First report of VIM metallo-β-lactamase production in Escherichia coli and Klebsiella pneumoniae clinical isolates from Gaza Strip, Palestine

Regulation of Carbapenemase Gene Conjugation in Escherichia coli Clinical Isolates

Background: The purpose of this study is to raise awareness of the hazards of carbapenemase epidemics and provide theoretical support for preventing the spread of carbapenemase-producing organisms. Methods: A total of 893 non-duplicate E. coil strains were recruited from three major local hospitals. The carbapenemase genotype of each imipenem-resistant strain was analyzed. Molecular typing and homology analysis of the main carbapenemase-producing strains reveal the transmission mode of resistance genes. Through the conjugation experiment, the potential spreading risk of carbapenemase genes was analyzed. Extended-spectrum beta-lactamase genes and replicon detection of the conjugant carrying plasmid were performed. The unannotated Escherichia coli bacterial small non-coding RNAs (sRNAs) interacting with sdiA were predicted through a bioinformatics tool. The sRNAs overexpression and knockout strains were constructed, and the effect of sRNA on conjugation was analyzed. Results: A total of 8 carbapenemase-producing strains were detected (0.90%, 8/893). The main carbapenemase genotype was bla_{KPC -2} (7 strains). Multilocus sequence typing indicated that 7 E. coli isolates belonged to ST-10, ST-101, ST-131, ST-405, ST-410, and ST-1193, ST-2562, respectively. Homologous cluster analysis revealed that the sequence types among the 7 E. coli were high diversity. The bla_{KPC -2} genes were successfully transferred from these isolates to EC600 by conjugation. All transconjugant cells exhibited significantly reduced susceptibility to the imipenem. IncFII was the most common conjugative plasmid type (85.7%, 6/7). Bioinformatics predicted the interaction between RydB and sdiA. Further experiments found that the interaction between RydB and sdiA improved the bacterial conjugation rate between MG1655 and EC600. The regulation effect of RydB on E. coli conjugation was not affected by the replicon type and/or harboring resistance coding genotype in conjugative plasmids. Conclusion: Our findings emphasized the epidemiological characteristics of carbapenemase-resistant E. coli. A functional phenotype of the new sRNA RydB was identified, and the regulation effect of RydB on E. coli conjugation was improved.

Prevalence and molecular epidemiology of carbapenem-resistant Gram-negative bacilli and their resistance determinants in the Eastern Mediterranean Region over the last decade

Carbapenem resistance in Enterobacteriaceae, Acinetobacter baumannii and Pseudomonas aeruginosa is increasing worldwide, which has led the World Health Organization (WHO) to list these bacteria in the critical priority pathogens group. Infections by such pathogens pose a serious threat to hospitalised patients and are associated with clinical and economic consequences. What worsens the case is the weak pipeline of available antimicrobial agents to treat such infections and the absence of new drugs. The aim of this review was to shed light on all studies tackling carbapenem resistance in Enterobacteriaceae, A. baumannii and P. aeruginosa in the Eastern Mediterranean region, with indication for each country, description of studies timeline, prevalence of carbapenem resistance, and carbapenem resistance-encoding genes detected in these countries.