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Kleinwort KJH, Hobmaier BF, Mayer R, Hölzel C, Degroote RL, Märtlbauer E, Hauck SM, Deeg CA. Mycobacterium avium subsp. paratuberculosis Proteome Changes Profoundly in Milk. Metabolites 2021; 11:metabo11080549. [PMID: 34436489 PMCID: PMC8399727 DOI: 10.3390/metabo11080549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 08/10/2021] [Accepted: 08/18/2021] [Indexed: 11/16/2022] Open
Abstract
Mycobacterium avium subspecies paratuberculosis (MAP) are detectable viable in milk and other dairy products. The molecular mechanisms allowing the adaptation of MAP in these products are still poorly understood. To obtain information about respective adaptation of MAP in milk, we differentially analyzed the proteomes of MAP cultivated for 48 h in either milk at 37 °C or 4 °C or Middlebrook 7H9 broth as a control. From a total of 2197 MAP proteins identified, 242 proteins were at least fivefold higher in abundance in milk. MAP responded to the nutritional shortage in milk with upregulation of 32% of proteins with function in metabolism and 17% in fatty acid metabolism/synthesis. Additionally, MAP upregulated clusters of 19% proteins with roles in stress responses and immune evasion, 19% in transcription/translation, and 13% in bacterial cell wall synthesis. Dut, MmpL4_1, and RecA were only detected in MAP incubated in milk, pointing to very important roles of these proteins for MAP coping with a stressful environment. Dut is essential and plays an exclusive role for growth, MmpL4_1 for virulence through secretion of specific lipids, and RecA for SOS response of mycobacteria. Further, 35 candidates with stable expression in all conditions were detected, which could serve as targets for detection. Data are available via ProteomeXchange with identifier PXD027444.
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Affiliation(s)
- Kristina J. H. Kleinwort
- Chair of Physiology, Department of Veterinary Sciences, LMU Munich, D-82152 Martinsried, Germany; (K.J.H.K.); (B.F.H.); (R.L.D.)
| | - Bernhard F. Hobmaier
- Chair of Physiology, Department of Veterinary Sciences, LMU Munich, D-82152 Martinsried, Germany; (K.J.H.K.); (B.F.H.); (R.L.D.)
| | - Ricarda Mayer
- Chair of Hygiene and Technology of Milk, Department of Veterinary Sciences, LMU Munich, D-85764 Oberschleißheim, Germany; (R.M.); (C.H.); (E.M.)
| | - Christina Hölzel
- Chair of Hygiene and Technology of Milk, Department of Veterinary Sciences, LMU Munich, D-85764 Oberschleißheim, Germany; (R.M.); (C.H.); (E.M.)
- Institute of Animal Breeding and Husbandry, Faculty of Agricultural and Nutritional Sciences, CAU Kiel, D-24098 Kiel, Germany
| | - Roxane L. Degroote
- Chair of Physiology, Department of Veterinary Sciences, LMU Munich, D-82152 Martinsried, Germany; (K.J.H.K.); (B.F.H.); (R.L.D.)
| | - Erwin Märtlbauer
- Chair of Hygiene and Technology of Milk, Department of Veterinary Sciences, LMU Munich, D-85764 Oberschleißheim, Germany; (R.M.); (C.H.); (E.M.)
| | - Stefanie M. Hauck
- Research Unit Protein Science, Helmholtz Center Munich, German Research Center for Environmental Health, D-80939 Munich, Germany;
| | - Cornelia A. Deeg
- Chair of Physiology, Department of Veterinary Sciences, LMU Munich, D-82152 Martinsried, Germany; (K.J.H.K.); (B.F.H.); (R.L.D.)
- Correspondence:
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El-Mowafy M, Elgaml A, Shaaban M. New Approaches for Competing Microbial Resistance and Virulence. Microorganisms 2020. [DOI: 10.5772/intechopen.90388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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3
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Prevalence, antimicrobial susceptibility and plasmid profiling of Vibrio spp. isolated from cultured groupers in Peninsular Malaysia. BMC Microbiol 2019; 19:251. [PMID: 31711432 PMCID: PMC6849203 DOI: 10.1186/s12866-019-1624-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 10/24/2019] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Numerous prevalence studies of Vibrio spp. infection in fish have been extensively reported worldwide, including Malaysia. Unfortunately, information on the prevalence of Vibrio spp. in groupers (Epinephelus spp.) is limited. In this study, groupers obtained from nine farms located at different geographical regions in Malaysia were sampled for the presence of pathogenic Vibrio spp. and their susceptibility profiles against seven antibiotics. RESULTS Out of 270 grouper samples, 195 (72%) were detected with the presence of Vibrio spp. Vibrio communis showed highest prevalence in grouper (28%), followed by V. parahaemolyticus (25%), V. alginolyticus (19%), V. vulnificus (14%), V. rotiferianus (3%), Vibrio sp. (3%), V. campbellii (2%), V. mytili (2%), V. furnissii (2%), V. harveyi (1%), V. tubiashii (1%), V. fluvialis (0.3%) and V. diabolicus (0.3%). Assessment on the antibiotic susceptibility profiles of the Vibrio spp. revealed that majority of the isolates were susceptible to tetracycline, streptomycin, erythromycin and bacitracin, but resistance to ampicillin, penicillin G and vancomycin. The mean MAR index of the Vibrio isolates was 0.51, with 85% of the isolates showed MAR index value of higher than 0.2. Results indicate that the Vibrio spp. were continuously exposed to antibiotics. Furthermore, the plasmid profiles of Vibrio spp. showed that 38.7% of the isolates harbored plasmid with molecular weight of more than 10 kb, while 61.3% were without plasmid. During curing process, Vibrio spp. lost their plasmid, but remained resistant to ampicillin, penicillin G, bacitracin and vancomycin while a few isolates remained resistant to erythromycin, streptomycin and tetracycline. The results suggested that the resistance to antibiotics in isolated Vibrio spp. might be due to chromosomal and plasmid borne. CONCLUSIONS This study demonstrates the prevalence of Vibrio spp. in groupers and the distribution of multidrug resistance strains that could be of concern to the farmers in Malaysia. In addition, data from this study can be further used in fish disease management plan.
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Tan W, Jeong K, Pendru R, Puth S, Hong SH, Lee SE, Rhee JH. The cytochrome d oxidase complex regulated by fexA is an Achilles' heel in the in vivo survival of vibrio vulnificus. Emerg Microbes Infect 2019; 8:1406-1415. [PMID: 31544591 PMCID: PMC6764401 DOI: 10.1080/22221751.2019.1665972] [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] [Indexed: 11/02/2022]
Abstract
Vibrio vulnificus is a halophilic estuarine bacterium causing severe opportunistic infections. To successfully establish an infection, V. vulnificus must adapt to redox fluctuations in vivo. In the present study, we show that deletion of V. vulnificus fexA gene caused hypersensitivity to acid and reactive oxygen species. The ΔfexA mutant exhibited severe in vivo survival defects. For deeper understanding the role of fexA gene on the successful V. vulnificus infection, we analyzed differentially expressed genes in ΔfexA mutant in comparison with wild type under aerobic, anaerobic or in vivo culture conditions by genome-scale DNA microarray analyses. Twenty-two genes were downregulated in the ΔfexA mutant under all three culture conditions. Among them, cydAB appeared to dominantly contribute to the defective phenotypes of the ΔfexA mutant. The fexA deletion induced compensatory point mutations in the cydAB promoter region over subcultures, suggesting essentiality. Those point mutations (PcydSMs) restored bacterial growth, motility, cytotoxicity ATP production and mouse lethality in the ΔfexA mutant. These results indicate that the cydAB operon, being regulated by FexA, plays a crucial role in V. vulnificus survival under redox-fluctuating in vivo conditions. The FexA-CydAB axis should serve an Achilles heel in the development of therapeutic regimens against V. vulnificus infection.
