脱磷
蛋白质酪氨酸磷酸酶
残留物(化学)
活动站点
酪氨酸
磷酸酶
半胱氨酸
双特异性磷酸酶
结合位点
化学
生物化学
酶
立体化学
作者
David Barford,Andrew Flint,Nicholas K. Tonks
出处
期刊:Science
[American Association for the Advancement of Science]
日期:1994-03-11
卷期号:263 (5152): 1397-1404
被引量:749
标识
DOI:10.1126/science.8128219
摘要
Protein tyrosine phosphatases (PTPs) constitute a family of receptor-like and cytoplasmic signal transducing enzymes that catalyze the dephosphorylation of phosphotyrosine residues and are characterized by homologous catalytic domains. The crystal structure of a representative member of this family, the 37-kilodalton form (residues 1 to 321) of PTP1B, has been determined at 2.8 A resolution. The enzyme consists of a single domain with the catalytic site located at the base of a shallow cleft. The phosphate recognition site is created from a loop that is located at the amino-terminus of an alpha helix. This site is formed from an 11-residue sequence motif that is diagnostic of PTPs and the dual specificity phosphatases, and that contains the catalytically essential cysteine and arginine residues. The position of the invariant cysteine residue within the phosphate binding site is consistent with its role as a nucleophile in the catalytic reaction. The structure of PTP1B should serve as a model for other members of the PTP family and as a framework for understanding the mechanism of tyrosine dephosphorylation.
科研通智能强力驱动
Strongly Powered by AbleSci AI