1
|
Kumari K, Aggarwal Y, Singh RP. Molecular characterization and in-depth genomic analysis to unravel the pathogenic features of an environmental isolate Enterobacter sp. S-33. Int Microbiol 2024; 27:1095-1110. [PMID: 38044418 DOI: 10.1007/s10123-023-00461-y] [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: 08/17/2023] [Revised: 11/21/2023] [Accepted: 11/24/2023] [Indexed: 12/05/2023]
Abstract
Enterobacter species represent widely distributed opportunistic pathogens, commonly associated with plants and humans. In the present study, we performed a detailed molecular characterization as well as genomic study of a type VI secretion system (T6SS) bacterium belonging to member of the family Enterobacteriaceae and named Enterobacter sp. S-33. The comparative sequence analysis of the 16S rRNA gene showed that the strain was closely related to other Enterobacter species. The complete genome of the strain with a genome size of 4.6 Mbp and GC-content of 55.63% was obtained through high-quality sequencing. The genomic analysis with online tools unravelled the various genes belonging to the bacterial secretion system, antibiotic resistance, virulence, efflux pumps, etc. The isolate showed the motility behavior that contributes to Enterobacter persistence in a stressed environment and further supports infections. PCR amplification and further sequencing confirmed the presence of drug-efflux genes acrA, acrB, and outer membrane genes, viz. OmpA, OmpC, and OmpF. The cell surface hydrophobicity and co-aggregation assay against different bacterial strains illustrated its putative pathogenic nature. Genome mining identified various biosynthetic gene clusters (BGCs) corresponding to non-ribosomal proteins (NRPS), siderophore, and arylpolyene production. Briefly, genome sequencing and detailed characterization of environmental Enterobacter isolate will assist in understanding the epidemiology of Enterobacter species, and the further prevention and treatment of infectious diseases caused by these broad-host range species.
Collapse
Affiliation(s)
- Kiran Kumari
- Department of Bioengineering and Biotechnology, Birla Institute of Technology, Mesra, Ranchi, Jharkhand, 835215, India
| | - Yogender Aggarwal
- Department of Bioengineering and Biotechnology, Birla Institute of Technology, Mesra, Ranchi, Jharkhand, 835215, India
| | - Rajnish Prakash Singh
- Department of Biotechnology, Jaypee Institute of Information Technology, Noida, India.
| |
Collapse
|
2
|
Zhou G, Wang Q, Wang Y, Wen X, Peng H, Peng R, Shi Q, Xie X, Li L. Outer Membrane Porins Contribute to Antimicrobial Resistance in Gram-Negative Bacteria. Microorganisms 2023; 11:1690. [PMID: 37512863 PMCID: PMC10385648 DOI: 10.3390/microorganisms11071690] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Revised: 06/21/2023] [Accepted: 06/23/2023] [Indexed: 07/30/2023] Open
Abstract
Gram-negative bacteria depend on their cell membranes for survival and environmental adaptation. They contain two membranes, one of which is the outer membrane (OM), which is home to several different outer membrane proteins (Omps). One class of important Omps is porins, which mediate the inflow of nutrients and several antimicrobial drugs. The microorganism's sensitivity to antibiotics, which are predominantly targeted at internal sites, is greatly influenced by the permeability characteristics of porins. In this review, the properties and interactions of five common porins, OmpA, OmpC, OmpF, OmpW, and OmpX, in connection to porin-mediated permeability are outlined. Meanwhile, this review also highlighted the discovered regulatory characteristics and identified molecular mechanisms in antibiotic penetration through porins. Taken together, uncovering porins' functional properties will pave the way to investigate effective agents or approaches that use porins as targets to get rid of resistant gram-negative bacteria.
Collapse
Affiliation(s)
- Gang Zhou
- Key Laboratory of Agricultural Microbiomics and Precision Application (MARA), Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Key Laboratory of Agricultural Microbiome (MARA), State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Qian Wang
- Key Laboratory of Agricultural Microbiomics and Precision Application (MARA), Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Key Laboratory of Agricultural Microbiome (MARA), State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Yingsi Wang
- Key Laboratory of Agricultural Microbiomics and Precision Application (MARA), Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Key Laboratory of Agricultural Microbiome (MARA), State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Xia Wen
- Key Laboratory of Agricultural Microbiomics and Precision Application (MARA), Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Key Laboratory of Agricultural Microbiome (MARA), State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Hong Peng
- Key Laboratory of Agricultural Microbiomics and Precision Application (MARA), Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Key Laboratory of Agricultural Microbiome (MARA), State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Ruqun Peng
- Key Laboratory of Agricultural Microbiomics and Precision Application (MARA), Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Key Laboratory of Agricultural Microbiome (MARA), State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Qingshan Shi
- Key Laboratory of Agricultural Microbiomics and Precision Application (MARA), Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Key Laboratory of Agricultural Microbiome (MARA), State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Xiaobao Xie
- Key Laboratory of Agricultural Microbiomics and Precision Application (MARA), Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Key Laboratory of Agricultural Microbiome (MARA), State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Liangqiu Li
- Key Laboratory of Agricultural Microbiomics and Precision Application (MARA), Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Key Laboratory of Agricultural Microbiome (MARA), State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| |
Collapse
|
3
|
Outer membrane protein of OmpF contributes to swimming motility, biofilm formation, osmotic response as well as the transcription of maltose metabolic genes in Citrobacter werkmanii. World J Microbiol Biotechnol 2022; 39:15. [PMID: 36401137 DOI: 10.1007/s11274-022-03458-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 11/02/2022] [Indexed: 11/20/2022]
Abstract
Bacterial outer membrane proteins (Omps) are essential for environmental sensing, stress responses, and substance transport. Our previous study discovered that OmpA contributes to planktonic growth, biocide resistance, biofilm formation, and swimming motility in Citrobacter werkmanii, whereas the molecular functions of OmpF in this strain are largely unknown. Thus, in this study, the ompF gene was firstly knocked out from the genome of C. werkmanii using a homologous recombination method, and its phenotypical alternations of ∆ompF were then thoroughly characterized using biochemical and molecular approaches with the parental wild type (WT) and complementary (∆ompF-com) strains. The results demonstrated that the swimming ability of ∆ompF on semi-solid plates was reduced compared to WT due to the down-regulation of flgC, flgH, fliK, and fliF. Meanwhile, ompF deletion reduces biofilm formation on both glass and polystyrene surfaces due to decreased cell aggregation. Furthermore, ompF inactivation induced different osmotic stress (carbon sources and metal ions) responses in its biofilms when compared to WT and ∆ompF-com. Finally, a total of 6 maltose metabolic genes of lamB, malE, malK, malG, malM, and malF were all up-regulated in ∆ompF. The gene knockout and HPLC results revealed that the MalEFGK2 cluster was primarily responsible for maltose transport in C. werkmanii. Furthermore, we discovered for the first time that the upstream promoter of OmpF and its transcription can be combined with and negatively regulated by MalT. Overall, OmpF plays a role in a variety of biochemical processes and molecular functions in C. werkmanii, and it may even act as a targeted site to inhibit biofilm formation.
Collapse
|
4
|
ompX contribute to biofilm formation, osmotic response and swimming motility in Citrobacter werkmanii. Gene X 2022; 851:147019. [DOI: 10.1016/j.gene.2022.147019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 10/12/2022] [Accepted: 10/25/2022] [Indexed: 11/04/2022] Open
|
5
|
Seukep AJ, Mbuntcha HG, Kuete V, Chu Y, Fan E, Guo MQ. What Approaches to Thwart Bacterial Efflux Pumps-Mediated Resistance? Antibiotics (Basel) 2022; 11:antibiotics11101287. [PMID: 36289945 PMCID: PMC9598416 DOI: 10.3390/antibiotics11101287] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 09/16/2022] [Accepted: 09/18/2022] [Indexed: 12/03/2022] Open
Abstract
An effective response that combines prevention and treatment is still the most anticipated solution to the increasing incidence of antimicrobial resistance (AMR). As the phenomenon continues to evolve, AMR is driving an escalation of hard-to-treat infections and mortality rates. Over the years, bacteria have devised a variety of survival tactics to outwit the antibiotic’s effects, yet given their great adaptability, unexpected mechanisms are still to be discovered. Over-expression of efflux pumps (EPs) constitutes the leading strategy of bacterial resistance, and it is also a primary driver in the establishment of multidrug resistance (MDR). Extensive efforts are being made to develop antibiotic resistance breakers (ARBs) with the ultimate goal of re-sensitizing bacteria to medications to which they have become unresponsive. EP inhibitors (EPIs) appear to be the principal group of ARBs used to impair the efflux system machinery. Due to the high toxicity of synthetic EPIs, there is a growing interest in natural, safe, and innocuous ones, whereby plant extracts emerge to be excellent candidates. Besides EPIs, further alternatives are being explored including the development of nanoparticle carriers, biologics, and phage therapy, among others. What roles do EPs play in the occurrence of MDR? What weapons do we have to thwart EP-mediated resistance? What are the obstacles to their development? These are some of the core questions addressed in the present review.
Collapse
Affiliation(s)
- Armel Jackson Seukep
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 437004, China
- Department of Biomedical Sciences, Faculty of Health Sciences, University of Buea, Buea P.O. Box 63, Cameroon
- Sino-Africa Joint Research Center, Chinese Academy of Sciences, Wuhan 437004, China
- Innovation Academy for Drug Discovery and Development, Chinese Academy of Sciences, Shanghai 201203, China
| | - Helene Gueaba Mbuntcha
- Department of Biochemistry, Faculty of Science, University of Dschang, Dschang P.O. Box 67, Cameroon
| | - Victor Kuete
- Department of Biochemistry, Faculty of Science, University of Dschang, Dschang P.O. Box 67, Cameroon
| | - Yindi Chu
- State Key Laboratory of Medical Molecular Biology, Department of Microbiology and Parasitology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences/School of Basic Medicine, Peking Union Medical College, Beijing 100005, China
| | - Enguo Fan
- State Key Laboratory of Medical Molecular Biology, Department of Microbiology and Parasitology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences/School of Basic Medicine, Peking Union Medical College, Beijing 100005, China
- College of Life Sciences, Linyi University, Linyi 276005, China
- Correspondence: (E.F.); (M.-Q.G.)
| | - Ming-Quan Guo
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 437004, China
- Sino-Africa Joint Research Center, Chinese Academy of Sciences, Wuhan 437004, China
- Innovation Academy for Drug Discovery and Development, Chinese Academy of Sciences, Shanghai 201203, China
- Correspondence: (E.F.); (M.-Q.G.)
| |
Collapse
|
6
|
Briones AC, Lorca D, Cofre A, Cabezas CE, Krüger GI, Pardo-Esté C, Baquedano MS, Salinas CR, Espinoza M, Castro-Severyn J, Remonsellez F, Hidalgo AA, Morales EH, Saavedra CP. Genetic regulation of the ompX porin of Salmonella Typhimurium in response to hydrogen peroxide stress. Biol Res 2022; 55:8. [PMID: 35193678 PMCID: PMC8862304 DOI: 10.1186/s40659-022-00377-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 01/30/2022] [Indexed: 11/11/2022] Open
Abstract
Background Salmonella Typhimurium is a Gram-negative pathogen that causes a systemic disease in mice resembling typhoid fever. During its infective cycle, S. Typhimurium is phagocytized by macrophages and proliferates inside a Salmonella-containing vacuole where Salmonella is exposed and survives oxidative stress induced by H2O2 through modulation of gene expression. After exposure of Salmonella to H2O2, the expression of the porin-encoding gene ompX increases, as previously shown by microarray analysis. Expression of ompX mRNA is regulated at a post-transcriptional level by MicA and CyaR sRNAs in aerobiosis. In addition, sequence analysis predicts a site for OxyS sRNA in ompX mRNA. Results In this work we sought to evaluate the transcriptional and post-transcriptional regulation of ompX under H2O2 stress. We demonstrate that ompX expression is induced at the transcriptional level in S. Typhimurium under such conditions. Unexpectedly, an increase in ompX gene transcript and promoter activity after challenges with H2O2 does not translate into increased protein levels in the wild-type strain, suggesting that ompX mRNA is also regulated at a post-transcriptional level, at least under oxidative stress. In silico gene sequence analysis predicted that sRNAs CyaR, MicA, and OxyS could regulate ompX mRNA levels. Using rifampicin to inhibit mRNA expression, we show that the sRNAs (MicA, CyaR and OxyS) and the sRNA:mRNA chaperone Hfq positively modulate ompX mRNA levels under H2O2-induced stress in Salmonella during the exponential growth phase in Lennox broth. Conclusions Our results demonstrate that ompX mRNA is regulated in response to H2O2 by the sRNAs CyaR, MicA and OxyS is Salmonella Typhimurium. Supplementary Information The online version contains supplementary material available at 10.1186/s40659-022-00377-3.
