日本血吸虫大陆株26kDa谷胱甘肽S┐转移酶编码区基因的克隆及序列测定

CLONING AND SEQUENCING OF THE 26-kDa CLUTATHIONE S TRANSFERASE OF CHINESE SCHISTOSOMA JAPONICUM

从日本血吸虫大陆株成虫分离总ＲＮＡ，逆转录合成ｃＤＮＡ第一链，根据菲律宾株２６ｋＤａ谷胱甘肽Ｓ－转移酶（ＧＳＴ）的ｃＤＮＡ序列，设计并合成引物，扩增出２６ｋＤａ的编码区基因，并克隆到ｐＢｌｕｅｓｃｒｉｐｔ质粒。初步酶切鉴定后，从两端对插入片段进行核苷酸序列测定。结果与菲律宾株比较，核苷酸同源性为９９．８％，仅第５８２位碱基不同，菲律宾株为Ａ，而大陆株为Ｇ。比较从ｃＤＮＡ推导出的氨基酸序列，两者１００％相同。测序结果也与曼氏血吸虫进行了比较。

Total RNA was isolated from adult worms of Chinese S.japonicum. The first strand of cDNA was synthesized by SuperScript reverse transcriptase.Encoding region gene of Chinese Sj26 GST was amplified from cDNA pool with the primers dsigned and synthesized according to nucleotide sequences of Philippine Sj26 cDNA.Recombinant DNA (pSj26) that contains a cDNA of Chinese Sj26 was constructed in pBluescript DNA.After restriction analysis,the sequences of insert in pSj26 was deduced by dideoxynucleotide sequencing with Version 2 0 Sequenase.Comparing the Chinese and Philipping S.japonicum ,the nucleotide sequences show 99 8% identity,in which only one base was found to be different,and amino acid sequences deduced from cDNAs of both strains show 100% identity.The nucleotide and deduced amino acid sequences of cDNA clones corresponding to 26-kDa GST of Chinese S.japonicum and S.mansoni were compared.