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Zhou X, Ma S, Xu Y, Sun C, Liao J, Song M, Li G, Yuchen L, Chen P, Hu Y, Wang Y, Yu B. Nicotine promotes Staphylococcus aureus-induced osteomyelitis by activating the Nrf2/Slc7a11 signaling axis. Int Immunopharmacol 2024; 135:112223. [PMID: 38772295 DOI: 10.1016/j.intimp.2024.112223] [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: 12/13/2023] [Revised: 05/03/2024] [Accepted: 05/05/2024] [Indexed: 05/23/2024]
Abstract
Although smoking is a significant risk factor for osteomyelitis, there is limited experimental evidence that nicotine, a key tobacco constituent, is associated with this condition, leaving its mechanistic implications uncharacterized. This study revealed that nicotine promotes Staphylococcus aureus-induced osteomyelitis by increasing Nrf2 and Slc7a11 expression in vivo and in vitro. Inhibition of Slc7a11 using Erastin augmented bacterial phagocytosis/killing capabilities and fortified antimicrobial responses in an osteomyelitis model. Moreover, untargeted metabolomic analysis demonstrated that Erastin mitigated the effects of nicotine on S. aureus-induced osteomyelitis by altering glutamate/glutathione metabolism. These findings suggest that nicotine aggravates S. aureus-induced osteomyelitis by activating the Nrf2/Slc7a11 signaling pathway and that Slc7a11 inhibition can counteract the detrimental health effects of nicotine.
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Affiliation(s)
- Xuyou Zhou
- Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, China; Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Sushuang Ma
- Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, China; Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China; Department of Orthopaedics, The Fifth Affiliated Hospital, Southerm Medical University, Guangzhou, China
| | - Yuan Xu
- Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, China; Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Chongkai Sun
- Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, China; Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Juncheng Liao
- Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, China; Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Mingrui Song
- Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, China; Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Guanzhi Li
- Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, China; Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Liu Yuchen
- Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, China; Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Peng Chen
- Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, China; Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China; Department of Orthopedics, Hainan General Hospital (Hainan Affiliated Hospital of Hainan Medical University), Haikou, China
| | - Yanjun Hu
- Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, China; Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Yutian Wang
- Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, China; Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China.
| | - Bin Yu
- Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, China; Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China.
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Functional mgrA Influences Genetic Changes within a Staphylococcus aureus Cell Population over Time. J Bacteriol 2022; 204:e0013822. [PMID: 36154359 DOI: 10.1128/jb.00138-22] [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
Prolonged survival in the host-bacteria microenvironment drives the selection of alternative cell types in Staphylococcus aureus, permitting quasi-dormant sub-populations to develop. These facilitate antibiotic tolerance, long-term growth, and relapse of infection. Small Colony Variants (SCV) are an important cell type associated with persistent infection but are difficult to study in vitro due to the instability of the phenotype and reversion to the normal cell type. We have previously reported that under conditions of growth in continuous culture over a prolonged culture time, SCVs dominated a heterogenous population of cell types and these SCVs harbored a mutation in the DNA binding domain of the gene for the transcription factor, mgrA. To investigate this specific cell type further, S. aureus WCH-SK2-ΔmgrA itself was assessed with continuous culture. Compared to the wild type, the mgrA mutant strain required fewer generations to select for SCVs. There was an increased rate of mutagenesis within the ΔmgrA strain compared to the wild type, which we postulate is the mechanism explaining the increased emergence of SCV selection. The mgrA derived SCVs had impeded metabolism, altered MIC to specific antibiotics and an increased biofilm formation compared to non-SCV strain. Whole genomic sequencing detected single nucleotide polymorphisms (SNP) in phosphoglucosamine mutase glmM and tyrosine recombinase xerC. In addition, several genomic rearrangements were detected which affected genes involved in important functions such as antibiotic and toxic metal resistance and pathogenicity. Thus, we propose a direct link between mgrA and the SCV phenotype. IMPORTANCE Within a bacterial population, a stochastically generated heterogeneity of phenotypes allows continual survival against current and future stressors. The generation of a sub-population of quasi-dormant Small Colony Variants (SCV) in Staphylococcus aureus is such a mechanism, allowing for persistent or relapse of infection despite initial intervention seemingly clearing the infection. The use of continuous culture under clinically relevant conditions has allowed us to introduce time to the growth system and selects SCV within the population. This study provides valuable insights into the generation of SCV which are not addressed in standard laboratory generated models and reveals new pathways for understanding persistent S. aureus infection which can potentially be targeted in future treatments of persistent S. aureus infection.
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Oberkampf M, Hamiot A, Altamirano-Silva P, Bellés-Sancho P, Tremblay YDN, DiBenedetto N, Seifert R, Soutourina O, Bry L, Dupuy B, Peltier J. c-di-AMP signaling is required for bile salt resistance, osmotolerance, and long-term host colonization by Clostridioides difficile. Sci Signal 2022; 15:eabn8171. [PMID: 36067333 PMCID: PMC9831359 DOI: 10.1126/scisignal.abn8171] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
To colonize the host and cause disease, the human enteropathogen Clostridioides difficile must sense, respond, and adapt to the harsh environment of the gastrointestinal tract. We showed that the production and degradation of cyclic diadenosine monophosphate (c-di-AMP) were necessary during different phases of C. difficile growth, environmental adaptation, and infection. The production of this nucleotide second messenger was essential for growth because it controlled the uptake of potassium and also contributed to biofilm formation and cell wall homeostasis, whereas its degradation was required for osmotolerance and resistance to detergents and bile salts. The c-di-AMP binding transcription factor BusR repressed the expression of genes encoding the compatible solute transporter BusAA-AB. Compared with the parental strain, a mutant lacking BusR was more resistant to hyperosmotic and bile salt stresses, whereas a mutant lacking BusAA was more susceptible. A short exposure of C. difficile cells to bile salts decreased intracellular c-di-AMP concentrations, suggesting that changes in membrane properties induce alterations in the intracellular c-di-AMP concentration. A C. difficile strain that could not degrade c-di-AMP failed to persist in a mouse gut colonization model as long as the wild-type strain did. Thus, the production and degradation of c-di-AMP in C. difficile have pleiotropic effects, including the control of osmolyte uptake to confer osmotolerance and bile salt resistance, and its degradation is important for host colonization.