Collapse
Affiliation(s)
- A C Briones
- Laboratorio de Microbiología Molecular, Departamento de Ciencias de La Vida, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - D Lorca
- Laboratorio de Microbiología Molecular, Departamento de Ciencias de La Vida, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - A Cofre
- Laboratorio de Microbiología Molecular, Departamento de Ciencias de La Vida, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - C E Cabezas
- Laboratorio de Microbiología Molecular, Departamento de Ciencias de La Vida, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - G I Krüger
- Laboratorio de Microbiología Molecular, Departamento de Ciencias de La Vida, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - C Pardo-Esté
- Laboratorio de Microbiología Molecular, Departamento de Ciencias de La Vida, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - M S Baquedano
- Laboratorio de Microbiología Molecular, Departamento de Ciencias de La Vida, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - C R Salinas
- Laboratorio de Microbiología Molecular, Departamento de Ciencias de La Vida, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - M Espinoza
- Laboratorio de Microbiología Molecular, Departamento de Ciencias de La Vida, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - J Castro-Severyn
- Laboratorio de Microbiología Aplicada Y Extremófilos, Facultad de Ingeniería Y Ciencias Geológicas, Universidad Católica 83 del Norte, Antofagasta, Chile
| | - F Remonsellez
- Laboratorio de Microbiología Aplicada Y Extremófilos, Facultad de Ingeniería Y Ciencias Geológicas, Universidad Católica 83 del Norte, Antofagasta, Chile.,Centro de Investigación Tecnológica del Agua en El Desierto (CEITSAZA), Universidad Católica del Norte, Antofagasta, Chile
| | - A A Hidalgo
- Laboratory of Molecular Pathogenesis and Antimicrobials, Escuela de Química Y Farmacia, Facultad de Medicina, Universidad Andres Bello, Santiago, Chile
| | - E H Morales
- Laboratorio de Microbiología Molecular, Departamento de Ciencias de La Vida, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - C P Saavedra
- Laboratorio de Microbiología Molecular, Departamento de Ciencias de La Vida, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile.
| |
Collapse
|
7
|
Gene Amplification Uncovers Large Previously Unrecognized Cryptic Antibiotic Resistance Potential in E. coli. Microbiol Spectr 2021; 9:e0028921. [PMID: 34756069 PMCID: PMC8579933 DOI: 10.1128/spectrum.00289-21] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The activation of unrecognized antibiotic resistance genes in the bacterial cell can give rise to antibiotic resistance without the need for major mutations or horizontal gene transfer. We hypothesize that bacteria harbor an extensive array of diverse cryptic genes that can be activated in response to antibiotics via adaptive resistance. To test this hypothesis, we developed a plasmid assay to randomly manipulate gene copy numbers in Escherichia coli cells and identify genes that conferred resistance when amplified. We then tested for cryptic resistance to 18 antibiotics and identified genes conferring resistance. E. coli could become resistant to 50% of the antibiotics tested, including chloramphenicol, d-cycloserine, polymyxin B, and 6 beta-lactam antibiotics, following this manipulation. Known antibiotic resistance genes comprised 13% of the total identified genes, where 87% were unclassified (cryptic) antibiotic resistance genes. These unclassified genes encoded cell membrane proteins, stress response/DNA repair proteins, transporters, and miscellaneous or hypothetical proteins. Stress response/DNA repair genes have a broad antibiotic resistance potential, as this gene class, in aggregate, conferred cryptic resistance to nearly all resistance-positive antibiotics. We found that antibiotics that are hydrophilic, those that are amphipathic, and those that inhibit the cytoplasmic membrane or cell wall biosynthesis were more likely to induce cryptic resistance in E. coli. This study reveals a diversity of cryptic genes that confer an antibiotic resistance phenotype when present in high copy number. Thus, our assay can identify potential novel resistance genes while also describing which antibiotics are prone to induce cryptic antibiotic resistance in E. coli. IMPORTANCE Predicting where new antibiotic resistance genes will rise is a challenge and is especially important when new antibiotics are developed. Adaptive resistance allows sensitive bacterial cells to become transiently resistant to antibiotics. This provides an opportune time for cells to develop more efficient resistance mechanisms, such as tolerance and permanent resistance to higher antibiotic concentrations. The biochemical diversity harbored within bacterial genomes may lead to the presence of genes that could confer resistance when timely activated. Therefore, it is crucial to understand adaptive resistance to identify potential resistance genes and prolong antibiotics. Here, we investigate cryptic resistance, an adaptive resistance mechanism, and identify unknown (cryptic) antibiotic resistance genes that confer resistance when amplified in a laboratory strain of E. coli. We also pinpoint antibiotic characteristics that are likely to induce cryptic resistance. This study may help detect novel antibiotic resistance genes and provide the foundation to help develop more effective antibiotics.
Collapse
|
8
|
Bystritskaya E, Chernysheva N, Stenkova A, Guzev K, Rakin A, Isaeva M. Differential Expression of Yersinia pseudotuberculosis General Porin Genes during Short- and Long-Term Antibiotic Stresses. Molecules 2021; 26:3956. [PMID: 34203552 PMCID: PMC8272246 DOI: 10.3390/molecules26133956] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 06/21/2021] [Accepted: 06/23/2021] [Indexed: 11/25/2022] Open
Abstract
Here, we investigated general porin regulation in Yersinia pseudotuberculosis 488, the causative agent of Far Eastern scarlet-like fever, in response to sublethal concentrations of antibiotics. We chose four antibiotics of different classes and measured gene expression using qRT-PCR and GFP reporter systems. Our data showed temporal regulation of the general porin genes ompF and ompC caused by antibiotic stress. The porin transcription initially decreased, providing early defensive response of the bacterium, while it returned to that of the untreated cells on prolonged antibiotic exposure. Unlike the major porin genes, the transcription of the alternative porin genes ompX and lamB was increased. Moreover, a short-term ompR- and marA-mediated porin regulation was observed. The main finding was a phenotypic heterogeneity of Y. pseudotuberculosis population manifested in variable porin gene expression under carbenicillin exposure. This may offer adaptive fitness advantages for a particular bacterial subpopulation.
Collapse
Affiliation(s)
- Evgeniya Bystritskaya
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch, Russian Academy of Sciences, 159, Pr. 100 Let Vladivostoku, 690022 Vladivostok, Russia; (E.B.); (N.C.); (K.G.)
| | - Nadezhda Chernysheva
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch, Russian Academy of Sciences, 159, Pr. 100 Let Vladivostoku, 690022 Vladivostok, Russia; (E.B.); (N.C.); (K.G.)
| | - Anna Stenkova
- School of Biomedicine, Far Eastern Federal University, 8 Sukhanova St., 690090 Vladivostok, Russia;
| | - Konstantin Guzev
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch, Russian Academy of Sciences, 159, Pr. 100 Let Vladivostoku, 690022 Vladivostok, Russia; (E.B.); (N.C.); (K.G.)
| | - Alexander Rakin
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute for Bacterial Infections and Zoonoses, Naumburger Str. 96a, D-07743 Jena, Germany;
| | - Marina Isaeva
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch, Russian Academy of Sciences, 159, Pr. 100 Let Vladivostoku, 690022 Vladivostok, Russia; (E.B.); (N.C.); (K.G.)
- School of Biomedicine, Far Eastern Federal University, 8 Sukhanova St., 690090 Vladivostok, Russia;
| |
Collapse
|
9
|
Zhang Z, Ryoo D, Balusek C, Acharya A, Rydmark MO, Linke D, Gumbart JC. Inward-facing glycine residues create sharp turns in β-barrel membrane proteins. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183662. [PMID: 34097860 DOI: 10.1016/j.bbamem.2021.183662] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 04/15/2021] [Accepted: 05/17/2021] [Indexed: 11/29/2022]
Abstract
The transmembrane region of outer-membrane proteins (OMPs) of Gram-negative bacteria are almost exclusively β-barrels composed of between 8 and 26 β-strands. To explore the relationship between β-barrel size and shape, we modeled and simulated engineered variants of the Escherichia coli protein OmpX with 8, 10, 12, 14, and 16 β-strands. We found that while smaller barrels maintained a roughly circular shape, the 16-stranded variant developed a flattened cross section. This flat cross section impeded its ability to conduct ions, in agreement with previous experimental observations. Flattening was determined to arise from the presence of inward-facing glycines at sharp turns in the β-barrel. An analysis of all simulations revealed that glycines, on average, make significantly smaller angles with residues on neighboring strands than all other amino acids, including alanine, and create sharp turns in β-barrel cross sections. This observation was generalized to 119 unique structurally resolved OMPs. We also found that the fraction of glycines in β-barrels decreases as the strand number increases, suggesting an evolutionary role for the addition or removal of glycine in OMP sequences.
Collapse
Affiliation(s)
- Zijian Zhang
- School of Physics, Georgia Institute of Technology, Atlanta, GA 30313, United States of America
| | - David Ryoo
- Interdisciplinary Bioengineering Graduate Program, Georgia Institute of Technology, Atlanta, GA 30332, United States of America
| | - Curtis Balusek
- School of Physics, Georgia Institute of Technology, Atlanta, GA 30313, United States of America
| | - Atanu Acharya
- School of Physics, Georgia Institute of Technology, Atlanta, GA 30313, United States of America
| | | | - Dirk Linke
- Department of Biosciences, University of Oslo, Oslo, Norway
| | - James C Gumbart
- School of Physics, Georgia Institute of Technology, Atlanta, GA 30313, United States of America.
| |
Collapse
|
10
|
AlMatar M, Albarri O, Makky EA, Köksal F. Efflux pump inhibitors: new updates. Pharmacol Rep 2020; 73:1-16. [PMID: 32946075 DOI: 10.1007/s43440-020-00160-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 09/04/2020] [Accepted: 09/07/2020] [Indexed: 12/17/2022]
Abstract
The discovery of antibiotics ought to have ended the issue of bacterial infections, but this was not the case as it has led to the evolution of various mechanisms of bacterial resistance against various antibiotics. The efflux pump remains one of the mechanisms through which organisms develop resistance against antibiotics; this is because organisms can extrude most of the clinically relevant antibiotics from the interior cell environment to the exterior environment via the efflux pumps. Efflux pumps are thought to contribute significantly to biofilm formation as highlighted by various studies. Therefore, the inhibition of these efflux pumps can be a potential way of improving the activity of antibiotics, particularly now that the discovery of novel antibiotics is becoming tedious. Efflux pump inhibitors (EPIs) are molecules that can inhibit efflux pumps; they have been considered potential therapeutic agents for rejuvenating the activity of antibiotics that have already lost their activity against bacteria. However, studies are yet to determine the specific substrates for such pumps; the effect of altered efflux activity of these pumps on biofilm formation is still being investigated. A clear knowledge of the involvement of efflux pumps in biofilm development could aid in developing new agents that can interfere with their function and help to prevent biofilms formation; thereby, improving the outcome of treatment strategies. This review focuses on the novel update of EPIs and discusses the evidence of the roles of efflux pumps in biofilm formation; the potential approaches towards overcoming the increasing problem of biofilm-based infections are also discussed.
