Regulation of the opposing (p)ppGpp synthetase and hydrolase activities in a bifunctional RelA/SpoT homologue from Staphylococcus aureus.

ABSTRACT: The stringent response is characterized by (p)ppGpp synthesis resulting in repression of translation and reprogramming of the transcriptome. In Staphylococcus aureus, (p)ppGpp is synthesized by the long RSH (RelA/SpoT homolog) enzyme, RelSau or by one of the two short synthetases (RelP, RelQ). RSH enzymes are characterized by an N-terminal enzymatic domain bearing distinct motifs for (p)ppGpp synthetase or hydrolase activity and a C-terminal regulatory domain (CTD) containing conserved motifs (TGS, DC and ACT). The intramolecular switch between synthetase and hydrolase activity of RelSau is crucial for the adaption of S. aureus to stress (stringent) or non-stress (relaxed) conditions. We elucidated the role of the CTD in the enzymatic activities of RelSau. Growth pattern, transcriptional a

SUBMITTER: Gratani FL 

PROVIDER: S-EPMC6053245 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature