Genomic investigation unveils colistin resistance mechanism in carbapenem-resistant Acinetobacter baumannii clinical isolates
Abstract
ABSTRACT Colistin resistance in Acinetobacter baumannii is mediated by multiple mechanisms. Recently, mutations within pmrABC two-component system and overexpression of eptA gene due to upstream insertion of IS Aba1 have been shown to play a major role. Thus, the aim of our study is to characterize colistin resistance mechanisms among the clinical isolates of A. baumannii in India. A total of 207 clinical isolates of A. baumannii collected from 2016 to 2019 were included in this study. Mutations within lipid A biosynthesis and pmrABC genes were characterized by whole-genome shotgun sequencing. Twenty-eight complete genomes were further characterized by hybrid assembly approach to study insertional inactivation of lpx genes and the association of IS Aba1-eptA . Several single point mutations (SNPs), like M12I in pmrA , A138T and A444V in pmrB , and E117K in lpxD, were identified. We are the first to report two novel SNPs (T7I and V383I) in the pmrC gene. Among the five colistin-resistant A. baumannii isolates where complete genome was available, the analysis showed that three of the five isolates had IS Aba1 insertion upstream of eptA . No mcr genes were identified among the isolates. We mapped the SNPs on the respective protein structures to understand the effect on the protein activity. We found that majority of the SNPs had little effect on the putative protein function; however, some SNPs might destabilize the local structure. Our study highlights the diversity of…
Read the paper
Related studies
- Severe clinical outcomes of COVID-19 associated with proton pump inhibitors: a nationwide cohort study with propensity score matching
- Levofloxacin-Induced Tendon Rupture: A Case Report and Review of the Literature
- Association between cord blood 25-hydroxyvitamin D concentrations and respiratory tract infections in the first 6 months of age in a Korean population: a birth cohort study (COCOA)
- Neuroprotective Effects of Epicatechin against Oxidative Stress-Induced Cognitive Impairment: A Systematic Review and Meta-Analysis
- Quality evaluation and in vitro interaction studies between levofloxacin 250mg and diclofenac sodium 50mg tablets
- Molecular Epidemiology of mcr-1 -Positive Polymyxin B-Resistant Escherichia coli Producing Extended-Spectrum β-Lactamase (ESBL) in a Tertiary Hospital in Shandong, China
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.