Oppenheimer C L, Hill R L
J Biol Chem. 1981 Jan 25;256(2):799-804.
An alpha 1 goes to 3 mannoside beta 1 goes to 2 N-acetylglucosaminyltransferase has been purified 7000-fold in 36% yield from a Triton X-100 extract of rabbit liver acetone powder by affinity chromatography on UDP-hexanolamine agarose. Sodium dodecyl sulfate gel electrophoresis of the purified enzyme revealed two major bands with molecular weights of 58,000 and 46,000. Examination of the acceptor substrate specificity with pure oligomannosides revealed that the best acceptor had the following structure, (Formula: see text) and gave a single product in which N-acetylglucosamine was present in the sequence GlcNAc beta 1 goes to 2Man alpha 1 goes to 3Man beta 1 goes to 4 GlcNAc. Other terminal mannose residues in the best acceptor as well as that linked alpha 1 goes to 6 in the following oligosaccharide, (Formula: see text) were not acceptors. This specificity is in accord with the role of the transferase in the processing of mannose-containing oligosaccharides during glycoprotein biosynthesis.
一种α1→3甘露糖苷β1→2 N - 乙酰葡糖胺基转移酶已通过UDP - 己醇胺琼脂糖亲和层析从兔肝丙酮粉的Triton X - 100提取物中纯化了7000倍，产率为36%。纯化酶的十二烷基硫酸钠凝胶电泳显示出两条主要条带，分子量分别为58,000和46,000。用纯寡甘露糖检查受体底物特异性发现，最佳受体具有以下结构，（化学式：见正文）并产生单一产物，其中N - 乙酰葡糖胺存在于GlcNAcβ1→2Manα1→3Manβ1→4 GlcNAc序列中。最佳受体中的其他末端甘露糖残基以及以下寡糖中以α1→6连接的那个（化学式：见正文）不是受体。这种特异性与转移酶在糖蛋白生物合成过程中含甘露糖寡糖加工中的作用一致。
