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Liu Q, Chen Y, Xu XW. Genomic insight into strategy, interaction and evolution of nitrifiers in metabolizing key labile-dissolved organic nitrogen in different environmental niches. Front Microbiol 2023; 14:1273211. [PMID: 38156017 PMCID: PMC10753782 DOI: 10.3389/fmicb.2023.1273211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Accepted: 11/09/2023] [Indexed: 12/30/2023] Open
Abstract
Ammonia-oxidizing archaea (AOA) and bacteria (AOB), nitrite-oxidizing bacteria (NOB), and complete ammonia oxidizers (comammox) are responsible for nitrification in nature; however, some groups have been reported to utilize labile-dissolved organic nitrogen (LDON) for satisfying nitrogen demands. To understand the universality of their capacity of LDON metabolism, we collected 70 complete genomes of AOA, AOB, NOB, and comammox from typical environments for exploring their potentials in the metabolism of representative LDON (urea, polyamines, cyanate, taurine, glycine betaine, and methylamine). Genomic analyses showed that urea was the most popular LDON used by nitrifiers. Each group harbored unique urea transporter genes (AOA: dur3 and utp, AOB: utp, and NOB and comammox: urtABCDE and utp) accompanied by urease genes ureABC. The differentiation in the substrate affinity of these transporters implied the divergence of urea utilization efficiency in nitrifiers, potentially driving them into different niches. The cyanate transporter (cynABD and focA/nirC) and degradation (cynS) genes were detected mostly in NOB, indicating their preference for a wide range of nitrogen substrates to satisfy high nitrogen demands. The lack of genes involved in the metabolism of polyamines, taurine, glycine betaine, and methylamines in most of nitrifiers suggested that they were not able to serve as a source of ammonium, only if they were degraded or oxidized extracellularly as previously reported. The phylogenetic analyses assisted with comparisons of GC% and the Codon Adaptation Index between target genes and whole genomes of nitrifiers implied that urea metabolic genes dur3 and ureC in AOA evolved independently from bacteria during the transition from Thaumarchaeota to AOA, while utp in terrestrial AOA was acquired from bacteria via lateral gene transfer (LGT). Cyanate transporter genes cynS and focA/nirC detected only in a terrestrial AOA Candidadus Nitrsosphaera gargensis Ga9.2 could be gained synchronously with Nitrospira of NOB by an ancient LGT. Our results indicated that LDON utilization was a common feature in nitrifiers, but metabolic potentials were different among nitrifiers, possibly being intensely interacted with their niches, survival strategies, and evolutions.
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Affiliation(s)
- Qian Liu
- Donghai Laboratory, Zhoushan, Zhejiang, China
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, Zhejiang, China
- Ocean College, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yuhao Chen
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, Zhejiang, China
- School of Oceanography, Shanghai Jiao Tong University, Shanghai, China
| | - Xue-Wei Xu
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, Zhejiang, China
- Ocean College, Zhejiang University, Hangzhou, Zhejiang, China
- School of Oceanography, Shanghai Jiao Tong University, Shanghai, China
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2
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Proline transporters ProT and PutP are required for Staphylococcus aureus infection. PLoS Pathog 2023; 19:e1011098. [PMID: 36652494 PMCID: PMC9886301 DOI: 10.1371/journal.ppat.1011098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 01/30/2023] [Accepted: 01/03/2023] [Indexed: 01/19/2023] Open
Abstract
Proline acquired via specific transporters can serve as a proteinogenic substrate, carbon and nitrogen source, or osmolyte. Previous reports have documented that Staphylococcus aureus, a major community and nosocomial pathogen, encodes at least four proline transporters, PutP, OpuC, OpuD, and ProP. A combination of genetic approaches and 3H-proline transport assays reveal that a previously unrecognized transporter, ProT, in addition to PutP, are the major proline transporters in S. aureus. Complementation experiments using constitutively expressed non-cognate promoters found that proline transport via OpuD, OpuC, and ProP is minimal. Both proline biosynthesis from arginine and proline transport via ProT are critical for growth when S. aureus is grown under conditions of high salinity. Further, proline transport mediated by ProT or PutP are required for growth in media with and without glucose, indicating both transporters function to acquire proline for proteinogenic purposes in addition to acquisition of proline as a carbon/nitrogen source. Lastly, inactivation of proT and putP resulted in a significant reduction (5 log10) of bacterial burden in murine skin-and-soft tissue infection and bacteremia models, suggesting that proline transport is required to establish a S. aureus infection.
