3ZTB: The Bacterial Stressosome: A Modular System That Has Been Adapted To Control Secondary Messenger Signaling

Citation:
Abstract
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.
PDB ID: 3ZTBDownload
MMDB ID: 97491
PDB Deposition Date: 2011/7/6
Updated in MMDB: 2012/02
Experimental Method:
x-ray diffraction
Resolution: 2.87  Å
Source Organism:
Similar Structures:
Biological Unit for 3ZTB: dimeric; determined by author and by software (PISA)
Molecular Components in 3ZTB
Label Count Molecule
Proteins (2 molecules)
2
Anti-sigma-factor Antagonist (Stas) Domain Protein
Molecule annotation
Chemicals (2 molecules)
1
2
* Click molecule labels to explore molecular sequence information.

Citing MMDB
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