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Maurille C, Guérin F, Jehanne Q, Audemard-Verger A, Isnard C, Verdon R, Lehours P, Bonnet R, Giard JC, Le Hello S, Gravey F. Occurrence of in vivo carbapenem-resistant Campylobacter coli mediated by porA point mutation and overexpression of bla OXA-489 under meropenem treatment. Clin Microbiol Infect 2024:S1198-743X(24)00307-0. [PMID: 38969103 DOI: 10.1016/j.cmi.2024.06.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 06/07/2024] [Accepted: 06/28/2024] [Indexed: 07/07/2024]
Affiliation(s)
- Charles Maurille
- Normandie Univ, UNICAEN, CHU de Caen Normandie, Department of Infectious Diseases, 14000 Caen France; INSERM U1311 DynaMicURe, Normandie University, UNICAEN, UNIROUEN, 14000 Caen France.
| | - François Guérin
- Pontchaillou University Hospital, Department of Microbiology, 35000 Rennes France
| | - Quentin Jehanne
- French National Reference Center for Campylobacters and Helicobacters, Bordeaux Hospital University Center, Bordeaux France; Université de Bordeaux, UMR1312 Bordeaux Institute of Cancer, BRIC, 33076, Bordeaux, France
| | | | - Christophe Isnard
- INSERM U1311 DynaMicURe, Normandie University, UNICAEN, UNIROUEN, 14000 Caen France; Normandie Univ, UNICAEN, CHU de Caen Normandie, Department of Infectious Agents, Bacteriology, 14000 Caen France
| | - Renaud Verdon
- Normandie Univ, UNICAEN, CHU de Caen Normandie, Department of Infectious Diseases, 14000 Caen France; INSERM U1311 DynaMicURe, Normandie University, UNICAEN, UNIROUEN, 14000 Caen France
| | - Philippe Lehours
- French National Reference Center for Campylobacters and Helicobacters, Bordeaux Hospital University Center, Bordeaux France; Université de Bordeaux, UMR1312 Bordeaux Institute of Cancer, BRIC, 33076, Bordeaux, France
| | - Richard Bonnet
- Inserm U1071, USC-INRAe INRAE USC 1382, Microbes, Intestin, Inflammation et Susceptibilité de l'Hôte (M2iSH), Centre de Recherche en Nutrition Humaine Auvergne, Université Clermont Auvergne, Clermont-Ferrand, France
| | | | - Simon Le Hello
- INSERM U1311 DynaMicURe, Normandie University, UNICAEN, UNIROUEN, 14000 Caen France; Normandie Univ, UNICAEN, CHU de Caen Normandie, Department of Infectious Agents, Bacteriology, 14000 Caen France
| | - François Gravey
- INSERM U1311 DynaMicURe, Normandie University, UNICAEN, UNIROUEN, 14000 Caen France; Normandie Univ, UNICAEN, CHU de Caen Normandie, Department of Infectious Agents, Bacteriology, 14000 Caen France
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Rezayatmand H, Golestani N, Haghighat Hoseini AS, Mousavialmaleki E, Alem M, Farzane Yegane D. Gene expression profile of Campylobacter jejuni in response to macrolide antibiotics. Arch Microbiol 2024; 206:117. [PMID: 38393387 DOI: 10.1007/s00203-024-03849-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 01/06/2024] [Accepted: 01/16/2024] [Indexed: 02/25/2024]
Abstract
Campylobacter jejuni is a foodborne pathogen that causes gastroenteritis in humans and has developed resistance to various antibiotics. The primary objective of this research was to examine the network of antibiotic resistance in C. jejuni. The study involved the wild and antibiotic-resistant strains placed in the presence and absence of antibiotics to review their gene expression profiles in response to ciprofloxacin via microarray. Differentially expressed genes (DEGs) analysis and Protein-Protein Interaction (PPI) Network studies were performed for these genes. The results showed that the resistance network of C. jejuni is modular, with different genes involved in bacterial motility, capsule synthesis, efflux, and amino acid and sugar synthesis. Antibiotic treatment resulted in the down-regulation of cluster genes related to translation, flagellum formation, and chemotaxis. In contrast, cluster genes involved in homeostasis, capsule formation, and cation efflux were up-regulated. The study also found that macrolide antibiotics inhibit the progression of C. jejuni infection by inactivating topoisomerase enzymes and increasing the activity of epimerase enzymes, trying to compensate for the effect of DNA twisting. Then, the bacterium limits the movement to conserve energy. Identifying the antibiotic resistance network in C. jejuni can aid in developing drugs to combat these bacteria. Genes involved in cell division, capsule formation, and substance transport may be potential targets for inhibitory drugs. Future research must be directed toward comprehending the underlying mechanisms contributing to the modularity of antibiotic resistance and developing strategies to disrupt and mitigate the growing threat of antibiotic resistance effectively.
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Affiliation(s)
- Hamed Rezayatmand
- Department of Pharmacy and Technology of Organic Substances, Industrial Pharmacy, Ukrainian State Chemical Technology University, Dnipro, Ukraine
| | - Nafiseh Golestani
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | | | - Elaheh Mousavialmaleki
- Pharmaceutical Science Research Center, Medicinal Chemistry Department, Faculty of Pharmacy, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Mahsa Alem
- Department of Microbiology, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran.
| | - Donya Farzane Yegane
- Department of Pharmacognosy and Pharmaceutical Biotechnology, Faculty of Pharmacy, Lorestan University of Medical Sciences, Khorramabad, Iran
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Zarske M, Luu HQ, Deneke C, Knüver MT, Thieck M, Hoang HTT, Bretschneider N, Pham NT, Huber I, Stingl K. Identification of knowledge gaps in whole-genome sequence analysis of multi-resistant thermotolerant Campylobacter spp. BMC Genomics 2024; 25:156. [PMID: 38331708 PMCID: PMC10851486 DOI: 10.1186/s12864-024-10014-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Accepted: 01/14/2024] [Indexed: 02/10/2024] Open
Abstract
BACKGROUND Campylobacter spp. is the most frequent cause of bacterial food-borne gastroenteritis and a high priority antibiotic resistant bacterium according to the World Health Organization (WHO). European monitoring of thermotolerant Campylobacter spp. does not reflect the global burden of resistances already circulating within the bacterial population worldwide. METHODS We systematically compared whole genome sequencing with comprehensive phenotypic antimicrobial susceptibility, analyzing 494 thermotolerant Campylobacter poultry isolates from Vietnam and Germany. Any discrepancy was checked by repeating the wet lab and improving the dry lab part. Selected isolates were additionally analyzed via long-read Oxford Nanopore technology, leading to closed chromosomes and plasmids. RESULTS Overall, 22 different resistance genes and gene variants (e. g. erm(B), aph(3')-IIIa, aph(2'')-If, catA, lnu(C), blaOXA, sat4) and point mutations in three distinct genes (gyrA, 23S rRNA, rpsL) associated with AMR were present in the Campylobacter isolates. Two AMR genes were missing in the database and one falsely associated with resistance. Bioinformatic analysis based on short-read data partly failed to identify tet(O) and aadE, when the genes were present as duplicate or homologous gene variants. Intriguingly, isolates also contained different determinants, redundantly conferring resistance to chloramphenicol, gentamicin, kanamycin, lincomycin and streptomycin. We found a novel tet(W) in tetracycline sensitive strains, harboring point mutations. Furthermore, analysis based on assemblies from short-read data was impaired to identify full length phase variable aad9, due to variations of the poly-C tract within the gene. The genetic determinant responsible for gentamicin resistance of one isolate from Germany could not be identified. GyrT86I, presenting the main determinant for (fluoro-)quinolone resistance led to a rare atypical phenotype of ciprofloxacin resistance but nalidixic acid sensitivity. Long-read sequencing predicted AMR genes were mainly located on the chromosome, and rarely on plasmids. Predictions from long- and short-read sequencing, respectively, often differed. AMR genes were often organized in multidrug resistance islands (MDRI) and partially located in proximity to transposase genes, suggesting main mobilization of resistance determinants is via natural transformation and transposition in Campylobacter. CONCLUSIONS The results of this study suggest that there is frequent resistance gene duplication, mosaicism, and mutation leading to gene variation and truncation in Campylobacter strains that have not been reported in previous studies and are missing from databases. Furthermore, there is a need for deciphering yet unknown resistance mechanisms and resistance spread in thermotolerant Campylobacter spp. that may pose a challenge to global food safety.
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Affiliation(s)
- Michael Zarske
- Department of Biological Safety, Federal Institute for Risk Assessment (BfR), Diedersdorfer Weg 1, Berlin, D-12277, Germany
| | - Huong Quynh Luu
- National Institute of Veterinary Research (NIVR), 86 Truong Chinh Street, Hanoi, Dong Da District, Vietnam
| | - Carlus Deneke
- Department of Biological Safety, Federal Institute for Risk Assessment (BfR), Diedersdorfer Weg 1, Berlin, D-12277, Germany
| | - Marie-Theres Knüver
- Department of Biological Safety, Federal Institute for Risk Assessment (BfR), Diedersdorfer Weg 1, Berlin, D-12277, Germany
| | - Maja Thieck
- Department of Biological Safety, Federal Institute for Risk Assessment (BfR), Diedersdorfer Weg 1, Berlin, D-12277, Germany
| | - Ha Thi Thu Hoang
- Department of Bacteriology, National Institute of Hygiene and Epidemiology (NIHE), 1 Yersin Street, Hanoi, Trung District, Vietnam
| | - Nancy Bretschneider
- Department of Molecular Biology and Gene Technology, Bavarian Health and Food Safety Authority, Oberschleissheim, D-85764, Germany
| | - Ngoc Thi Pham
- National Institute of Veterinary Research (NIVR), 86 Truong Chinh Street, Hanoi, Dong Da District, Vietnam
| | - Ingrid Huber
- Department of Molecular Biology and Gene Technology, Bavarian Health and Food Safety Authority, Oberschleissheim, D-85764, Germany
| | - Kerstin Stingl
- Department of Biological Safety, Federal Institute for Risk Assessment (BfR), Diedersdorfer Weg 1, Berlin, D-12277, Germany.
