Schizosaccharomyces pombe produces novel Gal0-2Man1-3 O-linked oligosaccharides.
Schizosaccharomyces pombe produces novel Gal0-2Man1-3 O-linked oligosaccharides.
复制标题
粟酒裂殖酵母产生新型 Gal0-2Man1-3 O-连接寡糖。
DOI：
10.1093/glycob/9.5.507
复制
发表时间：
1999
期刊：
影响因子：
4.3
通讯作者：
Trimble,RB
中科院分区：
文献类型：
--
作者：
Gemmill,TR;Trimble,RB
通过内切-β- n -乙酰氨基葡萄糖苷酶H和肽- n4 -天冬酰胺酰胺水解酶F的顺序处理，分裂糖菌的全细胞糖蛋白被β-消除，以0.1 M NaOH/1 M nabh4释放o-连接的低聚糖。采用凝胶排斥色谱法将糖醛醇分离成大小从Hexitol到Hex4Hexitol的池。对己醇池的分析表明，Man是唯一与丝氨酸或苏氨酸残基相连的糖。Hex1Hexitol池包含gal α 1,2man -ol （2A）和man α 1,2man -ol （2B）两种成分。Hex2Hexitol池包含两种成分：Galα1,2Manα1,2Man-ol （3A）和Manα1,2Manα1,2Man-ol （3B）。两种Hex3Hexitol成分分别为α α1,2(gal α1,3) - α1,2 - man -ol （4A）和α α1,2(gal α1,3) - man - 1,2 - man -ol （4B）。Hex4Hexitol组分为单一同分异构体，由gal α1,2(gal α1,3) - α 1,2man - α 1,2man -ol （5AB）组成。令人惊讶的是，在这些低聚糖中没有检测到半乳糖糖。Thegma12 (T。G. Chappell和G. Warren(1989) .细胞生物学。[j] .中国生物医学工程学报，2009,26(2):393 - 397。α1,2-半乳糖转移酶缺陷突变体和gma12/gth1双突变体。庞贝菌株也进行了类似的研究。结果表明，gma12p仅负责化合物2A中末端α1,2-linked Gal的添加，而4A中α1,2-linked Gal的添加则需要gma12p和gth1p中的一个或两个。这两种转移酶在很大程度上负责同分异构体5AB的末端Gal。通过1h NMR波谱测定，两者对大n链半乳甘露聚糖的结构都没有任何明显的影响。因此，虽然gth1p和gma12p似乎负责将α1,2- Gal添加到末端Man上，但既没有将半乳糖侧链添加到n -连接的聚α1,6-Man外链上，也没有将o -连接的支链形成的α1,3- Gal添加到o -连接的聚糖中。此外，在o -连接的聚糖中存在hexα 1,2(galα 1,3)Manα1,2-结构，这意味着在s .pombe中存在一种新的支链形成的α1,3-半乳糖转移酶。
Schizosaccharomyces pombewhole-cell glycoproteins, previously depleted of N-linked glycans by sequential treatment with endo-β-N-acetylglucosaminidase H and peptide-N4-asparagine amidohydrolase F, were β-eliminated with 0.1 M NaOH/1 M NaBH4to release the O-linked oligosaccharides. The saccharide-alditols were separated by gel-exclusion chromatography into pools from Hexitol to Hex4Hexitol in size. Analysis of the Hexitol pool indicated Man to be the only sugar linked to Ser or Thr residues. The Hex1Hexitol pool contained two components, Galα1,2Man-ol (2A) and Manα1,2Man-ol (2B). The Hex2Hexitol pool contained two components, Galα1,2Manα1,2Man-ol (3A) and Manα1,2Manα1,2Man-ol (3B). The two Hex3Hexitol components were Galα1,2(Galα1,3)Manα1,2Man-ol (4A) and Manα1,2(Galα1,3)Manα1,2Man-ol (4B). The Hex4Hexitol component was found to be a single isomer with the composition of Galα1,2(Galα1,3)Manα1,2Manα1,2Man-ol (5AB). Surprisingly, galactobiose was not detected in any of these oligosaccharides. Thegma12(T. G. Chappell and G. Warren (1989) J. Cell Biol., 109, 2693–2707) andgth1(T. G. Chappell personal communication) α1,2-galactosyltransferase-deficient mutants and thegma12/gth1double mutantS.pombestrains were similarly examined. The results indicated that gma12p is solely responsible for the addition of terminal α1,2-linked Gal in compound 2A, while one or both of gma12p and gth1p are required for the α1,2-linked Gal in 4A. Both transferases are largely responsible for terminal Gal in isomer 5AB. Neithergma12norgth1had any discernible effect on the structure of the large N-linked galactomannans as determined by1H NMR spectroscopy. Thus, while gth1p and gma12p appear responsible for adding α1,2-linked Gal to terminal Man, neither adds galactose side chains to the N-linked poly α1,6-Man outerchain, nor the O-linked branch-forming α1,3-linked Gal. Furthermore, the presence of Hexα1,2(Galα1,3)Manα1,2- structures in the O-linked glycans implies the presence of a novel branch-forming α1,3-galactosyltransferase inS.pombe.