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Irusan D, Akshay SD, Shetty VP, Karunasagar I, Deekshit VK, Rohit A. Analysis of mcr family of colistin resistance genes in Gram-negative isolates from a tertiary care hospital in India. J Appl Microbiol 2024; 135:lxae172. [PMID: 38986507 DOI: 10.1093/jambio/lxae172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Revised: 06/25/2024] [Accepted: 07/09/2024] [Indexed: 07/12/2024]
Abstract
AIM Colistin serves as the drug of last resort for combating numerous multidrug-resistant (MDR) Gram-negative infections. Its efficacy is hampered by the prevalent issue of colistin resistance, which severely limits treatment options for critically ill patients. Identifying resistance genes is crucial for controlling resistance spread, with horizontal gene transfer being the primary mechanism among bacteria. This study aimed to assess the prevalence of plasmid-mediated mcr genes associated with colistin resistance in Gram-negative bacteria, utilizing both genotypic and phenotypic tests. METHODS AND RESULTS The clinical isolates (n = 913) were obtained from a tertiary care center in Chennai, India. Colistin resistance was seen among Gram-negative isolates. These strains underwent screening for mcr-1, mcr-3, mcr-4, and mcr-5 genes via conventional PCR. Additionally, mcr-positive isolates were confirmed through Sanger sequencing and phenotypic testing. The bacterial isolates predominantly comprised Klebsiella pneumoniae (62.43%), Escherichia coli (19.71%), Pseudomonas aeruginosa (10.73%), and Acinetobacter baumannii (4.81%), along with other species. All isolates exhibited multidrug resistance to three or more antibiotic classes. Colistin resistance, determined via broth microdilution (BMD) using CLSI guidelines, was observed in 13.08% of the isolates studied. Notably, mcr-5 was detected in K. pneumoniae in PCR, despite its absence in Sanger sequencing and phenotypic tests (including the combined-disk test, colistin MIC in the presence of EDTA, and Zeta potential assays). This finding underscores the importance of employing multiple diagnostic approaches to accurately identify colistin resistance mechanisms.
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Affiliation(s)
- Dhinakaran Irusan
- Department of Microbiology, The Madras Medical Mission, 4-A, Mogappair, Chennai, Tamil Nadu 600037, India
| | - Sadanand Dangari Akshay
- Department of Bio & Nano Technology, Nitte (Deemed to be University), Nitte University Centre for Science Education and Research, Paneer Campus, Deralakatte, Mangaluru 575018, India
| | - Varsha Prakash Shetty
- Department of Infectious Diseases & Microbial Genomics, Nitte (Deemed to be University), Nitte University Centre for Science Education and Research, Paneer Campus, Deralakatte, Mangaluru 575018, India
| | - Iddya Karunasagar
- Nitte (Deemed to be University), Medical Sciences Complex, Mangaluru 575018, India
| | - Vijaya Kumar Deekshit
- Department of Infectious Diseases & Microbial Genomics, Nitte (Deemed to be University), Nitte University Centre for Science Education and Research, Paneer Campus, Deralakatte, Mangaluru 575018, India
| | - Anusha Rohit
- Department of Microbiology, The Madras Medical Mission, 4-A, Mogappair, Chennai, Tamil Nadu 600037, India
- Nitte (Deemed to be University), Medical Sciences Complex, Mangaluru 575018, India
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Nayak S, Akshay SD, Deekshit VK, Raj JM, Maiti B. Exposure to imipenem at sub-minimum inhibitory concentration leads to altered expression of major outer membrane proteins in Acinetobacter baumannii. J Appl Microbiol 2024; 135:lxae105. [PMID: 38653725 DOI: 10.1093/jambio/lxae105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 04/15/2024] [Accepted: 04/22/2024] [Indexed: 04/25/2024]
Abstract
AIMS Acinetobacter baumannii is a nosocomial pathogen known to be multidrug-resistant (MDR), especially to drugs of the carbapenem class. Several factors contribute to resistance, including efflux pumps, β-lactamases, alteration of target sites, and permeability defects. In addition, outer membrane proteins (OMPs), like porins are involved in the passage of antibiotics, and their alteration could lead to resistance development. This study aimed to explore the possible involvement of porins and OMPs in developing carbapenem resistance due to differential expression. METHODS AND RESULTS The antibiotic-susceptible and MDR isolates of A. baumannii were first studied for differences in their transcriptional levels of OMP expression and OMP profiles. The antibiotic-susceptible isolates were further treated with imipenem, and it was found that the omp genes were differentially expressed. Six of the nine genes studied were upregulated at 1 h of exposure to imipenem. Their expression gradually decreased with time, further confirmed by their OMP profile and two-dimensional gel electrophoresis. CONCLUSIONS This study could identify OMPs that were differentially expressed on exposure to imipenem. Hence, this study provides insights into the role of specific OMPs in antibiotic resistance in A. baumannii.