Collapse
Affiliation(s)
- Manaf AlMatar
- Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang (UMP), 26300, Gambang, Kuantan, Malaysia.
| | - Osman Albarri
- Department of Biotechnology, Institute of Natural and Applied Sciences (Fen Bilimleri Enstitüsü), Çukurova University, Adana, Turkey
| | - Essam A Makky
- Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang (UMP), 26300, Gambang, Kuantan, Malaysia.
| | - Fatih Köksal
- Department of Medical Microbiology, Faculty of Medicine, Çukurova University, Adana, Turkey
| |
Collapse
|
11
|
Mishra M, Panda S, Barik S, Sarkar A, Singh DV, Mohapatra H. Antibiotic Resistance Profile, Outer Membrane Proteins, Virulence Factors and Genome Sequence Analysis Reveal Clinical Isolates of Enterobacter Are Potential Pathogens Compared to Environmental Isolates. Front Cell Infect Microbiol 2020; 10:54. [PMID: 32154188 PMCID: PMC7047878 DOI: 10.3389/fcimb.2020.00054] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Accepted: 01/31/2020] [Indexed: 01/02/2023] Open
Abstract
Outer membrane proteins (OMPs) of gram-negative bacteria play an important role in mediating antibacterial resistance, bacterial virulence and thus affect pathogenic ability of the bacteria. Over the years, prevalence of environmental antibiotic resistant organisms, their transmission to clinics and ability to transfer resistance genes, have been studied extensively. Nevertheless, how successful environmental bacteria can be in establishing as pathogenic bacteria under clinical setting, is less addressed. In the present study, we utilized an integrated approach of investigating the antibiotic resistance profile, presence of outer membrane proteins and virulence factors to understand extent of threat posed due to multidrug resistant environmental Enterobacter isolates. Also, we investigated clinical Enterobacter isolates and compared the results thereof. Results of the study showed that multidrug resistant environmental Enterobacter isolates lacked OmpC, lacked cell invasion abilities and exhibited low reactive oxygen species (ROS) production in neutrophils. In contrast, clinical isolates possessed OmpF, exhibited high invasive and adhesive property and produced higher amounts of ROS in neutrophils. These attributes indicated limited pathogenic potential of environmental Enterobacter isolates. Informations obtained from whole genome sequence of two representative bacterial isolates from environment (DL4.3) and clinical sources (EspIMS6) corroborated well with the observed results. Findings of the present study are significant as it highlights limited fitness of multidrug resistant environmental Enterobacter isolates.
Collapse
Affiliation(s)
- Mitali Mishra
- School of Biological Sciences, National Institute of Science Education and Research, HBNI, Bhubaneswar, India.,Homi Bhabha National Institute (HBNI), Mumbai, India
| | - Sasmita Panda
- Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India
| | - Susmita Barik
- Trident School of Biotech Sciences, Trident Academy of Creative and Technology, Bhubaneswar, India
| | - Arup Sarkar
- Trident School of Biotech Sciences, Trident Academy of Creative and Technology, Bhubaneswar, India
| | - Durg Vijai Singh
- Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India
| | - Harapriya Mohapatra
- School of Biological Sciences, National Institute of Science Education and Research, HBNI, Bhubaneswar, India.,Homi Bhabha National Institute (HBNI), Mumbai, India
| |
Collapse
|
12
|
Uddin MJ, Ma CJ, Kim JC, Ahn J. Proteomics-based discrimination of differentially expressed proteins in antibiotic-sensitive and antibiotic-resistant Salmonella Typhimurium, Klebsiella pneumoniae, and Staphylococcus aureus. Arch Microbiol 2019; 201:1259-1275. [PMID: 31240342 DOI: 10.1007/s00203-019-01693-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Revised: 06/06/2019] [Accepted: 06/13/2019] [Indexed: 01/25/2023]
Abstract
This study was designed to compare the differentially expressed proteins between antibiotic-sensitive and antibiotic-resistant Salmonella Typhimurium, Klebsiella pneumonia, and Staphylococcus aureus. The susceptibilities of wild-type (WT), ciprofloxacin (CIP) and/or oxacillin (OXA)-induced, and clinically isolated resistant (CCARM) S. Typhimurium (STWT, STCIP, and STCCARM), K. pneumoniae (KPWT, KPCIP, and KPCCARM), and S. aureus (SAWT, SACIP, SAOXA, and SACCARM) to antibiotics were determined using broth microdilution assay. STCIP was highly resistant to piperacillin (MIC > 512 μg/ml), KPCIP was resistant to chloramphenicol (128 μg/ml) and norfloxacin (16 μg/ml), SACIP was resistant to fluoroquinolones (32 μg/ml), and SAOXA was resistant to ceftriaxone (32 μg/ml). The protein profiles of antibiotic-sensitive and antibiotic-resistant strains were determined using 2-DE analysis followed by LC-MS/MS. The commonly expressed proteins of STWT-STCIP, STWT-STCCARM, KPWT-KPCIP, KPWT-KPCCARM, SAWT-SACIP, SAWT-SAOXA, and SAWT-SACCARM were 763, 677, 677, 469, 261, 259, and 226, respectively. The unique protein spots were observed 57 (6.5%), 80 (11.5%), and 68 (13.9%), respectively, for STCCARM, KPCCARM, and SACCARM. The highly up-regulated protein, PrsA (10-fold), was observed in STCIP resistant to ciprofloxacin (128-fold), levofloxacin (32-fold), norfloxacin (64-fold), and piperacillin (> 16-fold). The up-regulated proteins (YadC, FimA, and RplB) in KPCIP resistant to chloramphenicol (> 32-fold), ciprofloxacin (32-fold), levofloxacin (6-fold), norfloxacin (128-fold), and sparfloxacin (64-fold). AcrB and RpoB were up-regulated in SACCARM resistant to multiple antibiotics. The differentially expressed proteins were related to the antibiotic resistance of STWT, STCIP, STCCARM, KPWT, KPCIP, KPCCARM, SAWT, SACIP, SAOXA, and SACCARM. The resistance-associated proteins could be useful biomarkers for detecting antibiotic-resistant pathogens.
Collapse
Affiliation(s)
- Md Jalal Uddin
- Department of Medical Biomaterials Engineering and Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon, Gangwon, 24341, Republic of Korea
| | - Choong Je Ma
- Department of Medical Biomaterials Engineering and Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon, Gangwon, 24341, Republic of Korea
| | - Jin-Chul Kim
- Department of Medical Biomaterials Engineering and Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon, Gangwon, 24341, Republic of Korea
| | - Juhee Ahn
- Department of Medical Biomaterials Engineering and Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon, Gangwon, 24341, Republic of Korea.
| |
Collapse
|
13
|
Zhang J, Wang X, Suo X, Liu X, Liu B, Yuan M, Wang G, Liang C, Shi H. Cellular Response of Escherichia coli to Photocatalysis: Flagellar Assembly Variation and Beyond. ACS NANO 2019; 13:2004-2014. [PMID: 30721027 DOI: 10.1021/acsnano.8b08475] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Bacterial cells can be inactivated by external reactive oxygen species (ROS) produced by semiconductor photocatalysis. However, little is known about cellular responses to photocatalysis. For a better understanding of this issue, one strain of Escherichia coli ( E. coli, hereafter named as MT), which has an increased ability to metabolize carbon sources, was screened out from the wild-type (WT) E. coli K12 by repeated exposure to photocatalysis with palladium oxide modified nitrogen-doped titanium dioxide. In this study, transcriptome sequencing of the WT and MT strains that were exposed or unexposed to photocatalysis were carried out. Cellular responses to photocatalysis were inferred from the functions of genes whose transcripts were either increased or decreased. Upregulation of expression of bacterial flagellar assembly genes used for chemotaxis was detected in cells exposed to semilethal photocatalytic conditions of the WT E. coli. Increased capability to degrade superoxide radicals and decreased bacterial flagellar assembly and chemotaxis were observed in MT E. coli compared to WT cells. We conclude that the differences in motility and intracellular ROS between MT and WT are directly related to survivability of E. coli during exposure to photodisinfection.
Collapse
Affiliation(s)
- Jingtao Zhang
- Collaborative Innovation Centre of Food Production and Safety, Henan Key Laboratory of Cold Chain Food Quality and Safety Control, School of Food and Bioengineering , Zhengzhou University of Light Industry , Zhengzhou 450002 , China
| | - Xueying Wang
- Collaborative Innovation Centre of Food Production and Safety, Henan Key Laboratory of Cold Chain Food Quality and Safety Control, School of Food and Bioengineering , Zhengzhou University of Light Industry , Zhengzhou 450002 , China
| | - Xinying Suo
- Collaborative Innovation Centre of Food Production and Safety, Henan Key Laboratory of Cold Chain Food Quality and Safety Control, School of Food and Bioengineering , Zhengzhou University of Light Industry , Zhengzhou 450002 , China
| | - Xing Liu
- Collaborative Innovation Centre of Food Production and Safety, Henan Key Laboratory of Cold Chain Food Quality and Safety Control, School of Food and Bioengineering , Zhengzhou University of Light Industry , Zhengzhou 450002 , China
| | - Bingkun Liu
- School of Material and Chemical Engineering , Zhengzhou University of Light Industry , Zhengzhou 450002 , China
| | - Mingming Yuan
- Collaborative Innovation Centre of Food Production and Safety, Henan Key Laboratory of Cold Chain Food Quality and Safety Control, School of Food and Bioengineering , Zhengzhou University of Light Industry , Zhengzhou 450002 , China
| | - Guanglu Wang
- Collaborative Innovation Centre of Food Production and Safety, Henan Key Laboratory of Cold Chain Food Quality and Safety Control, School of Food and Bioengineering , Zhengzhou University of Light Industry , Zhengzhou 450002 , China
| | - Chengzhen Liang
- Biotechnology Research Institute , Chinese Academy of Agricultural Sciences , Beijing 100081 , China
| | - Hengzhen Shi
- School of Material and Chemical Engineering , Zhengzhou University of Light Industry , Zhengzhou 450002 , China
| |
Collapse
|
14
|
Abstract
The transport of small molecules across membranes is essential for the import of nutrients and other energy sources into the cell and, for the export of waste and other potentially harmful byproducts out of the cell. While hydrophobic molecules are permeable to membranes, ions and other small polar molecules require transport via specialized membrane transport proteins . The two major classes of membrane transport proteins are transporters and channels. With our focus here on porins-major class of non-specific diffusion channel proteins , we will highlight some recent structural biology reports and functional assays that have substantially contributed to our understanding of the mechanism that mediates uptake of small molecules, including antibiotics, across the outer membrane of Enterobacteriaceae . We will also review advances in the regulation of porin expression and porin biogenesis and discuss these pathways as new therapeutic targets.