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Nunes A, Oleastro M, Alves F, Liassine N, Lowe DM, Benejat L, Ducounau A, Jehanne Q, Borges V, Gomes JP, Godbole G, Philippe L. Recurrent Campylobacter jejuni Infections with In Vivo Selection of Resistance to Macrolides and Carbapenems: Molecular Characterization of Resistance Determinants. Microbiol Spectr 2023; 11:e0107023. [PMID: 37358443 PMCID: PMC10434052 DOI: 10.1128/spectrum.01070-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 05/24/2023] [Indexed: 06/27/2023] Open
Abstract
We present two independent cases of recurrent multidrug-resistant Campylobacter jejuni infection in immunocompromised hosts and the clinical challenges encountered due to the development of high-level carbapenem resistance. The mechanisms associated with this unusual resistance for Campylobacters were characterized. Initial macrolide and carbapenem-susceptible strains acquired resistance to erythromycin (MIC > 256mg/L), ertapenem (MIC > 32mg/L), and meropenem (MIC > 32mg/L) during treatment. Carbapenem-resistant isolates developed an in-frame insertion resulting in an extra Asp residue in the major outer membrane protein PorA, within the extracellular loop L3 that connects β-strands 5 and 6 and forms a constriction zone involved in Ca2+ binding. The isolates presenting the highest MIC to ertapenem exhibited an extra nonsynonymous mutation (G167A|Gly56Asp) at PorA's extracellular loop L1. IMPORTANCE Carbapenem susceptibility patterns suggest drug impermeability, related to either insertion and/or single nucleotide polymorphism (SNP) within porA. Similar molecular events occurring in two independent cases support the association of these mechanisms with carbapenem resistance in Campylobacter spp.
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Affiliation(s)
- Alexandra Nunes
- Infectious Diseases Department, National Institute of Health Dr. Ricardo Jorge (INSA), Lisbon, Portugal
- Faculty of Veterinary Medicine, Lusófona University, Lisbon, Portugal
| | - Mónica Oleastro
- Infectious Diseases Department, National Institute of Health Dr. Ricardo Jorge (INSA), Lisbon, Portugal
| | - Frederico Alves
- Infectious Diseases Department, National Institute of Health Dr. Ricardo Jorge (INSA), Lisbon, Portugal
| | | | | | - Lucie Benejat
- French National Reference Centre for Campylobacters and Helicobacters, Bordeaux Hospital University Centre, Bordeaux, France
| | - Astrid Ducounau
- French National Reference Centre for Campylobacters and Helicobacters, Bordeaux Hospital University Centre, Bordeaux, France
| | - Quentin Jehanne
- French National Reference Centre for Campylobacters and Helicobacters, Bordeaux Hospital University Centre, Bordeaux, France
| | - Vítor Borges
- Infectious Diseases Department, National Institute of Health Dr. Ricardo Jorge (INSA), Lisbon, Portugal
| | - João Paulo Gomes
- Infectious Diseases Department, National Institute of Health Dr. Ricardo Jorge (INSA), Lisbon, Portugal
- Faculty of Veterinary Medicine, Lusófona University, Lisbon, Portugal
| | | | - Lehours Philippe
- French National Reference Centre for Campylobacters and Helicobacters, Bordeaux Hospital University Centre, Bordeaux, France
- University of Bordeaux, INSERM, Bordeaux Institute of Oncology, Bordeaux, France
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van der Graaf-van Bloois L, Duim B, Looft T, Veldman KT, Zomer AL, Wagenaar JA. Antimicrobial resistance in Campylobacter fetus: emergence and genomic evolution. Microb Genom 2023; 9. [PMID: 36862577 PMCID: PMC10132061 DOI: 10.1099/mgen.0.000934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023] Open
Abstract
Campylobacter fetus is a pathogen, which is primarily associated with fertility problems in sheep and cattle. In humans, it can cause severe infections that require antimicrobial treatment. However, knowledge on the development of antimicrobial resistance in C. fetus is limited. Moreover, the lack of epidemiological cut-off values (ECOFFs) and clinical breakpoints for C. fetus hinders consistent reporting about wild-type and non-wild-type susceptibility. The aim of this study was to determine the phenotypic susceptibility pattern of C. fetus and to determine the C. fetus resistome [the collection of all antimicrobial resistance genes (ARGs) and their precursors] to describe the genomic basis of antimicrobial resistance in C. fetus isolates over time. Whole-genome sequences of 295 C. fetus isolates, including isolates that were isolated in the period 1939 till the mid 1940s, before the usage of non-synthetic antimicrobials, were analysed for the presence of resistance markers, and phenotypic antimicrobial susceptibility was obtained for a selection of 47 isolates. C. fetus subspecies fetus (Cff) isolates showed multiple phenotypic antimicrobial resistances compared to C. fetus subspecies venerealis (Cfv) isolates that were only intrinsic resistant to nalidixic acid and trimethoprim. Cff isolates showed elevated minimal inhibitory concentrations for cefotaxime and cefquinome that were observed in isolates from 1943 onwards, and Cff isolates contained gyrA substitutions, which conferred resistance to ciprofloxacin. Resistances to aminoglycosides, tetracycline and phenicols were linked to acquired ARGs on mobile genetic elements. A plasmid-derived tet(O) gene in a bovine Cff isolate in 1999 was the first mobile genetic element observed, followed by detection of mobile elements containing tet(O)-aph(3')-III and tet(44)-ant(6)-Ib genes, and a plasmid from a single human isolate in 2003, carrying aph(3')-III-ant(6)-Ib and a chloramphenicol resistance gene (cat). The presence of ARGs in multiple mobile elements distributed among different Cff lineages highlights the risk for spread and further emergence of AMR in C. fetus. Surveillance for these resistances requires the establishment of ECOFFs for C. fetus.
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Affiliation(s)
- Linda van der Graaf-van Bloois
- Department Biomolecular Health Sciences, Division Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands.,WHO Collaborating Centre for Reference and Research on Campylobacter and Antimicrobial Resistance from a One Health Perspective / WOAH Reference Laboratory for Campylobacteriosis, Utrecht/Lelystad, Netherlands
| | - Birgitta Duim
- Department Biomolecular Health Sciences, Division Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands.,WHO Collaborating Centre for Reference and Research on Campylobacter and Antimicrobial Resistance from a One Health Perspective / WOAH Reference Laboratory for Campylobacteriosis, Utrecht/Lelystad, Netherlands
| | - Torey Looft
- Food Safety and Enteric Pathogens Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, IA, USA
| | - Kees T Veldman
- Wageningen Bioveterinary Research, Lelystad, Netherlands
| | - Aldert L Zomer
- Department Biomolecular Health Sciences, Division Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands.,WHO Collaborating Centre for Reference and Research on Campylobacter and Antimicrobial Resistance from a One Health Perspective / WOAH Reference Laboratory for Campylobacteriosis, Utrecht/Lelystad, Netherlands
| | - Jaap A Wagenaar
- Department Biomolecular Health Sciences, Division Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands.,WHO Collaborating Centre for Reference and Research on Campylobacter and Antimicrobial Resistance from a One Health Perspective / WOAH Reference Laboratory for Campylobacteriosis, Utrecht/Lelystad, Netherlands.,Wageningen Bioveterinary Research, Lelystad, Netherlands
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Campylobacter jejuni from Slaughter Age Broiler Chickens: Genetic Characterization, Virulence, and Antimicrobial Resistance Genes. Int J Microbiol 2022; 2022:1713213. [PMID: 35634271 PMCID: PMC9135541 DOI: 10.1155/2022/1713213] [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: 03/31/2022] [Revised: 04/26/2022] [Accepted: 05/05/2022] [Indexed: 11/17/2022] Open
Abstract
Campylobacter jejuni is a major cause of food-borne human gastroenteritis worldwide and is designated as a high priority antimicrobial-resistant pathogen by the World Health Organization (WHO). In this study, a total of 26 C. jejuni isolates from broiler chickens were screened for the presence of virulence and antimicrobial resistance genes by PCR. As a result, the study detected 11/26 (42.3%), 9/26 (34.6%), 8/26 (30.8%), 7/26 (26.9%), 6/26 (23.1%), and 6/26 (23.1%) of cdtC, pldA, cdtB, cdtA, cadF, and ciaB virulence genes, respectively, with seven of the isolates carrying more than two virulence genes. The majority of the isolates n = 25 (96.1%) were resistant to nalidixic acid, followed by n = 21 (80.7%), n = 22 (84.6%), and n = 5 (19.2%) for tetracycline, erythromycin, and ciprofloxacin, respectively. Most isolates were harboring catI (n = 16; 84.2%), catII (n = 15; 78.9%), catIII (n = 10; 52.6%), catIV (n = 2; 10.5%), floR (n = 10; 52.6%), ermB (n = 14; 73.7%), tetO (n = 13; 68.4%), tetA (n = 9; 47.4%), mcr-4 (n = 8; 42.1%), and ampC (n = 2; 10.5%). Meanwhile, mcr-1, mcr-2, mcr-3, mcr-5, tet(X), tet(P), and tet(W) genes were not detected in all isolates. Class I and Class II integrons were detected in 92.3% (n = 24) and 65.4% (n = 17) isolates, respectively. About 31% (8 of the 26 isolates) isolates were carrying more than two resistance genes. According to our knowledge, this is the first study to detect class II integrons in Campylobacter spp. (C. jejuni). The high prevalence of cdtA, cdtB, cdtC, cadF, pldA, and ciaB genes and antibiotic resistance genes in C. jejuni in this study indicates the pathogenic potential of these isolates. Majority of the isolates demonstrated resistance to nalidixic acid, tetracycline (tet), and erythromycin (ermB), which are the drugs of choice for treating Campylobacter infections. Therefore, these findings highlight the importance of implementing an efficient strategy to control Campylobacter in chickens and to reduce antimicrobial use in the poultry industry, which will help to prevent the spread of infections to humans.
