弗氏鼠白血病病毒糖蛋白中对β-N-乙酰葡糖胺内切酶H敏感的寡糖结构

Structure of the oligosaccharides sensitive to endo-beta-n-acetylglucosaminidase H in the glycoprotein of Friend murine leukemia virus.

作者信息

Geyer R, Geyer H, Egge H, Schott H H, Stirm S

出版信息

Eur J Biochem. 1984 Sep 17;143(3):531-9. doi: 10.1111/j.1432-1033.1984.tb08402.x.

DOI:10.1111/j.1432-1033.1984.tb08402.x

Abstract

The surface glycoprotein (mixture of isoglycoproteins with Mr 69 000 and 71 000) was isolated from the particles of Friend murine leukemia virus, and was successively digested with protease and with endo-beta-N-acetylglucosaminidase from Streptomyces griseus. Roughly 20% (w/w) of the carbohydrates in this glycoprotein were thus released, and they were fractionated by high-performance liquid chromatography after reduction with KB3H4/NaBH4. The radioactive oligosaccharitol fractions obtained were analyzed by exoglycosidase digestion, by acetolysis, and, after permethylation, by fast atom-bombardment mass spectrometry, as well as by capillary gas-liquid chromatography/mass spectrometry following hydrolysis, reduction and peracetylation. Around 85% (mol/mol) of the endo-H-sensitive viral glycans were thus found to be oligomannosidic oligosaccharitols of size classes Man5GlcNAcOH, Man6GlcNAcOH, Man8GlcNAcOH, Man7GlcNAcOH, and Man9GlcNAcOH (in order of prevalence), and the major structural isomers of each size class were identified. About another 15% (mol/mol) of the oligosaccharitols were shown to be of the 'mixed type', comprising mainly four species in which the Man(alpha 1----6)-branch of the Man alpha 1----6 (Man alpha 1----3) Man beta 1----4GlcNAcOH core is substituted by one or two additional alpha-mannoses, while the Man(alpha 1----3)-branch carries an N-acetyllactosamine unit substituted by sialic acid, or by Gal(alpha 1----3).

摘要

从弗氏鼠白血病病毒颗粒中分离出表面糖蛋白（分子量为69000和71000的异糖蛋白混合物），先后用蛋白酶和来自灰色链霉菌的内切β-N-乙酰氨基葡萄糖苷酶进行消化。该糖蛋白中约20%（w/w）的碳水化合物由此释放出来，在用KB3H4/NaBH4还原后，通过高效液相色谱法进行分级分离。对得到的放射性低聚糖醇馏分进行外切糖苷酶消化、乙酰解分析，在全甲基化后，通过快原子轰击质谱分析，以及在水解、还原和全乙酰化后通过毛细管气-液色谱/质谱分析。结果发现，约85%（mol/mol）对内切糖苷酶H敏感的病毒聚糖是大小类别为Man5GlcNAcOH、Man6GlcNAcOH、Man8GlcNAcOH、Man7GlcNAcOH和Man9GlcNAcOH（按丰度顺序）的寡甘露糖型低聚糖醇，并鉴定了每个大小类别的主要结构异构体。另外约15%（mol/mol）的低聚糖醇显示为“混合型”，主要包括四种类型，其中Manα1----6（Manα1----3）Manβ1----4GlcNAcOH核心的Man（α1----6）分支被一个或两个额外的α-甘露糖取代，而Man（α1----3）分支带有一个被唾液酸或Gal（α1----3）取代的N-乙酰乳糖胺单元。