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Affiliation(s)
- Marine Oberkampf
- Institut Pasteur, Université Paris Cité, UMR-CNRS 6047, Laboratoire Pathogenèse des Bactéries Anaérobies, F-75015 Paris, France
| | - Audrey Hamiot
- Institut Pasteur, Université Paris Cité, UMR-CNRS 6047, Laboratoire Pathogenèse des Bactéries Anaérobies, F-75015 Paris, France
| | - Pamela Altamirano-Silva
- Centro de Investigación en Enfermedades Tropicales, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Paula Bellés-Sancho
- Institut Pasteur, Université Paris Cité, UMR-CNRS 6047, Laboratoire Pathogenèse des Bactéries Anaérobies, F-75015 Paris, France
| | - Yannick D. N. Tremblay
- Institut Pasteur, Université Paris Cité, UMR-CNRS 6047, Laboratoire Pathogenèse des Bactéries Anaérobies, F-75015 Paris, France
| | - Nicholas DiBenedetto
- Massachusetts Host-Microbiome Center, Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Roland Seifert
- Institute of Pharmacology and Research Core Unit Metabolomics, Hannover Medical School, Hannover, Germany
| | - Olga Soutourina
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Lynn Bry
- Massachusetts Host-Microbiome Center, Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
- Clinical Microbiology Laboratory, Department of Pathology, Brigham and Women’s Hospital, Boston, MA, USA
| | - Bruno Dupuy
- Institut Pasteur, Université Paris Cité, UMR-CNRS 6047, Laboratoire Pathogenèse des Bactéries Anaérobies, F-75015 Paris, France
| | - Johann Peltier
- Institut Pasteur, Université Paris Cité, UMR-CNRS 6047, Laboratoire Pathogenèse des Bactéries Anaérobies, F-75015 Paris, France
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
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Uddin MJ, Ma CJ, Kim JC, Ahn J. Proteomics-based discrimination of differentially expressed proteins in antibiotic-sensitive and antibiotic-resistant Salmonella Typhimurium, Klebsiella pneumoniae, and Staphylococcus aureus. Arch Microbiol 2019; 201:1259-1275. [PMID: 31240342 DOI: 10.1007/s00203-019-01693-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Revised: 06/06/2019] [Accepted: 06/13/2019] [Indexed: 01/25/2023]
Abstract
This study was designed to compare the differentially expressed proteins between antibiotic-sensitive and antibiotic-resistant Salmonella Typhimurium, Klebsiella pneumonia, and Staphylococcus aureus. The susceptibilities of wild-type (WT), ciprofloxacin (CIP) and/or oxacillin (OXA)-induced, and clinically isolated resistant (CCARM) S. Typhimurium (STWT, STCIP, and STCCARM), K. pneumoniae (KPWT, KPCIP, and KPCCARM), and S. aureus (SAWT, SACIP, SAOXA, and SACCARM) to antibiotics were determined using broth microdilution assay. STCIP was highly resistant to piperacillin (MIC > 512 μg/ml), KPCIP was resistant to chloramphenicol (128 μg/ml) and norfloxacin (16 μg/ml), SACIP was resistant to fluoroquinolones (32 μg/ml), and SAOXA was resistant to ceftriaxone (32 μg/ml). The protein profiles of antibiotic-sensitive and antibiotic-resistant strains were determined using 2-DE analysis followed by LC-MS/MS. The commonly expressed proteins of STWT-STCIP, STWT-STCCARM, KPWT-KPCIP, KPWT-KPCCARM, SAWT-SACIP, SAWT-SAOXA, and SAWT-SACCARM were 763, 677, 677, 469, 261, 259, and 226, respectively. The unique protein spots were observed 57 (6.5%), 80 (11.5%), and 68 (13.9%), respectively, for STCCARM, KPCCARM, and SACCARM. The highly up-regulated protein, PrsA (10-fold), was observed in STCIP resistant to ciprofloxacin (128-fold), levofloxacin (32-fold), norfloxacin (64-fold), and piperacillin (> 16-fold). The up-regulated proteins (YadC, FimA, and RplB) in KPCIP resistant to chloramphenicol (> 32-fold), ciprofloxacin (32-fold), levofloxacin (6-fold), norfloxacin (128-fold), and sparfloxacin (64-fold). AcrB and RpoB were up-regulated in SACCARM resistant to multiple antibiotics. The differentially expressed proteins were related to the antibiotic resistance of STWT, STCIP, STCCARM, KPWT, KPCIP, KPCCARM, SAWT, SACIP, SAOXA, and SACCARM. The resistance-associated proteins could be useful biomarkers for detecting antibiotic-resistant pathogens.
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Affiliation(s)
- Md Jalal Uddin
- Department of Medical Biomaterials Engineering and Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon, Gangwon, 24341, Republic of Korea
| | - Choong Je Ma
- Department of Medical Biomaterials Engineering and Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon, Gangwon, 24341, Republic of Korea
| | - Jin-Chul Kim
- Department of Medical Biomaterials Engineering and Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon, Gangwon, 24341, Republic of Korea
| | - Juhee Ahn
- Department of Medical Biomaterials Engineering and Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon, Gangwon, 24341, Republic of Korea.
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Tosi T, Hoshiga F, Millership C, Singh R, Eldrid C, Patin D, Mengin-Lecreulx D, Thalassinos K, Freemont P, Gründling A. Inhibition of the Staphylococcus aureus c-di-AMP cyclase DacA by direct interaction with the phosphoglucosamine mutase GlmM. PLoS Pathog 2019; 15:e1007537. [PMID: 30668586 PMCID: PMC6368335 DOI: 10.1371/journal.ppat.1007537] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 02/08/2019] [Accepted: 12/18/2018] [Indexed: 02/05/2023] Open
Abstract
c-di-AMP is an important second messenger molecule that plays a pivotal role in regulating fundamental cellular processes, including osmotic and cell wall homeostasis in many Gram-positive organisms. In the opportunistic human pathogen Staphylococcus aureus, c-di-AMP is produced by the membrane-anchored DacA enzyme. Inactivation of this enzyme leads to a growth arrest under standard laboratory growth conditions and a re-sensitization of methicillin-resistant S. aureus (MRSA) strains to ß-lactam antibiotics. The gene coding for DacA is part of the conserved three-gene dacA/ybbR/glmM operon that also encodes the proposed DacA regulator YbbR and the essential phosphoglucosamine mutase GlmM, which is required for the production of glucosamine-1-phosphate, an early intermediate of peptidoglycan synthesis. These three proteins are thought to form a complex in vivo and, in this manner, help to fine-tune the cellular c-di-AMP levels. To further characterize this important regulatory complex, we conducted a comprehensive structural and functional analysis of the S. aureus DacA and GlmM enzymes by determining the structures of the S. aureus GlmM enzyme and the catalytic domain of DacA. Both proteins were found to be dimers in solution as well as in the crystal structures. Further site-directed mutagenesis, structural and enzymatic studies showed that multiple DacA dimers need to interact for enzymatic activity. We also show that DacA and GlmM form a stable complex in vitro and that S. aureus GlmM, but not Escherichia coli or Pseudomonas aeruginosa GlmM, acts as a strong inhibitor of DacA function without the requirement of any additional cellular factor. Based on Small Angle X-ray Scattering (SAXS) data, a model of the complex revealed that GlmM likely inhibits DacA by masking the active site of the cyclase and preventing higher oligomer formation. Together these results provide an important mechanistic insight into how c-di-AMP production can be regulated in the cell.
