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1j0y
From Proteopedia
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beta-amylase from Bacillus cereus var. mycoides in complex with glucose
Overview
The crystal structures of beta-amylase from Bacillus cereus var. mycoides in complexes with five inhibitors were solved. The inhibitors used were three substrate analogs, i.e. glucose, maltose (product), and a synthesized compound, O-alpha-D-glucopyranosyl-(1-->4)-O-alpha-D-glucopyranosyl-(1-->4)-D-xylopy ranose (GGX), and two affinity-labeling reagents with an epoxy alkyl group at the reducing end of glucose. For all inhibitors, one molecule was bound at the active site cleft and the non-reducing end glucose of the four inhibitors except GGX was located at subsite 1, accompanied by a large conformational change of the flexible loop (residues 93-97), which covered the bound inhibitor. In addition, another molecule of maltose or GGX was bound about 30 A away from the active site. A large movement of residues 330 and 331 around subsite 3 was also observed upon the binding of GGX at subsites 3 to 5. Two affinity-labeling reagents, alpha-EPG and alpha-EBG, were covalently bound to a catalytic residue (Glu-172). A substrate recognition mechanism for the beta-amylase was discussed based on the modes of binding of these inhibitors in the active site cleft.
About this Structure
1J0Y is a Single protein structure of sequence from Bacillus cereus with and as ligands. Active as Beta-amylase, with EC number 3.2.1.2 Full crystallographic information is available from OCA.
Reference
Crystal structures of beta-amylase from Bacillus cereus var mycoides in complexes with substrate analogs and affinity-labeling reagents., Oyama T, Miyake H, Kusunoki M, Nitta Y, J Biochem. 2003 Apr;133(4):467-74. PMID:12761294
Page seeded by OCA on Thu Feb 21 13:17:46 2008
