessment of agr activity. This demonstrates the utility of Gaussia luciferase for in vitro monitoring of agr activation and inhibition.
Collapse
|
44
|
Li L, Wang G, Li Y, Francois P, Bayer AS, Chen L, Seidl K, Cheung A, Xiong YQ. Impact of the Novel Prophage ϕSA169 on Persistent Methicillin-Resistant Staphylococcus aureus Endovascular Infection. mSystems 2020; 5:e00178-20. [PMID: 32606024 PMCID: PMC7329321 DOI: 10.1128/msystems.00178-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 06/16/2020] [Indexed: 12/26/2022] Open
Abstract
Persistent methicillin-resistant Staphylococcus aureus (MRSA) endovascular infections are life-threatening syndromes with few therapeutic options. The potential impact of bacteriophages on the persistent outcome has not been well studied. In this study, we investigated the role of a novel prophage (ϕSA169) in MRSA persistence by using a lysogen-free clinically resolving bacteremia (RB) isolate and comparing it to a derivative which was obtained by infecting the RB strain with ϕSA169, which has been lysogenized in a clinical persistent MRSA bacteremia (PB) isolate. Similar to the PB isolate, the ϕSA169-lysogenized RB strain exhibited well-defined in vitro and in vivo phenotypic and genotypic signatures related to the persistent outcome, including earlier activation of global regulators (i.e., sigB, sarA, agr RNAIII, and sae); higher expression of a critical purine biosynthesis gene, purF; and higher growth rates accompanied by lower ATP levels and vancomycin (VAN) susceptibility and stronger δ-hemolysin and biofilm formation versus its isogenic parental RB isolate. Notably, the contribution of ϕSA169 in persistent outcome with VAN treatment was confirmed in an experimental infective endocarditis model. Taken together, these results indicate the critical role of the prophage ϕSA169 in persistent MRSA endovascular infections. Further studies are needed to identify the mechanisms of ϕSA169 in mediating the persistence, as well as establishing the scope of impact, of this prophage in other PB strains.IMPORTANCE Bacteriophages are viruses that invade the bacterial host, disrupt bacterial metabolism, and cause the bacterium to lyse. Because of its remarkable antibacterial activity and unique advantages over antibiotics, for instance, bacteriophage is specific for one species of bacteria and resistance to phage is less common than resistance to antibiotics. Indeed, bacteriophage therapy for treating infections due to multidrug-resistant pathogens in humans has become a research hot spot. However, it is also worth considering that bacteriophages are transferable and could cotransfer host chromosomal genes, e.g., virulence and antimicrobial resistance genes, while lysogenizing and integrating into the bacterial chromosome (prophage), thus playing a role in bacterial evolution and virulence. In the current study, we identified a novel prophage, ϕSA169, from a clinical persistent MRSA bacteremia isolate, and we determined that ϕSA169 mediated well-defined in vitro and in vivo phenotypic and genotypic signatures related to the persistent outcome, which may represent a unique and important persistent mechanism(s).
Collapse
Affiliation(s)
- Liang Li
- The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, USA
| | - Genzhu Wang
- The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, USA
| | - Yi Li
- The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, USA
| | | | - Arnold S Bayer
- The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, USA
- David Geffen School of Medicine at UCLA, Los Angeles, California, USA
- Department of Medicine, Division of Infectious Diseases, Harbor-UCLA Medical Center, Torrance, California, USA
| | - Liang Chen
- Center for Discovery and Innovation, Nutley, New Jersey, USA
| | - Kati Seidl
- University Hospital of Zurich, Zurich, Switzerland
| | | | - Yan Q Xiong
- The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, USA
- David Geffen School of Medicine at UCLA, Los Angeles, California, USA
- Department of Medicine, Division of Infectious Diseases, Harbor-UCLA Medical Center, Torrance, California, USA
| |
Collapse
|
45
|
Ibarra-Chávez R, Haag AF, Dorado-Morales P, Lasa I, Penadés JR. Rebooting Synthetic Phage-Inducible Chromosomal Islands: One Method to Forge Them All. BIODESIGN RESEARCH 2020; 2020:5783064. [PMID: 37849900 PMCID: PMC10530653 DOI: 10.34133/2020/5783064] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 04/17/2020] [Indexed: 10/19/2023] Open
Abstract
Phage-inducible chromosomal islands (PICIs) are a widespread family of mobile genetic elements, which have an important role in bacterial pathogenesis. These elements mobilize among bacterial species at extremely high frequencies, representing an attractive tool for the delivery of synthetic genes. However, tools for their genetic manipulation are limited and timing consuming. Here, we have adapted a synthetic biology approach for rapidly editing of PICIs in Saccharomyces cerevisiae based on their ability to excise and integrate into the bacterial chromosome of their cognate host species. As proof of concept, we engineered several PICIs from Staphylococcus aureus and Escherichia coli and validated this methodology for the study of the biology of these elements by generating multiple and simultaneous mutations in different PICI genes. For biotechnological purposes, we also synthetically constructed PICIs as Trojan horses to deliver different CRISPR-Cas9 systems designed to either cure plasmids or eliminate cells carrying the targeted genes. Our results demonstrate that the strategy developed here can be employed universally to study PICIs and enable new approaches for diagnosis and treatment of bacterial diseases.