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Affiliation(s)
- Wenzhi Tan
- Clinical Vaccine R&D Center, Chonnam National University Medical School , Hwasun-gun , Republic of Korea.,Department of Microbiology, Chonnam National University Medical School , Hwasun-gun , Republic of Korea.,College of Biology, Hunan University , Changsha , People's People's Republic of China
| | - Kwangjoon Jeong
- Clinical Vaccine R&D Center, Chonnam National University Medical School , Hwasun-gun , Republic of Korea.,Department of Microbiology, Chonnam National University Medical School , Hwasun-gun , Republic of Korea.,Vaxcell-Bio Therapeutics , Hwasun-gun , Republic of Korea
| | - Raghunath Pendru
- Clinical Vaccine R&D Center, Chonnam National University Medical School , Hwasun-gun , Republic of Korea.,Department of Microbiology, Chonnam National University Medical School , Hwasun-gun , Republic of Korea
| | - Sao Puth
- Clinical Vaccine R&D Center, Chonnam National University Medical School , Hwasun-gun , Republic of Korea.,Department of Microbiology, Chonnam National University Medical School , Hwasun-gun , Republic of Korea.,Combinatorial Tumor Immunotherapy Research Center, Chonnam National University , Hwasun-gun , Republic of Korea
| | - Seol Hee Hong
- Clinical Vaccine R&D Center, Chonnam National University Medical School , Hwasun-gun , Republic of Korea.,Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University , Gwangju , Republic of Korea
| | - Shee Eun Lee
- Clinical Vaccine R&D Center, Chonnam National University Medical School , Hwasun-gun , Republic of Korea.,Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University , Gwangju , Republic of Korea
| | - Joon Haeng Rhee
- Clinical Vaccine R&D Center, Chonnam National University Medical School , Hwasun-gun , Republic of Korea.,Department of Microbiology, Chonnam National University Medical School , Hwasun-gun , Republic of Korea.,Vaxcell-Bio Therapeutics , Hwasun-gun , Republic of Korea.,Combinatorial Tumor Immunotherapy Research Center, Chonnam National University , Hwasun-gun , Republic of Korea
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5
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In Vitro Synergy and In Vivo Activity of Tigecycline-Ciprofloxacin Combination Therapy against Vibrio vulnificus Sepsis. Antimicrob Agents Chemother 2019; 63:AAC.00310-19. [PMID: 31332060 DOI: 10.1128/aac.00310-19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 06/29/2019] [Indexed: 12/17/2022] Open
Abstract
The mortality rate associated with Vibrio vulnificus sepsis remains high. An in vitro time-kill assay revealed synergism between tigecycline and ciprofloxacin. The survival rate was significantly higher in mice treated with tigecycline plus ciprofloxacin than in mice treated with cefotaxime plus minocycline. Thus, combination treatment with tigecycline-ciprofloxacin may be an effective novel antibiotic regimen for V. vulnificus sepsis.
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Schmid LM, Ohler L, Möhlmann T, Brachmann A, Muiño JM, Leister D, Meurer J, Manavski N. PUMPKIN, the Sole Plastid UMP Kinase, Associates with Group II Introns and Alters Their Metabolism. PLANT PHYSIOLOGY 2019; 179:248-264. [PMID: 30409856 PMCID: PMC6324238 DOI: 10.1104/pp.18.00687] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 10/29/2018] [Indexed: 05/07/2023]
Abstract
The chloroplast hosts photosynthesis and a variety of metabolic pathways that are essential for plant viability and acclimation processes. In this study, we show that the sole plastid UMP kinase (PUMPKIN) in Arabidopsis (Arabidopsis thaliana) associates specifically with the introns of the plastid transcripts trnG-UCC, trnV-UAC, petB, petD, and ndhA in vivo, as revealed by RNA immunoprecipitation coupled with deep sequencing (RIP-Seq); and that PUMPKIN can bind RNA efficiently in vitro. Analyses of target transcripts showed that PUMPKIN affects their metabolism. Null alleles and knockdowns of pumpkin were viable but clearly affected in growth, plastid translation, and photosynthetic performance. In pumpkin mutants, the levels of many plastid transcripts were reduced, while the amounts of others were increased, as revealed by RNA-Seq analysis. PUMPKIN is a homomultimeric, plastid-localized protein that forms in vivo RNA-containing megadalton-sized complexes and catalyzes the ATP-dependent conversion of UMP to UDP in vitro with properties characteristic of known essential eubacterial UMP kinases. A moonlighting function of PUMPKIN combining RNA and pyrimidine metabolism is discussed.
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Affiliation(s)
- Lisa-Marie Schmid
- Plant Sciences, Faculty of Biology, Ludwig-Maximilians-University Munich, Großhaderner Street 2-4, 82152 Planegg-Martinsried, Germany
| | - Lisa Ohler
- Plant Physiology, Faculty of Biology, University of Kaiserslautern, Erwin Schrödinger Street, 67653 Kaiserslautern, Germany
| | - Torsten Möhlmann
- Plant Physiology, Faculty of Biology, University of Kaiserslautern, Erwin Schrödinger Street, 67653 Kaiserslautern, Germany
| | - Andreas Brachmann
- Genetics, Faculty of Biology, Ludwig-Maximilians-University Munich, Großhaderner Street 2-4, 82152 Planegg-Martinsried, Germany
| | - Jose M Muiño
- Humboldt University, Faculty of Life Science, Philipp Street 13, 10115 Berlin, Germany
| | - Dario Leister
- Plant Sciences, Faculty of Biology, Ludwig-Maximilians-University Munich, Großhaderner Street 2-4, 82152 Planegg-Martinsried, Germany
| | - Jörg Meurer
- Plant Sciences, Faculty of Biology, Ludwig-Maximilians-University Munich, Großhaderner Street 2-4, 82152 Planegg-Martinsried, Germany
| | - Nikolay Manavski
- Plant Sciences, Faculty of Biology, Ludwig-Maximilians-University Munich, Großhaderner Street 2-4, 82152 Planegg-Martinsried, Germany
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Galactose-1-phosphate uridyltransferase (GalT), an in vivo-induced antigen of Actinobacillus pleuropneumoniae serovar 5b strain L20, provided immunoprotection against serovar 1 strain MS71. PLoS One 2018; 13:e0198207. [PMID: 29856812 PMCID: PMC5983418 DOI: 10.1371/journal.pone.0198207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 05/15/2018] [Indexed: 11/19/2022] Open
Abstract
GALT is an important antigen of Actinobacillus pleuropneumoniae (APP), which was shown to provide partial protection against APP infection in a previous study in our lab. The main purpose of the present study is to investigate GALT induced cross-protection between different APP serotypes and elucidate key mechanisms of the immune response to GALT antigenic stimulation. Bioinformatic analysis demonstrated that galT is a highly conserved gene in APP, widely distributed across multiple pathogenic strains. Homologies between any two strains ranges from 78.9% to 100% regarding the galT locus. Indirect enzyme-linked immunosorbent assay (ELISA) confirmed that GALT specific antibodies could not be induced by inactivated APP L20 or MS71 whole cell bacterin preparations. A recombinant fusion GALT protein derived from APP L20, however has proven to be an effective cross-protective antigen against APP sevorar 1 MS71 (50%, 4/8) and APP sevorar 5b L20 (75%, 6/8). Histopathological examinations have confirmed that recombinant GALT vaccinated animals showed less severe pathological signs in lung tissues than negative controls after APP challenge. Immunohistochemical (IHC) analysis indicated that the infiltration of neutrophils in the negative group is significantly increased compared with that in the normal control (P<0.001) and that in surviving animals is decreased compared to the negative group. Anti-GALT antibodies were shown to mediate phagocytosis of neutrophils. After interaction with anti-GALT antibodies, survival rate of APP challenged vaccinated animals was significantly reduced (P<0.001). This study demonstrated that GALT is an effective cross-protective antigen, which could be used as a potential vaccine candidate against multiple APP serotypes.