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Affiliation(s)
- Srajana Nayak
- Nitte (Deemed to be University), Nitte University Centre for Science Education and Research, Department of Bio & Nano Technology, Deralakatte, Mangaluru 575018, India
| | - Sadanand Dangari Akshay
- Nitte (Deemed to be University), Nitte University Centre for Science Education and Research, Department of Bio & Nano Technology, Deralakatte, Mangaluru 575018, India
| | - Vijaya Kumar Deekshit
- Nitte (Deemed to be University), Nitte University Centre for Science Education and Research, Department of Infectious Diseases & Microbial Genomics, Deralakatte, Mangaluru 575018, India
| | - Juliet Mohan Raj
- Nitte (Deemed to be University), Nitte University Centre for Science Education and Research, Department of Infectious Diseases & Microbial Genomics, Deralakatte, Mangaluru 575018, India
| | - Biswajit Maiti
- Nitte (Deemed to be University), Nitte University Centre for Science Education and Research, Department of Bio & Nano Technology, Deralakatte, Mangaluru 575018, India
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Chowdhury AR, Mukherjee D, Chatterjee R, Chakravortty D. Defying the odds: Determinants of the antimicrobial response of Salmonella Typhi and their interplay. Mol Microbiol 2024; 121:213-229. [PMID: 38071466 DOI: 10.1111/mmi.15209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 11/12/2023] [Accepted: 11/27/2023] [Indexed: 02/12/2024]
Abstract
Salmonella Typhi, the invasive serovar of S. enterica subspecies enterica, causes typhoid fever in healthy human hosts. The emergence of antibiotic-resistant strains has consistently challenged the successful treatment of typhoid fever with conventional antibiotics. Antimicrobial resistance (AMR) in Salmonella is acquired either by mutations in the genomic DNA or by acquiring extrachromosomal DNA via horizontal gene transfer. In addition, Salmonella can form a subpopulation of antibiotic persistent (AP) cells that can survive at high concentrations of antibiotics. These have reduced the effectiveness of the first and second lines of antibiotics used to treat Salmonella infection. The recurrent and chronic carriage of S. Typhi in human hosts further complicates the treatment process, as a remarkable shift in the immune response from pro-inflammatory Th1 to anti-inflammatory Th2 is observed. Recent studies have also highlighted the overlap between AP, persistent infection (PI) and AMR. These incidents have revealed several areas of research. In this review, we have put forward a timeline for the evolution of antibiotic resistance in Salmonella and discussed the different mechanisms of the same availed by the pathogen at the genotypic and phenotypic levels. Further, we have presented a detailed discussion on Salmonella antibiotic persistence (AP), PI, the host and bacterial virulence factors that can influence PI, and how both AP and PI can lead to AMR.
