The impact of DNA adenine methyltransferase knockout on the development of triclosan resistance and antibiotic cross-resistance in Escherichia coli.
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ABSTRACT: Background
DNA adenine methyltransferase (dam) has been well documented for its role in regulation of replication, mismatch repair and transposition. Recent studies have also suggested a role for dam in protection against antibiotic stress, although this is not yet fully defined. We therefore evaluated the role of dam in the development of antibiotic resistance and triclosan-associated cross-resistance.Results
A significant impact on growth rate was seen in the dam knockout compared to the parental strain. Known triclosan resistance-associated mutations in fabI were seen regardless of dam status, with an additional mutation in lrhA seen in the dam knockout. The expression of multiple antibiotic resistance-associated genes was significantly different between the parent and dam knockout post-resistance induction. Reversion rate assays showed that resistance mechanisms were stable.Conclusions
dam knockout had a significant effect on growth, but its role in the development of antibiotic resistance is likely confined to those antibiotics using acrAD-containing efflux pumps.
SUBMITTER: Hughes L
PROVIDER: S-EPMC8115981 | biostudies-literature |
REPOSITORIES: biostudies-literature
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