Collapse
Affiliation(s)
- Muriel Masi
- UMR_MD1, Inserm U1261, IRBA, Membranes et Cibles Thérapeutiques, Facultés de Médecine et de Pharmacie, Aix-Marseille Université, Marseille, France
| | | | - Jean-Marie Pagès
- UMR_MD1, Inserm U1261, IRBA, Membranes et Cibles Thérapeutiques, Facultés de Médecine et de Pharmacie, Aix-Marseille Université, Marseille, France.
| |
Collapse
|
15
|
Jousset AB, Rosinski-Chupin I, Takissian J, Glaser P, Bonnin RA, Naas T. Transcriptional Landscape of a bla KPC-2 Plasmid and Response to Imipenem Exposure in Escherichia coli TOP10. Front Microbiol 2018; 9:2929. [PMID: 30559731 PMCID: PMC6286996 DOI: 10.3389/fmicb.2018.02929] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 11/14/2018] [Indexed: 12/15/2022] Open
Abstract
The diffusion of KPC-2 carbapenemase is closely related to the spread of Klebsiella pneumoniae of the clonal-group 258 and linked to IncFIIK plasmids. Little is known about the biology of multi-drug resistant plasmids and the reasons of their successful dissemination. Using E. coli TOP10 strain harboring a multi-replicon IncFIIK-IncFIB blaKPC−2-gene carrying plasmid pBIC1a from K. pneumoniae ST-258 clinical isolate BIC-1, we aimed to identify basal gene expression and the effects of imipenem exposure using whole transcriptome approach by RNA sequencing (RNA-Seq). Independently of the antibiotic pressure, most of the plasmid-backbone genes were expressed at low levels. The most expressed pBIC1a genes were involved in antibiotic resistance (blaKPC−2, blaTEM and aph(3′)-I), in plasmid replication and conjugation, or associated to mobile elements. After antibiotic exposure, 34% of E. coli (pBIC1a) genome was differentially expressed. Induction of oxidative stress response was evidenced, with numerous upregulated genes of the SoxRS/OxyR oxydative stress regulons, the Fur regulon (for iron uptake machinery), and IscR regulon (for iron sulfur cluster synthesis). Nine genes carried by pBIC1a were up-regulated, including the murein DD-endopeptidase mepM and the copper resistance operon. Despite the presence of a carbapenemase, we observed a major impact on E. coli (pBIC1a) whole transcriptome after imipenem exposure, but no effect on the level of transcription of antimicrobial resistance genes. We describe adaptive responses of E. coli to imipenem-induced stress, and identified plasmid-encoded genes that could be involved in resistance to stressful environments.
Collapse
Affiliation(s)
- Agnès B Jousset
- Department of Bacteriology-Parasitology-Hygiene, Bicêtre Hospital, Assistance Publique-Hôpitaux de Paris, Le Kremlin-Bicêtre, France.,Associated French National Reference Center for Antibiotic Resistance, Le Kremlin-Bicêtre, France.,EA7361 "Structure, dynamic, function and expression of broad spectrum β-lactamases", Faculty of Medicine, Paris-Sud University, Le Kremlin-Bicêtre, France.,Joint Research Unit Evolution and Ecology of Resistance to Antibiotics, Institut Pasteur-APHP-University Paris Sud, Paris, France
| | - Isabelle Rosinski-Chupin
- Joint Research Unit Evolution and Ecology of Resistance to Antibiotics, Institut Pasteur-APHP-University Paris Sud, Paris, France.,CNRS, UMRS 3525, Paris, France
| | - Julie Takissian
- EA7361 "Structure, dynamic, function and expression of broad spectrum β-lactamases", Faculty of Medicine, Paris-Sud University, Le Kremlin-Bicêtre, France.,Joint Research Unit Evolution and Ecology of Resistance to Antibiotics, Institut Pasteur-APHP-University Paris Sud, Paris, France
| | - Philippe Glaser
- Joint Research Unit Evolution and Ecology of Resistance to Antibiotics, Institut Pasteur-APHP-University Paris Sud, Paris, France.,CNRS, UMRS 3525, Paris, France
| | - Rémy A Bonnin
- Associated French National Reference Center for Antibiotic Resistance, Le Kremlin-Bicêtre, France.,EA7361 "Structure, dynamic, function and expression of broad spectrum β-lactamases", Faculty of Medicine, Paris-Sud University, Le Kremlin-Bicêtre, France.,Joint Research Unit Evolution and Ecology of Resistance to Antibiotics, Institut Pasteur-APHP-University Paris Sud, Paris, France
| | - Thierry Naas
- Department of Bacteriology-Parasitology-Hygiene, Bicêtre Hospital, Assistance Publique-Hôpitaux de Paris, Le Kremlin-Bicêtre, France.,Associated French National Reference Center for Antibiotic Resistance, Le Kremlin-Bicêtre, France.,EA7361 "Structure, dynamic, function and expression of broad spectrum β-lactamases", Faculty of Medicine, Paris-Sud University, Le Kremlin-Bicêtre, France.,Joint Research Unit Evolution and Ecology of Resistance to Antibiotics, Institut Pasteur-APHP-University Paris Sud, Paris, France
| |
Collapse
|
16
|
Molecular mechanisms of polymyxin resistance and detection of mcr genes. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub 2018; 163:28-38. [PMID: 30439931 DOI: 10.5507/bp.2018.070] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 10/26/2018] [Indexed: 12/12/2022] Open
Abstract
Antibiotic resistance is an ever-increasing global problem. Major commercial antibiotics often fail to fight common bacteria, and some pathogens have become multi-resistant. Polymyxins are potent bactericidal antibiotics against gram-negative bacteria. Known resistance to polymyxin includes intrinsic, mutational and adaptive mechanisms, with the recently described horizontally acquired resistance mechanisms. In this review, we present several strategies for bacteria to develop enhanced resistance to polymyxins, focusing on changes in the outer membrane, efflux and other resistance determinants. Better understanding of the genes involved in polymyxin resistance may pave the way for the development of new and effective antimicrobial agents. We also report novel in silico tested primers for PCR assay that may be able distinguish colistin-resistant isolates carrying the plasmid-encoded mcr genes and will assist in combating the spread of colistin resistance in bacteria.
Collapse
|
17
|
Li B, Huang Q, Cui A, Liu X, Hou B, Zhang L, Liu M, Meng X, Li S. Overexpression of Outer Membrane Protein X (OmpX) Compensates for the Effect of TolC Inactivation on Biofilm Formation and Curli Production in Extraintestinal Pathogenic Escherichia coli (ExPEC). Front Cell Infect Microbiol 2018; 8:208. [PMID: 29988395 PMCID: PMC6024092 DOI: 10.3389/fcimb.2018.00208] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Accepted: 06/05/2018] [Indexed: 11/24/2022] Open
Abstract
Our previous study showed that the inactivation of the efflux pump TolC could abolish biofilm formation and curli production of extraintestinal pathogenic Escherichia coli (ExPEC) strain PPECC42 under hyper-osmotic conditions. In this study we investigated the role of OmpX in biofilm formation and curli production of ExPEC PPECC42. Our data showed that OmpX disruption or overexpression didn't significantly affect the biofilm formation and curli production of the wild-type strain. However, in the tolC-deleted mutant, overexpressing OmpX suppressed the effect of TolC inactivation on ExPEC biofilm formation and curli production under hyper-osmotic growth conditions. Real-time qRT-PCR confirmed that OmpX overexpression affected curli production by regulating the transcription of the curli biosynthesis-related genes in the ΔtolC strain. Our findings suggest that OmpX is involved in biofilm formation and curli production.
Collapse
Affiliation(s)
- Binyou Li
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Qi Huang
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Ailian Cui
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Xueling Liu
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Bo Hou
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Liyuan Zhang
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Mei Liu
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Xianrong Meng
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Shaowen Li
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| |
Collapse
|
18
|
Dam S, Pagès JM, Masi M. Stress responses, outer membrane permeability control and antimicrobial resistance in Enterobacteriaceae. MICROBIOLOGY-SGM 2018; 164:260-267. [PMID: 29458656 DOI: 10.1099/mic.0.000613] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Bacteria have evolved several strategies to survive a myriad of harmful conditions in the environment and in hosts. In Gram-negative bacteria, responses to nutrient limitation, oxidative or nitrosative stress, envelope stress, exposure to antimicrobials and other growth-limiting stresses have been linked to the development of antimicrobial resistance. This results from the activation of protective changes to cell physiology (decreased outer membrane permeability), resistance transporters (drug efflux pumps), resistant lifestyles (biofilms, persistence) and/or resistance mutations (target mutations, production of antibiotic modification/degradation enzymes). In targeting and interfering with essential physiological mechanisms, antimicrobials themselves are considered as stresses to which protective responses have also evolved. In this review, we focus on envelope stress responses that affect the expression of outer membrane porins and their impact on antimicrobial resistance. We also discuss evidences that indicate the role of antimicrobials as signaling molecules in activating envelope stress responses.
Collapse
Affiliation(s)
- Sushovan Dam
- UMR_MD-1, Aix-Marseille Univ. & IRBA, 27 Boulevard Jean Moulin, 13005 Marseille, France
| | - Jean-Marie Pagès
- UMR_MD-1, Aix-Marseille Univ. & IRBA, 27 Boulevard Jean Moulin, 13005 Marseille, France
| | - Muriel Masi
- UMR_MD-1, Aix-Marseille Univ. & IRBA, 27 Boulevard Jean Moulin, 13005 Marseille, France
| |
Collapse
|
19
|
Michalik M, Orwick-Rydmark M, Habeck M, Alva V, Arnold T, Linke D. An evolutionarily conserved glycine-tyrosine motif forms a folding core in outer membrane proteins. PLoS One 2017; 12:e0182016. [PMID: 28771529 PMCID: PMC5542473 DOI: 10.1371/journal.pone.0182016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 07/11/2017] [Indexed: 12/02/2022] Open
Abstract
An intimate interaction between a pair of amino acids, a tyrosine and glycine on neighboring β-strands, has been previously reported to be important for the structural stability of autotransporters. Here, we show that the conservation of this interacting pair extends to nearly all major families of outer membrane β-barrel proteins, which are thought to have originated through duplication events involving an ancestral ββ hairpin. We analyzed the function of this motif using the prototypical outer membrane protein OmpX. Stopped-flow fluorescence shows that two folding processes occur in the millisecond time regime, the rates of which are reduced in the tyrosine mutant. Folding assays further demonstrate a reduction in the yield of folded protein for the mutant compared to the wild-type, as well as a reduction in thermal stability. Taken together, our data support the idea of an evolutionarily conserved ‘folding core’ that affects the folding, membrane insertion, and thermal stability of outer membrane protein β-barrels.