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3
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Proline Transport and Growth Changes in Proline Transport Mutants of Staphylococcus aureus. Microorganisms 2022; 10:microorganisms10101888. [DOI: 10.3390/microorganisms10101888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 09/19/2022] [Accepted: 09/21/2022] [Indexed: 11/16/2022] Open
Abstract
Staphylococcus aureus is a major cause of skin/soft tissue infections and more serious infections in humans. The species usually requires the importation of proline to be able to survive. Previous work has shown that single mutations in genes that encode for proline transporters affect the ability of S. aureus to survive in vitro and in vivo. To better understand proline transport in S. aureus, double and triple gene mutant strains were created that targeted the opuD, proP, and putP genes. Single gene mutants had some effect on proline transport, whereas double mutants exhibited significantly lower proline transport. An opuD prop putP triple gene mutant displayed the lowest proline transport under low- and high-affinity conditions. To assess growth differences caused by the mutations, the same mutants were grown in brain heart infusion (BHI) broth and defined staphylococcal medium (DSM) with various concentrations of proline. The triple mutant did not grow in DSM with a low concentration of proline and grew poorly in both DSM with a high proline concentration and BHI broth. These results show that S. aureus has multiple mechanisms to import proline into the cell and knocking out three of the main proline transporters significantly hinders S. aureus growth.
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4
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Nedashkovkaya OI, Kim SG, Balabanova LA, Zhukova NV, Son OM, Tekutyeva LA, Mikhailov VV. Genome-Based Classification of Strain 16-SW-7, a Marine Bacterium Capable of Converting B Red Blood Cells, as Pseudoalteromonas distincta and Proposal to Reclassify Pseudoalteromonas paragorgicola as a Later Heterotypic Synonym of Pseudoalteromonas distincta. Front Microbiol 2022; 12:809431. [PMID: 35222308 PMCID: PMC8865838 DOI: 10.3389/fmicb.2021.809431] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 12/23/2021] [Indexed: 11/13/2022] Open
Abstract
A strictly aerobic, Gram-stain-negative, rod-shaped, and motile bacterium, designated strain 16-SW-7, isolated from a seawater sample, was investigated in detail due to its ability to produce a unique α-galactosidase converting B red blood cells into the universal type blood cells. The phylogenetic analysis based on 16S rRNA gene sequences revealed that the strain 16-SW-7 is a member of the Gammaproteobacteria genus Pseudoalteromonas. The closest relatives of the environmental isolate were Pseudoalteromonas distincta KMM 638T and Pseudoalteromonas paragorgicola KMM 3548T, with the plural paralogous 16S rRNA genes of 99.87-100% similarity. The strain 16-SW-7 grew with 1-10% NaCl and at 4-34°C, and hydrolyzed casein, gelatin, tyrosine, and DNA. The genomic DNA G+C content was 39.3 mol%. The prevalent fatty acids were C16:1 ω7c, C16:0, C17:1 ω8c, C18:1 ω7c, C17:0, and C12:0 3-OH. The polar lipid profile was characterized by the presence of phosphatidylethanolamine, phosphatidylglycerol, two unidentified amino lipids, and three unidentified lipids. The major respiratory quinone was Q-8. The finished genome of the strain 16-SW-7 (GenBank assembly accession number: GCA_005877035.1) has a size of 4,531,445 bp and comprises two circular chromosomes L1 and S1, deposited in the GenBank under the accession numbers CP040558 and CP040559, respectively. The strain 16-SW-7 has the ANI values of 98.2% with KMM 638T and KMM 3548T and the DDH values of 84.4 and 83.5%, respectively, indicating clearly that the three strains belonged to a single species. According to phylogenetic evidence and similarity for the chemotaxonomic and genotypic properties, the strain 16-SW-7 (= KCTC 52772 = KMM 701) represents a novel member of the species Pseudoalteromonas distincta. Also, we have proposed to reclassify Pseudoalteromonas paragorgicola as a later heterotypic synonym of P. distincta based on the rules of priority with the emendation of the species.
