1D3C

MICHAELIS COMPLEX OF BACILLUS CIRCULANS STRAIN 251 CYCLODEXTRIN GLYCOSYLTRANSFERASE WITH GAMMA-CYCLODEXTRIN

1D3C の概要

• エントリーDOI: 10.2210/pdb1d3c/pdb
• 関連するPDBエントリー: 1CDG 1CXF 1CXI 1CXK 1CXL 2DIJ
• 関連するBIRD辞書のPRD_ID: PRD_900001 PRD_900042
• 分子名称: CYCLODEXTRIN GLYCOSYLTRANSFERASE, alpha-D-glucopyranose-(1-4)-alpha-D-glucopyranose, Cyclooctakis-(1-4)-(alpha-D-glucopyranose), ... (6 entities in total)
• 機能のキーワード: alpha-amylase, product complex, oligosaccharide, family 13 glycosyl hydrolase, transglycosylation, induced fit, catalysis, transferase
• 由来する生物種: Bacillus circulans
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 79099.65

構造登録者

Uitdehaag, J.C.M.,Kalk, K.H.,van der Veen, B.A.,Dijkhuizen, L.,Dijkstra, B.W. (登録日: 1999-09-29, 公開日: 1999-12-22, 最終更新日: 2024-10-16)

主引用文献

Uitdehaag, J.C.,Kalk, K.H.,van Der Veen, B.A.,Dijkhuizen, L.,Dijkstra, B.W.
The cyclization mechanism of cyclodextrin glycosyltransferase (CGTase) as revealed by a gamma-cyclodextrin-CGTase complex at 1.8-A resolution.
J.Biol.Chem., 274:34868-34876, 1999

PubMed Abstract: The enzyme cyclodextrin glycosyltransferase is closely related to alpha-amylases but has the unique ability to produce cyclodextrins (circular alpha(1-->4)-linked glucoses) from starch. To characterize this specificity we determined a 1.8-A structure of an E257Q/D229N mutant cyclodextrin glycosyltransferase in complex with its product gamma-cyclodextrin, which reveals for the first time how cyclodextrin is competently bound. Across subsites -2, -1, and +1, the cyclodextrin ring binds in a twisted mode similar to linear sugars, giving rise to deformation of its circular symmetry. At subsites -3 and +2, the cyclodextrin binds in a manner different from linear sugars. Sequence comparisons and site-directed mutagenesis experiments support the conclusion that subsites -3 and +2 confer the cyclization activity in addition to subsite -6 and Tyr-195. On this basis, a role of the individual residues during the cyclization reaction cycle is proposed.

PubMed: 10574960
DOI: 10.1074/jbc.274.49.34868

実験手法

X-RAY DIFFRACTION (1.78 Å)