 |
|
|
 |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
516 a.a.
_CA
Key reference
J Biochem (tokyo) 125:1120-1130 (1999) PubMed id: 10348915
Crystal structure of beta-amylase from Bacillus cereus var. mycoides at 2.2 A resolution. T.Oyama, M.Kusunoki, Y.Kishimoto, Y.Takasaki, Y.Nitta. ABSTRACT
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.
Literature references that cite this PDB file's key reference
PubMed id Reference
16262690 M.Machovic, B.Svensson, E.A.MacGregor, and S.Janecek (2005).
A new clan of CBM families based on bioinformatics of starch-binding domains from families CBM20 and CBM21.FEBS J, 272, 5497-5513.
11272837 Y.Mezaki, Y.Katsuya, M.Kubota, and Y.Matsuura (2001).
Crystallization and structural analysis of intact maltotetraose-forming exo-amylase from Pseudomonas stutzeri.Biosci Biotechnol Biochem, 65, 222-225.
PDB code: 1gcy The most recent references are shown first. Citation data come partly from CiteXplore and partly from an automated harvesting procedure. Note that this is likely to be only a partial list as not all journals are covered by either method. However, we are continually building up the citation data so more and more references will be included with time. Where a reference describes a PDB structure, the PDB code is shown on the right.