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Affiliation(s)
- Tommaso Tosi
- Section of Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
| | - Fumiya Hoshiga
- Section of Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
| | - Charlotte Millership
- Section of Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
| | - Rahul Singh
- Section of Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
| | - Charles Eldrid
- Institute of Structural and Molecular Biology, Birkbeck College, University of London, Malet Street, London, United Kingdom
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, London, United Kingdom
| | - Delphine Patin
- Institute for Integrative Biology of the Cell, CEA, CNRS, Univ Paris-Sud and Université Paris-Saclay, Gif-sur-Yvette, France
| | - Dominique Mengin-Lecreulx
- Institute for Integrative Biology of the Cell, CEA, CNRS, Univ Paris-Sud and Université Paris-Saclay, Gif-sur-Yvette, France
| | - Konstantinos Thalassinos
- Institute of Structural and Molecular Biology, Birkbeck College, University of London, Malet Street, London, United Kingdom
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, London, United Kingdom
| | - Paul Freemont
- Section of Structural Biology, Department of Medicine, Imperial College London, London, United Kingdom
| | - Angelika Gründling
- Section of Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
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El Khoury JY, Boucher N, Bergeron MG, Leprohon P, Ouellette M. Penicillin induces alterations in glutamine metabolism in Streptococcus pneumoniae. Sci Rep 2017; 7:14587. [PMID: 29109543 PMCID: PMC5673960 DOI: 10.1038/s41598-017-15035-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 10/19/2017] [Indexed: 11/09/2022] Open
Abstract
Penicillin is a bactericidal antibiotic that inhibits the synthesis of the peptidoglycan by targeting penicillin-binding proteins. This study aimed to assess through transcriptional profiling the stress response of S. pneumoniae strains after exposure to lethal penicillin concentrations to understand further the mode of action of penicillin. Two experimental designs (time-course and dose-response) were used for monitoring the effect of penicillin on the transcriptional profile. The expression of some genes previously shown to be modulated by penicillin was altered, including ciaRH, pstS and clpL. Genes of the glnRA and glnPQ operons were among the most downregulated genes in the three strains. These genes are involved in glutamine synthesis and uptake and LC-MS work confirmed that penicillin treatment increases the intracellular glutamine concentrations. Glutamine conferred a protective role against penicillin when added to the culture medium. Glutamine synthetase encoded by glnA catalyses the transformation of glutamate and ammonium into glutamine and its chemical inhibition by the inhibitor L-methionine sulfoximine is shown to sensitize S. pneumoniae to penicillin, including penicillin-resistant clinical isolates. In summary, a combination of RNA-seq and metabolomics revealed that penicillin interferes with glutamine metabolism suggesting strategies that could eventually be exploited for combination therapy or for reversal of resistance.
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Affiliation(s)
- Jessica Y El Khoury
- Centre de Recherche en Infectiologie du Centre de Recherche du CHU de Québec and Département de Microbiologie, Infectiologie et Immunologie, Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Nancy Boucher
- Centre de Recherche en Infectiologie du Centre de Recherche du CHU de Québec and Département de Microbiologie, Infectiologie et Immunologie, Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Michel G Bergeron
- Centre de Recherche en Infectiologie du Centre de Recherche du CHU de Québec and Département de Microbiologie, Infectiologie et Immunologie, Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Philippe Leprohon
- Centre de Recherche en Infectiologie du Centre de Recherche du CHU de Québec and Département de Microbiologie, Infectiologie et Immunologie, Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Marc Ouellette
- Centre de Recherche en Infectiologie du Centre de Recherche du CHU de Québec and Département de Microbiologie, Infectiologie et Immunologie, Faculté de Médecine, Université Laval, Québec, Québec, Canada.
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7
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Comparative transcriptional profiling of tildipirosin-resistant and sensitive Haemophilus parasuis. Sci Rep 2017; 7:7517. [PMID: 28790420 PMCID: PMC5548900 DOI: 10.1038/s41598-017-07972-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 07/03/2017] [Indexed: 11/09/2022] Open
Abstract
Numerous studies have been conducted to examine the molecular mechanism of Haemophilus parasuis resistance to antibiotic, but rarely to tildipirosin. In the current study, transcriptional profiling was applied to analyse the variation in gene expression of JS0135 and tildipirosin-resistant JS32. The growth curves showed that JS32 had a higher growth rate but fewer bacteria than JS0135. The cell membranes of JS32 and a resistant clinical isolate (HB32) were observed to be smoother than those of JS0135. From the comparative gene expression profile 349 up- and 113 downregulated genes were observed, covering 37 GO and 63 KEGG pathways which are involved in biological processes (11), cellular components (17), molecular function (9), cellular processes (1), environmental information processing (4), genetic information processing (9) and metabolism (49) affected in JS32. In addition, the relative overexpression of genes of the metabolism pathway (HAPS_RS09315, HAPS_RS09320), ribosomes (HAPS_RS07815) and ABC transporters (HAPS_RS10945) was detected, particularly the metabolism pathway, and verified with RT-qPCR. Collectively, the gene expression profile in connection with tildipirosin resistance factors revealed unique and highly resistant determinants of H. parasuis to macrolides that warrant further attention due to the significant threat of bacterial resistance.
