1B2Y

STRUCTURE OF HUMAN PANCREATIC ALPHA-AMYLASE IN COMPLEX WITH THE CARBOHYDRATE INHIBITOR ACARBOSE

Summary for 1B2Y

• Entry DOI: 10.2210/pdb1b2y/pdb
• Descriptor: Pancreatic alpha-amylase, alpha-D-quinovopyranose-(1-4)-alpha-D-glucopyranose-(1-4)-4,6-dideoxy-4-{[(1S,4R,5S,6S)-4,5,6-trihydroxy-3-(hydroxymethyl)cyclohex-2-en-1-yl]amino}-alpha-D-glucopyranose-(1-4)-beta-D-glucopyranose, CHLORIDE ION, ... (5 entities in total)
• Functional Keywords: human alpha-amylase, acarbose, hydrolase
• Biological source: Homo sapiens (human)
• Cellular location: Secreted, extracellular space: P04746
• Total number of polymer chains: 1
• Total formula weight: 56798.58

Authors

Nahoum, V.,Payan, F. (deposition date: 1998-12-03, release date: 2000-02-16, Last modification date: 2024-11-06)

Primary citation

Nahoum, V.,Roux, G.,Anton, V.,Rouge, P.,Puigserver, A.,Bischoff, H.,Henrissat, B.,Payan, F.
Crystal structures of human pancreatic alpha-amylase in complex with carbohydrate and proteinaceous inhibitors.
Biochem.J., 346 Pt 1:201-208, 2000

PubMed Abstract: Crystal structures of human pancreatic alpha-amylase (HPA) in complex with naturally occurring inhibitors have been solved. The tetrasaccharide acarbose and a pseudo-pentasaccharide of the trestatin family produced identical continuous electron densities corresponding to a pentasaccharide species, spanning the -3 to +2 subsites of the enzyme, presumably resulting from transglycosylation. Binding of the acarviosine core linked to a glucose residue at subsites -1 to +2 appears to be a critical part of the interaction process between alpha-amylases and trestatin-derived inhibitors. Two crystal forms, obtained at different values of pH, for the complex of HPA with the protein inhibitor from Phaseolus vulgaris (alpha-amylase inhibitor) have been solved. The flexible loop typical of the mammalian alpha-amylases was shown to exist in two different conformations, suggesting that loop closure is pH-sensitive. Structural information is provided for the important inhibitor residue, Arg-74, which has not been observed previously in structural analyses.

PubMed: 10657258
DOI: 10.1042/0264-6021:3460201

Experimental method

X-RAY DIFFRACTION (3.2 Å)