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Affiliation(s)
- Olga I Nedashkovkaya
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Sciences, Vladivostok, Russia
| | - Song-Gun Kim
- Korean Collection for Type Cultures, Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea
| | - Larissa A Balabanova
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Sciences, Vladivostok, Russia
| | - Natalia V Zhukova
- A.V. Zhirmunsky National Scientific Center of Marine Biology, Far Eastern Branch of the Russian Academy of Sciences, Vladivostok, Russia
| | - Oksana M Son
- Department of Bioeconomy and Food Security, School of Economics and Management, Far Eastern Federal University, Vladivostok, Russia
| | - Liudmila A Tekutyeva
- Department of Bioeconomy and Food Security, School of Economics and Management, Far Eastern Federal University, Vladivostok, Russia
| | - Valery V Mikhailov
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Sciences, Vladivostok, Russia
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5
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Exploring amino acid and peptide transporters as therapeutic targets to attenuate virulence and antibiotic resistance in Staphylococcus aureus. PLoS Pathog 2021; 17:e1009093. [PMID: 33444418 PMCID: PMC7808641 DOI: 10.1371/journal.ppat.1009093] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
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Casey D, Sleator RD. A genomic analysis of osmotolerance in Staphylococcus aureus. Gene 2020; 767:145268. [PMID: 33157201 DOI: 10.1016/j.gene.2020.145268] [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: 06/04/2020] [Revised: 09/07/2020] [Accepted: 10/20/2020] [Indexed: 12/12/2022]
Abstract
A key phenotypic characteristic of the Gram-positive bacterial pathogen, Staphylococcus aureus, is its ability to grow in low aw environments. A homology transfer based approach, using the well characterised osmotic stress response systems of Bacillus subtilis and Escherichia coli, was used to identify putative osmotolerance loci in Staphylococcus aureus ST772-MRSA-V. A total of 17 distinct putative hyper and hypo-osmotic stress response systems, comprising 78 genes, were identified. The ST772-MRSA-V genome exhibits significant degeneracy in terms of the osmotic stress response; with three copies of opuD, two copies each of nhaK and mrp/mnh, and five copies of opp. Furthermore, regulation of osmotolerance in ST772-MRSA-V appears to be mediated at the transcriptional, translational, and post-translational levels.
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Affiliation(s)
- Dylan Casey
- Department of Biological Sciences, Munster Technological University, Bishopstown Campus, Cork, Ireland
| | - Roy D Sleator
- Department of Biological Sciences, Munster Technological University, Bishopstown Campus, Cork, Ireland.
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Schuster CF, Wiedemann DM, Kirsebom FCM, Santiago M, Walker S, Gründling A. High-throughput transposon sequencing highlights the cell wall as an important barrier for osmotic stress in methicillin resistant Staphylococcus aureus and underlines a tailored response to different osmotic stressors. Mol Microbiol 2019; 113:699-717. [PMID: 31770461 PMCID: PMC7176532 DOI: 10.1111/mmi.14433] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 11/24/2019] [Indexed: 12/28/2022]
Abstract
Staphylococcus aureus is an opportunistic pathogen that can cause soft tissue infections but is also a frequent cause of foodborne illnesses. One contributing factor for this food association is its high salt tolerance allowing this organism to survive commonly used food preservation methods. How this resistance is mediated is poorly understood, particularly during long-term exposure. In this study, we used transposon sequencing (TN-seq) to understand how the responses to osmotic stressors differ. Our results revealed distinctly different long-term responses to NaCl, KCl and sucrose stresses. In addition, we identified the DUF2538 domain containing gene SAUSA300_0957 (gene 957) as essential under salt stress. Interestingly, a 957 mutant was less susceptible to oxacillin and showed increased peptidoglycan crosslinking. The salt sensitivity phenotype could be suppressed by amino acid substitutions in the transglycosylase domain of the penicillin-binding protein Pbp2, and these changes restored the peptidoglycan crosslinking to WT levels. These results indicate that increased crosslinking of the peptidoglycan polymer can be detrimental and highlight a critical role of the bacterial cell wall for osmotic stress resistance. This study will serve as a starting point for future research on osmotic stress response and help develop better strategies to tackle foodborne staphylococcal infections.