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Bowman L, Zeden MS, Schuster CF, Kaever V, Gründling A. New Insights into the Cyclic Di-adenosine Monophosphate (c-di-AMP) Degradation Pathway and the Requirement of the Cyclic Dinucleotide for Acid Stress Resistance in Staphylococcus aureus. J Biol Chem 2016; 291:26970-26986. [PMID: 27834680 PMCID: PMC5207132 DOI: 10.1074/jbc.m116.747709] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 11/09/2016] [Indexed: 12/02/2022] Open
Abstract
Nucleotide signaling networks are key to facilitate alterations in gene expression, protein function, and enzyme activity in response to diverse stimuli. Cyclic di-adenosine monophosphate (c-di-AMP) is an important secondary messenger molecule produced by the human pathogen Staphylococcus aureus and is involved in regulating a number of physiological processes including potassium transport. S. aureus must ensure tight control over its cellular levels as both high levels of the dinucleotide and its absence result in a number of detrimental phenotypes. Here we show that in addition to the membrane-bound Asp-His-His and Asp-His-His-associated (DHH/DHHA1) domain-containing phosphodiesterase (PDE) GdpP, S. aureus produces a second cytoplasmic DHH/DHHA1 PDE Pde2. Although capable of hydrolyzing c-di-AMP, Pde2 preferentially converts linear 5'-phosphadenylyl-adenosine (pApA) to AMP. Using a pde2 mutant strain, pApA was detected for the first time in S. aureus, leading us to speculate that this dinucleotide may have a regulatory role under certain conditions. Moreover, pApA is involved in a feedback inhibition loop that limits GdpP-dependent c-di-AMP hydrolysis. Another protein linked to the regulation of c-di-AMP levels in bacteria is the predicted regulator protein YbbR. Here, it is shown that a ybbR mutant S. aureus strain has increased acid sensitivity that can be bypassed by the acquisition of mutations in a number of genes, including the gene coding for the diadenylate cyclase DacA. We further show that c-di-AMP levels are slightly elevated in the ybbR suppressor strains tested as compared with the wild-type strain. With this, we not only identified a new role for YbbR in acid stress resistance in S. aureus but also provide further insight into how c-di-AMP levels impact acid tolerance in this organism.
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Affiliation(s)
- Lisa Bowman
- From the Section of Microbiology and Medical Research Council Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, United Kingdom and
| | - Merve S Zeden
- From the Section of Microbiology and Medical Research Council Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, United Kingdom and
| | - Christopher F Schuster
- From the Section of Microbiology and Medical Research Council Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, United Kingdom and
| | - Volkhard Kaever
- the Research Core Unit Metabolomics, Hannover Medical School, Hannover D-306625, Germany
| | - Angelika Gründling
- From the Section of Microbiology and Medical Research Council Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, United Kingdom and
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Moraes GL, Gomes GC, Monteiro de Sousa PR, Alves CN, Govender T, Kruger HG, Maguire GEM, Lamichhane G, Lameira J. Structural and functional features of enzymes of Mycobacterium tuberculosis peptidoglycan biosynthesis as targets for drug development. Tuberculosis (Edinb) 2015; 95:95-111. [PMID: 25701501 DOI: 10.1016/j.tube.2015.01.006] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 01/13/2015] [Accepted: 01/19/2015] [Indexed: 10/24/2022]
Abstract
Tuberculosis (TB) is the second leading cause of human mortality from infectious diseases worldwide. The WHO reported 1.3 million deaths and 8.6 million new cases of TB in 2012. Mycobacterium tuberculosis (M. tuberculosis), the infectious bacteria that causes TB, is encapsulated by a thick and robust cell wall. The innermost segment of the cell wall is comprised of peptidoglycan, a layer that is required for survival and growth of the pathogen. Enzymes that catalyse biosynthesis of the peptidoglycan are essential and are therefore attractive targets for discovery of novel antibiotics as humans lack similar enzymes making it possible to selectively target bacteria only. In this paper, we have reviewed the structures and functions of enzymes GlmS, GlmM, GlmU, MurA, MurB, MurC, MurD, MurE and MurF from M. tuberculosis that are involved in peptidoglycan biosynthesis. In addition, we report homology modelled 3D structures of those key enzymes from M. tuberculosis of which the structures are still unknown. We demonstrated that natural substrates can be successfully docked into the active sites of the GlmS and GlmU respectively. It is therefore expected that the models and the data provided herein will facilitate translational research to develop new drugs to treat TB.
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Affiliation(s)
- Gleiciane Leal Moraes
- Laboratório de Planejamento de Fármacos, Instituto de Ciências Exatas e Naturais, Universidade Federal do Pará, CEP 66075-110 Belém, PA, Brazil
| | - Guelber Cardoso Gomes
- Laboratório de Planejamento de Fármacos, Instituto de Ciências Exatas e Naturais, Universidade Federal do Pará, CEP 66075-110 Belém, PA, Brazil; Instituto de Ciências Biológicas, Universidade Federal do Pará, CEP 66075-110 Belém, PA, Brazil
| | - Paulo Robson Monteiro de Sousa
- Laboratório de Planejamento de Fármacos, Instituto de Ciências Exatas e Naturais, Universidade Federal do Pará, CEP 66075-110 Belém, PA, Brazil
| | - Cláudio Nahum Alves
- Laboratório de Planejamento de Fármacos, Instituto de Ciências Exatas e Naturais, Universidade Federal do Pará, CEP 66075-110 Belém, PA, Brazil
| | - Thavendran Govender
- Catalysis and Peptide Research Unit, School of Health Sciences, University of KwaZulu-Natal, South Africa
| | - Hendrik G Kruger
- Catalysis and Peptide Research Unit, School of Health Sciences, University of KwaZulu-Natal, South Africa
| | - Glenn E M Maguire
- Catalysis and Peptide Research Unit, School of Health Sciences, University of KwaZulu-Natal, South Africa
| | - Gyanu Lamichhane
- Johns Hopkins University School of Medicine, Taskforce to Study Resistance Emergence & Antimicrobial Development Technology, 1503 E. Jefferson St, Baltimore, MD 21231, USA
| | - Jerônimo Lameira
- Laboratório de Planejamento de Fármacos, Instituto de Ciências Exatas e Naturais, Universidade Federal do Pará, CEP 66075-110 Belém, PA, Brazil; Instituto de Ciências Biológicas, Universidade Federal do Pará, CEP 66075-110 Belém, PA, Brazil.
