255L

HYDROLASE

255L の概要

• エントリーDOI: 10.2210/pdb255l/pdb
• 分子名称: LYSOZYME, CHLORIDE ION, BETA-MERCAPTOETHANOL, ... (4 entities in total)
• 機能のキーワード: hydrolase, glycosidase, bacteriolytic enzyme
• 由来する生物種: Enterobacteria phage T4
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 18776.42

構造登録者

Kuroki, R.,Shoichet, B.,Weaver, L.H.,Matthews, B.W. (登録日: 1997-11-10, 公開日: 1998-01-28, 最終更新日: 2024-05-22)

主引用文献

Shoichet, B.K.,Baase, W.A.,Kuroki, R.,Matthews, B.W.
A relationship between protein stability and protein function.
Proc.Natl.Acad.Sci.USA, 92:452-456, 1995

PubMed Abstract: Enzymes are thought to use their ordered structures to facilitate catalysis. A corollary of this theory suggests that enzyme residues involved in function are not optimized for stability. We tested this hypothesis by mutating functionally important residues in the active site of T4 lysozyme. Six mutations at two catalytic residues, Glu-11 and Asp-20, abolished or reduced enzymatic activity but increased thermal stability by 0.7-1.7 kcal.mol-1. Nine mutations at two substrate-binding residues, Ser-117 and Asn-132, increased stability by 1.2-2.0 kcal.mol-1, again at the cost of reduced activity. X-ray crystal structures show that the substituted residues complement regions of the protein surface that are used for substrate recognition in the native enzyme. In two of these structures the enzyme undergoes a general conformational change, similar to that seen in an enzyme-product complex. These results support a relationship between stability and function for T4 lysozyme. Other evidence suggests that the relationship is general.

PubMed: 7831309
DOI: 10.1073/pnas.92.2.452

実験手法

X-RAY DIFFRACTION (1.8 Å)