A silent network's resounding success: how mutations of core metabolic genes confer antibiotic resistance.
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ABSTRACT:
SUBMITTER: Wareth G
PROVIDER: S-EPMC8361174 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Although metabolism plays an active role in antibiotic lethality, antibiotic resistance is generally associated with drug target modification, enzymatic inactivation, and/or transport rather than metabolic processes. Evolution experiments of Escherichia coli rely on growth-dependent selection, which may provide a limited view of the antibiotic resistance landscape. We sequenced and analyzed E. coli adapted to representative antibiotics at increasingly heightened metabolic states. This revealed various underappreciated noncanonical genes, such as those related to central carbon and energy metabolism, which are implicated in antibiotic resistance. These metabolic alterations lead to lower basal respiration, which prevents antibiotic-mediated induction of tricarboxylic acid cycle activity, thus avoiding metabolic toxicity and minimizing drug lethality. Several of the identified metabolism-specific mutations are overrepresented in the genomes of >3500 clinical E. coli pathogens, indicating clinical relevance.
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Project description:We performed RNA-seq experiments to compare the gene expression profiles of cells expressing single-codon substitutions in the antibiotic resistance genes NDM-1, CAT-I, or aadB in the absence of antibiotics. Mutations with deleterious fitness effects in the absense of antibiotics also caused significant changes in gene expression in a number of genes related to stress-response pathways including the regulator of colanic acid capsule synthesis (Rcs) response, the phage shock protein response (Psp), and the oxidative stress response. Fold differences in gene expression were mutation- and gene-dependent.
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