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8
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Li S, Su Z, Zhang C, Xu Z, Chang X, Zhu J, Xiao R, Li L, Zhou R. Identification of drug target candidates of the swine pathogen Actinobacillus pleuropneumoniae by construction of protein-protein interaction network. Genes Genomics 2018; 40:847-856. [PMID: 30047117 DOI: 10.1007/s13258-018-0691-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 04/12/2018] [Indexed: 01/31/2023]
Abstract
Porcine pleuropneumonia caused by Actinobacillus pleuropneumoniae has led to severe economic losses in the pig industry worldwide. A. pleuropneumoniae displays various levels of antimicrobial resistance, leading to the dire need to identify new drug targets. Protein-protein interaction (PPI) network can aid the identification of drug targets by discovering essential proteins during the life of bacteria. The aim of this study is to identify drug target candidates of A. pleuropneumoniae from essential proteins in PPI network. The homologous protein mapping method (HPM) was utilized to construct A. pleuropneumoniae PPI network. Afterwards, the subnetwork centered with H-NS was selected to verify the PPI network using bacterial two-hybrid assays. Drug target candidates were identified from the hub proteins by analyzing the topology of the network using interaction degree and homologous comparison with the pig proteome. An A. pleuropneumoniae PPI network containing 2737 non-redundant interaction pairs among 533 proteins was constructed. These proteins were distributed in 21 COG functional categories and 28 KEGG metabolic pathways. The A. pleuropneumoniae PPI network was scale free and the similar topological tendencies were found when compared with other bacteria PPI network. Furthermore, 56.3% of the H-NS subnetwork interactions were validated. 57 highly connected proteins (hub proteins) were identified from the A. pleuropneumoniae PPI network. Finally, 9 potential drug targets were identified from the hub proteins, with no homologs in swine. This study provides drug target candidates, which are promising for further investigations to explore lead compounds against A. pleuropneumoniae.
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Affiliation(s)
- Siqi Li
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Shizishan Street 1, Wuhan, 430070, China
| | - Zhipeng Su
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Shizishan Street 1, Wuhan, 430070, China
| | - Chengjun Zhang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Shizishan Street 1, Wuhan, 430070, China
| | - Zhuofei Xu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Shizishan Street 1, Wuhan, 430070, China.,Cooperative Innovation Center of Sustainable Pig Production, Wuhan, 430070, China
| | - Xiaoping Chang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Shizishan Street 1, Wuhan, 430070, China
| | - Jiawen Zhu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Shizishan Street 1, Wuhan, 430070, China.,Institute of Animal Science, Chengdu Academy of Agriculture and Forestry Sciences, Chengdu, 611130, China
| | - Ran Xiao
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Shizishan Street 1, Wuhan, 430070, China
| | - Lu Li
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Shizishan Street 1, Wuhan, 430070, China. .,Cooperative Innovation Center of Sustainable Pig Production, Wuhan, 430070, China.
| | - Rui Zhou
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Shizishan Street 1, Wuhan, 430070, China. .,Cooperative Innovation Center of Sustainable Pig Production, Wuhan, 430070, China.
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Chimetto Tonon LA, Thompson JR, Moreira APB, Garcia GD, Penn K, Lim R, Berlinck RGS, Thompson CC, Thompson FL. Quantitative Detection of Active Vibrios Associated with White Plague Disease in Mussismilia braziliensis Corals. Front Microbiol 2017; 8:2272. [PMID: 29204142 PMCID: PMC5698304 DOI: 10.3389/fmicb.2017.02272] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 11/03/2017] [Indexed: 12/30/2022] Open
Abstract
Over recent decades several coral diseases have been reported as a significant threat to coral reef ecosystems causing the decline of corals cover and diversity around the world. The development of techniques that improve the ability to detect and quantify microbial agents involved in coral disease will aid in the elucidation of disease cause, facilitating coral disease detection and diagnosis, identification and pathogen monitoring, pathogen sources, vectors, and reservoirs. The genus Vibrio is known to harbor pathogenic strains to marine organisms. One of the best-characterized coral pathogens is Vibrio coralliilyticus, an aetilogic agent of White Plague Disease (WPD). We used Mussismilia coral tissue (healthy and diseased specimens) to develop a rapid reproducible detection system for vibrios based on RT-QPCR and SYBR chemistry. We were able to detect total vibrios in expressed RNA targeting the 16S rRNA gene at 5.23 × 106 copies/μg RNA and V. coralliilyticus targeting the pyrH gene at 5.10 × 103 copies/μg RNA in coral tissue. Detection of V. coralliilyticus in diseased and in healthy samples suggests that WPD in the Abrolhos Bank may be caused by a consortium of microorganism and not only a single pathogen. We developed a more practical and economic system compared with probe uses for the real-time detection and quantification of vibrios from coral tissues by using the 16S rRNA and pyrH gene. This qPCR assay is a reliable tool for the monitoring of coral pathogens, and can be useful to prevent, control, or reduce impacts in this ecosystem.
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Affiliation(s)
- Luciane A Chimetto Tonon
- Laboratory of Organic Chemistry of Biological Systems, Chemical Institute of São Carlos, University of São Paulo, São Carlos, Brazil.,Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States.,Laboratory of Microbiology, Institute of Biology, SAGE-COPPE, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Janelle R Thompson
- Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Ana P B Moreira
- Laboratory of Microbiology, Institute of Biology, SAGE-COPPE, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Gizele D Garcia
- Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Kevin Penn
- Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Rachelle Lim
- Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Roberto G S Berlinck
- Laboratory of Organic Chemistry of Biological Systems, Chemical Institute of São Carlos, University of São Paulo, São Carlos, Brazil
| | - Cristiane C Thompson
- Laboratory of Microbiology, Institute of Biology, SAGE-COPPE, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Fabiano L Thompson
- Laboratory of Microbiology, Institute of Biology, SAGE-COPPE, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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10
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Liu D, Hao K, Wang W, Peng C, Dai Y, Jin R, Xu W, He L, Wang H, Wang H, Zhang L, Wang Q. Rv2629 Overexpression Delays Mycobacterium smegmatis and Mycobacteria tuberculosis Entry into Log-Phase and Increases Pathogenicity of Mycobacterium smegmatis in Mice. Front Microbiol 2017; 8:2231. [PMID: 29187838 PMCID: PMC5694894 DOI: 10.3389/fmicb.2017.02231] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 10/31/2017] [Indexed: 12/11/2022] Open
Abstract
Objective: The aim of the present study was to explore the potential biological role of Rv2629 in Mycobacterium smegmatis and Mycobacterium tuberculosis.Methods: Recombinant wild type and mutant Rv2629 strains were constructed. Rv2629 expression was evaluated by real-time PCR and western blot. Microarray and interaction network analyses were used to identify the gene interactions associated with wild type and mutant Rv2629. Bacterial growth was assessed in Balb/c mice infected with wild type and mutant Rv2629 strains using CFU assay and histological analysis of the organs. Results: Overexpression of Rv2629 could delay the entry of the Mycobacterium tuberculosis cells into the log-phase, while Rv2629 decreased the number of ribosomes and the expression of uridylate kinase in Mycobacterium smegmatis. The Gene Ontology (GO) and pathway analysis indicated that 122 genes correlated with wild type Rv2629, whereas the Rv2629 mutation led to decrease in the ribosome production, oxidative phosphorylation, and virulence in Mycobacterium tuberculosis. Overexpression of Rv2629 slightly enhanced the drug resistance of Mycobacterium smegmatis to antibiotics, and increased its survival and pathogenicity in Balb/c mice. Conclusion: It is suggested that Rv2629 is involved in the survival of the clinical drug-resistant strain via bacterial growth repression and bacterial persistence induction.