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Affiliation(s)
- Christopher F Schuster
- Section of Molecular Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, UK
| | - David M Wiedemann
- Section of Molecular Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, UK
| | - Freja C M Kirsebom
- Section of Molecular Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, UK
| | - Marina Santiago
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA, USA
| | - Suzanne Walker
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA, USA
| | - Angelika Gründling
- Section of Molecular Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, UK
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8
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Torres NJ, Hartson SD, Rogers J, Gustafson JE. Proteomic and Metabolomic Analyses of a Tea-Tree Oil-Selected Staphylococcus aureus Small Colony Variant. Antibiotics (Basel) 2019; 8:antibiotics8040248. [PMID: 31816949 PMCID: PMC6963719 DOI: 10.3390/antibiotics8040248] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 11/25/2019] [Accepted: 11/27/2019] [Indexed: 11/16/2022] Open
Abstract
Tea tree oil (TTO) is hypothesized to kill bacteria by indiscriminately denaturing membrane and protein structures. A Staphylococcus aureus small colony variant (SCV) selected with TTO (SH1000-TTORS-1) demonstrated slowed growth, reduced susceptibility to TTO, a diminutive cell size, and a thinned cell wall. Utilizing a proteomics and metabolomics approach, we have now revealed that the TTO-selected SCV mutant demonstrated defective fatty acid synthesis, an alteration in the expression of genes and metabolites associated with central metabolism, the induction of a general stress response, and a reduction of proteins critical for active growth and translation. SH1000-TTORS-1 also demonstrated an increase in amino acid accumulation and a decrease in sugar content. The reduction in glycolytic pathway proteins and sugar levels indicated that carbon flow through glycolysis and gluconeogenesis is reduced in SH1000-TTORS-1. The increase in amino acid accumulation coincides with the reduced production of translation-specific proteins and the induction of proteins associated with the stringent response. The decrease in sugar content likely deactivates catabolite repression and the increased amino acid pool observed in SH1000-TTORS-1 represents a potential energy and carbon source which could maintain carbon flow though the tricarboxylic acid (TCA) cycle. It is noteworthy that processes that contribute to the production of the TTO targets (proteins and membrane) are reduced in SH1000-TTORS-1. This is one of a few studies describing a mechanism that bacteria utilize to withstand the action of an antiseptic which is thought to inactivate multiple cellular targets.
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9
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Christgen SL, Becker DF. Role of Proline in Pathogen and Host Interactions. Antioxid Redox Signal 2019; 30:683-709. [PMID: 29241353 PMCID: PMC6338583 DOI: 10.1089/ars.2017.7335] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 10/26/2017] [Accepted: 11/14/2017] [Indexed: 01/20/2023]
Abstract
SIGNIFICANCE Proline metabolism has complex roles in a variety of biological processes, including cell signaling, stress protection, and energy production. Proline also contributes to the pathogenesis of various disease-causing organisms. Understanding the mechanisms of how pathogens utilize proline is important for developing new strategies against infectious diseases. Recent Advances: The ability of pathogens to acquire amino acids is critical during infection. Besides protein biosynthesis, some amino acids, such as proline, serve as a carbon, nitrogen, or energy source in bacterial and protozoa pathogens. The role of proline during infection depends on the physiology of the host/pathogen interactions. Some pathogens rely on proline as a critical respiratory substrate, whereas others exploit proline for stress protection. CRITICAL ISSUES Disruption of proline metabolism and uptake has been shown to significantly attenuate virulence of certain pathogens, whereas in other pathogens the importance of proline during infection is not known. Inhibiting proline metabolism and transport may be a useful therapeutic strategy against some pathogens. Developing specific inhibitors to avoid off-target effects in the host, however, will be challenging. Also, potential treatments that target proline metabolism should consider the impact on intracellular levels of Δ1-pyrroline-5-carboxylate, a metabolite intermediate that can have opposing effects on pathogenesis. FUTURE DIRECTIONS Further characterization of how proline metabolism is regulated during infection would provide new insights into the role of proline in pathogenesis. Biochemical and structural characterization of proline metabolic enzymes from different pathogens could lead to new tools for exploring proline metabolism during infection and possibly new therapeutic compounds.