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You Y, Thorell K, He L, Yahara K, Yamaoka Y, Cha JH, Murakami K, Katsura Y, Kobayashi I, Falush D, Zhang J. Genomic differentiation within East Asian Helicobacter pylori. Microb Genom 2022; 8. [PMID: 35188454 PMCID: PMC8942036 DOI: 10.1099/mgen.0.000676] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The East Asian region, including China, Japan and Korea, accounts for half of gastric cancer deaths. However, different areas have contrasting gastric cancer incidences and the population structure of Helicobacter pylori in this ethnically diverse region is yet unknown. We aimed to investigate genomic differences in H. pylori between these areas to identify sequence polymorphisms associated with increased cancer risk. We analysed 381 H. pylori genomes collected from different areas of the three countries using phylogenetic and population genetic tools to characterize population differentiation. The functional consequences of SNPs with a highest fixation index (Fst) between subpopulations were examined by mapping amino acid changes on 3D protein structure, solved or modelled. Overall, 329/381 genomes belonged to the previously identified hspEAsia population indicating that import of bacteria from other regions of the world has been uncommon. Seven subregional clusters were found within hspEAsia, related to subpopulations with various ethnicities, geographies and gastric cancer risks. Subpopulation-specific amino acid changes were found in multidrug exporters (hefC), transporters (frpB-4), outer membrane proteins (hopI) and several genes involved in host interaction, such as a catalase site, involved in H2O2 entrance, and a flagellin site mimicking host glycosylation. Several of the top hits, including frpB-4, hefC, alpB/hopB and hofC, have been found to be differentiated within the Americas in previous studies, indicating that a handful of genes may be key to local geographic adaptation. H. pylori within East Asia are not homogeneous but have become differentiated geographically at multiple loci that might have facilitated adaptation to local conditions and hosts. This has important implications for further evaluation of these changes in relation to the varying gastric cancer incidence between geographical areas in this region.
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Affiliation(s)
- Yuanhai You
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, PR China
| | - Kaisa Thorell
- Department of Clinical Microbiology, Sahlgrenska University Hospital, Västra Götaland 12 Region, Gothenburg, Sweden
- Department of Infectious Diseases, Sahlgrenska Academy, University of Gothenburg, Sweden
| | - Lihua He
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, PR China
| | - Koji Yahara
- Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Oita, Japan
| | - Jeong-Heon Cha
- Department of Oral Biology, BK21 Plus Project, Yonsei University College of Dentistry, Seoul, Republic of Korea
| | - Kazunari Murakami
- Department of Gastroenterology, Faculty of Medicine, Oita University, Oita, Japan
| | - Yukako Katsura
- Primate Research Institute, Kyoto University, Inuyama, Japan
| | - Ichizo Kobayashi
- Department of Computational Biology and Medical Sciences (formerly Department of Medical Genome Sciences), Graduate School of Frontier Sciences, University of Tokyo, Tokyo, Japan
- Department of Infectious Diseases, Kyorin University School of Medicine, Mitaka-shi, Tokyo, Japan
- I2BC, University of Paris-Saclay, Gif-sur-Yvette, France
- Research Center for Micro-Nano Technology, Hosei University, Koganei-shi, Tokyo, Japan
- Institute of Medical Science, University of Tokyo, Minato-ku, Tokyo, Japan
| | - Daniel Falush
- The Center for Microbes, Development and Health, Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, PR China
| | - Jianzhong Zhang
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, PR China
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Forson AO, Adjei DN, Olu-Taiwo M, Quarchie MN, Asmah HR. Characterization of Campylobacter associated gastric enteritis among patients with Human Immunodeficiency Virus (HIV) in a hospital in Accra, Ghana. PLoS One 2020; 15:e0240242. [PMID: 33057408 PMCID: PMC7561167 DOI: 10.1371/journal.pone.0240242] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 09/22/2020] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Campylobacter infections in HIV positive patients often present with substantial mortality and morbidity when compared to HIV negative patients. AIM This study assessed the prevalence of Campylobacter, antibiotic resistance phenotypes and genetic factors, and risk of Campylobacter infection associated with living in close proximity to domestic animals in HIV patients with gastric enteritis at Korle-Bu Teaching Hospital, Accra, Ghana. METHODS Resistance to different antibiotics was assessed with Kirby-Bauer disk diffusion method. In addition, all the Campylobacter isolates were tested for ampicillin (blaOXA-61), erythromycin (aph-3-1), tetracycline tet(O), streptomycin (aadE), and the energy-dependent multi-drug efflux pump (cmeB) resistance genes using multiplex polymerase chain reaction. RESULTS Out of a total of 140 (97 females and 43 males) tested patients, 71 (50.7%) patients were positive for Campylobacter coli. Female patients aged within 31-40 years (31.6%) and 41-50 years (31.6%) had high frequency of Campylobacter infection. Most of the infected patients lived in close proximity to chickens (53.5%), however, some patients (14.1%) lived in close proximity to goats. Phenotypic resistance evaluation revealed widespread resistance to ampicillin (100%), tetracycline (100%), ciprofloxacin (71.8%), erythromycin (69%), and gentamicin (49.3%). However, limited no of isolates contained blaOXA-61 (1.41%), cmeB (7.0%) and tet(O (7.0%) resistance genes. CONCLUSION HIV patients with gastric enteritis were infected with resistant Campylobacter coli. Further studies are required to examine correlation of infected patients with C. coli and risk of living in close proximity to poultry birds. There is the need for routine investigation of Campylobacter in patients with gastroenteritis in order to assist in the development of strategies for combating diseases involving resistant zoonotic bacteria strains.
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Affiliation(s)
- Akua Obeng Forson
- Department of Medical Laboratory Science, School of Biomedical and Allied Health Sciences, College of Health Sciences, University of Ghana, Legon, Ghana
| | - David Nana Adjei
- Department of Medical Laboratory Science, School of Biomedical and Allied Health Sciences, College of Health Sciences, University of Ghana, Legon, Ghana
| | - Michael Olu-Taiwo
- Department of Medical Laboratory Science, School of Biomedical and Allied Health Sciences, College of Health Sciences, University of Ghana, Legon, Ghana
| | - Marjorie Ntiwaa Quarchie
- Department of Medical Laboratory Science, School of Biomedical and Allied Health Sciences, College of Health Sciences, University of Ghana, Legon, Ghana
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The Rho-Independent Transcription Terminator for the porA Gene Enhances Expression of the Major Outer Membrane Protein and Campylobacter jejuni Virulence in Abortion Induction. Infect Immun 2019; 87:IAI.00687-19. [PMID: 31570559 DOI: 10.1128/iai.00687-19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 09/23/2019] [Indexed: 01/22/2023] Open
Abstract
Campylobacter jejuni is a leading cause of foodborne illnesses worldwide. Its porA gene encodes the major outer membrane protein (MOMP) that is abundantly expressed and has important physiological functions, including a key role in systemic infection and abortion induction in pregnant animals. Despite the importance of porA in C. jejuni pathogenesis, mechanisms modulating its expression levels remain elusive. At the 3' end of the porA transcript, there is a Rho-independent transcription terminator (named T porA in this study). Whether T porA affects the expression and function of MOMP remains unknown and is investigated in this study. Green fluorescent protein (GFP) fusion constructs with the porA promoter at the 5' end and an intact T porA or no T porA at the 3' end of the gfp coding sequence revealed that both the transcript level of gfp and its fluorescence signals were more than 2-fold higher in the construct with T porA than in the one without T porA Real-time quantitative PCR (qRT-PCR) analysis of the porA mRNA and immunoblot detection of MOMP in C. jejuni showed that disruption of T porA significantly reduced the porA transcript level and the expression of MOMP. An mRNA decay assay demonstrated that disruption of T porA resulted in a shortened transcript half-life of the upstream gfp or porA gene, indicating that T porA enhances mRNA stability. In the guinea pig model, the C. jejuni construct with an interrupted T porA was significantly attenuated in abortion induction. Together, these results indicate that T porA enhances the expression level of MOMP by stabilizing its mRNA and influences the virulence of C. jejuni.