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Affiliation(s)
- Dan Liu
- Department of Immunology and Pathogen Biology, Shanghai University of Traditional Chinese Medicine, Shanghai, China.,State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, China
| | - Kewei Hao
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, China
| | - Wenjie Wang
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, China
| | - Chao Peng
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, China
| | - Yue Dai
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, China
| | - Ruiliang Jin
- Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Wenxi Xu
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, China
| | - Lei He
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, China
| | - Hongyan Wang
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, China
| | - Honghai Wang
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, China
| | - Lu Zhang
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, China
| | - Qingzhong Wang
- Shanghai Centre for Clinical Laboratory, Shanghai, China
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11
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Elgaml A, Miyoshi SI. Regulation systems of protease and hemolysin production inVibrio vulnificus. Microbiol Immunol 2017; 61:1-11. [DOI: 10.1111/1348-0421.12465] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 12/19/2016] [Accepted: 01/16/2017] [Indexed: 11/29/2022]
Affiliation(s)
- Abdelaziz Elgaml
- Microbiology and Immunology Department; Faculty of Pharmacy; Mansoura University; Elgomhouria Street Mansoura 35516 Egypt
| | - Shin-Ichi Miyoshi
- Graduate School of Medicine; Dentistry and Pharmaceutical Sciences; Okayama University; 1-1-1 Tsushima-Naka Kita-Ku Okayama 700-8530 Japan
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12
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Elgaml A, Miyoshi SI. Role of the Histone-Like Nucleoid Structuring Protein (H-NS) in the Regulation of Virulence Factor Expression and Stress Response in Vibrio vulnificus. Biocontrol Sci 2016; 20:263-74. [PMID: 26699858 DOI: 10.4265/bio.20.263] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
Temperature is one of the important parameters regulating the expression of virulence factors in bacteria. The global regulator, a histone-like nucleoid structuring protein (H-NS), is known to play a crucial role in this regulation. In the present study, we first clarified the role of H-NS in the temperature-dependent regulation of virulence factor production in Vibrio vulnificus, including that of the cytolytic toxin (V. vulnificus hemolysin: VVH) and the proteolytic enzyme (V. vulnificus protease: VVP). The expression of hns itself was subjected to temperature regulation, where hns was expressed more at 26 ℃ than at 37 ℃. VVH production and the expression of its gene vvhA were increased by disruption of the hns gene. H-NS appeared to affect the vvhA expression by the well-documented transcriptional silencing mechanism. On the other hand, hns disruption resulted in the reduction of VVP production and the expression of its gene vvpE. H-NS was suggested to positively regulate vvpE expression through the increase in the level of the rpoS mRNA. Moreover, H-NS was found to contribute to the survival of V. vulnificus in stressful environments. When compared to the wild type strain, the hns mutant exhibited reduced survival rates when subjected to acidic pH, hyperosmotic and oxidative stress.
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Affiliation(s)
- Abdelaziz Elgaml
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University
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Temperature Change Induces the Expression of vuuA Encoding Vulnibactin Receptor and crp Encoding Cyclic AMP Receptor Protein in Vibrio vulnificus. Curr Microbiol 2016; 73:54-64. [PMID: 27016238 DOI: 10.1007/s00284-016-1026-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 02/04/2016] [Indexed: 12/19/2022]
Abstract
Upon entering the human body, Vibrio vulnificus, a gram-negative marine bacterium, must withstand a temperature change (TC) from 25 to 37 °C. This bacterium acquires iron mainly via the vulnibactin receptor (VuuA)-mediated iron uptake system (IUS), which is under the positive control of cyclic AMP receptor protein (CRP), a global regulator responsible for catabolite repression. In this study, we examined the effect of TC on the expression of vuuA and crp, and the reciprocal relation between VuuA-mediated IUS and CRP under iron-limited conditions. Iron limitation increased vuuA expression but decreased crp expression. TC resulted in increased vuuA and crp expression. A crp or vuuA mutation reciprocally decreased vuuA or crp expression. TC could increase vuuA or crp expression even in a crp- or vuuA-mutated background. These results indicate that TC increases the expression of both vuuA and crp by facilitating metabolism under iron-limited conditions, and that CRP and VuuA-mediated IUS interact coordinately toward optimal metabolism in V. vulnificus.
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All Three TonB Systems Are Required for Vibrio vulnificus CMCP6 Tissue Invasiveness by Controlling Flagellum Expression. Infect Immun 2015; 84:254-65. [PMID: 26527216 DOI: 10.1128/iai.00821-15] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 10/24/2015] [Indexed: 01/22/2023] Open
Abstract
TonB systems actively transport iron-bound substrates across the outer membranes of Gram-negative bacteria. Vibrio vulnificus CMCP6, which causes fatal septicemia and necrotizing wound infections, possesses three active TonB systems. It is not known why V. vulnificus CMCP6 has maintained three TonB systems throughout its evolution. The TonB1 and TonB2 systems are relatively well characterized, while the pathophysiological function of the TonB3 system is still elusive. A reverse transcription-PCR (RT-PCR) study showed that the tonB1 and tonB2 genes are preferentially induced in vivo, whereas tonB3 is persistently transcribed, albeit at low expression levels, under both in vitro and in vivo conditions. The goal of the present study was to elucidate the raison d'être of these three TonB systems. In contrast to previous studies, we constructed in-frame single-, double-, and triple-deletion mutants of the entire structural genes in TonB loci, and the changes in various virulence-related phenotypes were evaluated. Surprisingly, only the tonB123 mutant exhibited a significant delay in killing eukaryotic cells, which was complemented in trans with any TonB operon. Very interestingly, we discovered that flagellum biogenesis was defective in the tonB123 mutant. The loss of flagellation contributed to severe defects in motility and adhesion of the mutant. Because of the difficulty of making contact with host cells, the mutant manifested defective RtxA1 toxin production, which resulted in impaired invasiveness, delayed cytotoxicity, and decreased lethality for mice. Taken together, these results indicate that a series of virulence defects in all three TonB systems of V. vulnificus CMCP6 coordinately complement each other for iron assimilation and full virulence expression by ensuring flagellar biogenesis.
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SongLin G, PanPan L, JianJun F, JinPing Z, Peng L, LiHua D. A novel recombinant bivalent outer membrane protein of Vibrio vulnificus and Aeromonas hydrophila as a vaccine antigen of American eel (Anguilla rostrata). FISH & SHELLFISH IMMUNOLOGY 2015; 43:477-484. [PMID: 25655329 DOI: 10.1016/j.fsi.2015.01.017] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 01/08/2015] [Accepted: 01/22/2015] [Indexed: 06/04/2023]
Abstract
The immogenicity of a novel vaccine antigen was evaluated after immunized American eels (Anguilla rostrata) with a recombinant bivalent expressed outer membrane protein (OMP) of Vibrio vulnificus and Aeromonas hydrophila. Three groups of eels were intraperitoneal (i.p) injected with phosphate-buffered saline (PBS group), formaline-killed-whole-cell (FKC) of A. hydrophila and V. vulnificus (FKC group) or the bivalent OMP (OMP group). On 14, 21, 28 and 42 days post-vaccination respectively, proliferation of the whole blood cells, titers of specific antibody and lysozyme activities of experimental eels were detected. On 28 day post-vaccination, eels from three groups were challenged by i.p injection of live A. hydrophila or V. vulnificus. The results showed that, compared with the PBS group, proliferation of whole blood cells in OMP group was significant enhanced on 28 days, and the serum titers of anti-A.hydrophila and anti-V. vulnificus antibody in eels of FKC and OMP group were significant increased on 14, 21 and 28d. Lysozyme Activities in serum, skin mucus, liver and kidney were significant changed between the three groups. Relative Percent Survival (RPS) after challenged A. hydrophila in KFC vs. PBS group and OMP vs. PBS group were 62.5% and 50% respectively, and the RPS challenged V. vulnificus in FKC and OMP vs. PBS group were 37.5% and 50% respectively. These results suggest that American eels immunized with the bivalent OMP would positively affect specific as well as non-specific immune parameters and protect against infection by the two pathogens in fresh water farming.