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Affiliation(s)
- Atish Roy Chowdhury
- Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, India
| | - Debapriya Mukherjee
- Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, India
| | - Ritika Chatterjee
- Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, India
| | - Dipshikha Chakravortty
- Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, India
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, India
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Yuan L, Fan L, Dai H, He G, Zheng X, Rao S, Yang Z, Jiao XA. Multi-omics reveals the increased biofilm formation of Salmonella Typhimurium M3 by the induction of tetracycline at sub-inhibitory concentrations. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 899:165695. [PMID: 37487904 DOI: 10.1016/j.scitotenv.2023.165695] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 07/17/2023] [Accepted: 07/19/2023] [Indexed: 07/26/2023]
Abstract
Exposure to sub-inhibitory concentrations (sub-MICs) of antibiotics could induce the biofilm formation of microorganisms, but its underlying mechanisms still remain elusive. In the present work, biofilm formation by Salmonella Typhimurium M3 was increased when in the presence of tetracycline at sub-MIC, and the highest induction was observed with tetracycline at 1/8 MIC. The integration of RNA-sequencing and untargeted metabolomics was applied in order to further decipher the potential mechanisms for this observation. In total, 439 genes and 144 metabolites of S. Typhimurium M3 were significantly expressed after its exposure to 1/8 MIC of tetracycline. In addition, the co-expression analysis revealed that 6 genes and 8 metabolites play a key role in response to 1/8 MIC of tetracycline. The differential genes and metabolites were represented in 12 KEGG pathways, including five pathways of amino acid metabolism (beta-alanine metabolism, tryptophan metabolism, arginine and proline metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, and glutathione metabolism), three lipid metabolism pathways (biosynthesis of unsaturated fatty acids, fatty acid degradation, and fatty acid biosynthesis), two nucleotide metabolism pathways (purine metabolism, and pyrimidine metabolism), pantothenate and CoA biosynthesis, and ABC transporters. Metabolites (anthranilate, indole, and putrescine) from amino acid metabolism may act as signaling molecules to promote the biofilm formation of S. Typhimurium M3. The results of this work highlight the importance of low antimicrobial concentrations on foodborne pathogens of environmental origin.
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Affiliation(s)
- Lei Yuan
- School of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu 225127, China; Jiangsu Key Laboratory of Zoonoses, Yangzhou, Jiangsu 225009, China
| | - Luyao Fan
- School of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu 225127, China
| | - Hongchao Dai
- School of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu 225127, China
| | - Guoqing He
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Xiangfeng Zheng
- School of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu 225127, China
| | - Shengqi Rao
- School of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu 225127, China
| | - Zhenquan Yang
- School of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu 225127, China.
| | - Xin-An Jiao
- Jiangsu Key Laboratory of Zoonoses, Yangzhou, Jiangsu 225009, China.
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Akshay SD, Deekshit VK, Mohan Raj J, Maiti B. Outer Membrane Proteins and Efflux Pumps Mediated Multi-Drug Resistance in Salmonella: Rising Threat to Antimicrobial Therapy. ACS Infect Dis 2023; 9:2072-2092. [PMID: 37910638 DOI: 10.1021/acsinfecdis.3c00408] [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] [Indexed: 11/03/2023]
Abstract
Despite colossal achievements in antibiotic therapy in recent decades, drug-resistant pathogens have remained a leading cause of death and economic loss globally. One such WHO-critical group pathogen is Salmonella. The extensive and inappropriate treatments for Salmonella infections have led from multi-drug resistance (MDR) to extensive drug resistance (XDR). The synergy between efflux-mediated systems and outer membrane proteins (OMPs) may favor MDR in Salmonella. Differential expression of the efflux system and OMPs (influx) and positional mutations are the factors that can be correlated to the development of drug resistance. Insights into the mechanism of influx and efflux of antibiotics can aid in developing a structurally stable molecule that can be proficient at escaping from the resistance loops in Salmonella. Understanding the strategic responsibilities and developing policies to address the surge of drug resistance at the national, regional, and global levels are the needs of the hour. In this Review, we attempt to aggregate all the available research findings and delineate the resistance mechanisms by dissecting the involvement of OMPs and efflux systems. Integrating major OMPs and the efflux system's differential expression and positional mutation in Salmonella may provide insight into developing strategic therapies for one health application.