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10
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Dengler V, McCallum N, Kiefer P, Christen P, Patrignani A, Vorholt JA, Berger-Bächi B, Senn MM. Mutation in the C-di-AMP cyclase dacA affects fitness and resistance of methicillin resistant Staphylococcus aureus. PLoS One 2013; 8:e73512. [PMID: 24013956 PMCID: PMC3754961 DOI: 10.1371/journal.pone.0073512] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 07/22/2013] [Indexed: 01/28/2023] Open
Abstract
Faster growing and more virulent strains of methicillin resistant Staphylococcus aureus (MRSA) are increasingly displacing highly resistant MRSA. Elevated fitness in these MRSA is often accompanied by decreased and heterogeneous levels of methicillin resistance; however, the mechanisms for this phenomenon are not yet fully understood. Whole genome sequencing was used to investigate the genetic basis of this apparent correlation, in an isogenic MRSA strain pair that differed in methicillin resistance levels and fitness, with respect to growth rate. Sequencing revealed only one single nucleotide polymorphism (SNP) in the diadenylate cyclase gene dacA in the faster growing but less resistant strain. Diadenylate cyclases were recently discovered to synthesize the new second messenger cyclic diadenosine monophosphate (c-di-AMP). Introduction of this mutation into the highly resistant but slower growing strain reduced resistance and increased its growth rate, suggesting a direct connection between the dacA mutation and the phenotypic differences of these strains. Quantification of cellular c-di-AMP revealed that the dacA mutation decreased c-di-AMP levels resulting in reduced autolysis, increased salt tolerance and a reduction in the basal expression of the cell wall stress stimulon. These results indicate that c-di-AMP affects cell envelope-related signalling in S. aureus. The influence of c-di-AMP on growth rate and methicillin resistance in MRSA indicate that altering c-di-AMP levels could be a mechanism by which MRSA strains can increase their fitness levels by reducing their methicillin resistance levels.
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Affiliation(s)
- Vanina Dengler
- Institute of Medical Microbiology, University of Zurich, Zurich, Switzerland
| | - Nadine McCallum
- Institute of Medical Microbiology, University of Zurich, Zurich, Switzerland
- Sydney Emerging Infectious Diseases and Biosecurity Institute (SEIB), University of Sydney, Sydney, Australia
| | - Patrick Kiefer
- Institute of Microbiology, ETH Zurich, Zurich, Switzerland
| | | | - Andrea Patrignani
- Functional Genomics Center Zurich, University/ETH Zurich, Zurich, Switzerland
| | | | | | - Maria M. Senn
- Institute of Medical Microbiology, University of Zurich, Zurich, Switzerland
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11
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Monteiro R, Vitorino R, Domingues P, Radhouani H, Carvalho C, Poeta P, Torres C, Igrejas G. Proteome of a methicillin-resistant Staphylococcus aureus clinical strain of sequence type ST398. J Proteomics 2012; 75:2892-915. [PMID: 22245554 DOI: 10.1016/j.jprot.2011.12.036] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Revised: 12/20/2011] [Accepted: 12/22/2011] [Indexed: 10/14/2022]
Abstract
Proteomics is a powerful tool to analyze the differences in gene expression of bacterial strains. Staphylococcus aureus has long been recognized as an important pathogen in human disease. In order to investigate this pathogen, the proteome of a clinical methicillin-resistant S. aureus (MRSA) strain of the sequence type ST398 was determined using 2-DE. Using 2-DE we obtained a total of 105 spots the MRSA strain. Furthermore in correlation with bioinformatic databases, they allowed accurate identification and characterization of proteins, resulting in 227 identified proteins. There were found proteins related to basic function of the cell, but also proteins related to virulence like catalase, specific of S. aureus species, and proteins related to antibiotic resistance. Proteins associated with antibiotic resistance or virulence factors are related to genomic databases. The most abundant classes identified involved glycolysis, energy production, one-carbon metabolism, and oxidation-reduction process, all of which reflect an active metabolism. These results highlight the importance of proteomics to deepen in the knowledge of protein expression of MRSA strain of the lineage ST398, microorganism with diverse and important resistance mechanisms. With this proteome map we have an essential tool for a better understanding of this pathogen and providing new data for protein databases. This article is part of a Special Issue entitled: Proteomics: The clinical link.
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Affiliation(s)
- R Monteiro
- Department of Genetics and Biotechnology, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal
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12
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Frees D, Andersen JH, Hemmingsen L, Koskenniemi K, Bæk KT, Muhammed MK, Gudeta DD, Nyman TA, Sukura A, Varmanen P, Savijoki K. New Insights into Staphylococcus aureus Stress Tolerance and Virulence Regulation from an Analysis of the Role of the ClpP Protease in the Strains Newman, COL, and SA564. J Proteome Res 2011; 11:95-108. [DOI: 10.1021/pr200956s] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Dorte Frees
- Department of Veterinary Disease Biology, Faculty of Life Sciences, University of Copenhagen, Stigbøjlen 4 DK-1870, Frederiksberg C, Denmark
| | - Julie Hove Andersen
- Department of Veterinary Disease Biology, Faculty of Life Sciences, University of Copenhagen, Stigbøjlen 4 DK-1870, Frederiksberg C, Denmark
| | - Lene Hemmingsen
- Department of Veterinary Disease Biology, Faculty of Life Sciences, University of Copenhagen, Stigbøjlen 4 DK-1870, Frederiksberg C, Denmark
- Department of Veterinary Biosciences, University of Helsinki, Finland
| | | | - Kristoffer T. Bæk
- Department of Veterinary Disease Biology, Faculty of Life Sciences, University of Copenhagen, Stigbøjlen 4 DK-1870, Frederiksberg C, Denmark
| | - Musemma Kedir Muhammed
- Department of Veterinary Disease Biology, Faculty of Life Sciences, University of Copenhagen, Stigbøjlen 4 DK-1870, Frederiksberg C, Denmark
| | - Dereje Dadi Gudeta
- Department of Veterinary Disease Biology, Faculty of Life Sciences, University of Copenhagen, Stigbøjlen 4 DK-1870, Frederiksberg C, Denmark
| | - Tuula A. Nyman
- Institute of Biotechnology, University of Helsinki, Finland
| | - Antti Sukura
- Department of Veterinary Biosciences, University of Helsinki, Finland
| | - Pekka Varmanen
- Department of Food and Environmental Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Finland
| | - Kirsi Savijoki
- Institute of Biotechnology, University of Helsinki, Finland
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13
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Barb AW, Cort JR, Seetharaman J, Lew S, Lee HW, Acton T, Xiao R, Kennedy MA, Tong L, Montelione GT, Prestegard JH. Structures of domains I and IV from YbbR are representative of a widely distributed protein family. Protein Sci 2011; 20:396-405. [PMID: 21154411 DOI: 10.1002/pro.571] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Revised: 11/19/2010] [Accepted: 11/19/2010] [Indexed: 01/27/2023]
Abstract
YbbR domains are widespread throughout Eubacteria and are expressed as monomeric units, linked in tandem repeats or cotranslated with other domains. Although the precise role of these domains remains undefined, the location of the multiple YbbR domain-encoding ybbR gene in the Bacillus subtilis glmM operon and its previous identification as a substrate for a surfactin-type phosphopantetheinyl transferase suggests a role in cell growth, division, and virulence. To further characterize the YbbR domains, structures of two of the four domains (I and IV) from the YbbR-like protein of Desulfitobacterium hafniense Y51 were solved by solution nuclear magnetic resonance and X-ray crystallography. The structures show the domains to have nearly identical topologies despite a low amino acid identity (23%). The topology is dominated by β-strands, roughly following a "figure 8" pattern with some strands coiling around the domain perimeter and others crossing the center. A similar topology is found in the C-terminal domain of two stress-responsive bacterial ribosomal proteins, TL5 and L25. Based on these models, a structurally guided amino acid alignment identifies features of the YbbR domains that are not evident from naïve amino acid sequence alignments. A structurally conserved cis-proline (cis-Pro) residue was identified in both domains, though the local structure in the immediate vicinities surrounding this residue differed between the two models. The conservation and location of this cis-Pro, plus anchoring Val residues, suggest this motif may be significant to protein function.