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Yang Y, Feye KM, Shi Z, Pavlidis HO, Kogut M, J Ashworth A, Ricke SC. A Historical Review on Antibiotic Resistance of Foodborne Campylobacter. Front Microbiol 2019; 10:1509. [PMID: 31402900 PMCID: PMC6676416 DOI: 10.3389/fmicb.2019.01509] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 06/17/2019] [Indexed: 01/06/2023] Open
Abstract
Campylobacter is one of the most commonly reported foodborne human bacterial gastrointestinal pathogens. Campylobacter is the etiological agent of campylobacteriosis, which is generally a self-limited illness and therefore does not require treatment. However, when patients are immunocompromised or have other co-morbidities, antimicrobial treatment may be necessary for clinical treatment of campylobacteriosis, macrolides and fluoroquinolones are the drugs of choices. However, the increase in antimicrobial resistance of Campylobacter to clinically important antibiotics may become insurmountable. Because of the transmission between poultry and humans, the poultry industry must now allocate resources to address the problem by reducing Campylobacter as well as antimicrobial use, which may reduce resistance. This review will focus on the incidence of antibiotic-resistant Campylobacter in poultry, the clinical consequences of this resistance, and the mechanisms of antibiotic resistance associated with Campylobacter.
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Affiliation(s)
- Yichao Yang
- Department of Poultry Science, University of Arkansas Fayetteville, Fayetteville, AR, United States
| | - Kristina M Feye
- Southern Plains Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture, College Station, TX, United States
| | - Zhaohao Shi
- Center of Food Safety, Department of Food Science, University of Arkansas, Fayetteville, AR, United States
| | | | - Michael Kogut
- Southern Plains Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture, College Station, TX, United States
| | - Amanda J Ashworth
- Poultry Production and Product Safety Research Unit (USDA-ARS), Fayetteville, AR, United States
| | - Steven C Ricke
- Southern Plains Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture, College Station, TX, United States
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11
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Abstract
Campylobacter is a major foodborne pathogen and has become increasingly resistant to clinically important antimicrobials. To cope with the selection pressure from antimicrobial use in both veterinary and human medicine, Campylobacter has developed multiple mechanisms for antibiotic resistance, including modification or mutation of antimicrobial targets, modification or inactivation of antibiotics, and reduced drug accumulation by drug efflux pumps. Some of these mechanisms confer resistance to a specific class of antimicrobials, while others give rise to multidrug resistance. Notably, new antibiotic resistance mechanisms continuously emerge in Campylobacter, and some examples include the recently discovered multidrug resistance genomic islands harboring multiple genes involved in the resistance to aminoglycosides and macrolides, a novel Cfr(C) conferring resistance to phenicols and other drugs, and a potent multidrug efflux pump CmeABC variant (RE-CmeABC) that shows a significantly enhanced function in multidrug resistance and is associated with exceedingly high-level resistance to fluoroquinolones. These newly emerged resistance mechanisms are horizontally transferable and greatly facilitate the adaptation of Campylobacter in the food-producing environments where antibiotics are frequently used. In this article, we will discuss how Campylobacter resists the action of various classes of antimicrobials, with an emphasis on newly discovered mechanisms.
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Dhanasekar NN, Aliouane S, Winterhalter M, Pagès JM, Bolla JM. Peptide translocation across MOMP, the major outer membrane channel from Campylobacter jejuni. Biochem Biophys Rep 2017; 11:79-83. [PMID: 28955771 PMCID: PMC5614690 DOI: 10.1016/j.bbrep.2017.06.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 04/12/2017] [Accepted: 06/22/2017] [Indexed: 11/17/2022] Open
Abstract
Here we report on translocation of short poly-arginines across the MOMP porin, the major outer membrane protein in the cell wall of Campylobacter jejuni. MOMP was purified to homogeneity from a pathogenic strain of C. jejuni. Its reconstitution in lipid membranes and measuring the ion-current revealed two main distinct populations of protein channels which we interpreted as mono and trimers. Addition of poly-arginines causes concentration and voltage dependent ion-current fluctuations. Increasing the transmembrane potential decreases the residence time of the peptide inside the channel indicating successful translocation. We conclude that poly-arginines can cross the outer membrane of Campylobacter through the MOMP channel. Translocation of short poly-arginines across the MOMP channel has been determined. Penta-arginine and Hepta-arginine translocate across the MOMP channel. Voltage dependent kinetics to distinguish binding from translocation.
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Affiliation(s)
| | | | - Mathias Winterhalter
- Department of Life Sciences and Chemistry, Jacobs University Bremen, 28719 Bremen, Germany
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13
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Ferrara LGM, Wallat GD, Moynié L, Dhanasekar NN, Aliouane S, Acosta-Gutiérrez S, Pagès JM, Bolla JM, Winterhalter M, Ceccarelli M, Naismith JH. MOMP from Campylobacter jejuni Is a Trimer of 18-Stranded β-Barrel Monomers with a Ca 2+ Ion Bound at the Constriction Zone. J Mol Biol 2016; 428:4528-4543. [PMID: 27693650 PMCID: PMC5090048 DOI: 10.1016/j.jmb.2016.09.021] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 09/26/2016] [Accepted: 09/26/2016] [Indexed: 11/11/2022]
Abstract
The Gram-negative organism Campylobacter jejuni is the major cause of food poisoning. Unlike Escherichia coli, which has two major porins, OmpC and OmpF, C. jejuni has one, termed major outer membrane protein (MOMP) through which nutrients and antibiotics transit. We report the 2.1-Å crystal structure of C. jejuni MOMP expressed in E. coli and a lower resolution but otherwise identical structure purified directly from C. jejuni. The 2.1-Å resolution structure of recombinant MOMP showed that although the protein has timeric arrangement similar to OmpC, it is an 18-stranded, not 16-stranded, β-barrel. The structure has identified a Ca2 + bound at the constriction zone, which is functionally significant as suggested by molecular dynamics and single-channel experiments. The water-filled channel of MOMP has a narrow constriction zone, and single-molecule studies show a monomeric conductivity of 0.7 ± 0.2 nS and a trimeric conductance of 2.2 ± 0.2 nS. The ion neutralizes negative charges at the constriction zone, reducing the transverse electric field and reversing ion selectivity. Modeling of the transit of ciprofloxacin, an antibiotic of choice for treating Campylobacter infection, through the pore of MOMP reveals a trajectory that is dependent upon the presence metal ion. The crystal structure of MOMP, the general diffusion porin of Campylobacter, has been determined. The protein is an 18-stranded β-barrel that is different than the 16-stranded OmpC and OmpF proteins from E. coli, but like them, MOMP is trimeric. The protein has a central pore size and conductivity intermediate between OmpC and OmpF. A Ca2 + ion bound at the constriction zone influences the biophysical properties of porin. The trajectory of the transit of the antibiotic ciprofloxacin through the pore is dependent on the presence of a metal ion.
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Affiliation(s)
- Luana G M Ferrara
- Biomedical Sciences Research Complex, University of St Andrews, 09042 St Andrews, UK
| | - Gregor D Wallat
- Biomedical Sciences Research Complex, University of St Andrews, 09042 St Andrews, UK
| | - Lucile Moynié
- Biomedical Sciences Research Complex, University of St Andrews, 09042 St Andrews, UK
| | - Naresh N Dhanasekar
- Department of Life Sciences and Chemistry, Jacobs University Bremen, 28719 Bremen, Germany
| | | | - Silvia Acosta-Gutiérrez
- Department of Physics, University of Cagliari, Cittadella Universitaria Monserrato, S.P8-km 0.700, 09042 Monserrato, Cagliari (CA), Italy
| | | | | | - Mathias Winterhalter
- Department of Life Sciences and Chemistry, Jacobs University Bremen, 28719 Bremen, Germany
| | - Matteo Ceccarelli
- Department of Physics, University of Cagliari, Cittadella Universitaria Monserrato, S.P8-km 0.700, 09042 Monserrato, Cagliari (CA), Italy
| | - James H Naismith
- Biomedical Sciences Research Complex, University of St Andrews, 09042 St Andrews, UK; State Key Laboratory of Biotherapy, Sichuan University, Chengdu 610041, China.
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14
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Li XZ, Plésiat P, Nikaido H. The challenge of efflux-mediated antibiotic resistance in Gram-negative bacteria. Clin Microbiol Rev 2015; 28:337-418. [PMID: 25788514 PMCID: PMC4402952 DOI: 10.1128/cmr.00117-14] [Citation(s) in RCA: 899] [Impact Index Per Article: 99.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The global emergence of multidrug-resistant Gram-negative bacteria is a growing threat to antibiotic therapy. The chromosomally encoded drug efflux mechanisms that are ubiquitous in these bacteria greatly contribute to antibiotic resistance and present a major challenge for antibiotic development. Multidrug pumps, particularly those represented by the clinically relevant AcrAB-TolC and Mex pumps of the resistance-nodulation-division (RND) superfamily, not only mediate intrinsic and acquired multidrug resistance (MDR) but also are involved in other functions, including the bacterial stress response and pathogenicity. Additionally, efflux pumps interact synergistically with other resistance mechanisms (e.g., with the outer membrane permeability barrier) to increase resistance levels. Since the discovery of RND pumps in the early 1990s, remarkable scientific and technological advances have allowed for an in-depth understanding of the structural and biochemical basis, substrate profiles, molecular regulation, and inhibition of MDR pumps. However, the development of clinically useful efflux pump inhibitors and/or new antibiotics that can bypass pump effects continues to be a challenge. Plasmid-borne efflux pump genes (including those for RND pumps) have increasingly been identified. This article highlights the recent progress obtained for organisms of clinical significance, together with methodological considerations for the characterization of MDR pumps.