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Affiliation(s)
- Sadanand Dangari Akshay
- Nitte (Deemed to be University), Nitte University Centre for Science Education and Research, Department of Bio & Nano Technology, Paneer Campus, Deralakatte, Mangalore-575018, India
| | - Vijaya Kumar Deekshit
- Nitte (Deemed to be University), Nitte University Centre for Science Education and Research, Department of Infectious Diseases & Microbial Genomics, Paneer Campus, Deralakatte, Mangalore-575018, India
| | - Juliet Mohan Raj
- Nitte (Deemed to be University), Nitte University Centre for Science Education and Research, Department of Infectious Diseases & Microbial Genomics, Paneer Campus, Deralakatte, Mangalore-575018, India
| | - Biswajit Maiti
- Nitte (Deemed to be University), Nitte University Centre for Science Education and Research, Department of Bio & Nano Technology, Paneer Campus, Deralakatte, Mangalore-575018, India
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Nayak S, Aanice D, Andria D, Pai A, Maiti B. Polymerase chain reaction-based typing methods and protein profiling analysis of Acinetobacter baumannii isolated from environmental and clinical sources from South India. Can J Microbiol 2023; 69:449-462. [PMID: 37364377 DOI: 10.1139/cjm-2023-0010] [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] [Indexed: 06/28/2023]
Abstract
Acinetobacter baumannii is an opportunistic pathogen known for causing hospital-acquired infections. The natural habitat includes soil, water, sewage, and drains, but it is also detected in infected individuals' blood, pus, and respiratory pathways. Due to its resilient nature, it is known to be a causative agent for outbreaks. Therefore, it is crucial to understand the genetic similarity between clinical and environmental isolates. The study aimed to find the genetic relationships between clinical and environmental isolates using PCR-based typing methods such as enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR), random amplified polymorphic DNA (RAPD), and repetitive extragenic palindromic sequence-based PCR (Rep-PCR). Additionally, outer membrane protein (OMP) and whole cell protein (WCP) profiles were also used. The PCR-based methods, ERIC-PCR and Rep-PCR, showed decreased genetic similarity between clinical and environmental isolates (66% and 58%, respectively). However, RAPD showed relatively higher genetic similarity (91%). The OMP and WCP profiles showed varied banding patterns between the clinical and environmental isolates in the 29-43 kDa region. The PCR-based methods proved to be a reliable and reproducible technique. The OMP and WCP profiles, though not as discriminatory as the molecular typing methods, could help identify the most and least commonly occurring protein bands and thus help in typing clinical and environmental A. baumannii isolates.
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Affiliation(s)
- Srajana Nayak
- Nitte (Deemed to be University), Division of Infectious Diseases, Nitte University Centre for Science Education and Research (NUCSER), Deralakatte, Mangaluru, Karnataka 575018, India
| | - D'Almeida Aanice
- Nitte (Deemed to be University), Division of Infectious Diseases, Nitte University Centre for Science Education and Research (NUCSER), Deralakatte, Mangaluru, Karnataka 575018, India
| | - Dsouza Andria
- Nitte (Deemed to be University), Division of Infectious Diseases, Nitte University Centre for Science Education and Research (NUCSER), Deralakatte, Mangaluru, Karnataka 575018, India
| | - Archana Pai
- Nitte (Deemed to be University), Division of Infectious Diseases, Nitte University Centre for Science Education and Research (NUCSER), Deralakatte, Mangaluru, Karnataka 575018, India
| | - Biswajit Maiti
- Nitte (Deemed to be University), Division of Infectious Diseases, Nitte University Centre for Science Education and Research (NUCSER), Deralakatte, Mangaluru, Karnataka 575018, India
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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.
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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
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Akshay SD, Nayak S, Deekshit VK, Rohit A, Maiti B. Differential expression of outer membrane proteins and quinolone resistance determining region mutations can lead to ciprofloxacin resistance in Salmonella Typhi. Arch Microbiol 2023; 205:136. [PMID: 36961627 DOI: 10.1007/s00203-023-03485-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 01/17/2023] [Accepted: 03/13/2023] [Indexed: 03/25/2023]
Abstract
Multi-drug resistance in Salmonella Typhi remains a public health concern globally. This study aimed to investigate the function of quinolone resistance determining region (QRDR) of gyrA and parC in ciprofloxacin (CIP) resistant isolates and examine the differential expression of outer membrane proteins (OMPs) on exposure to sub-lethal concentrations of CIP in S. Typhi. The CIP-resistant isolates were screened for mutations in the QRDR and analyzed for bacterial growth. Furthermore, major OMPs encoding genes such as ompF, lamB, yaeT, tolC, ompS1, and phoE were examined for differential expression under the sub-lethal concentrations of CIP by real-time PCR and SDS-PAGE. Notably, our study has shown a single-point mutation in gyrA at codon 83 (Ser83-tyrosine and Ser83-phenylalanine), also the rare amino acid substitution in parC gene at codon 80 (Glu80-glycine) in CIP-resistant isolates. Additionally, CIP-resistant isolates showed moderate growth compared to susceptible isolates. Although most of the OMP-encoding genes (tolC, ompS1, and phoE) showed some degree of upregulation, a significant level of upregulation (p < 0.05) was observed only for yaeT. However, ompF and lamB genes were down-regulated compared to CIP-susceptible isolates. Whereas OMPs profiling using SDS-PAGE did not show any changes in the banding pattern. These results provide valuable information on the QRDR mutation, and the difference in the growth, and expression of OMP-encoding genes in resistant and susceptible isolates of S. Typhi. This further provides insight into the involvement of QRDR mutation and OMPs associated with CIP resistance in S. Typhi.
