THE CRYSTAL STRUCTURE OF A LOW MOLECULAR PHOSPHOTYROSINE PROTEIN PHOSPHATASE
[PPAC_BOVIN] Acts on tyrosine phosphorylated proteins, low-MW aryl phosphates and natural and synthetic acyl phosphates.
Publication Abstract from PubMed
Protein tyrosine phosphorylation and dephosphorylation are central reactions for control of cellular division, differentiation and development. Here we describe the crystal structure of a low-molecular-weight phosphotyrosine protein phosphatase (PTPase), a cytosolic phosphatase present in many mammalian cells. The enzyme catalyses the dephosphorylation of phosphotyrosine-containing substrates, and overexpression of the protein in normal and transformed cells inhibits cell proliferation. The structure of the low-molecular-weight PTPase reveals an alpha/beta protein containing a phosphate-binding loop motif at the amino end of helix alpha 1. This motif includes the essential active-site residues Cys 12 and Arg 18 and bears striking similarities to the active-site motif recently described in the structure of human PTP1B. The structure of the low-molecular-weight PTPase supports a reaction mechanism involving the conserved Cys 12 as an attacking nucleophile in an in-line associative mechanism. The structure also suggests a catalytic role for Asp 129 in the reaction cycle.
The crystal structure of a low-molecular-weight phosphotyrosine protein phosphatase.,Su XD, Taddei N, Stefani M, Ramponi G, Nordlund P Nature. 1994 Aug 18;370(6490):575-8. PMID:8052313
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.