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Affiliation(s)
- Shelbi L. Christgen
- Department of Biochemistry, Redox Biology Center, University of Nebraska−Lincoln, Lincoln, Nebraska
| | - Donald F. Becker
- Department of Biochemistry, Redox Biology Center, University of Nebraska−Lincoln, Lincoln, Nebraska
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10
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Zeden MS, Schuster CF, Bowman L, Zhong Q, Williams HD, Gründling A. Cyclic di-adenosine monophosphate (c-di-AMP) is required for osmotic regulation in Staphylococcus aureus but dispensable for viability in anaerobic conditions. J Biol Chem 2018; 293:3180-3200. [PMID: 29326168 PMCID: PMC5836111 DOI: 10.1074/jbc.m117.818716] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 01/03/2018] [Indexed: 01/15/2023] Open
Abstract
Cyclic di-adenosine monophosphate (c-di-AMP) is a recently discovered signaling molecule important for the survival of Firmicutes, a large bacterial group that includes notable pathogens such as Staphylococcus aureus However, the exact role of this molecule has not been identified. dacA, the S. aureus gene encoding the diadenylate cyclase enzyme required for c-di-AMP production, cannot be deleted when bacterial cells are grown in rich medium, indicating that c-di-AMP is required for growth in this condition. Here, we report that an S. aureus dacA mutant can be generated in chemically defined medium. Consistent with previous findings, this mutant had a severe growth defect when cultured in rich medium. Using this growth defect in rich medium, we selected for suppressor strains with improved growth to identify c-di-AMP-requiring pathways. Mutations bypassing the essentiality of dacA were identified in alsT and opuD, encoding a predicted amino acid and osmolyte transporter, the latter of which we show here to be the main glycine betaine-uptake system in S. aureus. Inactivation of these transporters likely prevents the excessive osmolyte and amino acid accumulation in the cell, providing further evidence for a key role of c-di-AMP in osmotic regulation. Suppressor mutations were also obtained in hepS, hemB, ctaA, and qoxB, coding proteins required for respiration. Furthermore, we show that dacA is dispensable for growth in anaerobic conditions. Together, these findings reveal an essential role for the c-di-AMP signaling network in aerobic, but not anaerobic, respiration in S. aureus.
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Affiliation(s)
- Merve S Zeden
- From the Section of Microbiology and Medical Research Council Centre for Molecular Bacteriology and Infection and
| | - Christopher F Schuster
- From the Section of Microbiology and Medical Research Council Centre for Molecular Bacteriology and Infection and
| | - Lisa Bowman
- From the Section of Microbiology and Medical Research Council Centre for Molecular Bacteriology and Infection and
| | - Qiyun Zhong
- From the Section of Microbiology and Medical Research Council Centre for Molecular Bacteriology and Infection and
| | - Huw D Williams
- Department of Life Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - Angelika Gründling
- From the Section of Microbiology and Medical Research Council Centre for Molecular Bacteriology and Infection and
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11
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Iqbal Z, Seleem MN, Hussain HI, Huang L, Hao H, Yuan Z. Comparative virulence studies and transcriptome analysis of Staphylococcus aureus strains isolated from animals. Sci Rep 2016; 6:35442. [PMID: 27739497 PMCID: PMC5064352 DOI: 10.1038/srep35442] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 09/29/2016] [Indexed: 12/13/2022] Open
Abstract
Several studies have been conducted to check the prevalence of methicillin-resistant strains of Staphylococcus aureus (MRSA) in animals and animal-derived food products but limited data are available regarding their virulence and associated gene expression profile. In the present study, antibiotic resistance and virulence of MRSA and methicillin-sensitive S. aureus animal isolates were determined in vitro by agar dilution, biofilm formation, adhesion, invasion and intracellular survivability assays. In addition, the pathogenicity of these isolates was examined in a murine model of S. aureus sepsis. MRSA1679a, a strain isolated from chicken, was observed to be highly virulent, in cell culture and in mouse model, and exhibited extensive resistant profile. Comparative gene expression profile of MRSA1679a and the reference human MRSA strain (ATCC 29213) was performed using Illumina-based transcriptome and RT-qPCR analyses. Several virulence elements including 22 toxin genes were detected in MRSA animal-isolate. In addition, we observed enhanced expression of crucial virulence regulators, such as sarA and KdpDE in MRSA animal-isolate compared to the human isolate. Collectively, gene expression profile including several virulence and drug-resistance factors confirmed the unique and highly virulent determinants of the MRSA strain of poultry origin which warrants further attention due to significant threat to public health.