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Affiliation(s)
- Guo SongLin
- Fishery College of Jimei University/Engineering Research Center of Modern Eel Industrial Technology of the Ministry of Education, PRC. Jimei University, Xiamen, Fujian 361021, China.
| | - Lu PanPan
- Fishery College of Jimei University/Engineering Research Center of Modern Eel Industrial Technology of the Ministry of Education, PRC. Jimei University, Xiamen, Fujian 361021, China
| | - Feng JianJun
- Fishery College of Jimei University/Engineering Research Center of Modern Eel Industrial Technology of the Ministry of Education, PRC. Jimei University, Xiamen, Fujian 361021, China
| | - Zhao JinPing
- Fishery College of Jimei University/Engineering Research Center of Modern Eel Industrial Technology of the Ministry of Education, PRC. Jimei University, Xiamen, Fujian 361021, China
| | - Lin Peng
- Fishery College of Jimei University/Engineering Research Center of Modern Eel Industrial Technology of the Ministry of Education, PRC. Jimei University, Xiamen, Fujian 361021, China
| | - Duan LiHua
- Fishery College of Jimei University/Engineering Research Center of Modern Eel Industrial Technology of the Ministry of Education, PRC. Jimei University, Xiamen, Fujian 361021, China
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Kashimoto T, Iwasaki C, Gojo M, Sugiyama H, Yoshioka K, Yamamoto Y, Okamura M, Susa N, Ueno S. Vibrio vulnificus detected in the spleen leads to fatal outcome in a mouse oral infection model. FEMS Microbiol Lett 2015; 362:fnv005. [PMID: 25790509 DOI: 10.1093/femsle/fnv005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Vibrio vulnificus causes rapid disseminating septicemia by oral infection in infected individuals who have an underlying disease, especially chronic liver diseases. Although the elucidation of specific risk factors for V. vulnificus infection in patients with liver diseases is of urgent importance, no appropriate experimental animal model that mimics the liver diseases in this bacterial infection has been available so far. To discover these risk factors, we generated a liver disordered mouse by performing bile duct ligation (BDL). Hepatitis developed in the BDL mice; however, this did not affect mortality in mice after orogastric administration of V. vulnificus, suggesting that the liver disorders caused by the BDL were not risk factors for V. vulnificus septicemia. When the dead and surviving mice were compared, V. vulnificus could be detected from the spleen only in the dead group. Furthermore, significantly higher numbers of V. vulnificus were detected from the intestines in the dead group than in the surviving group ( P < 0.001). These findings suggested that proliferation of the challenge inoculum in the intestine was needed for the oral infection with V. vulnificus, and that the elimination of V. vulnificus in the liver and/or spleen plays a critical role in survival of the host.
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Affiliation(s)
- Takashige Kashimoto
- Laboratory of Veterinary Public Health, School of Veterinary Medicine, Kitasato University, Higashi 23-35-1, Towada, Aomori 034-8628, Japan
| | - Chiemi Iwasaki
- Laboratory of Veterinary Public Health, School of Veterinary Medicine, Kitasato University, Higashi 23-35-1, Towada, Aomori 034-8628, Japan
| | - Masanori Gojo
- Laboratory of Veterinary Public Health, School of Veterinary Medicine, Kitasato University, Higashi 23-35-1, Towada, Aomori 034-8628, Japan
| | - Hiroyuki Sugiyama
- Laboratory of Veterinary Public Health, School of Veterinary Medicine, Kitasato University, Higashi 23-35-1, Towada, Aomori 034-8628, Japan
| | - Kazuki Yoshioka
- Laboratory of Veterinary Anatomy, School of Veterinary Medicine, Kitasato University, 23-35-1 Higashi, Towada, Aomori 034-8628, Japan
| | - Yuji Yamamoto
- Laboratory of Biomolecular Function, School of Veterinary Medicine, Kitasato University, 23-35-1 Higashi, Towada, Aomori 034-8628, Japan
| | - Masashi Okamura
- Laboratory of Zoonoses, School of Veterinary Medicine, Kitasato University, Higashi 23-35-1, Towada Aomori 034-8628, Japan
| | - Nobuyuki Susa
- Laboratory of Veterinary Public Health, School of Veterinary Medicine, Kitasato University, Higashi 23-35-1, Towada, Aomori 034-8628, Japan
| | - Shunji Ueno
- Laboratory of Veterinary Public Health, School of Veterinary Medicine, Kitasato University, Higashi 23-35-1, Towada, Aomori 034-8628, Japan
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Mou KT, Muppirala UK, Severin AJ, Clark TA, Boitano M, Plummer PJ. A comparative analysis of methylome profiles of Campylobacter jejuni sheep abortion isolate and gastroenteric strains using PacBio data. Front Microbiol 2015; 5:782. [PMID: 25642218 PMCID: PMC4294202 DOI: 10.3389/fmicb.2014.00782] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 12/20/2014] [Indexed: 12/13/2022] Open
Abstract
Campylobacter jejuni is a leading cause of human gastrointestinal disease and small ruminant abortions in the United States. The recent emergence of a highly virulent, tetracycline-resistant C. jejuni subsp. jejuni sheep abortion clone (clone SA) in the United States, and that strain's association with human disease, has resulted in a heightened awareness of the zoonotic potential of this organism. Pacific Biosciences' Single Molecule, Real-Time sequencing technology was used to explore the variation in the genome-wide methylation patterns of the abortifacient clone SA (IA3902) and phenotypically distinct gastrointestinal-specific C. jejuni strains (NCTC 11168 and 81-176). Several notable differences were discovered that distinguished the methylome of IA3902 from that of 11168 and 81-176: identification of motifs novel to IA3902, genome-specific hypo- and hypermethylated regions, strain level variability in genes methylated, and differences in the types of methylation motifs present in each strain. These observations suggest a possible role of methylation in the contrasting disease presentations of these three C. jejuni strains. In addition, the methylation profiles between IA3902 and a luxS mutant were explored to determine if variations in methylation patterns could be identified that might explain the role of LuxS-dependent methyl recycling in IA3902 abortifacient potential.
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Affiliation(s)
- Kathy T Mou
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University Ames, IA, USA
| | - Usha K Muppirala
- Genome Informatics Facility, Office of Biotechnology, Iowa State University Ames, IA, USA
| | - Andrew J Severin
- Genome Informatics Facility, Office of Biotechnology, Iowa State University Ames, IA, USA
| | | | | | - Paul J Plummer
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University Ames, IA, USA
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Monoclonal antibodies against Vibrio vulnificus RtxA1 elicit protective immunity through distinct mechanisms. Infect Immun 2014; 82:4813-23. [PMID: 25156730 DOI: 10.1128/iai.02130-14] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Vibrio vulnificus causes rapidly progressing septicemia with an extremely high mortality rate (≥50%), even with aggressive antibiotic treatment. The bacteria secrete multifunctional autoprocessing repeats-in-toxin (MARTX) toxins, which are involved in the pathogenesis of Gram-negative Vibrio species. Recently, we reported that immunization with the C-terminal region of V. vulnificus RtxA1/MARTXVv, RtxA1-C, elicits a protective immune response against V. vulnificus through a poorly defined mechanism. In this study, we generated a panel of new monoclonal antibodies (MAbs) against V. vulnificus RtxA1-C and investigated their protective efficacies and mechanisms in a mouse model of infection. Prophylactic administration of seven MAbs strongly protected mice against lethal V. vulnificus infection (more than 90% survival). Moreover, three of these MAbs (21RA, 24RA, and 47RA) demonstrated marked efficacy as postexposure therapy. Notably, 21RA was therapeutically effective against lethal V. vulnificus infection by a variety of routes. Using Fab fragments and a neutropenic mouse model, we showed that 21RA and 24RA mediate protection from V. vulnificus infection through an Fc-independent and/or neutrophil-independent pathway. In contrast, 47RA-mediated protection was dependent on its Fc region and was reduced to 50% in neutropenic mice compared with 21RA-mediated and 24RA-mediated protection. Bacteriological study indicated that 21RA appears to enhance the clearance of V. vulnificus from the blood. Overall, these studies suggest that humoral immunity controls V. vulnificus infection through at least two different mechanisms. Furthermore, our panel of MAbs could provide attractive candidates for the further development of immunoprophylaxis/therapeutics and other therapies against V. vulnificus that target the MARTX toxin.