Collapse
Affiliation(s)
- Marcin Michalik
- Department of Biosciences, University of Oslo, Oslo, Norway
- Previous affiliation: Department of Protein Evolution, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | | | - Michael Habeck
- Statistical inverse problems in Biophysics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
- Felix Bernstein Institute for Mathematical Statistics in the Biosciences, University of Göttingen, Göttingen, Germany
| | - Vikram Alva
- Department of Protein Evolution, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Thomas Arnold
- Previous affiliation: Department of Protein Evolution, Max Planck Institute for Developmental Biology, Tübingen, Germany
- Boehringer Ingelheim Veterinary Research Center, Hannover, Germany
| | - Dirk Linke
- Department of Biosciences, University of Oslo, Oslo, Norway
- Previous affiliation: Department of Protein Evolution, Max Planck Institute for Developmental Biology, Tübingen, Germany
- * E-mail:
| |
Collapse
|
20
|
Mahmood HY, Jamshidi S, Sutton JM, Rahman KM. Current Advances in Developing Inhibitors of Bacterial Multidrug Efflux Pumps. Curr Med Chem 2016; 23:1062-81. [PMID: 26947776 PMCID: PMC5425656 DOI: 10.2174/0929867323666160304150522] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Revised: 01/27/2016] [Accepted: 03/10/2016] [Indexed: 01/30/2023]
Abstract
Antimicrobial resistance represents a significant challenge to future healthcare provision. An acronym ESKAPEE has been derived from the names of the organisms recognised as the major threats although there are a number of other organisms, notably Neisseria gonorrhoeae, that have become equally challenging to treat in the clinic. These pathogens are characterised by the ability to rapidly develop and/or acquire resistance mechanisms in response to exposure to different antimicrobial agents. A key part of the armoury of these pathogens is a series of efflux pumps, which effectively exclude or reduce the intracellular concentration of a large number of antibiotics, making the pathogens significantly more resistant. These efflux pumps are the topic of considerable interest, both from the perspective of basic understanding of efflux pump function, and its role in drug resistance but also as targets for the development of novel adjunct therapies. The necessity to overcome antimicrobial resistance has encouraged investigations into the characterisation of resistance-modifying efflux pump inhibitors to block the mechanisms of drug extrusion, thereby restoring antibacterial susceptibility and returning existing antibiotics into the clinic. A greater understanding of drug recognition and transport by multidrug efflux pumps is needed to develop clinically useful inhibitors, given the breadth of molecules that can be effluxed by these systems. This review discusses different bacterial EPIs originating from both natural source and chemical synthesis and examines the challenges to designing successful EPIs that can be useful against multidrug resistant bacteria.
Collapse
Affiliation(s)
| | | | | | - Khondaker M Rahman
- Institute of Pharmaceutical Science, King's College London, Britannia House, London SE1 1DB, UK.
| |
Collapse
|
21
|
Gokgoz NB, Akbulut BS. Proteomics Evidence for the Activity of the Putative Antibacterial Plant Alkaloid (-)-Roemerine: Mainstreaming Omics-Guided Drug Discovery. OMICS-A JOURNAL OF INTEGRATIVE BIOLOGY 2016; 19:478-89. [PMID: 26230533 DOI: 10.1089/omi.2015.0056] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Discovery of new antibacterials with novel mechanisms is important to counteract the ingenious resistance mechanisms of bacteria. In this connection, omics-guided drug discovery offers a rigorous method in the quest of new antibacterials. (-)-Roemerine is a plant alkaloid that has been reported to possess putative antibacterial activity against Escherichia coli, Bacillus subtilis, and Salmonella typhimurium. The aim of the present study was to characterize the activity of (-)-roemerine in Escherichia coli TB1 using proteomics tools. With (-)-roemerine treatment, we found limited permeability through the outer membrane and repression of transport proteins involved in carbohydrate metabolism, resulting in poor carbon source availability. The shortfall of intracellular carbon sources in turn led to impaired cell growth. The reduction in the abundance of proteins related to translational machinery, amino acid biosynthesis, and metabolism was accompanied by a nutrient-limited state. The latter finding could suggest a metabolic shutdown in E. coli cells. High osmolarity was clearly not one of the reasons of bacterial death by (-)-roemerine. These observations collectively attest to the promise of plant omics and profiling of putative drug candidates using proteomics tools. Omics-guided drug discovery deserves greater attention in mainstream pharmacology so as to better understand the plants' medicinal potentials.
Collapse
|
22
|
Catel-Ferreira M, Marti S, Guillon L, Jara L, Coadou G, Molle V, Bouffartigues E, Bou G, Shalk I, Jouenne T, Vila-Farrés X, Dé E. The outer membrane porin OmpW of Acinetobacter baumannii is involved in iron uptake and colistin binding. FEBS Lett 2016; 590:224-31. [PMID: 26823169 DOI: 10.1002/1873-3468.12050] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 12/10/2015] [Indexed: 11/07/2022]
Abstract
This study was undertaken to characterize functions of the outer membrane protein OmpW, which potentially contributes to the development of colistin- and imipenem-resistance in Acinetobacter baumannii. Reconstitution of OmpW in artificial lipid bilayers showed that it forms small channels (23 pS in 1 m KCl) and markedly interacts with iron and colistin, but not with imipenem. In vivo, (55) Fe uptake assays comparing the behaviours of ΔompW mutant and wild-type strains confirmed a role for OmpW in A. baumannii iron homeostasis. However, the loss of OmpW expression did not have an impact on A. baumannii susceptibilities to colistin or imipenem.
Collapse
Affiliation(s)
- Manuella Catel-Ferreira
- CNRS UMR 6270 & FR3038, Normandie Univ, Laboratoire Polymères, Biopolymères & Surfaces, Université de Rouen, Mont Saint Aignan, France
| | - Sara Marti
- CNRS UMR 6270 & FR3038, Normandie Univ, Laboratoire Polymères, Biopolymères & Surfaces, Université de Rouen, Mont Saint Aignan, France.,Center for International Health Research, CRESIB, Hospital Clínic, University of Barcelona, Spain
| | - Laurent Guillon
- UMR 7242, Université de Strasbourg-CNRS, ESBS, Illkirch, France
| | - Luis Jara
- Departament de Genètica i Microbiologia, Facultat de Biociències, Universitat Autònoma de Barcelona, Spain
| | - Gaël Coadou
- COBRA-CNRS, Laboratoire de RMN et Modélisation moléculaire, UMR 6014 & FR3038 CNRS, Université de Rouen, Mont Saint Aignan, France
| | - Virginie Molle
- Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Universités de Montpellier II et I, CNRS; UMR 5235, Montpellier Cedex 05, France
| | - Emeline Bouffartigues
- Laboratoire de Microbiologie Signaux et Micro-Environnement (LMSM) EA 4312, Université de Rouen, Evreux, France
| | - German Bou
- Servicio de Microbiología-INIBIC, Complejo Hospitalario Universitario A Coruña (CHUAC), Spain
| | - Isabelle Shalk
- UMR 7242, Université de Strasbourg-CNRS, ESBS, Illkirch, France
| | - Thierry Jouenne
- CNRS UMR 6270 & FR3038, Normandie Univ, Laboratoire Polymères, Biopolymères & Surfaces, Université de Rouen, Mont Saint Aignan, France
| | - Xavier Vila-Farrés
- Center for International Health Research, CRESIB, Hospital Clínic, University of Barcelona, Spain
| | - Emmanuelle Dé
- CNRS UMR 6270 & FR3038, Normandie Univ, Laboratoire Polymères, Biopolymères & Surfaces, Université de Rouen, Mont Saint Aignan, France
| |
Collapse
|
23
|
Pinet E, Franceschi C, Davin-Regli A, Zambardi G, Pagès JM. Role of the culture medium in porin expression and piperacillin-tazobactam susceptibility in Escherichia coli. J Med Microbiol 2015; 64:1305-1314. [PMID: 26242994 DOI: 10.1099/jmm.0.000152] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The continuing emergence of the multidrug resistance phenotype in Gram-negative bacteria makes the development of rapid susceptibility tests mandatory. To achieve this goal, proprietary specific media for bacterial growth can be used but may have some adverse effects. In this study, we dissected the role of media on porin, efflux pump and β-lactamase expression. Depending on the medium used, we observed a change in piperacillin-tazobactam susceptibility for some isolates, such as increases in MIC values. No significant alteration in efflux activity or in β-lactamase production was detected after changing the incubation medium. The ratio of piperacillinase:nitrocefinase showed no specific alteration, indicating that the various media did not affect significantly the relative enzymic affinity for the substrates. In contrast, osmotic variation was able to modulate both porin expression and OmpC : OmpF balance, thus modulating the antibiotic uptake. This study suggests that porin expression may be impacted by a susceptibility testing medium, which may modify the antibiotic diffusion into the bacteria, thus affecting MIC results.
Collapse
Affiliation(s)
- Elizabeth Pinet
- UMR-MD-1, Aix-Marseille Université, IRBA, Transporteurs Membranaires, Chimiorésistance et Drug Design, Marseille, France
| | | | - Anne Davin-Regli
- UMR-MD-1, Aix-Marseille Université, IRBA, Transporteurs Membranaires, Chimiorésistance et Drug Design, Marseille, France
| | - Gilles Zambardi
- R&D Microbiology Innovation, bioMérieux, La Balme les Grottes, France
| | - Jean-Marie Pagès
- UMR-MD-1, Aix-Marseille Université, IRBA, Transporteurs Membranaires, Chimiorésistance et Drug Design, Marseille, France
| |
Collapse
|
24
|
Mouammine A, Lanois A, Pagès S, Lafay B, Molle V, Canova M, Girard PA, Duvic B, Givaudan A, Gaudriault S. Ail and PagC-related proteins in the entomopathogenic bacteria of Photorhabdus genus. PLoS One 2014; 9:e110060. [PMID: 25333642 PMCID: PMC4198210 DOI: 10.1371/journal.pone.0110060] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 09/07/2014] [Indexed: 01/14/2023] Open
Abstract
Among pathogenic Enterobacteriaceae, the proteins of the Ail/OmpX/PagC family form a steadily growing family of outer membrane proteins with diverse biological properties, potentially involved in virulence such as human serum resistance, adhesion and entry into eukaryotic culture cells. We studied the proteins Ail/OmpX/PagC in the bacterial Photorhabdus genus. The Photorhabdus bacteria form symbiotic complexes with nematodes of Heterorhabditis species, associations which are pathogenic to insect larvae. Our phylogenetic analysis indicated that in Photorhabdus asymbiotica and Photorhabdus luminescens only Ail and PagC proteins are encoded. The genomic analysis revealed that the Photorhabdus ail and pagC genes were present in a unique copy, except two ail paralogs from P. luminescens. These genes, referred to as ail1Pl and ail2Pl, probably resulted from a recent tandem duplication. Surprisingly, only ail1Pl expression was directly controlled by PhoPQ and low external Mg2+ conditions. In P. luminescens, the magnesium-sensing two-component regulatory system PhoPQ regulates the outer membrane barrier and is required for pathogenicity against insects. In order to characterize Ail functions in Photorhabdus, we showed that only ail2Pl and pagCPl had the ability, when expressed into Escherichia coli, to confer resistance to complement in human serum. However no effect in resistance to antimicrobial peptides was found. Thus, the role of Ail and PagC proteins in Photorhabdus life cycle is discussed.
