Positive allosteric feedback regulation of the stringent response enzyme RelA by its product.

Shyp V, Tankov S, Ermakov A, Kudrin P, English BP, Ehrenberg M, Tenson T, Elf J, Hauryliuk V

EMBO Rep. 13 (9) 835-839 [2012-09-00; online 2012-07-20]

During the stringent response, Escherichia coli enzyme RelA produces the ppGpp alarmone, which in turn regulates transcription, translation and replication. We show that ppGpp dramatically increases the turnover rate of its own ribosome-dependent synthesis by RelA, resulting in direct positive regulation of an enzyme by its product. Positive allosteric regulation therefore constitutes a new mechanism of enzyme activation. By integrating the output of individual RelA molecules and ppGpp degradation pathways, this regulatory circuit contributes to a fast and coordinated transition to stringency.

Affiliated researcher

PubMed 22814757

DOI 10.1038/embor.2012.106

Crossref 10.1038/embor.2012.106

pii: embor2012106
pmc: PMC3432798

Publications 9.5.0