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Affiliation(s)
- Xian-Zhi Li
- Human Safety Division, Veterinary Drugs Directorate, Health Products and Food Branch, Health Canada, Ottawa, Ontario, Canada
| | - Patrick Plésiat
- Laboratoire de Bactériologie, Faculté de Médecine-Pharmacie, Centre Hospitalier Régional Universitaire, Université de Franche-Comté, Besançon, France
| | - Hiroshi Nikaido
- Department of Molecular and Cell Biology, University of California, Berkeley, California, USA
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15
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Abstract
Campylobacter jejuni is a major cause of food-borne gastroenteritis worldwide. While mortality is low, morbidity imparted by post-infectious sequelae such as Guillain-Barré syndrome, Reiter syndrome/reactive arthritis and irritable bowel syndrome is significant. In addition, the economic cost is high due to lost productivity. Food animals, particularly poultry, are the main reservoirs of C. jejuni. The over-use of antibiotics in the human population and in animal husbandry has led to an increase in antibiotic-resistant infections, particularly with fluoroquinolones. This is problematic because C. jejuni gastroenteritis is clinically indistinguishable from that caused by other bacterial pathogens, and such illnesses are usually treated empirically with fluoroquinolones. Since C. jejuni is naturally transformable, acquisition of additional genes imparting antibiotic resistance is likely. Therefore, an understanding of the antibiotic resistance mechanisms in C. jejuni is needed to provide proper therapy both to the veterinary and human populations.
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Affiliation(s)
- Nicole M Iovine
- University of Florida and the Malcom Randall VA Medical Center, Gainesville, FL, USA.
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16
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Cody AJ, Maiden MJC, Dingle KE. Genetic diversity and stability of the porA allele as a genetic marker in human Campylobacter infection. MICROBIOLOGY-SGM 2009; 155:4145-4154. [PMID: 19744989 PMCID: PMC2885669 DOI: 10.1099/mic.0.031047-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The major outer-membrane protein (MOMP) of Campylobacter jejuni and Campylobacter coli, encoded by the porA gene, is extremely genetically diverse. Conformational MOMP epitopes are important in host immunity, and variation in surface-exposed regions probably occurs as a result of positive immune selection during infection. porA diversity has been exploited in genotyping studies using highly discriminatory nucleotide sequences to identify potentially epidemiologically linked cases of human campylobacteriosis. To understand the overall nature and extent of porA diversity and stability in C. jejuni and C. coli we investigated sequences in isolates (n=584) obtained from a defined human population (approx. 600 000) over a defined time period (1 year). A total of 196 distinct porA variants were identified. Regions encoding putative extracellular loops were the most variable in both nucleotide sequence and length. Phylogenetic analysis identified three porA allele clusters that originated in (i) predominantly C. jejuni and a few C. coli, (ii) solely C. jejuni or (iii) predominantly C. coli and a few C. jejuni. The stability of porA within an individual human host was investigated using isolates cultured longitudinally from 64 sporadic cases, 27 of which had prolonged infection lasting between 5 and 98 days (the remainder having illness of normal duration, 0–4 days), and 20 cases from family outbreaks. Evidence of mutation was detected in two patients with prolonged illness. Despite demonstrable positive immune selection in these two unusual cases, the persistence of numerous variants within the population indicated that the porA allele is a valuable tool for use in extended typing schemes.
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Affiliation(s)
- A J Cody
- The Tinbergen Building, Department of Zoology, University of Oxford, South Parks Road, OX1 3PS, UK
| | - M J C Maiden
- The Tinbergen Building, Department of Zoology, University of Oxford, South Parks Road, OX1 3PS, UK
| | - K E Dingle
- National Institute for Health Research, Oxford Biomedical Research Centre Programme, John Radcliffe Hospital, Oxford OX3 9DU, UK.,Nuffield Department of Clinical Laboratory Sciences, Oxford University, John Radcliffe Hospital, Oxford OX3 9DU, UK
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17
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Abstract
Drug efflux pumps play a key role in drug resistance and also serve other functions in bacteria. There has been a growing list of multidrug and drug-specific efflux pumps characterized from bacteria of human, animal, plant and environmental origins. These pumps are mostly encoded on the chromosome, although they can also be plasmid-encoded. A previous article in this journal provided a comprehensive review regarding efflux-mediated drug resistance in bacteria. In the past 5 years, significant progress has been achieved in further understanding of drug resistance-related efflux transporters and this review focuses on the latest studies in this field since 2003. This has been demonstrated in multiple aspects that include but are not limited to: further molecular and biochemical characterization of the known drug efflux pumps and identification of novel drug efflux pumps; structural elucidation of the transport mechanisms of drug transporters; regulatory mechanisms of drug efflux pumps; determining the role of the drug efflux pumps in other functions such as stress responses, virulence and cell communication; and development of efflux pump inhibitors. Overall, the multifaceted implications of drug efflux transporters warrant novel strategies to combat multidrug resistance in bacteria.
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Affiliation(s)
- Xian-Zhi Li
- Human Safety Division, Veterinary Drugs Directorate, Health Products and Food Branch, Health Canada, Ottawa, Ontario K1A OK9, Canada
| | - Hiroshi Nikaido
- Department of Molecular and Cell Biology, University of California, Berkeley, California 94720-3202, USA
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19
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Clark CG, Beeston A, Bryden L, Wang G, Barton C, Cuff W, Gilmour MW, Ng LK. Phylogenetic relationships of Campylobacter jejuni based on porA sequences. Can J Microbiol 2007; 53:27-38. [PMID: 17496947 DOI: 10.1139/w06-099] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Campylobacter porins are the dominant major outer membrane protein (MOMP) of these bacteria. They are composed of hypervariable, surface-exposed, peptide loops and membrane-embedded, conserved peptide regions. Porins are functionally important and may also be useful for molecular subtyping methods but have not yet been well characterized. We therefore sequenced the porA gene from 39 Campylobacter isolates, including multilocus sequence type (MLST) reference strains, isolates from patients with the Guillain-Barré syndrome, other clinical isolates, and serotyping reference strains. These were compared with additional sequences available from GenBank. Three distinct porA lineages were observed after phylogenetic analysis. Both Campylobacter coli and Campylobacter jejuni were found with group 3 porA sequences, and this was the only group showing any evidence of recombination among porA genes. There was no recombination between porA genes from C. jejuni groups 1 and 2, suggesting there may be functional constraints on changes at this locus. Most of the amino acid differences among the three groups were present in surface-exposed loops, and dissimilar substitutions were found when groups 1 and 2 MOMP were compared. Different MOMP sequence groups may have different biological or antigenic properties, which in turn may be associated with survival in different environments, host adaptation, or virulence.
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Affiliation(s)
- Clifford G Clark
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB.
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20
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Abstract
Campylobacter, Helicobacter and Wolinella are genera of the order Campylobacterales, belonging to the class Epsilonproteobacteria. Their habitats are various niches in the gastrointestinal tract of higher animals, where they may come into contact with bile. Microorganisms in these environments require mechanisms of resistance to the surface-active amphipathic molecules with potent antimicrobial activities present in bile. This review summarizes current knowledge on the molecular responses to bile by Campylobacterales and other bacterial species that inhabit the intestinal tract and belong to the phyla Proteobacteria, Bacteriodetes, Firmicutes and Actinobacteria. To date, 125 specific genes have been implicated in bile responses, of which 10 are found in Campylobacterales. Genome database searches, analyses of protein sequence and domain similarities, and gene ontology data integration were performed to compare the responses to bile of these bacteria. The results showed that 33 proteins of bacteria belonging to the four phyla had similarities equal to or greater than 50-46% proteins of Campylobacterales. Domain architecture analyses revealed that 151 Campylobacterales proteins had similar domain composition and organization to 60 proteins known to participate in the tolerance to bile in other bacteria. The proteins CmeB, CmeF and CbrR of Campylobacter jejuni involved in bile tolerance were homologous to 42 proteins identified in the Proteobacteria, Bacteriodetes and Firmicutes. On the other hand, the proteins CiaB, CmeA, CmeC, CmeD, CmeE and FlaAsigma(28) also involved in the response to bile of C. jejuni, did not have homologues in other bacteria. Among the bacteria inhabiting the gastrointestinal tract, the Campylobacterales seem to have evolved some mechanisms of bile resistance similar to those of other bacteria, as well as other mechanisms that appear to be characteristic of this order.
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Affiliation(s)
- Arinze S Okoli
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, Australia
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21
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Huang S, Luangtongkum T, Morishita TY, Zhang Q. Molecular typing of Campylobacter strains using the cmp gene encoding the major outer membrane protein. Foodborne Pathog Dis 2005; 2:12-23. [PMID: 15992295 DOI: 10.1089/fpd.2005.2.12] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Thermophilic Campylobacter, particularly Campylobacter jejuni, is one of the major foodborne human pathogens of animal origin. Reliable and sensitive typing tools are required for understanding the epidemiology and ecology of this zoonotic bacteria agent. Currently, several molecular typing methods are available for differentiating Campylobacter strains, but each of them has limitations. Our previous study revealed that considerable sequence polymorphism exists in the cmp gene encoding the major outer membrane protein of Campylobacter and suggested that sequence variation of cmp may be utilized for discrimination of Campylobacter strains. In this study, we evaluated the feasibility of the cmp-based typing tool, using pulsed-field gel electrophoresis (PFGE) as the "gold" standard for comparison. The cmp alleles were sequenced from multiple Campylobacter strains, grouped, and compared with the PFGE profiles of these strains using Bionumerics. Results showed that 43 cmp sequence types and 43 PFGE types existed among the 60 Campylobacter isolates. Typeability of these strains is 100% using either the cmp-based method or PFGE. The discrimination indices are 0.973 for the cmp-based method and 0.969 for PFGE, respectively. The cmp sequence types are 77.6% congruent with the PFGE types. These results indicate that the cmp-based typing is a simple, yet highly discriminatory approach for molecular differentiation of C. jejuni strains.