Collapse
Affiliation(s)
- Annabelle Mouammine
- INRA, UMR Diversité, Génomes et Interactions Microorganismes-Insectes (DGIMI), Montpellier, France
- Université Montpellier 2, UMR Diversité, Génomes et Interactions Microorganismes-Insectes (DGIMI), Montpellier, France
| | - Anne Lanois
- INRA, UMR Diversité, Génomes et Interactions Microorganismes-Insectes (DGIMI), Montpellier, France
- Université Montpellier 2, UMR Diversité, Génomes et Interactions Microorganismes-Insectes (DGIMI), Montpellier, France
| | - Sylvie Pagès
- INRA, UMR Diversité, Génomes et Interactions Microorganismes-Insectes (DGIMI), Montpellier, France
- Université Montpellier 2, UMR Diversité, Génomes et Interactions Microorganismes-Insectes (DGIMI), Montpellier, France
| | - Bénédicte Lafay
- Université de Lyon, Écully, France
- CNRS, UMR5005 - Laboratoire Ampère, École Centrale de Lyon, Écully, France
| | - Virginie Molle
- Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Universités de Montpellier 2 et 1, CNRS, UMR 5235, Montpellier, France
| | - Marc Canova
- Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Universités de Montpellier 2 et 1, CNRS, UMR 5235, Montpellier, France
| | - Pierre-Alain Girard
- INRA, UMR Diversité, Génomes et Interactions Microorganismes-Insectes (DGIMI), Montpellier, France
- Université Montpellier 2, UMR Diversité, Génomes et Interactions Microorganismes-Insectes (DGIMI), Montpellier, France
| | - Bernard Duvic
- INRA, UMR Diversité, Génomes et Interactions Microorganismes-Insectes (DGIMI), Montpellier, France
- Université Montpellier 2, UMR Diversité, Génomes et Interactions Microorganismes-Insectes (DGIMI), Montpellier, France
| | - Alain Givaudan
- INRA, UMR Diversité, Génomes et Interactions Microorganismes-Insectes (DGIMI), Montpellier, France
- Université Montpellier 2, UMR Diversité, Génomes et Interactions Microorganismes-Insectes (DGIMI), Montpellier, France
| | - Sophie Gaudriault
- INRA, UMR Diversité, Génomes et Interactions Microorganismes-Insectes (DGIMI), Montpellier, France
- Université Montpellier 2, UMR Diversité, Génomes et Interactions Microorganismes-Insectes (DGIMI), Montpellier, France
- * E-mail:
| |
Collapse
|
25
|
Planchard N, Point É, Dahmane T, Giusti F, Renault M, Le Bon C, Durand G, Milon A, Guittet É, Zoonens M, Popot JL, Catoire LJ. The use of amphipols for solution NMR studies of membrane proteins: advantages and constraints as compared to other solubilizing media. J Membr Biol 2014; 247:827-42. [PMID: 24676477 DOI: 10.1007/s00232-014-9654-z] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Accepted: 03/07/2014] [Indexed: 01/24/2023]
Abstract
Solution-state nuclear magnetic resonance studies of membrane proteins are facilitated by the increased stability that trapping with amphipols confers to most of them as compared to detergent solutions. They have yielded information on the state of folding of the proteins, their areas of contact with the polymer, their dynamics, water accessibility, and the structure of protein-bound ligands. They benefit from the diversification of amphipol chemical structures and the availability of deuterated amphipols. The advantages and constraints of working with amphipols are discussed and compared to those associated with other non-conventional environments, such as bicelles and nanodiscs.
Collapse
Affiliation(s)
- Noelya Planchard
- Laboratoire de Biologie Physico-Chimique des Protéines Membranaires, Institut de Biologie Physico-Chimique (FRC 550), UMR 7099, CNRS, Université Paris 7, 13 rue Pierre et Marie Curie, 75005, Paris, France
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Amaral L, Martins A, Spengler G, Molnar J. Efflux pumps of Gram-negative bacteria: what they do, how they do it, with what and how to deal with them. Front Pharmacol 2014; 4:168. [PMID: 24427138 PMCID: PMC3879458 DOI: 10.3389/fphar.2013.00168] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 12/16/2013] [Indexed: 11/20/2022] Open
Abstract
This review discusses the relationship of the efflux pump (EP) system of Gram-negative bacteria to other antibiotic resistance mechanisms of the bacterium such as quorum sensing, biofilms, two component regulons, etc. The genetic responses of a Gram-negative to an antibiotic that render it immune to an antibiotic are also discussed. Lastly, the methods that have been developed for the identification of bacteria that over-express their EP system are presented in detail. Phenothiazines are well-known antipsychotic drugs with reported activity against bacterial EPs and other ancillary antibiotic mechanisms of the organism. Therefore these compounds will also be discussed.
Collapse
Affiliation(s)
- Leonard Amaral
- Travel Medicine of the Centro de Malária e Doenças Tropicais, Institute of Hygiene and Tropical Medicine, Universidade Nova de Lisboa Lisbon, Portugal ; Institute of Medical Microbiology and Immunobiology, University of Szeged Szeged, Hungary
| | - Ana Martins
- Institute of Medical Microbiology and Immunobiology, University of Szeged Szeged, Hungary ; Unit of Parasitology and Medical Microbiology, Institute of Hygiene and Tropical Medicine, Universidade Nova de Lisboa Lisbon, Portugal
| | - Gabriella Spengler
- Institute of Medical Microbiology and Immunobiology, University of Szeged Szeged, Hungary
| | - Joseph Molnar
- Institute of Medical Microbiology and Immunobiology, University of Szeged Szeged, Hungary
| |
Collapse
|
27
|
Carone BR, Xu T, Murphy KC, Marinus MG. High incidence of multiple antibiotic resistant cells in cultures of in enterohemorrhagic Escherichia coli O157:H7. Mutat Res 2013; 759:1-8. [PMID: 24361397 DOI: 10.1016/j.mrfmmm.2013.11.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 11/06/2013] [Accepted: 11/26/2013] [Indexed: 10/25/2022]
Abstract
The spontaneous incidence of chloramphenicol (Cam) resistant mutant bacteria is at least ten-fold higher in cultures of enterohemorrhagic Escherichia coli O157:H7 strain EDL933 than in E. coli K-12. It is at least 100-fold higher in the dam (DNA adenine methyltransferase) derivative of EDL933, compared to the dam strain of E. coli K-12, thereby preventing the use of Cam resistance as a marker in gene replacement technology. Genome sequencing of Cam-resistant isolates of EDL933 and its dam derivatives showed that the marR (multiple antibiotic resistance) gene was mutated in every case but not in the Cam-sensitive parental strains. As expected from mutation in the marR gene, the Cam-resistant bacteria were also found to be resistant to tetracycline and nalidixic acid. The marR gene in strain EDL933 is annotated as a shorter open reading frame than that in E. coli K-12 but the longer marR(+) open reading frame was more efficient at complementing the marR antibiotic-resistance phenotype of strain EDL933. Beta-lactamase-tolerant derivatives were present at frequencies 10-100 times greater in cultures of marR derivatives of strain EDL933 than the parent strain. Spontaneous mutation frequency to rifampicin, spectinomycin and streptomycin resistance was the same in E. coli O157:H7 and E. coli K-12 strains.
Collapse
Affiliation(s)
- Benjamin R Carone
- Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, United States
| | - Tao Xu
- Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, United States
| | - Kenan C Murphy
- Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA 01605, United States
| | - Martin G Marinus
- Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, United States.
| |
Collapse
|
28
|
Contribution of phenotypic heterogeneity to adaptive antibiotic resistance. Proc Natl Acad Sci U S A 2013; 111:355-60. [PMID: 24351930 DOI: 10.1073/pnas.1316084111] [Citation(s) in RCA: 137] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Antibiotic-resistant isolates of Salmonella enterica were selected on plates containing lethal concentrations of rifampicin, kanamycin, and nalidixic acid. The stability of the resistance phenotype was scored after nonselective growth. Rifampicin-resistant (Rif(r)) isolates were stable, suggesting that they had arisen by mutation. Mutations in the rpoB gene were detected indeed in Rif(r) mutants. In contrast, a fraction of kanamycin-resistant (Km(r)) and nalidixic acid-resistant (Nal(r)) isolates showed reduced resistance after nonselective growth, suggesting that mechanisms other than mutation had contributed to bacterial survival upon lethal selection. Single-cell analysis revealed heterogeneity in expression of the porin gene ompC, and subpopulation separation provided evidence that reduced ompC expression confers adaptive resistance to kanamycin. In the case of Nal(r) isolates, mutations in the gyrA gene were present in most nalidixic acid-resistant isolates. However, the efflux pump inhibitor Phe-Arg-β-naphtylamide (PAβN) reduced the level of resistance in Nal(r) mutants, indicating that active efflux contributes to the overall level of nalidixic acid resistance. Heterogeneous efflux pump activity was detected in single cells and colonies, and a correlation between high efflux and increased resistance to nalidixic acid was found. These observations suggest that fluctuations in the expression and the activity of critical functions of the bacterial cell, alone or combined with mutations, can contribute to adaptive resistance to antibiotics.
Collapse
|
29
|
Adaptive and mutational resistance: role of porins and efflux pumps in drug resistance. Clin Microbiol Rev 2013; 25:661-81. [PMID: 23034325 DOI: 10.1128/cmr.00043-12] [Citation(s) in RCA: 540] [Impact Index Per Article: 49.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The substantial use of antibiotics in the clinic, combined with a dearth of new antibiotic classes, has led to a gradual increase in the resistance of bacterial pathogens to these compounds. Among the various mechanisms by which bacteria endure the action of antibiotics, those affecting influx and efflux are of particular importance, as they limit the interaction of the drug with its intracellular targets and, consequently, its deleterious effects on the cell. This review evaluates the impact of porins and efflux pumps on two major types of resistance, namely, mutational and adaptive types of resistance, both of which are regarded as key phenomena in the global rise of antibiotic resistance among pathogenic microorganisms. In particular, we explain how adaptive and mutational events can dramatically influence the outcome of antibiotic therapy by altering the mechanisms of influx and efflux of antibiotics. The identification of porins and pumps as major resistance markers has opened new possibilities for the development of novel therapeutic strategies directed specifically against these mechanisms.
Collapse
|
30
|
Lavigne JP, Sotto A, Nicolas-Chanoine MH, Bouziges N, Pagès JM, Davin-Regli A. An adaptive response of Enterobacter aerogenes to imipenem: regulation of porin balance in clinical isolates. Int J Antimicrob Agents 2012; 41:130-6. [PMID: 23280442 DOI: 10.1016/j.ijantimicag.2012.10.010] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Revised: 10/21/2012] [Accepted: 10/24/2012] [Indexed: 12/28/2022]
Abstract
Imipenem (IPM) is a carbapenem antibiotic frequently used in severe hospital infections. Several reports have mentioned the emergence of resistant isolates exhibiting membrane modifications. A study was conducted between September 2005 and August 2007 to survey infections due to Enterobacter aerogenes in patients hospitalised in a French university hospital. Resistant E. aerogenes clinical isolates obtained from patients treated with IPM and collected during the 3 months following initiation of treatment were phenotypically and molecularly characterised for β-lactamases, efflux pumps activity and outer membrane proteins. Among the 339 patients infected with E. aerogenes during the study period, 41 isolates (12.1%) were resistant to extended-spectrum cephalosporins and 17 patients (5.0%) were treated with IPM. The isolates from these 17 patients presented TEM-24 and basal efflux expression. Following IPM treatment, an IPM-intermediate-susceptible (IPM-I) isolate emerged in 11 patients and an IPM-resistant (IPM-R) isolate in 6 patients. A change in the porin balance (Omp35/Omp36) was observed in IPM-I isolates exhibiting ertapenem resistance. Finally, a porin deficiency (Omp35 and Omp36 absence) was detected in IPM-R isolates associated with efflux pump expression. This study indicates that the alteration in porin expression, including the shift of porin expression and lack of porins, contribute to the E. aerogenes adaptive response to IPM treatment.