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Affiliation(s)
- Zahid Iqbal
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, China
| | - Mohamed N Seleem
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, Indiana, USA
| | - Hafiz Iftikhar Hussain
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, China
| | - Lingli Huang
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, China.,Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Huazhong Agricultural University, Wuhan, China
| | - Haihong Hao
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, China
| | - Zonghui Yuan
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, China.,Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Huazhong Agricultural University, Wuhan, China.,National Reference Laboratory of Veterinary Drug Residues (HZAU) and MAO Key Laboratory for Detection of Veterinary Drug Residues, Huazhong Agricultural University, Wuhan, China
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12
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Schuster CF, Bellows LE, Tosi T, Campeotto I, Corrigan RM, Freemont P, Gründling A. The second messenger c-di-AMP inhibits the osmolyte uptake system OpuC in Staphylococcus aureus. Sci Signal 2016; 9:ra81. [PMID: 27531650 PMCID: PMC5248971 DOI: 10.1126/scisignal.aaf7279] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Staphylococcus aureus is an important opportunistic human pathogen that is highly resistant to osmotic stresses. To survive an increase in osmolarity, bacteria immediately take up potassium ions and small organic compounds known as compatible solutes. The second messenger cyclic diadenosine monophosphate (c-di-AMP) reduces the ability of bacteria to withstand osmotic stress by binding to and inhibiting several proteins that promote potassium uptake. We identified OpuCA, the adenosine triphosphatase (ATPase) component of an uptake system for the compatible solute carnitine, as a c-di-AMP target protein in S aureus and found that the LAC*ΔgdpP strain of S aureus, which overproduces c-di-AMP, showed reduced carnitine uptake. The paired cystathionine-β-synthase (CBS) domains of OpuCA bound to c-di-AMP, and a crystal structure revealed a putative binding pocket for c-di-AMP in the cleft between the two CBS domains. Thus, c-di-AMP inhibits osmoprotection through multiple mechanisms.
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Affiliation(s)
- Christopher F. Schuster
- Section of Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, UK
| | - Lauren E. Bellows
- Section of Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, UK
| | - Tommaso Tosi
- Section of Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, UK
| | - Ivan Campeotto
- Section of Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, UK
| | - Rebecca M. Corrigan
- Section of Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, UK
| | - Paul Freemont
- Section of Structural Biology, Department of Medicine, Imperial College London, London SW7 2AZ, UK
| | - Angelika Gründling
- Section of Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, UK
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13
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Schwan WR, Wetzel KJ. Osmolyte transport in Staphylococcus aureus and the role in pathogenesis. World J Clin Infect Dis 2016; 6:22-27. [PMID: 27429907 PMCID: PMC4943863 DOI: 10.5495/wjcid.v6.i2.22] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 02/18/2016] [Accepted: 04/11/2016] [Indexed: 02/06/2023] Open
Abstract
Osmolyte transport is a pivotal part of bacterial life, particularly in high salt environments. Several low and high affinity osmolyte transport systems have been identified in various bacterial species. A lot of research has centered on characterizing the osmolyte transport systems of Gram-negative bacteria, but less has been done to characterize the same transport systems in Gram-positive bacteria. This review will focus on the previous work that has been done to understand the osmolyte transport systems in the species Staphylococcus aureus and how these transporters may serve dual functions in allowing the bacteria to survive and grow in a variety of environments, including on the surface or within humans or other animals.
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14
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Alternating-access mechanism in conformationally asymmetric trimers of the betaine transporter BetP. Nature 2012; 490:126-30. [DOI: 10.1038/nature11403] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2012] [Accepted: 07/06/2012] [Indexed: 12/12/2022]
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