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Affiliation(s)
- Shouxiong Huang
- Food Animal Health Research Program, Ohio Agriculture Research and Development Center, The Ohio State University, Wooster, Ohio, USA
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22
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Payot S, Cloeckaert A, Chaslus-Dancla E. Selection and characterization of fluoroquinolone-resistant mutants of Campylobacter jejuni using enrofloxacin. Microb Drug Resist 2003; 8:335-43. [PMID: 12523631 DOI: 10.1089/10766290260469606] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Significant levels of fluoroquinolone resistance were obtained in Campylobacterjejuni isolates after an unique step of selection using enrofloxacin. An Asp90-to-Asn and a Thr86-to-Ile change in the gyrase subunit GyrA were found associated with a low (MIC < or = 8 /microg/ml) or a high (MIC > or = 16 microg/ml) level of resistance to ciprofloxacin, respectively. An association of both mutations conferred a higher level of resistance (MIC > or = 128 microg/ml). Further steps of selection increased the MICs of fluoroquinolones but did not result in a multiple antibiotic resistance phenotype. The Thr86-to-Ile change was found to confer different levels of resistance, pointing out other mechanisms of resistance. However, sequencing revealed no mutation in gyrB, and several attempts did not enable any amplification of the parC gene coding for topoisomerase IV, suggesting an absence of this secondary target in C. jejuni. In addition, no difference in the major outer membrane protein expression was found among the isolates. Furthermore, the use of the recently identified efflux pump inhibitor Phe-Arg-beta-naphthylamide did not result in a significant decrease of fluoroquinolone MICs or change in the frequency of isolation of enrofloxacin-resistant mutants, and thus appears ineffective against fluoroquinolone-resistant C. jejuni isolates. Results obtained during ciprofloxacin accumulation studies confirmed that efflux probably plays a minor role in fluoroquinolone resistance of C. jejuni.
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Affiliation(s)
- Sophie Payot
- UR86 de Pathologie Aviaire et Parasitologie, Institut National de la Recherche Agronomique, 37380 Nouzilly, France.
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23
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Dedieu L, Pagès JM, Bolla JM. Environmental regulation of Campylobacter jejuni major outer membrane protein porin expression in Escherichia coli monitored by using green fluorescent protein. Appl Environ Microbiol 2002; 68:4209-15. [PMID: 12200267 PMCID: PMC124132 DOI: 10.1128/aem.68.9.4209-4215.2002] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Porins allow exchanges between bacteria and their environment. In the gram-negative food-borne pathogen Campylobacter jejuni two porins, major outer membrane protein (MOMP) and Omp50, have been identified. MOMP is synthesized at a very high level under laboratory culture conditions, suggesting that its promoter functions very efficiently under these conditions. In Campylobacter samples, we observed that MOMP porin expression increased at a high temperature (42 degrees C) or a high pH (pH 8.5) compared to expression at a low temperature (31 degrees C) or an acidic pH (pH 5.5). To study the regulation of MOMP expression at the transcriptional level, we constructed an momp-gfp fusion in which gfp expression was put under the control of the momp promoter. Interestingly, we observed the same pattern of regulation in Escherichia coli, as monitored by green fluorescent protein production, that was found in CAMPYLOBACTER: The ranges of pH and temperature tested are physiologically relevant, because they can be found in the digestive tracts of both birds and humans, which are both colonized by CAMPYLOBACTER: Our results suggest that a component of the regulatory mechanism is conserved in C. jejuni and E. coli. However, medium osmolarity and sodium salicylate did not have a significant effect on C. jejuni momp promoter activity in E. coli, suggesting that major regulatory elements of E. coli porin expression do not participate in MOMP regulation. In contrast, mechanisms involving DNA supercoiling may be involved, as shown by DNA gyrase inhibition assays. These findings are a step towards determining the role of outer membrane proteins in the adaptation of C. jejuni to its environment.
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Affiliation(s)
- Luc Dedieu
- CJF 96-06 INSERM, EA 2197 and IFR 48, Faculté de Médecine, Université de la Méditerranée, 13385 Marseille Cedex 5, France
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24
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Identification of an OmpA Protein from Bacteroides fragilis: omp A Gene Sequence, OmpA Amino Acid Sequence and Predictions of Protein Structure. Anaerobe 2002. [DOI: 10.1006/anae.2002.0427] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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25
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Labesse G, Garnotel E, Bonnel S, Dumas C, Pages JM, Bolla JM. MOMP, a divergent porin from Campylobacter: cloning and primary structural characterization. Biochem Biophys Res Commun 2001; 280:380-7. [PMID: 11162527 DOI: 10.1006/bbrc.2000.4129] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We report a structural analysis at the molecular level of MOMP from Campylobacter, a gram-negative bacteria responsible for diarrhea. The corresponding gene was cloned and sequenced. Sequence comparison of seven MOMP sequences (three extracted from protein databases and four determined in this study) from distinct strains indicated alternation of preserved and divergent regions. No other significant sequence similarities could be detected. Comparison of MOMP with the crystal structures of other porins strongly suggested that it might adopt a similar fold and revealed the conservation of the monomer-monomer interface. The conservation clustered in the regions comprising or interacting with the loop L2. On the contrary, strands not involved in the interface are more divergent. Proteolysis assays and biochemical treatment supported the proposed model. Our study suggested that MOMP belong to the maltoporin super-family sharing common structural motifs. In view of this model we discuss its specificity and its global stability.
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Affiliation(s)
- G Labesse
- INSERM-CJF, 9606 Faculté de Médecine, 27 boulevard Jean Moulin, 13385 Marseille cedex 5, France
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26
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Bolla JM, Dé E, Dorez A, Pagès JM. Purification, characterization and sequence analysis of Omp50,a new porin isolated from Campylobacter jejuni. Biochem J 2000; 352 Pt 3:637-43. [PMID: 11104668 PMCID: PMC1221499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
A novel pore-forming protein identified in Campylobacter was purified by ion-exchange chromatography and named Omp50 according to both its molecular mass and its outer membrane localization. We observed a pore-forming ability of Omp50 after re-incorporation into artificial membranes. The protein induced cation-selective channels with major conductance values of 50-60 pS in 1 M NaCl. N-terminal sequencing allowed us to identify the predicted coding sequence Cj1170c from the Campylobacter jejuni genome database as the corresponding gene in the NCTC 11168 genome sequence. The gene, designated omp50, consists of a 1425 bp open reading frame encoding a deduced 453-amino acid protein with a calculated pI of 5.81 and a molecular mass of 51169.2 Da. The protein possessed a 20-amino acid leader sequence. No significant similarity was found between Omp50 and porin protein sequences already determined. Moreover, the protein showed only weak sequence identity with the major outer-membrane protein (MOMP) of Campylobacter, correlating with the absence of antigenic cross-reactivity between these two proteins. Omp50 is expressed in C. jejuni and Campylobacter lari but not in Campylobacter coli. The gene, however, was detected in all three species by PCR. According to its conformation and functional properties, the protein would belong to the family of outer-membrane monomeric porins.
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Affiliation(s)
- J M Bolla
- CJF 96-06 INSERM, Faculté de Médecine la Timone, Université de la Méditerranée, 27 Bd Jean Moulin, 13385 Marseille Cedex 05, France.
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27
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Zhang Q, Meitzler JC, Huang S, Morishita T. Sequence polymorphism, predicted secondary structures, and surface-exposed conformational epitopes of Campylobacter major outer membrane protein. Infect Immun 2000; 68:5679-89. [PMID: 10992471 PMCID: PMC101523 DOI: 10.1128/iai.68.10.5679-5689.2000] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The major outer membrane protein (MOMP), a putative porin and a multifunction surface protein of Campylobacter jejuni, may play an important role in the adaptation of the organism to various host environments. To begin to dissect the biological functions and antigenic features of this protein, the gene (designated cmp) encoding MOMP was identified and characterized from 22 strains of C. jejuni and one strain of C. coli. It was shown that the single-copy cmp locus encoded a protein with characteristics of bacterial outer membrane proteins. Prediction from deduced amino acid sequences suggested that each MOMP subunit consisted of 18 beta-strands connected by short periplasmic turns and long irregular external loops. Alignment of the amino acid sequences of MOMP from different strains indicated that there were seven localized variable regions dispersed among highly conserved sequences. The variable regions were located in the putative external loop structures, while the predicted beta-strands were formed by conserved sequences. The sequence homology of cmp appeared to reflect the phylogenetic proximity of C. jejuni strains, since strains with identical cmp sequences had indistinguishable or closely related macrorestriction fragment patterns. Using recombinant MOMP and antibodies recognizing linear or conformational epitopes of the protein, it was demonstrated that the surface-exposed epitopes of MOMP were predominantly conformational in nature. These findings are instrumental in the design of MOMP-based diagnostic tools and vaccines.
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Affiliation(s)
- Q Zhang
- Food Animal Health Research Program, The Ohio State University, Wooster, Ohio 44691, USA.
