Dataset Information

The impact of DNA adenine methyltransferase knockout on the development of triclosan resistance and antibiotic cross-resistance in Escherichia coli.

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 | 2021

REPOSITORIES: biostudies-literature

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Publications

The impact of DNA adenine methyltransferase knockout on the development of triclosan resistance and antibiotic cross-resistance in <i>Escherichia coli</i>.

Hughes Lewis L Roberts Wayne W Johnson Donna D

Access microbiology 20201118 1

<h4>Background</h4>DNA adenine methyltransferase (<i>dam</i>) has been well documented for its role in regulation of replication, mismatch repair and transposition. Recent studies have also suggested a role for <i>dam</i> in protection against antibiotic stress, although this is not yet fully defined. We therefore evaluated the role of <i>dam</i> in the development of antibiotic resistance and triclosan-associated cross-resistance.<h4>Results</h4>A significant impact on growth rate was seen in t ...[more]

PMID: 33997609

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