1p4v
From Proteopedia
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CRYSTAL STRUCTURE OF THE GLYCOSYLASPARAGINASE PRECURSOR D151N MUTANT WITH GLYCINE
Overview
Glycosylasparaginase uses an autoproteolytic processing mechanism, through, an N-O acyl shift, to generate a mature/active enzyme from a single-chain, precursor. Structures of glycosylasparaginase precursors in complex with a, glycine inhibitor have revealed the backbone in the immediate vicinity of, the scissile peptide bond to be in a distorted trans conformation, which, is believed to be the driving force for the N-O acyl shift to break the, peptide bond. Here we report the effects of point mutation D151N. In, addition to the loss of the base essential in autoproteolysis, this, mutation also eradicates the backbone distortion near the scissile peptide, bond. Binding of the glycine inhibitor to the autoproteolytic site of the, D151N mutant does not restore the backbone distortion. Therefore, Asp151, plays a dual role, acting as the general base to activate the nucleophile, and holding the distorted trans conformation that is critical for, initiating an N-O acyl shift.
About this Structure
1P4V is a Single protein structure of sequence from Elizabethkingia meningoseptica with GLY as ligand. Active as N(4)-(beta-N-acetylglucosaminyl)-L-asparaginase, with EC number 3.5.1.26 Full crystallographic information is available from OCA.
Reference
A dual role for an aspartic acid in glycosylasparaginase autoproteolysis., Qian X, Guan C, Guo HC, Structure. 2003 Aug;11(8):997-1003. PMID:12906830
Page seeded by OCA on Tue Nov 20 23:28:36 2007
