3zt9

Publication Abstract from PubMed

The stressosome complex regulates downstream effectors in response to environmental signals. In Bacillus subtilis, it activates the alternative sigma factor sigma(B), leading to the upregulation of the general stress regulon. Herein, we characterize a stressosome-regulated biochemical pathway in Moorella thermoacetica. We show that the presumed sensor, MtR, and the scaffold, MtS, form a pseudo-icosahedral structure like that observed in B. subtilis. The N-terminal domain of MtR is structurally homologous to B. subtilis RsbR, despite low sequence identity. The affinity of the switch kinase, MtT, for MtS decreases following MtS phosphorylation and not because of structural reorganization. Dephosphorylation of MtS by the PP2C type phosphatase MtX permits the switch kinase to rebind the stressosome to reset the response. We also show that MtT regulates cyclic di-GMP biosynthesis through inhibition of a GG(D/E)EF-type diguanylate cyclase, demonstrating that secondary messenger levels are regulated by the stressosome.

The Bacterial Stressosome: A Modular System that Has Been Adapted to Control Secondary Messenger Signaling.,Quin MB, Berrisford JM, Newman JA, Basle A, Lewis RJ, Marles-Wright J Structure. 2012 Feb 8;20(2):350-63. PMID:22325782^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.