This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1urx
From Proteopedia
|
CRYSTALLOGRAPHIC STRUCTURE OF BETA-AGARASE A IN COMPLEX WITH OLIGOAGAROSE
Overview
Agarose is a gel-forming polysaccharide with an alpha-L(1,4)-3,6-anhydro-galactose, beta-D(1,3)-galactose repeat unit, from the cell walls of marine red algae. beta-agarase A, from the Gram-negative bacterium Zobellia galactanivorans, is secreted to the external medium and degrades agarose with an endo-mechanism. The structure of the inactive mutant beta-agarase A-E147S in complex with agaro-octaose has been solved at 1.7 A resolution. Two oligosaccharide chains are bound to the protein. The first one resides in the active site channel, spanning subsites -4 to -1. A second oligosaccharide binding site, on the opposite side of the protein, was filled with eight sugar units, parallel to the active site. The crystal structure of the beta-agarase A with agaro-octaose provides detailed information on agarose recognition in the catalytic site. The presence of the second, parallel, binding site suggests that the enzyme might be able to unwind the double-helical structure of agarose prior to the catalytic cleavage.
About this Structure
1URX is a Single protein structure of sequence from Zobellia galactanivorans with as ligand. Active as Beta-agarase, with EC number 3.2.1.81 Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
Parallel substrate binding sites in a beta-agarase suggest a novel mode of action on double-helical agarose., Allouch J, Helbert W, Henrissat B, Czjzek M, Structure. 2004 Apr;12(4):623-32. PMID:15062085
Page seeded by OCA on Thu Feb 21 15:27:36 2008