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Affiliation(s)
- Adam W Barb
- Complex Carbohydrate Research Center, The University of Georgia, Athens, Georgia, USA
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14
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Li G, Che D, Xu Y. A universal operon predictor for prokaryotic genomes. J Bioinform Comput Biol 2009; 7:19-38. [PMID: 19226658 DOI: 10.1142/s0219720009003984] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2007] [Revised: 02/21/2008] [Accepted: 04/22/2008] [Indexed: 11/18/2022]
Abstract
Identification of operons at the genome scale of prokaryotic organisms represents a key step in deciphering of their transcriptional regulation machinery, biological pathways, and networks. While numerous computational methods have been shown to be effective in predicting operons for well-studied organisms such as Escherichia coli K12 and Bacillus subtilis 168, these methods generally do not generalize well to genomes other than the ones used to train the methods, or closely related genomes because they rely on organism-specific information. Several methods have been explored to address this problem through utilizing only genomic structural information conserved across multiple organisms, but they all suffer from the issue of low prediction sensitivity. In this paper, we report a novel operon prediction method that is applicable to any prokaryotic genome with high prediction accuracy. The key idea of the method is to predict operons through identification of conserved gene clusters across multiple genomes and through deriving a key parameter relevant to the distribution of intergenic distances in genomes. We have implemented this method using a graph-theoretic approach, to calculate a set of maximum gene clusters in the target genome that are conserved across multiple reference genomes. Our computational results have shown that this method has higher prediction sensitivity as well as specificity than most of the published methods. We have carried out a preliminary study on operons unique to archaea and bacteria, respectively, and derived a number of interesting new insights about operons between these two kingdoms. The software and predicted operons of 365 prokaryotic genomes are available at http://csbl.bmb.uga.edu/~dongsheng/UNIPOP.
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Affiliation(s)
- Guojun Li
- CSBL, Department of Biochemistry and Molecular Biology, Department of Computer Science, University of Georgia, Athens, GA 30602, USA.
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15
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Shimazu K, Takahashi Y, Uchikawa Y, Shimazu Y, Yajima A, Takashima E, Aoba T, Konishi K. Identification of the Streptococcus gordonii glmM gene encoding phosphoglucosamine mutase and its role in bacterial cell morphology, biofilm formation, and sensitivity to antibiotics. ACTA ACUST UNITED AC 2008; 53:166-77. [PMID: 18462386 DOI: 10.1111/j.1574-695x.2008.00410.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Phosphoglucosamine mutase (EC 5.4.2.10) catalyzes the interconversion of glucosamine-6-phosphate into glucosamine-1-phosphate, an essential step in the biosynthetic pathway leading to the formation of peptidoglycan precursor uridine 5'-diphospho-N-acetylglucosamine. The gene (glmM) of Escherichia coli encoding the enzyme has been identified previously. We have now identified a glmM homolog in Streptococcus gordonii, an early colonizer on the human tooth and an important cause of infective endocarditis, and have confirmed that the gene encodes phosphoglucosamine mutase by assaying the enzymatic activity of the recombinant GlmM protein. Insertional glmM mutant of S. gordonii did not produce GlmM, and had a growth rate that was approximately half that of the wild type. Morphological analyses clearly indicated that the glmM mutation causes marked elongation of the streptococcal chains, enlargement of bacterial cells, and increased roughness of the bacterial cell surface. Furthermore, the glmM mutation reduces biofilm formation and increases sensitivity to penicillins relative to wild type. All of these phenotypic changes were also observed in a glmM deletion mutant, and were restored by the complementation with plasmid-borne glmM. These results suggest that, in S. gordonii, mutations in glmM appear to influence bacterial cell growth and morphology, biofilm formation, and sensitivity to penicillins.
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Affiliation(s)
- Kisaki Shimazu
- Department of Pediatric Dentistry, Nippon Dental University School of Life Dentistry at Tokyo, Tokyo, Japan
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16
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Barreteau H, Kovac A, Boniface A, Sova M, Gobec S, Blanot D. Cytoplasmic steps of peptidoglycan biosynthesis. FEMS Microbiol Rev 2008; 32:168-207. [PMID: 18266853 DOI: 10.1111/j.1574-6976.2008.00104.x] [Citation(s) in RCA: 479] [Impact Index Per Article: 29.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
The biosynthesis of bacterial cell wall peptidoglycan is a complex process that involves enzyme reactions that take place in the cytoplasm (synthesis of the nucleotide precursors) and on the inner side (synthesis of lipid-linked intermediates) and outer side (polymerization reactions) of the cytoplasmic membrane. This review deals with the cytoplasmic steps of peptidoglycan biosynthesis, which can be divided into four sets of reactions that lead to the syntheses of (1) UDP-N-acetylglucosamine from fructose 6-phosphate, (2) UDP-N-acetylmuramic acid from UDP-N-acetylglucosamine, (3) UDP-N-acetylmuramyl-pentapeptide from UDP-N-acetylmuramic acid and (4) D-glutamic acid and dipeptide D-alanyl-D-alanine. Recent data concerning the different enzymes involved are presented. Moreover, special attention is given to (1) the chemical and enzymatic synthesis of the nucleotide precursor substrates that are not commercially available and (2) the search for specific inhibitors that could act as antibacterial compounds.
