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Modulation of Escherichia coli Translation by the Specific Inactivation of tRNA^Gly Under Oxidative Stress.

ABSTRACT: Bacterial oxidative stress responses are generally controlled by transcription factors that modulate the synthesis of RNAs with the aid of some sRNAs that control the stability, and in some cases the translation, of specific mRNAs. Here, we report that oxidative stress additionally leads to inactivation of tRNA^Gly in Escherichia coli, inducing a series of physiological changes. The observed inactivation of tRNA^Gly correlated with altered efficiency of translation of Gly codons, suggesting a possible mechanism of translational control of gene expression under oxidative stress. Changes in translation also depended on the availability of glycine, revealing a mechanism whereby bacteria modulate the response to oxidative stress according to the prevailing metabolic state of the cells.

SUBMITTER: Leiva LE

PROVIDER: S-EPMC7461829 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Modulation of Escherichia coli Translation by the Specific Inactivation of tRNAGly Under Oxidative Stress.

Leiva Lorenzo Eugenio LE Pincheira Andrea A Elgamal Sara S Kienast Sandra D SD Bravo Verónica V Leufken Johannes J Gutiérrez Daniela D Leidel Sebastian A SA Ibba Michael M Katz Assaf A

Frontiers in genetics 20200818

Bacterial oxidative stress responses are generally controlled by transcription factors that modulate the synthesis of RNAs with the aid of some sRNAs that control the stability, and in some cases the translation, of specific mRNAs. Here, we report that oxidative stress additionally leads to inactivation of tRNAGly in Escherichia coli, inducing a series of physiological changes. The observed inactivation of tRNAGly correlated with altered efficiency of translation of ...[more]

PMID: 33014012

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