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In vivo efficacy of the combination of ciprofloxacin and cefotaxime against Vibrio vulnificus sepsis. PLoS One 2014; 9:e101118. [PMID: 24978586 PMCID: PMC4076242 DOI: 10.1371/journal.pone.0101118] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Accepted: 06/03/2014] [Indexed: 12/18/2022] Open
Abstract
Objectives The invivo efficacy of a cefotaxime-ciprofloxacin combination against Vibrio vulnificus and the effects on rtxA1 expression of commonly used antibiotics are unknown. Methods In vitro time-kill studies were performed to evaluate synergism. Female BALB/c mice were injected subcutaneously with 1×107 or 1×108 cfu of V. vulnificus. Antibiotic therapy was initiated at 2 h after inoculation in the following four therapy groups: cefotaxime; ciprofloxacin; cefotaxime-plus-ciprofloxacin; and cefotaxime-plus-minocycline. The cytotoxicity of V. vulnificus for HeLa cells was measured using the lactate dehydrogenase assay; rtxA1 transcription was measured in a transcriptional reporter strain using a β-galactosidase assay. Results In vitro time-kill assays exhibited synergism between cefotaxime and ciprofloxacin. In the animal experiments, the 96-h survival rate for the cefotaxime-plus-ciprofloxacin group (85%; 17/20) was significantly higher than that of the cefotaxime-plus-minocycline (35%; 7/20) and cefotaxime alone (0%; 0/20) groups (P<0.05 for both). Bacterial counts in the liver and spleen were significantly lower in the cefotaxime-plus-ciprofloxacin group 24 and 48 h after treatment, relative to the other groups. At sub-inhibitory concentrations, ciprofloxacin inhibited more effectively rtxA1 transcription and mammalian cell cytotoxicity than either minocycline or cefotaxime (P<0.05 for both). Conclusions Ciprofloxacin is more effective at reducing rtxA1 transcription and subsequent cytotoxicity than either minocycline or cefotaxime, and the combination of ciprofloxacin and cefotaxime was more effective in clearing V. vulnificus invivo than previously used regimens. These data suggest that the combination of ciprofloxacin and cefotaxime is an effective option for the treatment of V. vulnificus sepsis in humans.
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Das S, Dash HR, Mangwani N, Chakraborty J, Kumari S. Understanding molecular identification and polyphasic taxonomic approaches for genetic relatedness and phylogenetic relationships of microorganisms. J Microbiol Methods 2014; 103:80-100. [PMID: 24886836 DOI: 10.1016/j.mimet.2014.05.013] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Revised: 05/22/2014] [Accepted: 05/22/2014] [Indexed: 12/29/2022]
Abstract
The major proportion of earth's biological diversity is inhabited by microorganisms and they play a useful role in diversified environments. However, taxonomy of microorganisms is progressing at a snail's pace, thus less than 1% of the microbial population has been identified so far. The major problem associated with this is due to a lack of uniform, reliable, advanced, and common to all practices for microbial identification and systematic studies. However, recent advances have developed many useful techniques taking into account the house-keeping genes as well as targeting other gene catalogues (16S rRNA, rpoA, rpoB, gyrA, gyrB etc. in case of bacteria and 26S, 28S, β-tubulin gene in case of fungi). Some uncultivable approaches using much advanced techniques like flow cytometry and gel based techniques have also been used to decipher microbial diversity. However, all these techniques have their corresponding pros and cons. In this regard, a polyphasic taxonomic approach is advantageous because it exploits simultaneously both conventional as well as molecular identification techniques. In this review, certain aspects of the merits and limitations of different methods for molecular identification and systematics of microorganisms have been discussed. The major advantages of the polyphasic approach have also been described taking into account certain groups of bacteria as case studies to arrive at a consensus approach to microbial identification.
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Affiliation(s)
- Surajit Das
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology, Rourkela 769 008, Odisha, India.
| | - Hirak R Dash
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology, Rourkela 769 008, Odisha, India
| | - Neelam Mangwani
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology, Rourkela 769 008, Odisha, India
| | - Jaya Chakraborty
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology, Rourkela 769 008, Odisha, India
| | - Supriya Kumari
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology, Rourkela 769 008, Odisha, India
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Ford DC, Ireland PM, Bullifent HL, Saint RJ, McAlister EV, Sarkar-Tyson M, Oyston PCF. Construction of an inducible system for the analysis of essential genes in Yersinia pestis. J Microbiol Methods 2014; 100:1-7. [PMID: 24524852 DOI: 10.1016/j.mimet.2014.01.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 01/20/2014] [Accepted: 01/25/2014] [Indexed: 01/14/2023]
Abstract
Yersinia pestis, a Gram negative bacterium, causes bubonic and pneumonic plague. Emerging antibiotic resistance in clinical isolates is driving a need to develop novel antibiotics to treat infection by this transmissible and highly virulent pathogen. Proteins required for viability, so called essential genes, are attractive potential therapeutic targets, however, confirmation of essentiality is problematic. For the first time, we report the development of a system that allows the rapid determination of Y. pestis gene essentiality through mutagenesis and inducible expression of a plasmid borne copy of the target gene. Using this approach, we have confirmed the uridine monophosphate kinase PyrH as an essential protein in Y. pestis. This methodology and the tools we have developed will allow the confirmation of other putative essential genes in this dangerous pathogen, and facilitate the identification of novel targets for antimicrobial development.
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Affiliation(s)
- D C Ford
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK.
| | - P M Ireland
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - H L Bullifent
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - R J Saint
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - E V McAlister
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - M Sarkar-Tyson
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - P C F Oyston
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
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Elgaml A, Higaki K, Miyoshi SI. Effects of temperature, growth phase and luxO-disruption on regulation systems of toxin production in Vibrio vulnificus strain L-180, a human clinical isolate. World J Microbiol Biotechnol 2013; 30:681-91. [DOI: 10.1007/s11274-013-1501-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Accepted: 09/18/2013] [Indexed: 12/19/2022]
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Doig P, Gorseth E, Nash T, Patten A, Gao N, Blackett C. Screening-based discovery of the first novel ATP competitive inhibitors of the Staphylococcus aureus essential enzyme UMP kinase. Biochem Biophys Res Commun 2013; 437:162-7. [PMID: 23806686 DOI: 10.1016/j.bbrc.2013.06.060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Accepted: 06/17/2013] [Indexed: 10/26/2022]
Abstract
UMP kinase (PyrH) is an essential enzyme found only in bacteria, making it ideal as a target for the discovery of antibacterials. To identify inhibitors of PyrH, an assay employing Staphylococcus aureus PyrH coupled to pyruvate kinase/lactate dehydrogenase was developed and was used to perform a high throughput screen. A validated aminopyrimidine series was identified from screening. Kinetic characterization of this aminopyrimidine indicated it was a competitive inhibitor of ATP. We have shown that HTS can be used to identify potential leads for this novel target, the first ATP competitive inhibitor of PyrH reported.
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Affiliation(s)
- Peter Doig
- Discovery Sciences, AstraZeneca R&D Boston, Waltham, MA 02451, United States.