Collapse
Affiliation(s)
- Rodrigo Ibarra-Chávez
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Andreas F. Haag
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Pedro Dorado-Morales
- Laboratory of Microbial Pathogenesis, Navarrabiomed, Complejo Hospitalario de Navarra-Universidad Pública de Navarra (UPNA), Instituto de Investigación Sanitaria de Navarra (IDISNA), 31008 Pamplona, Spain
| | - Iñigo Lasa
- Laboratory of Microbial Pathogenesis, Navarrabiomed, Complejo Hospitalario de Navarra-Universidad Pública de Navarra (UPNA), Instituto de Investigación Sanitaria de Navarra (IDISNA), 31008 Pamplona, Spain
| | - José R. Penadés
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| |
Collapse
|
46
|
Identification and Characterization of Staphylococcus delphini Internalization Pathway in Nonprofessional Phagocytic Cells. Infect Immun 2020; 88:IAI.00002-20. [PMID: 32094259 DOI: 10.1128/iai.00002-20] [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: 01/06/2020] [Accepted: 02/19/2020] [Indexed: 12/20/2022] Open
Abstract
The intracellular lifestyle of bacteria is widely acknowledged to be an important mechanism in chronic and recurring infection. Among the Staphylococcus genus, only Staphylococcus aureus and Staphylococcus pseudintermedius have been clearly identified as intracellular in nonprofessional phagocytic cells (NPPCs), for which the mechanism is mainly fibronectin-binding dependent. Here, we used bioinformatics tools to search for possible new fibronectin-binding proteins (FnBP-like) in other Staphylococcus species. We found a protein in Staphylococcus delphini called Staphylococcus delphini surface protein Y (SdsY). This protein shares 68% identity with the Staphylococcus pseudintermedius surface protein D (SpsD), 36% identity with S. aureus FnBPA, and 39% identity with S. aureus FnBPB. The SdsY protein possesses the typical structure of FnBP-like proteins, including an N-terminal signal sequence, an A domain, a characteristic repeated pattern, and an LPXTG cell wall anchor motif. The level of adhesion to immobilized fibronectin was significantly higher in all S. delphini strains tested than in the fibronectin-binding-deficient S. aureus DU5883 strain. By using a model of human osteoblast infection, the level of internalization of all strains tested was significantly higher than with the invasive-incompetent S. aureus DU5883. These findings were confirmed by phenotype restoration after transformation of DU5883 by a plasmid expression vector encoding the SdsY repeats. Additionally, using fibronectin-depleted serum and murine osteoblast cell lines deficient for the β1 integrin, the involvement of fibronectin and β1 integrin was demonstrated in S. delphini internalization. The present study demonstrates that additional staphylococcal species are able to invade NPPCs and proposes a method to identify FnBP-like proteins.
Collapse
|
47
|
Liu W, Boudry P, Bohn C, Bouloc P. Staphylococcus aureus pigmentation is not controlled by Hfq. BMC Res Notes 2020; 13:63. [PMID: 32033621 PMCID: PMC7007678 DOI: 10.1186/s13104-020-4934-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 02/01/2020] [Indexed: 02/04/2023] Open
Abstract
Objective The golden color of Staphylococcus aureus is due to the synthesis of carotenoid pigments. In Gram-negative bacteria, Hfq is a global posttranscriptional regulator, but its function in S. aureus remains obscure. The absence of Hfq in S. aureus was reported to correlate with production of carotenoid pigment leading to the conclusion that Hfq was a negative regulator of the yellow color. However, we reported the construction of hfq mutants in several S. aureus strains and never noticed any color change; we therefore revisited the question of Hfq implication in S. aureus pigmentation. Results The absence or accumulation of Hfq does not affect S. aureus pigmentation.