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28
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Dé E, Jullien M, Labesse G, Pagès JM, Molle G, Bolla JM. MOMP (major outer membrane protein) of Campylobacter jejuni; a versatile pore-forming protein. FEBS Lett 2000; 469:93-7. [PMID: 10708763 DOI: 10.1016/s0014-5793(00)01244-8] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
The great majority of trimeric porins of Gram-negative bacteria cannot be dissociated into monomers without disrupting their folded conformation. The porin of Campylobacter jejuni, however, displays two folded structures, a classical oligomer and a monomer resistant to detergent denaturation. We probed the transition of trimer to monomer using light scattering experiments and examined the secondary structures of these two molecular states by infra-red spectroscopy. The channel-forming properties of both trimer and monomer were studied after incorporation into artificial lipid bilayers. In these conditions, the trimer induced ion channels with a conductance value of 1200 pS in 1 M NaCl. The pores showed marked cationic selectivity and sensitivity to low voltage. Analysis of the isolated monomer showed nearly the same single-channel conductance and the same selectivity and sensitivity to voltage. These results indicate that the folded monomer form of C. jejuni MOMP displays essentially the same pore-forming properties as the native trimer.
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Affiliation(s)
- E Dé
- UMR 6522, CNRS, IFRMP 23, Faculté des Sciences, 76821, Mont-Saint-Aignan, France
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29
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Shannon JL, Fernandez RC. The C-terminal domain of the Bordetella pertussis autotransporter BrkA forms a pore in lipid bilayer membranes. J Bacteriol 1999; 181:5838-42. [PMID: 10482528 PMCID: PMC94107 DOI: 10.1128/jb.181.18.5838-5842.1999] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
BrkA is a 103-kDa outer membrane protein of Bordetella pertussis that mediates resistance to antibody-dependent killing by complement. It is proteolytically processed into a 73-kDa N-terminal domain and a 30-kDa C-terminal domain as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. BrkA is also a member of the autotransporter family of proteins. Translocation of the N-terminal domain of the protein across the outer membrane is hypothesized to occur through a pore formed by the C-terminal domain. To test this hypothesis, we performed black lipid bilayer experiments with purified recombinant protein. The BrkA C-terminal protein showed an average single-channel conductance of 3.0 nS in 1 M KCl. This result strongly suggests that the C-terminal autotransporter domain of BrkA is indeed capable of forming a pore.
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Affiliation(s)
- J L Shannon
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
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30
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Odou MF, Singer E, Romond MB, Dubreuil L. Isolation and characterization of a porin-like protein of 45 kilodaltons from Bacteroides fragilis. FEMS Microbiol Lett 1998; 166:347-54. [PMID: 9770292 DOI: 10.1111/j.1574-6968.1998.tb13911.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Resistance to the combination of amoxicillin and clavulanic acid in some Bacteroides fragilis strains may be associated with a lack of porin proteins. Comparison of outer membrane protein profiles from one resistant strain (B. fragilis CFPL 358) and two susceptible strains of B. fragilis (ATCC 25285 and CFPL 92125) showed that a few proteins were missing in the resistant strain, especially a 45-kDa protein. To determine whether this protein was a porin-like protein, we attempted to isolate it from the two susceptible strains by using gel filtration (Sephacryl S-200, Superose 6) and ion exchange chromatographies (DEAE Trisacryl, DEAE Sepharose Fast Flow). Elution from DEAE resins was poor compared to the 60-67-kDa region, which suggested that the 45-kDa protein exhibited stronger cationic forms. The use of sodium dodecyl sulfate during elution improved the recovery of the 45-kDa protein, showing that detergent modified its conformation and its ionic bounds with the chromatographic matrices but it was not sufficient for good purification. Superose 6 gel filtration also failed to separate this protein from the 60-67-kDa region. The only method resulting in the positive recovery of a purified 45-kDa band from both susceptible B. fragilis strains was electroelution from SDS-PAGE. The swelling assay showed that the 45-kDa protein was a porin-like protein. From this study, we concluded that the 45-kDa protein from B. fragilis was a porin-like protein which might be involved in the antibiotic resistance of a strain in which this protein was missing.
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Affiliation(s)
- M F Odou
- Laboratoire de Bactériologie, Faculté des Sciences Pharmaceutiques et Biologiques, Lille, France
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31
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Amako K, Wai SN, Umeda A, Shigematsu M, Takade A. Electron microscopy of the major outer membrane protein of Campylobacter jejuni. Microbiol Immunol 1996; 40:749-54. [PMID: 8981348 DOI: 10.1111/j.1348-0421.1996.tb01136.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The surfaces of the disrupted-cell surfaces of the Campylobacter jejuni strains FUM158432 and M1 were examined using the negative-staining technique and electron microscopy. The surfaces of the whole cells and the outer membranes were covered with small dark dots which, in some areas, were arranged in hexagonal patterns. The hexagonal arrangement was more clearly seen in extracted outer membrane. The size of each structure was measured based on a center-to-center distance with the adjacent structure, and was determined to be 9.9 +/- 0.9 nm. A profile of the proteins in the outer membrane by SDS-PAGE, performed in 0.1% SDS and at 100 C, showed 42 kDa proteins to comprise the major outer membrane protein of this bacterium. Digestion of the outer membrane materials with proteinase reduced this protein band in the SDS-PAGE, and the amount of dark dots on the electron micrograph indicated the structure to be the major outer membrane protein (porin) of this bacterium. The power spectrogram of a computer-assisted Fourier transformation of the hexagonally arranged porin proteins suggests that the porin has a trimeric structure rather than a monomeric one.
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Affiliation(s)
- K Amako
- Department of Bacteriology, Faculty of Medicine, Kyushu University, Fukuoka, Japan
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32
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Tajada P, Gomez-Graces JL, Alós JI, Balas D, Cogollos R. Antimicrobial susceptibilities of Campylobacter jejuni and Campylobacter coli to 12 beta-lactam agents and combinations with beta-lactamase inhibitors. Antimicrob Agents Chemother 1996; 40:1924-5. [PMID: 8843305 PMCID: PMC163441 DOI: 10.1128/aac.40.8.1924] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The in vitro activities of 12 beta-lactam agents against 100 thermophilic Campylobacter strains were tested. Beta-Lactamase production was detected in 88% of all strains tested. Clavulanic acid was the best inhibitor by susceptibility testing. The beta-lactams which displayed high levels of in vitro activity against Campylobacter isolates were imipenem, amoxicillin-clavulanic acid, and cefepime and, to a lesser degree, amoxicillin, ampicillin, and cefotaxime.
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Affiliation(s)
- P Tajada
- Servicio de Microbiología, Hospital de Móstoles, Móstoles, Madrid, Spain
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33
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Burnens AP, Heitz M, Brodard I, Nicolet J. Sequential development of resistance to fluoroquinolones and erythromycin in an isolate of Campylobacter jejuni. ZENTRALBLATT FUR BAKTERIOLOGIE : INTERNATIONAL JOURNAL OF MEDICAL MICROBIOLOGY 1996; 283:314-21. [PMID: 8861869 DOI: 10.1016/s0934-8840(96)80065-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A severe episode of Campylobacter jejuni gastroenteritis in a patient with HIV infection was treated with ciprofloxacin and, because of therapeutic failure, subsequently with roxithromycin. After treatment, C. jejuni was again isolated from feces and shown to be resistant to both drugs. We present molecular evidence of the sequential development of both types of resistance in the patient isolate. To our knowledge, this is the first case with documented evidence showing sequential emergence of resistance to fluoroquinolones and erythromycin in a strain of C. jejuni during treatment.
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Affiliation(s)
- A P Burnens
- National Reference Laboratory for Foodborne Diseases, University of Berne, Berne, Switzerland
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34
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Doig P, Exner MM, Hancock RE, Trust TJ. Isolation and characterization of a conserved porin protein from Helicobacter pylori. J Bacteriol 1995; 177:5447-52. [PMID: 7559328 PMCID: PMC177350 DOI: 10.1128/jb.177.19.5447-5452.1995] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Helicobacter pylori is a causative agent of gastritis in humans and is correlated with gastric ulcer formation. Infections with this bacterium have proven difficult to treat with antimicrobial agents. To better understand how this bacterium transports compounds such as antimicrobial agents across its outer membrane, identification of porin proteins is important. We have recently identified a family of H. pylori porins (HopA to HopD) (M. M. Exner, P. Doig, T. J. Trust, and R. E. W. Hancock, Infect. Immun. 63:1567-1572, 1995). Here, we report on an unrelated porin species (HopE) from this bacterium. This protein had a apparent molecular mass of 31 kDa and was seen to form 50- and 90-kDa aggregates that were designated putative dimeric and trimeric forms, respectively. The protein was purified to homogeneity and, with a model planar lipid membrane system, was shown to act as a nonselective pore with a single channel conductance in 1.0 M KCl of 1.5 nS, similarly to other bacterial nonspecific porins. An internal peptide sequence of HopE shared homology with the P2 porin of Haemophilus influenzae. HopE was also shown to be antigenic in vivo as assessed by sera taken from H. pylori-infected individuals and was immunologically conserved with both patient sera and specific monoclonal antibodies. From these data, it appears that HopE is a major nonselective porin of H. pylori. The implications of these findings are discussed.