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Affiliation(s)
- Hélène Barreteau
- Laboratoire des Enveloppes Bactériennes et Antibiotiques, Institut de Biochimie et Biophysique Moléculaire et Cellulaire, Univ Paris-Sud, Orsay, France
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17
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Hübscher J, Jansen A, Kotte O, Schäfer J, Majcherczyk PA, Harris LG, Bierbaum G, Heinemann M, Berger-Bächi B. Living with an imperfect cell wall: compensation of femAB inactivation in Staphylococcus aureus. BMC Genomics 2007; 8:307. [PMID: 17784943 PMCID: PMC2045680 DOI: 10.1186/1471-2164-8-307] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2007] [Accepted: 09/04/2007] [Indexed: 12/17/2022] Open
Abstract
Background Synthesis of the Staphylococcus aureus peptidoglycan pentaglycine interpeptide bridge is catalyzed by the nonribosomal peptidyl transferases FemX, FemA and FemB. Inactivation of the femAB operon reduces the interpeptide to a monoglycine, leading to a poorly crosslinked peptidoglycan. femAB mutants show a reduced growth rate and are hypersusceptible to virtually all antibiotics, including methicillin, making FemAB a potential target to restore β-lactam susceptibility in methicillin-resistant S. aureus (MRSA). Cis-complementation with wild type femAB only restores synthesis of the pentaglycine interpeptide and methicillin resistance, but the growth rate remains low. This study characterizes the adaptations that ensured survival of the cells after femAB inactivation. Results In addition to slow growth, the cis-complemented femAB mutant showed temperature sensitivity and a higher methicillin resistance than the wild type. Transcriptional profiling paired with reporter metabolite analysis revealed multiple changes in the global transcriptome. A number of transporters for sugars, glycerol, and glycine betaine, some of which could serve as osmoprotectants, were upregulated. Striking differences were found in the transcription of several genes involved in nitrogen metabolism and the arginine-deiminase pathway, an alternative for ATP production. In addition, microarray data indicated enhanced expression of virulence factors that correlated with premature expression of the global regulators sae, sarA, and agr. Conclusion Survival under conditions preventing normal cell wall formation triggered complex adaptations that incurred a fitness cost, showing the remarkable flexibility of S. aureus to circumvent cell wall damage. Potential FemAB inhibitors would have to be used in combination with other antibiotics to prevent selection of resistant survivors.
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Affiliation(s)
- Judith Hübscher
- Institute of Medical Microbiology, University of Zürich, Zürich, Switzerland
| | - Andrea Jansen
- Institute for Medical Microbiology, Immunology and Parasitology, University of Bonn, Bonn, Germany
| | - Oliver Kotte
- Institute of Molecular Systems Biology, ETH Zürich, Zürich, Switzerland
| | | | - Paul A Majcherczyk
- Division of Infectious Diseases, Department of Internal Medicine, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Llinos G Harris
- AO Research Institute, Davos, Switzerland
- School of Medicine, University of Wales Swansea, Swansea, UK
| | - Gabriele Bierbaum
- Institute for Medical Microbiology, Immunology and Parasitology, University of Bonn, Bonn, Germany
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18
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McCallum N, Brassinga AKC, Sifri CD, Berger-Bächi B. Functional characterization of TcaA: minimal requirement for teicoplanin susceptibility and role in Caenorhabditis elegans virulence. Antimicrob Agents Chemother 2007; 51:3836-43. [PMID: 17709474 PMCID: PMC2151418 DOI: 10.1128/aac.00722-07] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The inactivation of TcaA contributes to intrinsic teicoplanin resistance in experimental and clinical isolates of glycopeptide-intermediate resistant Staphylococcus aureus. PhoA fusions confirmed that TcaA is a transmembrane protein with a short intracellular N-terminal domain containing a C-4 zinc finger binding motif, a single membrane-spanning domain, and a large extracellular C-terminal domain. The region conferring teicoplanin susceptibility was narrowed down to the transmembrane part and the first third of the extracellular domain of TcaA, suggesting that neither the C-4 zinc finger binding motif nor the C terminus contributed to teicoplanin susceptibility. TcaA belongs to the cell wall stress stimulon, which comprises a set of genes universally upregulated by cell wall damage. Induction of tcaA was shown to be fully dependent on the two-component regulatory system VraSR. A 66-bp region upstream of the transcriptional start site, which contained an inverted repeat partially covering the promoter box, was shown to be essential for VraSR-mediated induction by cell wall stress. Interestingly, the induction or overexpression of tcaA did not contribute further to teicoplanin susceptibility, suggesting that small amounts of TcaA, such as those present under normal uninduced conditions, were sufficient for TcaA-mediated teicoplanin susceptibility. The strong attenuation of tcaA deletion mutants in a Caenorhabditis elegans survival assay suggested that TcaA may, in addition to affecting glycopeptide susceptibility, also play a role in virulence.
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Affiliation(s)
- Nadine McCallum
- Institute of Medical Microbiology, University of Zurich, Gloriastr. 32, 8006 Zurich, Switzerland.
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19
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Komatsuzawa H, Fujiwara T, Nishi H, Yamada S, Ohara M, McCallum N, Berger-Bächi B, Sugai M. The gate controlling cell wall synthesis in Staphylococcus aureus. Mol Microbiol 2004; 53:1221-31. [PMID: 15306023 DOI: 10.1111/j.1365-2958.2004.04200.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Glucosamine-6-P occupies a central position between cell wall synthesis and glycolysis. In the initial steps leading to peptidoglycan precursor formation glucosamine-6-P is processed sequentially to UDP-N-acetylglucosamine, while to enter the glycolysis pathway, glucosamine-6-P is isomerized by NagB to fructose-6-P. Although we could not demonstrate NagB activity, nagB inactivation significantly reduced growth. Mutational analysis showed that NagA was involved in glucosamine-6-P formation from N-acetylglucosamine-6-P, and GlmS in that from fructose-6-P. Inactivation of glmS prevented growth on glucose as sole carbon source, which resumed after complementation with N-acetylglucosamine. Transcription of glmS as well as the amount of GlmS was reduced in the presence of N-acetylglucosamine. This and the preferential incorporation of N-acetylglucosamine over glucose into cell wall material showed that N-acetylglucosamine was used exclusively for cell wall synthesis, while glucose served both cell wall synthesis and glycolysis. These observations suggest furthermore GlmS to be the key and only enzyme leading from glucose to cell wall synthesis in Staphylococcus aureus, and show that there exists a tight regulation and hierarchy in sugar utilization. Inactivation of nagA, nagB or glmS affected the susceptibility of S. aureus to cell wall synthesis inhibitors, suggesting an interdependence between efficiency of cell wall precursor formation and resistance levels.
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Affiliation(s)
- Hitoshi Komatsuzawa
- Department of Bacteriology, Hiroshima University Graduate School of Biomedical Sciences, Kasumi 1-2-3, Minami-ku, Hiroshima city, Hiroshima 734-8553, Japan.
