间隔基修饰的、光不稳定的四糖作为麦芽五糖的类似物，是用于猪胰腺α-淀粉酶的通用探针。

Spacer-modified, photolabile tetrasaccharides as analogues of maltopentaose are versatile probes for porcine pancreatic alpha-amylase.

作者信息

Lehmann J, Ziser L

机构信息

Institut für Organische Chemie und Biochemie, Universität Freiburg, F.R.G.

出版信息

Carbohydr Res. 1992 Feb 17;225(1):83-97. doi: 10.1016/0008-6215(92)80041-x.

DOI:10.1016/0008-6215(92)80041-x

PMID:1633607

Abstract

The syntheses are described of methyl 4'-O-[4-S-(3-azi-4-alpha-D-glucopyranosyloxybutyl)-6-deoxy-4 -thio-alpha-D-xylo-hex-5-enopyranosyl]-alpha-maltoside (28), methyl 4-O-[4-S-(3-azi-4-alpha-maltosyloxybutyl)-6-deoxy-4-thio- alpha-D-xylo-hex-5-enopyranosyl]-alpha-D-glucopyranoside (29), and methyl 4-S-(3-azi-4-alpha-maltotriosyloxybutyl)-6-deoxy-4-thio- alpha-D-xylo-hex-5-enopyranoside (30), which are analogues of maltopentaose in which a central glucosyl unit is replaced by an acyclic, four-membered hydrocarbon spacer carrying a photolabile azi group. Only 30 was slowly cleaved by high concentrations of pancreatic alpha-amylase. The Ki values (mM) were 0.15 (28), 2.1 (29), and 2.5 (30). Deactivation of the enzyme by irradiation in the presence severely of 28-30 was 96.4%, 98.1%, and 40%, respectively. There is an indication for regiospecific photoaffinity labelling of the binding subsites of the enzyme.

摘要

描述了4'-O-[4-S-(3-叠氮基-4-α-D-吡喃葡萄糖氧基丁基)-6-脱氧-4-硫代-α-D-木糖基-己-5-烯吡喃糖基]-α-麦芽糖苷甲酯（28）、4-O-[4-S-(3-叠氮基-4-α-麦芽糖氧基丁基)-6-脱氧-4-硫代-α-D-木糖基-己-5-烯吡喃糖基]-α-D-葡萄糖苷甲酯（29）和4-S-(3-叠氮基-4-α-麦芽三糖氧基丁基)-6-脱氧-4-硫代-α-D-木糖基-己-5-烯吡喃糖苷甲酯（30）的合成，它们是麦芽五糖的类似物，其中一个中心葡萄糖基单元被带有光不稳定叠氮基的无环四元烃间隔基取代。只有30在高浓度胰腺α-淀粉酶作用下缓慢裂解。其Ki值（mM）分别为0.15（28）、2.1（29）和2.5（30）。在28 - 30存在下通过照射使酶失活的程度分别为96.4%、98.1%和40%。有迹象表明该酶的结合亚位点存在区域特异性光亲和标记。