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Identification of Burkholderia cenocepacia strain H111 virulence factors using nonmammalian infection hosts. Infect Immun 2012; 81:143-53. [PMID: 23090963 DOI: 10.1128/iai.00768-12] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Burkholderia cenocepacia H111, a strain isolated from a cystic fibrosis patient, has been shown to effectively kill the nematode Caenorhabditis elegans. We used the C. elegans model of infection to screen a mini-Tn5 mutant library of B. cenocepacia H111 for attenuated virulence. Of the approximately 5,500 B. cenocepacia H111 random mini-Tn5 insertion mutants that were screened, 22 showed attenuated virulence in C. elegans. Except for the quorum-sensing regulator cepR, none of the mutated genes coded for the biosynthesis of classical virulence factors such as extracellular proteases or siderophores. Instead, the mutants contained insertions in metabolic and regulatory genes. Mutants attenuated in virulence in the C. elegans infection model were also tested in the Drosophila melanogaster pricking model, and those also attenuated in this model were further tested in Galleria mellonella. Six of the 22 mutants were attenuated in D. melanogaster, and five of these were less pathogenic in the G. mellonella model. We show that genes encoding enzymes of the purine, pyrimidine, and shikimate biosynthesis pathways are critical for virulence in multiple host models of infection.
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Kim HU, Kim SY, Jeong H, Kim TY, Kim JJ, Choy HE, Yi KY, Rhee JH, Lee SY. Integrative genome-scale metabolic analysis of Vibrio vulnificus for drug targeting and discovery. Mol Syst Biol 2011; 7:460. [PMID: 21245845 PMCID: PMC3049409 DOI: 10.1038/msb.2010.115] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Accepted: 12/06/2010] [Indexed: 01/01/2023] Open
Abstract
Chromosome 1 of Vibrio vulnificus tends to contain larger portion of essential or housekeeping genes on the basis of the genomic analysis and gene knockout experiments performed in this study, while its chromosome 2 seems to have originated and evolved from a plasmid. The genome-scale metabolic network model of V. vulnificus was reconstructed based on databases and literature, and was used to identify 193 essential metabolites. Five essential metabolites finally selected after the filtering process are 2-amino-4-hydroxy-6-hydroxymethyl-7,8-dihydropteridine (AHHMP), D-glutamate (DGLU), 2,3-dihydrodipicolinate (DHDP), 1-deoxy-D-xylulose 5-phosphate (DX5P), and 4-aminobenzoate (PABA), which were predicted to be essential in V. vulnificus, absent in human, and are consumed by multiple reactions. Chemical analogs of the five essential metabolites were screened and a hit compound showing the minimal inhibitory concentration (MIC) of 2 μg/ml and the minimal bactericidal concentration (MBC) of 4 μg/ml against V. vulnificus was identified.
Discovering new antimicrobial targets and consequently new antimicrobials is important as drug resistance of pathogenic microorganisms is becoming an increasingly serious problem in human healthcare management (Fischbach and Walsh, 2009). There clearly exists a gap between genomic studies and drug discovery as the accumulation of knowledge on pathogens at genome level has not successfully transformed into the development of effective drugs (Mills, 2006; Payne et al, 2007). In this study, we dissected the genome of a microbial pathogen in detail, and subsequently developed a systems biological strategy of employing genome-scale metabolic modeling and simulation together with metabolite essentiality analysis for effective drug targeting and discovery. This strategy was used for identifying new drug targets in an opportunistic pathogen Vibrio vulnificus CMCP6 as a model. V. vulnificus is a Gram-negative halophilic bacterium that is found in estuarine waters, brackish ponds, or coastal areas, and its Biotype 1 is an opportunistic human pathogen that can attack immune-compromised patients, and causes primary septicemia, necrotized wound infections, and gastroenteritis. We previously found that many metabolic genes were specifically induced in vivo, suggesting that specific metabolic pathways are essential for in vivo survival and virulence of this pathogen (Kim et al, 2003; Lee et al, 2007). These results motivated us to carry out systems biological analysis of the genome and the metabolic network for new drug target discovery. V. vulnificus CMCP6 has two chromosomes. We first re-sequenced genomic regions assembled in low quality and low depth, and subsequently re-annotated the whole genome of V. vulnificus. Horizontal gene transfer was suspected to be responsible for the diversification of each chromosome of V. vulnificus, and the presence of metabolic genes was more biased to chromosome 1 than chromosome 2. Further studies on V. vulnificus genome revealed that chromosome 2 is more prone to diversification for better adaptation to the environment than its chromosome 1, while chromosome 1 tends to expand their genetic repertoire while maintaining the core genes at a constant level. Next, a genome-scale metabolic network VvuMBEL943 was reconstructed based on literature, databases and experiments for systematic studies on the metabolism of this pathogen and prediction of drug targets. The VvuMBEL943 model is composed of 943 reactions and 765 metabolites, and covers 673 genes. The model was validated by comparing its simulated cell growth phenotype obtained by constraints-based flux analysis with the V. vulnificus-specific experimental data previously reported in the literature. In this study, constraints-based flux analysis is an optimization-based simulation method that calculates intracellular fluxes under the specific genetic and environmental condition (Kim et al, 2008). As a result, 17 growth phenotypes were correctly predicted out of 18 cases, which demonstrate the validity of VvuMBEL943. The main objective of constructing VvuMBEL943 in this study is to predict potential drug targets by system-wide analysis of the metabolic network for the effective treatment of V. vulnificus. To achieve this goal, a set of drug target candidates was predicted by taking a metabolite-centric approach. Metabolite essentiality analysis is a concept recently introduced for the study of cellular robustness to complement conventional reaction or gene-centric approach (Kim et al, 2007b). Metabolite essentiality analysis observes changes in flux distribution by removing each metabolite from the in silico metabolic network. Hence, metabolite essentiality predicts essential metabolites whose absence causes cell death. By selecting essential metabolites, it is possible to directly screen only their structural analogs, which substantially reduces the number of chemical compounds to screen from the chemical compound library. As a result of implementing this approach, 193 metabolites were initially identified to be essential to the cell. These essential metabolites were then further filtered based on the predetermined criteria, mainly organism specificity and multiple connectivity associated with each metabolite, in order to reduce the number of initial target candidates towards identifying the most effective ones. Five essential metabolites finally selected are 2-amino-4-hydroxy-6-hydroxymethyl-7,8-dihydropteridine (AHHMP), D-glutamate (DGLU), 2,3-dihydrodipicolinate (DHDP), 1-deoxy-D-xylulose 5-phosphate (DX5P), and 4-aminobenzoate (PABA). Enzymes that consume these essential metabolites were experimentally verified to be essential, which indeed demonstrates the essentiality of these five metabolites. On the basis of the structural information of these five essential metabolites, whole-cell screening assay was performed using their analogs for possible antibacterial discovery. We screened 352 chemical analogs of the essential metabolites selected from the chemical compound library, and found a hit compound 24837, which shows the minimal inhibitory concentration (MIC) of 2 μg/ml and minimal bactericidal concentration (MBC) of 4 μg/ml, showing good antibacterial activity without further structural modification. Although this study demonstrates a proof-of-concept, the approaches and their rationale taken here should serve as a general strategy for discovering novel antibiotics and drugs based on systems-level analysis of metabolic networks. Although the genomes of many microbial pathogens have been studied to help identify effective drug targets and novel drugs, such efforts have not yet reached full fruition. In this study, we report a systems biological approach that efficiently utilizes genomic information for drug targeting and discovery, and apply this approach to the opportunistic pathogen Vibrio vulnificus CMCP6. First, we partially re-sequenced and fully re-annotated the V. vulnificus CMCP6 genome, and accordingly reconstructed its genome-scale metabolic network, VvuMBEL943. The validated network model was employed to systematically predict drug targets using the concept of metabolite essentiality, along with additional filtering criteria. Target genes encoding enzymes that interact with the five essential metabolites finally selected were experimentally validated. These five essential metabolites are critical to the survival of the cell, and hence were used to guide the cost-effective selection of chemical analogs, which were then screened for antimicrobial activity in a whole-cell assay. This approach is expected to help fill the existing gap between genomics and drug discovery.