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20
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Wang L, Trawick JD, Yamamoto R, Zamudio C. Genome-wide operon prediction in Staphylococcus aureus. Nucleic Acids Res 2004; 32:3689-702. [PMID: 15252153 PMCID: PMC484181 DOI: 10.1093/nar/gkh694] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2004] [Revised: 06/07/2004] [Accepted: 06/21/2004] [Indexed: 01/10/2023] Open
Abstract
Identification of operon structure is critical to understanding gene regulation and function, and pathogenesis, and for identifying targets towards the development of new antibiotics in bacteria. Recently, the complete genome sequences of a large number of important human bacterial pathogens have become available for computational analysis, including the major human Gram-positive pathogen Staphylococcus aureus. By annotating the predicted operon structure of the S.aureus genome, we hope to facilitate the exploration of the unique biology of this organism as well as the comparative genomics across a broad range of bacteria. We have integrated several operon prediction methods and developed a consensus approach to score the likelihood of each adjacent gene pair to be co-transcribed. Gene pairs were separated into distinct operons when scores were equal to or below an empirical threshold. Using this approach, we have generated a S.aureus genome map with scores annotated at the intersections of every adjacent gene pair. This approach predicted about 864 monocistronic transcripts and 533 polycistronic operons from the protein-encoding genes in the S.aureus strain Mu50 genome. When compared with a set of experimentally determined S.aureus operons from literature sources, this method successfully predicted at least 91% of gene pairs. At the transcription unit level, this approach correctly identified at least 92% of complete operons in this dataset. This consensus approach has enabled us to predict operons with high accuracy from a genome where limited experimental evidence for operon structure is available.
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Affiliation(s)
- Liangsu Wang
- Elitra Pharmaceuticals Inc., 10410 Science Center Drive, San Diego, CA 92121, USA.
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21
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Cordwell SJ, Larsen MR, Cole RT, Walsh BJ. Comparative proteomics of Staphylococcus aureus and the response of methicillin-resistant and methicillin-sensitive strains to Triton X-100. MICROBIOLOGY (READING, ENGLAND) 2002; 148:2765-2781. [PMID: 12213923 DOI: 10.1099/00221287-148-9-2765] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Proteomics is a powerful tool for analysing differences in gene expression between bacterial strains with alternate phenotypes. Staphylococcus aureus strains are grouped on the basis of their sensitivity to methicillin. Two-dimensional gel electrophoresis was combined with MS to compare the protein profiles of S. aureus strains COL (methicillin-resistant) and 8325 (methicillin-sensitive). Reference mapping via this approach identified 377 proteins that corresponded to 266 distinct ORFs. Amongst these identified proteins were 14 potential virulence factors. The production of 41 'hypothetical' proteins was confirmed, and eight of these appeared to be unique to S. aureus. Strain COL displayed 12 protein spots, which included alkaline-shock protein 23 (Asp23) and cold-shock proteins CspABC, which either were not present in strain 8325 or were present at a significantly lower intensity in this strain. Comparative maps were used to characterize the S. aureus response to treatment with Triton X-100 (TX-100), a detergent that has been shown to reduce methicillin resistance independently of an interaction with the mecA-encoded penicillin-binding protein 2a. In response to growth of the bacteria in the presence of TX-100, 44 protein spots showed altered levels of abundance, and 11 of these spots were found only in COL. The products of genes regulated by sigma(B) (the alternative sigma factor), including Asp23 and three proteins of unknown function, and SarA (a regulator of virulence genes) were shown to be present at significantly altered levels. SarA production was induced in TX-100-treated cultures. A protein of the sigma(B) operon, RsbV, was only detected in COL and its production was down-regulated in COL when the strain was treated with TX-100, whereas RsbW was present at reduced levels in both strains. Upon growth of both strains in the presence of TX-100, no effects on the production of the essential methicillin-resistance factor FemA were detected, whereas phosphoglucosamine mutase (GlmM) production was reduced in COL alone. This study suggests that proteins of the sigma(B) and sarA regulons, as well as other factors, are involved in methicillin resistance in S. aureus.
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Affiliation(s)
- Stuart J Cordwell
- Australian Proteome Analysis Facility, Level 4, Building F7B, Macquarie University, Sydney, Australia21091
| | - Martin R Larsen
- Australian Proteome Analysis Facility, Level 4, Building F7B, Macquarie University, Sydney, Australia21091
| | - Rebecca T Cole
- Australian Proteome Analysis Facility, Level 4, Building F7B, Macquarie University, Sydney, Australia21091
| | - Bradley J Walsh
- Australian Proteome Analysis Facility, Level 4, Building F7B, Macquarie University, Sydney, Australia21091
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22
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Komatsuzawa H, Ohta K, Sugai M, Fujiwara T, Glanzmann P, Suginaka H. Tn551-mediated insertional inactivation of the fmtB gene encoding a cell wall-associated protein abolishes methicillin resistance in Staphylococcus aureus. J Antimicrob Chemother 2000; 45:421-31. [PMID: 10896508 DOI: 10.1093/jac/45.4.421] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A Tn551 insert in a gene termed fmtB was shown to reduce oxacillin as well as Triton X-100 resistance in highly methicillin-resistant Staphylococcus aureus (MRSA) COL. Backcrosses of fmtB::Tn551 into S. aureus COL and into two genetically distinct MRSA strains, KSA8 and NCTC10443, confirmed the linkage of fmtB::Tn551 with loss of oxacillin resistance. The fmtB gene codes for a protein of a deduced molecular mass of 263 kDa that contains 17 tandem repeats of 75 amino acids and a C-terminal LPXTG cell wall-sorting motif. Immunoblots with anti-FmtB antibodies confirmed its localization in the cell wall fraction. The fmtB gene was mapped downstream of the phosphoglucosamine mutase operon glmM which catalyses formation of glucosamine-1-phosphate. Oxacillin resistance was not restored in fmtB mutants by trans-complementation with fmtB. However, although GlmM production was not affected by fmtB inactivation, oxacillin resistance was increased in fmtB mutants by introducing a plasmid-borne glmM gene, presumably by GlmM overexpression. Interestingly, a similar phenotypic complementation was obtained in fmtB mutants by including substrate level concentrations of N-acetylglucosamine or glucosamine in the growth medium. Inactivation of the fmtB gene seems therefore to have an indirect effect on methicillin resistance which can be relieved by increasing the production of the cell wall precursor glucosamine-1-phosphate.
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Affiliation(s)
- H Komatsuzawa
- Department of Microbiology, Hiroshima University School of Dentistry, Japan.
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