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Affiliation(s)
- P Doig
- Canadian Bacterial Diseases Network, University of Victoria, British Columbia, Canada
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35
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Charvalos E, Tselentis Y, Hamzehpour MM, Köhler T, Pechere JC. Evidence for an efflux pump in multidrug-resistant Campylobacter jejuni. Antimicrob Agents Chemother 1995; 39:2019-22. [PMID: 8540709 PMCID: PMC162874 DOI: 10.1128/aac.39.9.2019] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Mechanisms of drug resistance in Campylobacter jejuni were investigated. Mutant strains 34PEFr, which was resistant to pefloxacin (128-fold increase in the MIC), and 34CTXr, which was resistant to cefotaxime (32-fold increase in the MIC) and which was derived from the susceptible parent 34s, were obtained by serial passages on pefloxacin and cefotaxime gradient plates, respectively. Both mutants showed cross-resistance to erythromycin, chloramphenicol, tetracycline, beta-lactams, and quinolones. While the quinolone resistance of strain PEFr could be explained by a mutation at codon 86 of the gyrA gene, the multidrug resistance phenotype of both strains was further investigated. Accumulation of pefloxacin, ciprofloxacin, and minocycline was measured by fluorometry and was found to be lower in the mutant strains than in the parent strain. Preincubation of the cells with carbonyl cyanide m-chlorophenylhydrazone, however, completely abolished this difference. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of outer membrane preparations from both mutant strains showed overexpression of two proteins of 55 and 39 kDa which were absent from the outer membranes of the wild-type strain. These results indicate that in C. jejuni 34PEFr and 34CTXr, multidrug resistance is associated with an efflux system with a broad specificity.
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Affiliation(s)
- E Charvalos
- Department of Bacteriology, Parasitology, Zoonoses and Geographical Medicine, School of Health Sciences, University of Crete, Herakleion, Greece
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36
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Shang ES, Exner MM, Summers TA, Martinich C, Champion CI, Hancock RE, Haake DA. The rare outer membrane protein, OmpL1, of pathogenic Leptospira species is a heat-modifiable porin. Infect Immun 1995; 63:3174-81. [PMID: 7622245 PMCID: PMC173433 DOI: 10.1128/iai.63.8.3174-3181.1995] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The outer membranes of invasive spirochetes contain unusually small amounts of transmembrane proteins. Pathogenic Leptospira species produce a rare 31-kDa surface protein, OmpL1, which has a deduced amino acid sequence predictive of multiple transmembrane beta-strands. Studies were conducted to characterize the structure and function of this protein. Alkali, high-salt, and urea fractionation of leptospiral membranes demonstrated that OmpL1 is an integral membrane protein. The electrophoretic mobility of monomeric OmpL1 was modifiable by heat and reduction; complete denaturation of OmpL1 required prolonged boiling in sodium dodecyl sulfate (SDS), 8 M urea, and 2-mercaptoethanol. When solubilized in SDS at low temperature, a small proportion of OmpL1 exhibited an apparent molecular mass of approximately 90 kDa, indicating the existence of an SDS-unstable oligomer. OmpL1 dimers and trimers were demonstrated by nearest neighbor chemical cross-linking. In order to generate purified protein for functional studies, the ompL1 gene was ligated into the pMMB66 expression plasmid under control of the tac promoter. Although expression in Escherichia coli was toxic, most of the OmpL1 produced was found in the outer membrane, as determined by subcellular fractionation. Purified recombinant OmpL1 was reconstituted into planar lipid bilayers, demonstrating an average single channel conductance of 1.1 nS, similar to the major porin activity of native leptospiral membranes. These findings indicate that OmpL1 spans the leptospiral outer membrane and functions as a porin.
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Affiliation(s)
- E S Shang
- Department of Microbiology & Immunology, UCLA School of Medicine 90024, USA
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37
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Gomez-Garces JL, Cogollos R, Alos JL. Susceptibilities of fluoroquinolone-resistant strains of Campylobacter jejuni to 11 oral antimicrobial agents. Antimicrob Agents Chemother 1995; 39:542-44. [PMID: 7726529 PMCID: PMC162576 DOI: 10.1128/aac.39.2.542] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The resistance of Campylobacter jejuni strains to the fluoroquinolones is increasingly frequent, and in our area it reaches nearly 50%. We studied the susceptibilities of 60 of these strains to 11 oral antibiotics. All strains except one were susceptible to the macrolides tested, with azithromycin being the most active agent tested. Of the rest of the antibiotics studied, amoxicillin-clavulanic acid, clindamycin, and fosfomycin displayed good in vitro activities. Knowledge of the susceptibilities of these microorganisms to a varied group of oral agents is necessary in view of the appearance of multiresistant strains, such as those included in our series.
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38
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Abstract
Despite the potential significance of surface-localized antigens in the colonization by and disease processes of Helicobacter pylori, few such components have been unequivocally identified and/or characterized. To further investigate the surface of this bacterium, monoclonal antibodies (MAbs) to a sarcosine-insoluble outer membrane fraction prepared from H. pylori NCTC 11637 were raised. MAbs were selected on the basis of their surface reactivity to whole cells by enzyme-linked immunosorbent assay, immunofluorescence, and immunoelectron microscopy. By use of this selection protocol, 14 surface-reactive MAbs were chosen. These MAbs were used to identify six protein antigens (molecular masses, 80, 60, 51, 50, 48, and 31 kDa), all of which were localized within or associated with the outer membrane. Two of the MAbs recognized the core region of lipopolysaccharide (LPS). Only these two anti-LPS MAbs also recognized the flagellar sheath, indicating a structural difference between the sheath and outer membrane. Three of the protein antigens (80, 60, and 51 kDa) were strain specific, while the other three antigens were present in other strains of H. pylori. Both the 51- and 48-kDa antigens were heat modifiable and likely are porins. A conserved 31-kDa protein may represent another species of porin. A method involving sucrose density ultracentrifugation and Triton extraction that allows the preparation of H. pylori outer membranes with minimal inner membrane contamination is described. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed that the protein content of the H. pylori outer membrane is similar structurally to those of other species of Helicobacter but markedly different from those of taxonomically related Campylobacter spp. and Escherichia coli. H. pylori also appeared to lack peptidoglycan-associated proteins.
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Affiliation(s)
- P Doig
- Department of Biochemistry and Microbiology, University of Victoria, British Columbia, Canada
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39
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40
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Gootz TD, Martin BA. Characterization of high-level quinolone resistance in Campylobacter jejuni. Antimicrob Agents Chemother 1991; 35:840-5. [PMID: 1649570 PMCID: PMC245117 DOI: 10.1128/aac.35.5.840] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
High-level resistance to quinolones has previously been shown to occur in Campylobacter spp. both in vitro and in patients treated with quinolones. We have selected isolates that are resistant to quinolones by plating cells from a susceptible C. jejuni strain, UA535, on medium containing nalidixic acid at 32 micrograms/ml. Fluctuation analysis indicated that resistance occurred by mutation at a frequency of 5 x 10(-8) per cell plated. Unlike what is observed with other gram-negative organisms, the nalidixic acid-resistant mutants demonstrated high-level cross-resistance (MIC, greater than or equal to 4 micrograms/ml) to newer quinolones, including ciprofloxacin, norfloxacin, and temafloxacin, yet remained susceptible to coumermycin A1 and several other unrelated antibiotics. Mutants with an identical resistance phenotype could also be selected from UA535 with ciprofloxacin and norfloxacin at a similar frequency. To study the mechanism of quinolone resistance, DNA gyrases were purified from C. jejuni UA535 and two resistant mutants by heparin-agarose and novobiocin-Sepharose chromatography. After the respective enzyme concentrations were adjusted to equivalent units of activity in the DNA supercoiling reaction, the DNA gyrases from the resistant mutants were found to be 100-fold less susceptible than the wild-type enzyme to inhibition by quinolones. Subunit switching experiments with purified A and B subunits from the wild type and one of the quinolone-resistant mutants indicated that an alteration in the A subunit was responsible for resistance. These results show that a single-step mutation can occur in vitro in the gene encoding DNA gyrase in C. jejuni, producing clinically relevant levels of resistance to the newer quinolones.
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Affiliation(s)
- T D Gootz
- Central Research Division, Pfizer Inc., Groton, Connecticut 06340
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41
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Lachance N, Gaudreau C, Lamothe F, Larivière LA. Role of the beta-lactamase of Campylobacter jejuni in resistance to beta-lactam agents. Antimicrob Agents Chemother 1991; 35:813-8. [PMID: 1854162 PMCID: PMC245112 DOI: 10.1128/aac.35.5.813] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
We studied the role of the beta-lactamase of Campylobacter jejuni in resistance to beta-lactam agents. beta-Lactamase-positive strains were more resistant than beta-lactamase-negative strains to amoxicillin, ampicillin, and ticarcillin (P less than 0.05). With penicillin G, piperacillin, imipenem, and six cephalosporins, the susceptibility levels were similar for both beta-lactamase-positive and -negative strains. By using spectrophotometric and microbiological assays, the beta-lactamase from three strains hydrolyzed ampicillin, amoxicillin, penicillin G, cloxacillin, and, partially, cephalothin. Ticarcillin and piperacillin were partially hydrolyzed in the microbiological assay. There was no activity against five other cephalosporins or imipenem. Isoelectric focusing of the enzyme showed a pI of 8.8. Tazobactam was the best inhibitor of the enzyme, followed by clavulanic acid, sulbactam, and cefoxitin, while EDTA and p-chloromercuribenzoate had no activity. All beta-lactamase-positive strains became susceptible to amoxicillin and ampicillin with 1 micrograms of clavulanic acid per ml. With the same inhibitor, there was a reduced but significant effect for ticarcillin but no effect for penicillin G or piperacillin. Sulbactam had no effect and tazobactam was effective only at 2 micrograms/ml on amoxicillin and ampicillin. The beta-lactamase of C. jejuni seems to be a penicillinase with a role in resistance for only amoxicillin, ampicillin, and ticarcillin.
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Affiliation(s)
- N Lachance
- Service de Microbiologie Médicale et Maladies Infectieuses, Hôpital Saint-Luc, Montréal, Québec, Canada
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42
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