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Affiliation(s)
- Hyun Uk Kim
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 program), Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
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Kim CM, Shin SH. Change ofVibrio vulnificusMetalloprotease VvpE Production by Temperature and Salinity. ACTA ACUST UNITED AC 2011. [DOI: 10.4167/jbv.2011.41.3.147] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Choon-Mee Kim
- Research Center for Resistant Cells, Chosun University Medical School, Gwangju, Korea
| | - Sung-Heui Shin
- Research Center for Resistant Cells, Chosun University Medical School, Gwangju, Korea
- Department of Microbiology, Chosun University Medical School, Gwangju, Korea
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Rostirolla DC, Breda A, Rosado LA, Palma MS, Basso LA, Santos DS. UMP kinase from Mycobacterium tuberculosis: Mode of action and allosteric interactions, and their likely role in pyrimidine metabolism regulation. Arch Biochem Biophys 2010; 505:202-12. [PMID: 21035424 DOI: 10.1016/j.abb.2010.10.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2010] [Revised: 10/21/2010] [Accepted: 10/21/2010] [Indexed: 11/28/2022]
Abstract
The pyrH-encoded uridine 5'-monophosphate kinase (UMPK) is involved in both de novo and salvage synthesis of DNA and RNA precursors. Here we describe Mycobacterium tuberculosis UMPK (MtUMPK) cloning and expression in Escherichia coli. N-terminal amino acid sequencing and electrospray ionization mass spectrometry analyses confirmed the identity of homogeneous MtUMPK. MtUMPK catalyzed the phosphorylation of UMP to UDP, using ATP-Mg²(+) as phosphate donor. Size exclusion chromatography showed that the protein is a homotetramer. Kinetic studies revealed that MtUMPK exhibits cooperative kinetics towards ATP and undergoes allosteric regulation. GTP and UTP are, respectively, positive and negative effectors, maintaining the balance of purine versus pyrimidine synthesis. Initial velocity studies and substrate(s) binding measured by isothermal titration calorimetry suggested that catalysis proceeds by a sequential ordered mechanism, in which ATP binds first followed by UMP binding, and release of products is random. As MtUMPK does not resemble its eukaryotic counterparts, specific inhibitors could be designed to be tested as antitubercular agents.
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Affiliation(s)
- Diana C Rostirolla
- Centro de Pesquisas em Biologia Molecular e Funcional, Instituto Nacional de Ciência e Tecnologia em Tuberculose, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil
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Zou YX, Mo ZL, Hao B, Ye XH, Guo DS, Zhang PJ. Screening of genes expressed in vivo after infection by Vibrio anguillarum M3. Lett Appl Microbiol 2010; 51:564-9. [PMID: 20849396 DOI: 10.1111/j.1472-765x.2010.02935.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS Genes uniquely expressed in vivo may contribute to the overall pathogenicity of an organism and are likely to serve as potential targets for the development of new vaccine. This study aims to screen the genes expressed in vivo after Vibrio anguillarum infection by in vivo-induced antigen technology (IVIAT). METHODS AND RESULTS The convalescent-phase sera were obtained from turbot (Scophthalmus maximus) survived after infection by the virulent V. anguillarum M3. The pooled sera were thoroughly adsorbed with M3 cells and Escherichia coli BL21 (DE3) cells. A genomic expression library of M3 was constructed and screened for the identification of immunogenic proteins by colony immunoblot analysis with the adsorbed sera. After three rounds of screening, 19 putative in vivo-induced (ivi) genes were obtained. These ivi genes were catalogued into four functional groups: regulator/signalling, metabolism, biological process and hypothetical proteins. Three ivi genes were insertion-mutated, and the growth and 50% lethal dose (LD(50) ) of these mutants were evaluated. CONCLUSIONS The identification of ivi genes in V. anguillarum M3 sheds light on understanding the bacterial pathogenesis and provides novel targets for the development of new vaccines and diagnostic reagents. SIGNIFICANCE AND IMPACT OF THE STUDY To the best of our knowledge, this is the first report describing in vivo-expressed genes of V. anguillarum using IVIAT. The screened ivi genes in this study could be new virulent factors and targets for the development of vaccine, which may have implications for the development of diagnostic regents.
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Affiliation(s)
- Y-X Zou
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
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Meyer P, Evrin C, Briozzo P, Joly N, Bârzu O, Gilles AM. Structural and functional characterization of Escherichia coli UMP kinase in complex with its allosteric regulator GTP. J Biol Chem 2008; 283:36011-8. [PMID: 18945668 DOI: 10.1074/jbc.m802614200] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Bacterial UMP kinases are essential enzymes involved in the multistep synthesis of UTP. They are hexamers regulated by GTP (allosteric activator) and UTP (inhibitor). We describe here the 2.8 angstroms crystal structure of Escherichia coli UMP kinase bound to GTP. The GTP-binding site, situated at 15 angstroms from the UMP-binding site and at 24 angstroms from the ATP-binding site, is delineated by two contiguous dimers. The overall structure, as compared with those bound to UMP, UDP, or UTP, shows a rearrangement of its quaternary structure: GTP induces an 11 degrees opening of the UMP kinase dimer, resulting in a tighter dimer-dimer interaction. A nucleotide-free UMP kinase dimer has an intermediate opening. Superposition of our structure with that of archaeal UMP kinases, which are also hexamers, shows that a loop appears to hamper any GTP binding in archeal enzymes. This would explain the absence of activating effect of GTP on this group of UMP kinases. Among GTP-binding residues, the Asp-93 is the most conserved in bacterial UMP kinases. In the previously published structures of E. coli UMP kinase, this residue was shown to be involved in hydrogen bonds between the subunits of a dimer. Its substitution by an alanine decreases the cooperativity for UTP binding and suppresses the reversal by GTP of UTP inhibition. This demonstrates that the previously described mutual exclusion of these two nucleotides is mediated by Asp-93.
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Affiliation(s)
- Philippe Meyer
- Laboratoire d'Enzymologie et de Biochimie Structurales, CNRS, UPR 3082, 91198 Gif-sur-Yvette Cedex, France
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Global gene expression as a function of the iron status of the bacterial cell: influence of differentially expressed genes in the virulence of the human pathogen Vibrio vulnificus. Infect Immun 2008; 76:4019-37. [PMID: 18573903 DOI: 10.1128/iai.00208-08] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Vibrio vulnificus multiplies rapidly in host tissues under iron-overloaded conditions. To understand the effects of iron in the physiology of this pathogen, we performed a genome-wide transcriptional analysis of V. vulnificus growing at three different iron concentrations, i.e., iron-limiting [Trypticase soy broth with 1.5% NaCl (TSBS) plus ethylenediamine-di-(o-hydroxyphenylacetic) acid (EDDA)], low-iron (1 microg Fe/ml; TSBS), and iron-rich (38 microg Fe/ml; TSBS plus ferric ammonium citrate) concentrations. A few genes were upregulated under the last two conditions, while several genes were expressed differentially under only one of them. A gene upregulated under both conditions encodes the outer membrane porin, OmpH, while others are related to the biosynthesis of amino sugars. An ompH mutant showed sensitivity to sodium dodecyl sulfate (SDS) and polymyxin B and also had a reduced competitive index compared with the wild type in the iron-overloaded mice. Under iron-limiting conditions, two of the TonB systems involved in vulnibactin transport were induced. These genes were essential for virulence in the iron-overloaded mice inoculated subcutaneously, underscoring the importance of active iron transport in infection, even under the high-iron conditions of this animal model. Furthermore, we demonstrated that a RyhB homologue is also essential for virulence in the iron-overloaded mouse. This novel information on the role of genes induced under iron limitation in the iron-overloaded mouse model and the finding of new genes with putative roles in virulence that are expressed only under iron-rich conditions shed light on the many strategies used by this pathogen to multiply rapidly in the susceptible host.
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