Collapse
Affiliation(s)
- Wenfeng Liu
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Pierre Boudry
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Chantal Bohn
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Philippe Bouloc
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France.
| |
Collapse
|
48
|
Depardieu F, Bikard D. Gene silencing with CRISPRi in bacteria and optimization of dCas9 expression levels. Methods 2020; 172:61-75. [PMID: 31377338 DOI: 10.1016/j.ymeth.2019.07.024] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 07/25/2019] [Accepted: 07/29/2019] [Indexed: 12/15/2022] Open
Abstract
The catalytic null mutant of the Cas9 endonuclease from the bacterial CRISPR immune system, known as dCas9, can be guided by a small RNA to bind DNA sequences of interest and block gene transcription in a strategy known as CRISPRi. This powerful gene silencing method has already been used in a large number of species and in high throughput screens. Here we provide detailed design rules, methods and novel vectors to perform CRISPRi experiments in S. aureus and in E. coli, using the well characterized dCas9 protein from S. pyogenes. In particular, we describe a vector based on plasmid pC194 which is broadly used in Firmicutes, as well as a vector based on the very broad host-range rolling circle plasmid pLZ12, reported to replicate in both Firmicutes and Proteobacteria. A potential caveat of adapting dCas9 tools to various bacterial species is that dCas9 was shown to be toxic when expressed too strongly. We describe a method to optimize the expression level of dCas9 in order to avoid toxicity while ensuring strong on-target repression activity. We demonstrate this method by optimizing a pLZ12 based vector originally developed for S. aureus so that it can work in E. coli. This article should provide all the resources required to perform CRISPRi experiments in a broad range of bacterial species.
Collapse
Affiliation(s)
| | - David Bikard
- Groupe de Biologie de Synthèse, Institut Pasteur, Paris 75015, France.
| |
Collapse
|
49
|
Balcázar JL. Implications of bacteriophages on the acquisition and spread of antibiotic resistance in the environment. Int Microbiol 2020; 23:475-479. [PMID: 32002743 DOI: 10.1007/s10123-020-00121-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 12/30/2019] [Accepted: 01/21/2020] [Indexed: 12/13/2022]
Abstract
Although bacteriophages (or simply phages) are the most abundant biological entities and have the potential to transfer genetic material between bacterial hosts, their contribution to the acquisition and spread of antibiotic resistance genes in the environment has not been extensively studied. The environment is continually exposed to a wide variety of pollutants from anthropogenic sources, which may promote horizontal gene transfer events, including those mediated by phages. Considering the significant and growing concern of antibiotic resistance, phages should be taken into consideration during the implementation of mitigation measures. This review is focused on the emergence and spread of antibiotic resistance in the environment, with a special emphasis on the role of phages.
Collapse
Affiliation(s)
- José Luis Balcázar
- Catalan Institute for Water Research (ICRA), 17003, Girona, Spain.
- University of Girona, 17004, Girona, Spain.
| |
Collapse
|
50
|
The Nature of Antibacterial Adaptive Immune Responses against Staphylococcus aureus Is Dependent on the Growth Phase and Extracellular Peptidoglycan. Infect Immun 2019; 88:IAI.00733-19. [PMID: 31685545 DOI: 10.1128/iai.00733-19] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 10/21/2019] [Indexed: 02/07/2023] Open
Abstract
Staphylococcus aureus has evolved different strategies to evade the immune response, which play an important role in its pathogenesis. The bacteria express and shed various cell wall components and toxins during different stages of growth that may affect the protective T cell responses to extracellular and intracellular S. aureus However, if and how the dendritic cell (DC)-mediated T cell response against S. aureus changes during growth of the bacterium remain elusive. In this study, we show that exponential-phase (EP) S. aureus bacteria were endocytosed very efficiently by human DCs, and these DCs strongly promoted production of the T cell polarizing factor interleukin-12 (IL-12). In contrast, stationary-phase (SP) S. aureus bacteria were endocytosed less efficiently by DCs, and these DCs produced small amounts of IL-12. The high level of IL-12 production induced by EP S. aureus led to the development of a T helper 1 (Th1) cell response, which was inhibited after neutralization of IL-12. Furthermore, preincubation with the staphylococcal cell wall component peptidoglycan (PGN), characteristically shed during the exponential growth phase, modulated the DC response to EP S. aureus PGN preincubation appeared to inhibit IL-12p35 expression, leading to downregulation of IL-12 and an increase of IL-23 production by DCs, enhancing Th17 cell development. Taken together, our data indicate that exponential-phase S. aureus bacteria induce a stronger IL-12-dependent Th1 cell response than stationary-phase S. aureus and that this Th1 cell response shifted toward a Th17 cell response in the presence of PGN.
Collapse
|