1WPR

Crystal structure of RsbQ inhibited by PMSF

Summary for 1WPR

• Entry DOI: 10.2210/pdb1wpr/pdb
• Related: 1WOM
• Descriptor: Sigma factor sigB regulation protein rsbQ, phenylmethanesulfonic acid, GLYCEROL, ... (4 entities in total)
• Functional Keywords: alpha/beta hydrolase, signaling protein
• Biological source: Bacillus subtilis
• Total number of polymer chains: 2
• Total formula weight: 61101.40

Authors

Kaneko, T.,Tanaka, N.,Kumasaka, T. (deposition date: 2004-09-11, release date: 2005-02-01, Last modification date: 2011-07-13)

Primary citation

Kaneko, T.,Tanaka, N.,Kumasaka, T.
Crystal structures of RsbQ, a stress-response regulator in Bacillus subtilis
Protein Sci., 14:558-565, 2005

PubMed Abstract: Growth-limiting stresses in bacteria induce the general stress response to protect the cells against future stresses. Energy stress caused by starvation conditions in Bacillus subtilis is transmitted to the sigma(B) transcription factor by stress-response regulators. RsbP, a positive regulator, is a phosphatase containing a PAS (Per-ARNT-Sim) domain and requires catalytic function of a putative alpha/beta hydrolase, RsbQ, to be activated. These two proteins have been found to interact with each other. We determined the crystal structures of RsbQ in native and inhibitor-bound forms to investigate why RsbP requires RsbQ. These structures confirm that RsbQ belongs to the alpha/beta hydrolase superfamily. Since the catalytic triad is buried inside the molecule due to the closed conformation, the active site is constructed as a hydrophobic cavity that is nearly isolated from the solvent. This suggests that RsbQ has specificity for a hydrophobic small compound rather than a macromolecule such as RsbP. Moreover, structural comparison with other alpha/beta hydrolases demonstrates that a unique loop region of RsbQ is a likely candidate for the interaction site with RsbP, and the interaction might be responsible for product release by operating the hydrophobic gate equipped between the cavity and the solvent. Our results support the possibility that RsbQ provides a cofactor molecule for the mature functionality of RsbP.

PubMed: 15632289
DOI: 10.1110/ps.041170005

Experimental method

X-RAY DIFFRACTION (2.6 Å)