5bca
From Proteopedia
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BETA-AMYLASE FROM BACILLUS CEREUS VAR. MYCOIDES
Overview
The crystal structure of beta-amylase from Bacillus cereus var. mycoides, was determined by the multiple isomorphous replacement method. The, structure was refined to a final R-factor of 0.186 for 102,807 independent, reflections with F/sigma(F) > or = 2.0 at 2.2 A resolution with, root-mean-square deviations from ideality in bond lengths, and bond angles, of 0.014 A and 3.00 degrees, respectively. The asymmetric unit comprises, four molecules exhibiting a dimer-of-dimers structure. The enzyme, however, acts as a monomer in solution. The beta-amylase molecule folds, into three domains; the first one is the N-terminal catalytic domain with, a (beta/alpha)8 barrel, the second one is the excursion part from the, first one, and the third one is the C-terminal domain with two almost, anti-parallel beta-sheets. The active site cleft, including two putative, catalytic residues (Glu172 and Glu367), is located on the carboxyl side of, the central beta-sheet in the (beta/alpha)8 barrel, as in most amylases., The active site structure of the enzyme resembles that of soybean, beta-amylase with slight differences. One calcium ion is bound per, molecule far from the active site. The C-terminal domain has a fold, similar to the raw starch binding domains of cyclodextrin, glycosyltransferase and glucoamylase.
About this Structure
5BCA is a Single protein structure of sequence from Bacillus cereus with as ligand. Active as Beta-amylase, with EC number 3.2.1.2 Known structural/functional Sites: , , and . Full crystallographic information is available from OCA.
Reference
Crystal structure of beta-amylase from Bacillus cereus var. mycoides at 2.2 A resolution., Oyama T, Kusunoki M, Kishimoto Y, Takasaki Y, Nitta Y, J Biochem (Tokyo). 1999 Jun;125(6):1120-30. PMID:10348915
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