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Affiliation(s)
- Sadanand Dangari Akshay
- Division of Infectious Diseases, Nitte (Deemed to Be University), Nitte University Centre for Science Education and Research (NUCSER), Paneer Campus, Deralakatte, Mangalore, 575018, India
| | - Srajana Nayak
- Division of Infectious Diseases, Nitte (Deemed to Be University), Nitte University Centre for Science Education and Research (NUCSER), Paneer Campus, Deralakatte, Mangalore, 575018, India
| | - Vijaya Kumar Deekshit
- Division of Infectious Diseases, Nitte (Deemed to Be University), Nitte University Centre for Science Education and Research (NUCSER), Paneer Campus, Deralakatte, Mangalore, 575018, India
| | - Anusha Rohit
- Division of Infectious Diseases, Nitte (Deemed to Be University), Nitte University Centre for Science Education and Research (NUCSER), Paneer Campus, Deralakatte, Mangalore, 575018, India
- Department of Microbiology, The Madras Medical Mission, 4-A, Dr, Mogappair, Chennai, Tamil Nadu, 600037, India
| | - Biswajit Maiti
- Division of Infectious Diseases, Nitte (Deemed to Be University), Nitte University Centre for Science Education and Research (NUCSER), Paneer Campus, Deralakatte, Mangalore, 575018, India.
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Aditya V, Kotian A, Sanil A, Thaseena PMA, Karunasagar I, Deekshit VK. Survival and Virulence Potential of Drug-Resistant E. coli in Simulated Gut Conditions and Antibiotic Challenge. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:12805. [PMID: 36232102 PMCID: PMC9566084 DOI: 10.3390/ijerph191912805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 09/28/2022] [Accepted: 10/01/2022] [Indexed: 06/16/2023]
Abstract
The gut forms a vital niche for the survival and replication of drug-resistant E. coli; however, the role of gut conditions on drug-resistant and sensitive E. coli is not clearly understood. The study aims to understand the effect of in vitro gut conditions on the spread of antibiotic resistance among E. coli and their ability to adapt to gut conditions. In this study, a multidrug-resistant (J51) and a sensitive (J254) E. coli isolate were exposed to a series of in vitro gut conditions and their growth pattern, virulence gene expression and invasion ability were studied. Further, the effect of antibiotic under in vitro gut conditions was also studied. Bile significantly affected the growth of the isolates, and the addition of iron chelator extended the lag phase of the sensitive isolate. Each in vitro gut condition had a differential effect on the expression of virulence genes in both the isolates. Further, the resistant isolate could adhere to and invade Caco2 cell lines better than the sensitive isolate. Most of the downregulated genes showed increased expression upon ciprofloxacin shock under in vitro gut conditions. The transcriptomics study revealed that exposure to bile, led to the downregulation of genes involved in different metabolic pathways. Further downregulation of metabolic pathways on ciprofloxacin shock was also observed. The downregulation of metabolic pathways could be a part of the global response played by the bacteria to adapt to harsh conditions. Reverting these fluctuated pathways could prove to be a novel strategy in combating AMR threat. Overall, bile, in high and low temperature conditions, showed a significant effect on modulating virulence gene expression on the antibiotic challenge. Thus, it is essential to consider the impact of gut conditions on gut pathogens, such as E. coli, before prescribing antimicrobial therapy during infection.
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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
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