Adaptation to sustained nitrogen starvation by Escherichia coli requires the eukaryote-like serine/threonine kinase YeaG

• Published in: Scientific reports 2015-12, Vol.5 (1), p.17524, Article 17524
• Main Authors: Figueira, Rita, Brown, Daniel R., Ferreira, Delfim, Eldridge, Matthew J. G., Burchell, Lynn, Pan, Zhensheng, Helaine, Sophie, Wigneshweraraj, Sivaramesh
• Format: Article
• Language: English
• Subjects: 13/31; 38; 631/326; 631/337/572; Adaptation, Physiological; Antitoxins; Bacterial Proteins - genetics; Bacterial Proteins - metabolism; Bacterial Toxins - genetics; Bacterial Toxins - metabolism; DNA-Binding Proteins - genetics; DNA-Binding Proteins - metabolism; E coli; Escherichia coli; Escherichia coli K12 - enzymology; Escherichia coli K12 - genetics; Escherichia coli Proteins - genetics; Escherichia coli Proteins - metabolism; Gene Deletion; Gene expression; Gene silencing; Heterogeneity; Humanities and Social Sciences; Kinases; Metabolism; multidisciplinary; Nitrogen; Nitrogen - metabolism; Protein Serine-Threonine Kinases - genetics; Protein Serine-Threonine Kinases - metabolism; Protein-serine/threonine kinase; Science; Sigma Factor - genetics; Sigma Factor - metabolism; Stress response; Toxins
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep17524

The Escherichia coli eukaryote-like serine/threonine kinase, encoded by yeaG , is expressed in response to diverse stresses, including nitrogen (N) starvation. A role for yeaG in bacterial stress response is unknown. Here we reveal for the first time that wild-type E. coli displays metabolic heterogeneity following sustained periods of N starvation, with the metabolically active population displaying compromised viability. In contrast, such heterogeneity in metabolic activity is not observed in an E. coli ∆ yeaG mutant, which continues to exist as a single and metabolically active population and thus displays an overall compromised ability to survive sustained periods of N starvation. The mechanism by which yeaG acts, involves the transcriptional repression of two toxin/antitoxin modules, mqsR/mqsA and dinJ / yafQ . This, consequently, has a positive effect on the expression of rpoS , the master regulator of the general bacterial stress response. Overall, results indicate that yeaG is required to fully execute the rpoS -dependent gene expression program to allow E. coli to adapt to sustained N starvation and unravels a novel facet to the regulatory basis that underpins adaptive response to N stress.