1BFN

BETA-AMYLASE/BETA-CYCLODEXTRIN COMPLEX

Summary for 1BFN

• Entry DOI: 10.2210/pdb1bfn/pdb
• Related PRD ID: PRD_900012
• Descriptor: BETA-AMYLASE, Cycloheptakis-(1-4)-(alpha-D-glucopyranose), SULFATE ION, ... (4 entities in total)
• Functional Keywords: hydrolase, beta-amylase, beta-cyclodextrin, recombinant
• Biological source: Glycine max (soybean)
• Total number of polymer chains: 1
• Total formula weight: 57214.24

Authors

Adachi, M.,Mikami, B.,Katsube, T.,Utsumi, S. (deposition date: 1998-05-22, release date: 1998-10-28, Last modification date: 2024-02-07)

Primary citation

Adachi, M.,Mikami, B.,Katsube, T.,Utsumi, S.
Crystal structure of recombinant soybean beta-amylase complexed with beta-cyclodextrin.
J.Biol.Chem., 273:19859-19865, 1998

PubMed Abstract: In order to study the interaction of soybean beta-amylase with substrate, we solved the crystal structure of beta-cyclodextrin-enzyme complex and compared it with that of alpha-cyclodextrin-enzyme complex. The enzyme was expressed in Escherichia coli at a high level as a soluble and catalytically active protein. The purified recombinant enzyme had properties nearly identical to those of native soybean beta-amylase and formed the same crystals as the native enzyme. The crystal structure of recombinant enzyme complexed with beta-cyclodextrin was refined at 2. 07-A resolution with a final crystallographic R value of 15.8% (Rfree = 21.1%). The root mean square deviation in the position of C-alpha atoms between this recombinant enzyme and the native enzyme was 0.22 A. These results indicate that the expression system established here is suitable for studying structure-function relationships of beta-amylase. The conformation of the bound beta-cyclodextrin takes an ellipsoid shape in contrast to the circular shape of the bound alpha-cyclodextrin. The cyclodextrins shared mainly two glucose binding sites, 3 and 4. The glucose residue 4 was slightly shifted from the maltose binding site. This suggests that the binding site of the cyclodextrins is important for its holding of a cleaved substrate, which enables the multiple attack mechanism of beta-amylase.

PubMed: 9677422
DOI: 10.1074/jbc.273.31.19859

Experimental method

X-RAY DIFFRACTION (2.07 Å)