Download MendeleyCrystal structures of human pancreatic alpha-amylase in complex with carbohydrate and proteinaceous inhibitors.
Nahoum, V., Roux, G., Anton, V., Rouge, P., Puigserver, A., Bischoff, H., Henrissat, B., Payan, F.(2000) Biochem J 346 Pt 1: 201-208
- PubMed: 10657258
- Primary Citation of Related Structures:
1B2Y - 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.
Organizational Affiliation:
Architecture et Fonction des Macromolécules Biologiques, CNRS-IFR1, 31 Chemin Joseph Aiguier, 13402 Marseille, France.
