Intersection of the stringent response and the CodY regulon in low GC Gram-positive bacteria.

Tobias Geiger, Christiane Wolz

Journal: International journal of medical microbiology : IJMM 2014;304(2):150-5

PMID: 24462007

Full Text on Elsevier Science View on PubMed

Abstract

Bacteria adapt efficiently to a wide range of nutritional environments. Therefore, they possess overlapping regulatory systems that detect intracellular pools of key metabolites. In low GC Gram-positive bacteria, two global regulators, the stringent response and the CodY repressor, respond to an intracellular decrease in amino acid content. Amino acid limitation leads to rapid synthesis of the alarmones pppGpp and ppGpp through the stringent response and inactivates the CodY repressor. Two cofactors, branched chain amino acids (BCAA) and GTP, are ligands for CodY and facilitate binding to the target DNA. Because (p)ppGpp synthesis and accumulation evidentially reduce the intracellular GTP pool, CodY is released from the DNA, and transcription of target genes is altered. Here, we focus on this intimate link between the stringent response and CodY regulation in different Gram-positive species.

Address: Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Germany.; Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Germany. Electronic address: [email protected].

DOI: 10.1016/j.ijmm.2013.11.013