小麦高分子量谷蛋白亚基一级结构分析

Analysis of the Primary Structure of High Molecular Weight Glutenin Subunits in Wheat

为从一级结构水平揭示小麦高分子量麦谷蛋白亚基的结构、功能及其进化上的关系,利用生物信息学软件(DNAMAN)对已在GenBank数据库中登录的22个小麦高分子量麦谷蛋白亚基序列进行了分析。结果表明,这些高分子量谷蛋白亚基平均含氮量为16.186%;其各种氨基酸含量基本恒定,其中谷氨酰胺含量最高(33.74%),且主要以QQ形式连接在一起,这种结构特点可能影响小麦面粉的加工品质;同时在一级结构序列上还发现有232个保守的氨基酸位点(56个单个氨基酸座位和一些长短不同的氨基酸片段),较大的保守性氨基酸片段主要为AEGEAS-QLQCER/HEL,GSFY PG/SETTP-QQLQQ,YYPGQAS/FP/SQQ/RP/SGQG/RQQ,PGQGQQ/PG/A/YYPTS-QQ等;分别有6组共13个序列相似度均达到100%,推测这些高分子量谷蛋白亚基在进化上具有较强的保守性。

in order to uncover the relationship among the structure, function, and evolution in different high molecular weight glutenin subunits （HMW GS） of wheat on the level of primary structure, the amino acid sequence of 22 high molecular weight glutenin subunits submitted to GenBank database were analyzed by means of a bioinformatics software （DNAMAN）. The results showed that the average nitrogen content was 16. 186% in HMW GS and the contents of different amino acid were constant among all the analyzed subunits and QQ. This structure character might the highest was Q （33.74%）. affect the processing quality of it appeared mainly in the form of wheat flour. There also were 282 conserved amino acid situs （56 conserved single amino acid situs and some different short conserved segments） found in the primary structure. The longer conserved segments were AEGEAS-QLQCER/ HEL, GSFY PG/SETTP-QQLQQ, YYPGQAS/FP/SQQ/RP/SGQG/ RQQ, PGQGQQ/PG/A/ YYPTS QQ. There were six groups including thirteen sequences with 100% similarity and this implied that they might be highly conservation in evolution.