Collapse
Affiliation(s)
- Jean-Philippe Lavigne
- UMR-MD1, Aix-Marseille Université, IRBA, Facultés de Médecine et de Pharmacie, Marseille, France
| | | | | | | | | | | |
Collapse
|
31
|
Snoussi S, May AE, Coquet L, Chan P, Jouenne T, Landoulsi A, Dé E. Adaptation of Salmonella enterica Hadar under static magnetic field: effects on outer membrane protein pattern. Proteome Sci 2012; 10:6. [PMID: 22304719 PMCID: PMC3292939 DOI: 10.1186/1477-5956-10-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2011] [Accepted: 02/03/2012] [Indexed: 12/29/2022] Open
Abstract
Background Salmonella enterica serovar Hadar (S. Hadar) is a highly prevalent foodborne pathogen and therefore a major cause of human gastroenteritis worldwide. Outer membrane proteins whose production is often regulated by environmental conditions also play important roles in the adaptability of bacterial pathogens to various environments. Results The present study investigated the adaptation of S. Hadar under the effect of acute static magnetic field exposure (200 mT, 9 h) and the impact on the outer membrane protein pattern. Via two-dimensional electrophoresis (2-DE) and LC-MS/MS spectrometry, we compared the proteome of enriched-outer membrane fraction before and after exposure to a magnetic field. A total of 11 proteins, displaying more than a two-fold change, were differentially expressed in exposed cells, among which 7 were up-regulated and 4 down-regulated. These proteins were involved in the integrity of cell envelope (TolB, Pal), in the response to oxidative stress (OmpW, dihydrolipoamide dehydrogenase, UspF), in the oxidative stress status (bacterioferritin), in virulence (OmpX, Yfgl) or in motility (FlgE and UspF). Complementary experiments associated the down-regulation of FlgE and UspF with an alteration of swarming, a flagella-driven motility, under SMF. Furthermore, the antibiotic disc diffusion method confirmed a decrease of gentamicin susceptibility in exposed cells. This decrease could be partly associated with the up-regulation of TolC, outer membrane component of an efflux pump. OmpA, a multifunctional protein, was up-regulated. Conclusions SMF (200 mT) seems to maintain the cell envelope integrity and to submit the exposed cells to an oxidative stress. Some alterations suggest an increase of the ability of exposed cells to form biofilms.
Collapse
Affiliation(s)
- Sarra Snoussi
- Laboratoire de Biochimie et Biologie Moléculaire, Faculté des Sciences de Bizerte, Université de Carthage, Zarzouna, Bizerte, Tunisie.
| | | | | | | | | | | | | |
Collapse
|
32
|
Gao H, Zhang Y, Tan Y, Wang L, Xiao X, Guo Z, Zhou D, Yang R. Transcriptional regulation of ompF2, an ompF paralogue, in Yersinia pestis. Can J Microbiol 2011; 57:468-75. [PMID: 21627465 DOI: 10.1139/w11-028] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A regulatory circuit composed of three porins (OmpF, OmpC, and OmpX) and two transcriptional regulators (OmpR and CRP) has previously been characterized in Yersinia pestis . In this follow-up study, OmpF2, an OmpF paralogue, was integrated into this regulatory circuit. Only basal expression was detected for ompF2 in the wild-type strain under different osmotic conditions. The ompF2 transcription was dramatically enhanced with increasing medium osmolarity in the ompR null mutant background. The CRP regulator had no regulatory effect on ompF2 under the growth conditions tested.
Collapse
Affiliation(s)
- He Gao
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, People's Republic of China
| | | | | | | | | | | | | | | |
Collapse
|
33
|
Phenotypic and transcriptional analysis of the osmotic regulator OmpR in Yersinia pestis. BMC Microbiol 2011; 11:39. [PMID: 21345178 PMCID: PMC3050692 DOI: 10.1186/1471-2180-11-39] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2010] [Accepted: 02/23/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The osmotic regulator OmpR in Escherichia coli regulates differentially the expression of major porin proteins OmpF and OmpC. In Yersinia enterocolitica and Y. pseudotuberculosis, OmpR is required for both virulence and survival within macrophages. However, the phenotypic and regulatory roles of OmpR in Y. pestis are not yet fully understood. RESULTS Y. pestis OmpR is involved in building resistance against phagocytosis and controls the adaptation to various stressful conditions met in macrophages. The ompR mutation likely did not affect the virulence of Y. pestis strain 201 that was a human-avirulent enzootic strain. The microarray-based comparative transcriptome analysis disclosed a set of 224 genes whose expressions were affected by the ompR mutation, indicating the global regulatory role of OmpR in Y. pestis. Real-time RT-PCR or lacZ fusion reporter assay further validated 16 OmpR-dependent genes, for which OmpR consensus-like sequences were found within their upstream DNA regions. ompC, F, X, and R were up-regulated dramatically with the increase of medium osmolarity, which was mediated by OmpR occupying the target promoter regions in a tandem manner. CONCLUSION OmpR contributes to the resistance against phagocytosis or survival within macrophages, which is conserved in the pathogenic yersiniae. Y. pestis OmpR regulates ompC, F, X, and R directly through OmpR-promoter DNA association. There is an inducible expressions of the pore-forming proteins OmpF, C, and × at high osmolarity in Y. pestis, in contrast to the reciprocal regulation of them in E. coli. The main difference is that ompF expression is not repressed at high osmolarity in Y. pestis, which is likely due to the absence of a promoter-distal OmpR-binding site for ompF.
Collapse
|
34
|
Gao H, Zhang Y, Yang L, Liu X, Guo Z, Tan Y, Han Y, Huang X, Zhou D, Yang R. Regulatory effects of cAMP receptor protein (CRP) on porin genes and its own gene in Yersinia pestis. BMC Microbiol 2011; 11:40. [PMID: 21345179 PMCID: PMC3050693 DOI: 10.1186/1471-2180-11-40] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2010] [Accepted: 02/23/2011] [Indexed: 11/10/2022] Open
Abstract
Background The cAMP receptor protein (CRP) is a global bacterial regulator that controls many target genes. The CRP-cAMP complex regulates the ompR-envZ operon in E. coli directly, involving both positive and negative regulations of multiple target promoters; further, it controls the production of porins indirectly through its direct action on ompR-envZ. Auto-regulation of CRP has also been established in E. coli. However, the regulation of porin genes and its own gene by CRP remains unclear in Y. pestis. Results Y. pestis employs a distinct mechanism indicating that CRP has no regulatory effect on the ompR-envZ operon; however, it stimulates ompC and ompF directly, while repressing ompX. No transcriptional regulatory association between CRP and its own gene can be detected in Y. pestis, which is also in contrast to the fact that CRP acts as both repressor and activator for its own gene in E. coli. It is likely that Y. pestis OmpR and CRP respectively sense different signals (medium osmolarity, and cellular cAMP levels) to regulate porin genes independently. Conclusion Although the CRP of Y. pestis shows a very high homology to that of E. coli, and the consensus DNA sequence recognized by CRP is shared by the two bacteria, the Y. pestis CRP can recognize the promoters of ompC, F, and X directly rather than that of its own gene, which is different from the relevant regulatory circuit of E. coli. Data presented here indicate a remarkable remodeling of the CRP-mediated regulation of porin genes and of its own one between these two bacteria.
Collapse
Affiliation(s)
- He Gao
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, PR China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Outer membrane protein X (Ail) contributes to Yersinia pestis virulence in pneumonic plague and its activity is dependent on the lipopolysaccharide core length. Infect Immun 2010; 78:5233-43. [PMID: 20837715 DOI: 10.1128/iai.00783-10] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Yersinia pestis, the causative agent of plague, is one of the most virulent microorganisms known. The outer membrane protein X (OmpX) in Y. pestis KIM is required for efficient bacterial adherence to and internalization by cultured HEp-2 cells and confers resistance to human serum. Here, we tested the contribution of OmpX to disease progression in the fully virulent Y. pestis CO92 strain by engineering a deletion mutant and comparing its ability in mediating pneumonic plague to that of the wild type in two animal models. The deletion of OmpX delayed the time to death up to 48 h in a mouse model and completely attenuated virulence in a rat model of disease. All rats challenged with 1 × 10(8) CFU of the ompX mutant survived, compared to the 50% lethal dose (LD50) of 1.2 × 10(3) CFU for the wild-type strain. Because murine serum is not bactericidal for the ompX mutant, the mechanism underlying the delay in time to death in mice was attributed to loss of adhesion/internalization properties but not serum resistance. The rat model, which is most similar to humans, highlighted the critical role of serum resistance in disease. To resolve conflicting evidence for the role of Y. pestis lipopolysaccharide (LPS) and OmpX in serum resistance, ompX was cloned into Escherichia coli D21 and three isogenic derivatives engineered to have progressively truncated LPS core saccharides. OmpX-mediated serum resistance, adhesiveness, and invasiveness, although dependent on LPS core length, displayed these functions in E. coli, independently of other Yersinia proteins and/or LPS. Also, autoaggregation was required for efficient OmpX-mediated adhesiveness and internalization but not serum resistance.
Collapse
|
36
|
Coldham NG, Webber M, Woodward MJ, Piddock LJV. A 96-well plate fluorescence assay for assessment of cellular permeability and active efflux in Salmonella enterica serovar Typhimurium and Escherichia coli. J Antimicrob Chemother 2010; 65:1655-63. [DOI: 10.1093/jac/dkq169] [Citation(s) in RCA: 117] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
37
|
Catoire LJ, Zoonens M, van Heijenoort C, Giusti F, Guittet E, Popot JL. Solution NMR mapping of water-accessible residues in the transmembrane beta-barrel of OmpX. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2009; 39:623-30. [PMID: 19639312 DOI: 10.1007/s00249-009-0513-2] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2009] [Revised: 06/19/2009] [Accepted: 06/22/2009] [Indexed: 12/11/2022]
Abstract
The atomic structure of OmpX, the smallest member of the bacterial outer membrane protein family, has been previously established by X-ray crystallography and NMR spectroscopy. In apparent conflict with electrophysiological studies, the lumen of its transmembrane beta-barrel appears too tightly packed with amino acid side chains to let any solute flow through. In the present study, high-resolution solution NMR spectra were obtained of OmpX kept water-soluble by either amphipol A8-35 or the detergent dihexanoylphosphatidylcholine. Hydrogen/deuterium exchange measurements performed after prolonged equilibration show that, whatever the surfactant used, some of the amide protons of the membrane-spanning region exchange much more readily than others, which likely reflects the dynamics of the barrel.
