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Global tRNA misacylation induced by anaerobiosis and antibiotic exposure broadly increases stress resistance in Escherichia coli.

ABSTRACT: High translational fidelity is commonly considered a requirement for optimal cellular health and protein function. However, recent findings have shown that inducible mistranslation specifically with methionine engendered at the tRNA charging level occurs in mammalian cells, yeast and archaea, yet it was unknown whether bacteria were capable of mounting a similar response. Here, we demonstrate that Escherichia coli misacylates non-methionyl-tRNAs with methionine in response to anaerobiosis and antibiotic exposure via the methionyl-tRNA synthetase (MetRS). Two MetRS succinyl-lysine modifications independently confer high tRNA charging fidelity to the otherwise promiscuous, unmodified enzyme. Strains incapable of tRNA mismethionylation are less adept at growth in the presence of antibiotics and stressors. The presence of tRNA mismethionylation and its potential role in mistranslation within the bacterial domain establishes this response as a pervasive biological mechanism and connects it to diverse cellular functions and modes of fitness.

SUBMITTER: Schwartz MH

PROVIDER: S-EPMC5137444 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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Global tRNA misacylation induced by anaerobiosis and antibiotic exposure broadly increases stress resistance in Escherichia coli.

Schwartz Michael H MH Waldbauer Jacob R JR Zhang Lichun L Pan Tao T

Nucleic acids research 20160926 21

High translational fidelity is commonly considered a requirement for optimal cellular health and protein function. However, recent findings have shown that inducible mistranslation specifically with methionine engendered at the tRNA charging level occurs in mammalian cells, yeast and archaea, yet it was unknown whether bacteria were capable of mounting a similar response. Here, we demonstrate that Escherichia coli misacylates non-methionyl-tRNAs with methionine in response to anaerobiosis and an ...[more]

PMID: 27672035

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Dataset Information

Global tRNA misacylation induced by anaerobiosis and antibiotic exposure broadly increases stress resistance in Escherichia coli.

Publications

Global tRNA misacylation induced by anaerobiosis and antibiotic exposure broadly increases stress resistance in Escherichia coli.

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