1A2O

STRUCTURAL BASIS FOR METHYLESTERASE CHEB REGULATION BY A PHOSPHORYLATION-ACTIVATED DOMAIN

1A2O の概要

• エントリーDOI: 10.2210/pdb1a2o/pdb
• 分子名称: CHEB METHYLESTERASE (2 entities in total)
• 機能のキーワード: bacterial chemotaxis, adaptation, serine hydrolase
• 由来する生物種: Salmonella typhimurium
• 細胞内の位置: Cytoplasm: P04042
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 75197.70

構造登録者

Djordjevic, S.,Goudreau, P.N.,Xu, Q.,Stock, A.M.,West, A.H. (登録日: 1998-01-06, 公開日: 1998-04-29, 最終更新日: 2024-05-22)

主引用文献

Djordjevic, S.,Goudreau, P.N.,Xu, Q.,Stock, A.M.,West, A.H.
Structural basis for methylesterase CheB regulation by a phosphorylation-activated domain.
Proc.Natl.Acad.Sci.USA, 95:1381-1386, 1998

PubMed Abstract: We report the x-ray crystal structure of the methylesterase CheB, a phosphorylation-activated response regulator involved in reversible modification of bacterial chemotaxis receptors. Methylesterase CheB and methyltransferase CheR modulate signaling output of the chemotaxis receptors by controlling the level of receptor methylation. The structure of CheB, which consists of an N-terminal regulatory domain and a C-terminal catalytic domain joined by a linker, was solved by molecular replacement methods using independent search models for the two domains. In unphosphorylated CheB, the N-terminal domain packs against the active site of the C-terminal domain and thus inhibits methylesterase activity by directly restricting access to the active site. We propose that phosphorylation of CheB induces a conformational change in the regulatory domain that disrupts the domain interface, resulting in a repositioning of the domains and allowing access to the active site. Structural similarity between the two companion receptor modification enzymes, CheB and CheR, suggests an evolutionary and/or functional relationship. Specifically, the phosphorylated N-terminal domain of CheB may facilitate interaction with the receptors, similar to the postulated role of the N-terminal domain of CheR. Examination of surfaces in the N-terminal regulatory domain of CheB suggests that despite a common fold throughout the response regulator family, surfaces used for protein-protein interactions differ significantly. Comparison between CheB and other response regulators indicates that analogous surfaces are used for different functions and conversely, similar functions are mediated by different molecular surfaces.

PubMed: 9465023
DOI: 10.1073/pnas.95.4.1381

実験手法

X-RAY DIFFRACTION (2.4 Å)