Collapse
Affiliation(s)
- Laurent J Catoire
- Laboratoire de Physico-Chimie Moléculaire des Protéines Membranaires, UMR 7099, CNRS/Université Paris-7, Institut de Biologie Physico-Chimique (FRC 550), 75005 Paris, France.
| | | | | | | | | | | |
Collapse
|
38
|
Chen YG, Zhang Y, Yu YS, Qu TT, Wei ZQ, Shen P, Li LJ. In vivo development of carbapenem resistance in clinical isolates of Enterobacter aerogenes producing multiple β-lactamases. Int J Antimicrob Agents 2008; 32:302-7. [DOI: 10.1016/j.ijantimicag.2008.02.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2008] [Revised: 02/20/2008] [Accepted: 02/21/2008] [Indexed: 10/21/2022]
|
39
|
Papenfort K, Pfeiffer V, Lucchini S, Sonawane A, Hinton JCD, Vogel J. Systematic deletion of Salmonella small RNA genes identifies CyaR, a conserved CRP-dependent riboregulator of OmpX synthesis. Mol Microbiol 2008; 68:890-906. [DOI: 10.1111/j.1365-2958.2008.06189.x] [Citation(s) in RCA: 131] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
40
|
Kolodziejek AM, Sinclair DJ, Seo KS, Schnider DR, Deobald CF, Rohde HN, Viall AK, Minnich SS, Hovde CJ, Minnich SA, Bohach GA. Phenotypic characterization of OmpX, an Ail homologue of Yersinia pestis KIM. MICROBIOLOGY-SGM 2007; 153:2941-2951. [PMID: 17768237 DOI: 10.1099/mic.0.2006/005694-0] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The goal of this study was to characterize the Yersinia pestis KIM OmpX protein. Yersinia spp. provide a model for studying several virulence processes including attachment to, and internalization by, host cells. For Yersinia enterocolitica and Yersinia pseudotuberculosis, Ail, YadA and Inv, have been implicated in these processes. In Y. pestis, YadA and Inv are inactivated. Genomic analysis of two Y. pestis strains revealed four loci with sequence homology to Ail. One of these genes, designated y1324 in the Y. pestis KIM database, encodes a protein designated OmpX. The mature protein has a predicted molecular mass of 17.47 kDa, shares approximately 70 % sequence identity with Y. enterocolitica Ail, and has an identical homologue, designated Ail, in the Y. pestis CO92 database. The present study compared the Y. pestis KIM6(+) parental strain with a mutant derivative having an engineered disruption of the OmpX structural gene. The parental strain (and a merodiploid control strain) expressed OmpX at 28 and 37 degrees C, and the protein was detectable throughout all phases of growth. OmpX was required for efficient adherence to, and internalization by, cultured HEp-2 cell monolayers and conferred resistance to the bactericidal effect of human serum. Deletion of ompX resulted in a significantly reduced autoaggregation phenotype and loss of pellicle formation in vitro. These results suggest that Y. pestis OmpX shares functional homology with Y. enterocolitica Ail in adherence, internalization into epithelial cells and serum resistance.
Collapse
Affiliation(s)
- Anna M Kolodziejek
- Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA
| | - Dylan J Sinclair
- Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA
| | - Keun S Seo
- Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA
| | - Darren R Schnider
- Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA
| | - Claudia F Deobald
- Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA
| | - Harold N Rohde
- Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA
| | - Austin K Viall
- Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA
| | - Scott S Minnich
- Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA
| | - Carolyn J Hovde
- Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA
| | - Scott A Minnich
- Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA
| | - Gregory A Bohach
- Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA
| |
Collapse
|
41
|
Dupont M, James CE, Chevalier J, Pagès JM. An early response to environmental stress involves regulation of OmpX and OmpF, two enterobacterial outer membrane pore-forming proteins. Antimicrob Agents Chemother 2007; 51:3190-8. [PMID: 17606680 PMCID: PMC2043185 DOI: 10.1128/aac.01481-06] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacterial adaptation to external stresses and toxic compounds is a key step in the emergence of multidrug-resistant strains that are a serious threat to human health. Although some of the proteins and regulators involved in antibiotic resistance mechanisms have been described, no information is available to date concerning the early bacterial response to external stresses. Here we report that the expression of ompX, encoding an outer membrane protein, is increased during early exposure to drugs or environmental stresses. At the same time, the level of ompF porin expression is noticeably affected. Because of the role of these proteins in membrane permeability, these data suggest that OmpF and OmpX are involved in the control of the penetration of antibiotics such as beta-lactams and fluoroquinolones through the enterobacterial outer membrane. Consequently, the early control of ompX and ompF induced by external stresses may represent a preliminary response to antibiotics, thus triggering the initial bacterial line of defense against antibiotherapy.
Collapse
Affiliation(s)
- Myrielle Dupont
- UMR-MD1, Faculté de Médecine, 27 Blvd. Jean Moulin, 13385 Marseille Cedex 05, France
| | | | | | | |
Collapse
|
42
|
Cox K, Bond PJ, Grottesi A, Baaden M, Sansom MSP. Outer membrane proteins: comparing X-ray and NMR structures by MD simulations in lipid bilayers. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2007; 37:131-41. [PMID: 17551722 DOI: 10.1007/s00249-007-0185-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2006] [Revised: 05/07/2007] [Accepted: 05/08/2007] [Indexed: 11/26/2022]
Abstract
The structures of three bacterial outer membrane proteins (OmpA, OmpX and PagP) have been determined by both X-ray diffraction and NMR. We have used multiple (7 x 15 ns) MD simulations to compare the conformational dynamics resulting from the X-ray versus the NMR structures, each protein being simulated in a lipid (DMPC) bilayer. Conformational drift was assessed via calculation of the root mean square deviation as a function of time. On this basis the 'quality' of the starting structure seems mainly to influence the simulation stability of the transmembrane beta-barrel domain. Root mean square fluctuations were used to compare simulation mobility as a function of residue number. The resultant residue mobility profiles were qualitatively similar for the corresponding X-ray and NMR structure-based simulations. However, all three proteins were generally more mobile in the NMR-based than in the X-ray simulations. Principal components analysis was used to identify the dominant motions within each simulation. The first two eigenvectors (which account for >50% of the protein motion) reveal that such motions are concentrated in the extracellular loops and, in the case of PagP, in the N-terminal alpha-helix. Residue profiles of the magnitude of motions corresponding to the first two eigenvectors are similar for the corresponding X-ray and NMR simulations, but the directions of these motions correlate poorly reflecting incomplete sampling on a approximately 10 ns timescale.
Collapse
Affiliation(s)
- Katherine Cox
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | | | | | | | | |
Collapse
|
43
|
Viveiros M, Dupont M, Rodrigues L, Couto I, Davin-Regli A, Martins M, Pagès JM, Amaral L. Antibiotic stress, genetic response and altered permeability of E. coli. PLoS One 2007; 2:e365. [PMID: 17426813 PMCID: PMC1838523 DOI: 10.1371/journal.pone.0000365] [Citation(s) in RCA: 154] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2007] [Accepted: 03/08/2007] [Indexed: 12/05/2022] Open
Abstract
Background Membrane permeability is the first step involved in resistance of bacteria to an antibiotic. The number and activity of efflux pumps and outer membrane proteins that constitute porins play major roles in the definition of intrinsic resistance in Gram-negative bacteria that is altered under antibiotic exposure. Methodology/Principal Findings Here we describe the genetic regulation of porins and efflux pumps of Escherichia coli during prolonged exposure to increasing concentrations of tetracycline and demonstrate, with the aid of quantitative real-time reverse transcriptase-polymerase chain reaction methodology and western blot detection, the sequence order of genetic expression of regulatory genes, their relationship to each other, and the ensuing increased activity of genes that code for transporter proteins of efflux pumps and down-regulation of porin expression. Conclusions/Significance This study demonstrates that, in addition to the transcriptional regulation of genes coding for membrane proteins, the post-translational regulation of proteins involved in the permeability of Gram-negative bacteria also plays a major role in the physiological adaptation to antibiotic exposure. A model is presented that summarizes events during the physiological adaptation of E. coli to tetracycline exposure.
Collapse
Affiliation(s)
- Miguel Viveiros
- Unit of Mycobacteriology, Unidade de Parasitologia e Microbiologia Médicas (UPMM), Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Myrielle Dupont
- UMR-MD-1, IFR48, Facultés de Médecine et de Pharmacie, Université de la Méditerranée, Marseille, France
| | - Liliana Rodrigues
- Unit of Mycobacteriology, Unidade de Parasitologia e Microbiologia Médicas (UPMM), Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Isabel Couto
- Unit of Mycobacteriology, Unidade de Parasitologia e Microbiologia Médicas (UPMM), Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Lisboa, Portugal
- Centro de Recursos Microbiológicos (CREM), Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Anne Davin-Regli
- UMR-MD-1, IFR48, Facultés de Médecine et de Pharmacie, Université de la Méditerranée, Marseille, France
| | - Marta Martins
- Unit of Mycobacteriology, Unidade de Parasitologia e Microbiologia Médicas (UPMM), Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Jean-Marie Pagès
- UMR-MD-1, IFR48, Facultés de Médecine et de Pharmacie, Université de la Méditerranée, Marseille, France
| | - Leonard Amaral
- Unit of Mycobacteriology, Unidade de Parasitologia e Microbiologia Médicas (UPMM), Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Lisboa, Portugal
- * To whom correspondence should be addressed. E-mail:
| |
Collapse
|
44
|
Arnold T, Poynor M, Nussberger S, Lupas AN, Linke D. Gene duplication of the eight-stranded beta-barrel OmpX produces a functional pore: a scenario for the evolution of transmembrane beta-barrels. J Mol Biol 2006; 366:1174-84. [PMID: 17217961 DOI: 10.1016/j.jmb.2006.12.029] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2006] [Revised: 12/12/2006] [Accepted: 12/12/2006] [Indexed: 11/23/2022]
Abstract
The repeating unit of outer membrane beta-barrels from Gram-negative bacteria is the beta-hairpin, and representatives of this protein family always have an even strand number between eight and 22. Two dominant structural forms have eight and 16 strands, respectively, suggesting gene duplication as a possible mechanism for their evolution. We duplicated the sequence of OmpX, an eight-stranded beta-barrel protein of known structure, and obtained a beta-barrel, designated Omp2X, which can fold in vitro and in vivo. Using single-channel conductance measurements and PEG exclusion assays, we found that Omp2X has a pore size similar to that of OmpC, a natural 16-stranded barrel. Fusions of the homologous proteins OmpX, OmpA and OmpW were able to fold in vitro in all combinations tested, revealing that the general propensity to form a beta-barrel is sufficient to evolve larger barrels by simple genetic events.
Collapse
Affiliation(s)
- Thomas Arnold
- Max Planck Institute for Developmental Biology, Department Protein Evolution, Spemannstr. 35, 72076 Tübingen, Germany
| | | | | | | | | |
Collapse
|
45
|
Thiolas A, Bollet C, La Scola B, Raoult D, Pagès JM. Successive emergence of Enterobacter aerogenes strains resistant to imipenem and colistin in a patient. Antimicrob Agents Chemother 2005; 49:1354-8. [PMID: 15793111 PMCID: PMC1068582 DOI: 10.1128/aac.49.4.1354-1358.2005] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Enterobacter aerogenes is an agent of hospital-acquired infection that exhibits a remarkable resistance to beta-lactam antibiotics during therapy. Five successive isolates of E. aerogenes infecting a patient and exhibiting a multiresistance phenotype to beta-lactam antibiotics and fluoroquinolones were investigated. Among these clinical strains, four presented resistant phenotypes during successive imipenem and colistin treatments. The involved resistance mechanisms exhibited by the successive isolates were associated with alterations of the outer membrane that caused a porin decrease and lipopolysaccharide modifications.
Collapse
Affiliation(s)
- Aurélie Thiolas
- Enveloppe Bactérienne, Perméabilité et Antibiotiques, EA2197, IFR48, Faculté de Médecine, 27 Blvd. Jean Moulin, 13385 Marseille Cedex 05, France
| | | | | | | | | |
Collapse
|