English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Background  The issue of carbapenem resistance in  E.coli  is very concerning and it is speculated that cumulative effect of both primary resistance genes and secondary resistance genes that act as helper to the primary resistance genes are the reason behind their aggravation. Therefore, here we attempted to find the role of two secondary resistance genes (SRG)  ccdB  and  repA2  in carbapenem resistance in  E. coli  (CRE). In this context influential genes belonging to secondary resistome that act as helper to the primary resistance genes like  bla  NDM  and  bla  CTX-M  in aggravating β-lactam resistance were selected from an earlier reported in silico study. Transcriptional expression of the selected genes in clinical isolates of  E.coli  that were discretely harboring  bla  NDM-1 ,  bla  NDM-4 ,  bla  NDM-5 ,  bla  NDM-7  and  bla  CTX-M-15  with and without carbapenem and cephalosporin stress (2 μg/ml) was determined by real time PCR. Cured mutants sets that were lacking (i) primary resistance genes, (ii) secondary resistance genes and (iii) both primary and secondary resistance genes were prepared by SDS treatment. These sets were then subjected to antibiotic susceptibility testing by Kirby Bauer disc diffusion method.    Results  Out of the 21 genes reported in the in silico study, 2 genes viz .   repA2  and  ccdB  were selected for transcriptional expression analysis.  repA2,  coding replication regulatory protein, was downregulated in response to carbapenems and cephalosporins.  ccdB , coding for plasmid maintenance protein, was also downregulated in response to carbapenems except imipenem and cephalosporins. Following plasmid elimination assay increase in diameter of zone of inhibition under stress of both antibiotics was observed as compared to uncured control hinting at the reversion of antibiotic susceptibility by the-then resistant bacteria.    Conclusion  SRGs  repA2  and  ccdB  help sustenance of  bla  NDM  and  bla  CTX-M  under carbapenem and cephalosporin stress.    Supplementary Information  The online version contains supplementary material available at 10.1186/s12866-021-02136-y.

Transcriptional expression of secondary resistance genes ccdB and repA2 is enhanced in presence of cephalosporin and carbapenem in Escherichia coli