1CHD

CHEB METHYLESTERASE DOMAIN

Summary for 1CHD

• Entry DOI: 10.2210/pdb1chd/pdb
• Descriptor: CHEB METHYLESTERASE (2 entities in total)
• Functional Keywords: chemotaxis protein, serine hydrolase, carboxyl methylesterase
• Biological source: Salmonella typhimurium
• Cellular location: Cytoplasm: P04042
• Total number of polymer chains: 1
• Total formula weight: 21457.72

Authors

West, A.H.,Martinez-Hackert, E.,Stock, A.M. (deposition date: 1995-03-09, release date: 1996-01-29, Last modification date: 2024-02-07)

Primary citation

West, A.H.,Martinez-Hackert, E.,Stock, A.M.
Crystal structure of the catalytic domain of the chemotaxis receptor methylesterase, CheB.
J.Mol.Biol., 250:276-290, 1995

PubMed Abstract: Signaling activity of bacterial chemotaxis transmembrane receptors is modulated by reversible covalent modification of specific receptor glutamate residues. The level of receptor methylation results from the activities of a specific S-adenosylmethionine-dependent methyltransferase, CheR, and the CheB methylesterase, which catalyzes hydrolysis of receptor glutamine or methylglutamate side-chains to glutamic acid. The CheB methylesterase belongs to a large family of response regulator proteins in which N-terminal regulatory domains control the activities of C-terminal effector domains. The crystal structure of the catalytic domain of the Salmonella typhimurium CheB methylesterase has been determined at 1.75 A resolution. The domain has a modified, doubly wound alpha/beta fold in which one of the helices is replaced by an anti-parallel beta-hairpin. Previous biochemical and mutagenesis data, suggest that the methylester hydrolysis catalyzed by CheB proceeds through a mechanism involving a serine nucleophile. The methylesterase active site is tentatively identified as a cleft at the C-terminal edge of the beta-sheet containing residues Ser164, His190 and Asp286. The three-dimensional fold, and the arrangement of residues within the catalytic triad distinguishes the CheB methylesterase from any previously described serine protease or serine hydrolase.

PubMed: 7608974
DOI: 10.1006/jmbi.1995.0376

Experimental method

X-RAY DIFFRACTION (1.75 Å)