阿卡波糖对还原型DP18-麦芽糖糊精和直链淀粉水解的抑制作用：动力学研究

Inhibition of reduced DP18-maltodextrin and amylose hydrolysis by acarbose: kinetic studies.

作者信息

Alkazaz M, Desseaux V, Prodanov E, Marchis-Mouren G, Santimone M

机构信息

Laboratoire de Biochimie et Biologie de la Nutrition URA-CNRS 1820, Faculté des Sciences et Techniques de St Jérôme, Université d'Aix-Marseille III, France.

出版信息

Int J Biol Macromol. 1997 Aug;21(1-2):97-101. doi: 10.1016/s0141-8130(97)00047-0.

DOI:10.1016/s0141-8130(97)00047-0

PMID:9283022

Abstract

Kinetics of inhibition of porcine pancreatic alpha-amylase by acarbose were performed using maltodextrin and amylose as substrates. Similar Lineweaver-Burk primary plots were obtained. Two mixed non-competitive models are proposed. X-ray crystallographic data (Qian, M., Buisson, G., Duée, E., Haser, R. and Payan, F. Biochemistry, 1994; 33: 6284-6294) are in support of the mixed non-competitive inhibition model which involves abortive complexes. Secondary plots are different indicating that in the maltodextrin hydrolysis, one molecule of acarbose is bound per amylase molecule, while using amylose as substrate two molecules of acarbose are bound. These two kinetically determined binding sites might correspond to the two surface sites shown by X-ray crystallography (Qian, M., Haser, R. and Payan, F. Protein Science 1995; 4: 747-755).

摘要

以麦芽糊精和直链淀粉为底物，研究了阿卡波糖对猪胰α-淀粉酶的抑制动力学。得到了相似的Lineweaver-Burk原始图。提出了两种混合型非竞争性模型。X射线晶体学数据（钱，M.，比松，G.，迪厄，E.，哈泽尔，R.和帕扬，F.《生物化学》，1994年；33: 6284 - 6294）支持涉及无效复合物的混合型非竞争性抑制模型。二级图不同，表明在麦芽糊精水解过程中，每个淀粉酶分子结合一个阿卡波糖分子，而以直链淀粉为底物时，结合两个阿卡波糖分子。这两个通过动力学确定的结合位点可能对应于X射线晶体学显示的两个表面位点（钱，M.，哈泽尔，R.和帕扬，F.《蛋白质科学》，1995年；4: 747 - 755）。