2DIJ

COMPLEX OF A Y195F MUTANT CGTASE FROM B. CIRCULANS STRAIN 251 COMPLEXED WITH A MALTONONAOSE INHIBITOR AT PH 9.8 OBTAINED AFTER SOAKING THE CRYSTAL WITH ACARBOSE AND MALTOHEXAOSE

Replaces:  1DIJ

Summary for 2DIJ

• Entry DOI: 10.2210/pdb2dij/pdb
• Related PRD ID: PRD_900001 PRD_900009 PRD_900030 PRD_900035
• Descriptor: CYCLODEXTRIN GLYCOSYLTRANSFERASE, alpha-D-glucopyranose-(1-4)-alpha-D-glucopyranose, alpha-D-glucopyranose-(1-4)-alpha-D-glucopyranose-(1-4)-alpha-D-glucopyranose, ... (9 entities in total)
• Functional Keywords: glycosyltransferase, transferase
• Biological source: Bacillus circulans
• Total number of polymer chains: 1
• Total formula weight: 77791.43

Authors

Strokopytov, B.V.,Knegtel, R.M.A.,Uitdehaag, J.C.M.,Dijkstra, B.W. (deposition date: 1998-05-27, release date: 1998-12-09, Last modification date: 2024-10-09)

Primary citation

Strokopytov, B.,Knegtel, R.M.,Penninga, D.,Rozeboom, H.J.,Kalk, K.H.,Dijkhuizen, L.,Dijkstra, B.W.
Structure of cyclodextrin glycosyltransferase complexed with a maltononaose inhibitor at 2.6 angstrom resolution. Implications for product specificity.
Biochemistry, 35:4241-4249, 1996

PubMed Abstract: Crystals of the Y195F mutant of cyclodextrin glycosyltransferase from Bacillus circulans strain 251 were subjected to a double soaking procedure, in which they were first soaked in a solution containing the inhibitor acarbose and subsequently in a solution containing maltohexaose. The refined structure of the resulting protein-carbohydrate complex has final crystallographic and free R-factors for data in the 8-2.6 angstrom resolution range of 15.0% and 21.5%, respectively, and reveals that a new inhibitor, composed of nine saccharide residues, is bound in the active site. The first four residues correspond to acarbose and occupy the same subsites near the catalytic residues as observed in the previously reported acarbose-enzyme complex [Strokopytov et al. (1995) Biochemistry 34, 2234-2240]. An oliogosaccharide consisting of five glucose residues has been coupled to the nonreducing end of acarbose. At the fifth residue the polysaccharide chain makes a sharp turn, allowing it to interact with residues Tyr89, Phe195, and Asn193 and a flexible loop formed by residues 145-148. On the basis of the refined model of the complex an explanation is given for the product specificity of CGTases.

PubMed: 8672460
DOI: 10.1021/bi952339h

Experimental method

X-RAY DIFFRACTION (2.6 Å)