1ahp

From Proteopedia

Revision as of 12:43, 30 October 2007

OLIGOSACCHARIDE SUBSTRATE BINDING IN ESCHERICHIA COLI MALTODEXTRIN PHSPHORYLASE

Overview

The crystal structure of E. coli maltodextrin phosphorylase, co-crystallized with an oligosaccharide has been solved at 3.0 A, resolution, providing the first structure of an oligosaccharide bound at, the catalytic site of an alpha-glucan phosphorylase. An induced fit, mechanism brings together two domains across the catalytic site tunnel. A, stacking interaction between the glucosyl residue and the aromatic group, of a tyrosine residue at a sub-site remote (8 A) from the catalytic site, provides a key element in substrate recognition; mutation of this residue, to Ala decreases the Kcat/Km by 10(4). Extrapolation of the results to, substrate binding across the site of attack by phosphorolysis indicates a, likely alteration in the glycosidic torsion angles from their preferred, values, an ... [(full description)]

About this Structure

1AHP is a [Single protein] structure of sequence from [Escherichia coli] with MAL, SO4, PLP and GOL as [ligands]. Active as [Phosphorylase], with EC number [2.4.1.1]. Structure known Active Site: 1. Full crystallographic information is available from [OCA].

Reference

Oligosaccharide substrate binding in Escherichia coli maltodextrin phosphorylase., O'Reilly M, Watson KA, Schinzel R, Palm D, Johnson LN, Nat Struct Biol. 1997 May;4(5):405-12. PMID:9145112

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