【摘要】 利用生物信息学手段 ,在GenBank中进行氨基酸序列的同源性比较分析 ,检索到来自于耐放射异常球菌(Deinococcusradiodurans)基因组序列中一功能未确定的开放阅读框 (ORF) ,其氨基酸序列和已报道的海藻糖合成酶的氨基酸序列有约 6 0 %的同源性 .将这段ORF克隆到大肠杆菌进行表达 ,并进行功能鉴定 .实验表明这段ORF序列所编码的是一种海藻糖合成酶 ,它能将麦芽糖分子转化成海藻糖分子 ,以 30 %的麦芽糖为底物时能将约 6 5 %的麦芽糖转化成海藻糖 .重组酶性质初步研究表明 ,在 pH 7 0 ,最佳温度 30℃转化麦芽糖效率 最高 .更多还原

【Abstract】 An open reading frame (ORF) was annotated as putative trehalose synthase in Deinococcus radiodurans sequenced genome, which has been found in GenBank database through amino homology blast base on combination of bioinformatics. Blasting against the database indicates that amino acid sequence of this ORF has less than 60% homology with the reported terhalose synthases. The function, which was identified by expressing this ORF in Escherichia coli, proves this ORF is a novel trehalose synthase gene. Using the 30% maltose as substrate, about 65% maltose can be converted into trehalose by this enzyme. Recombinant enzyme showed optimal activity at pH 7.0 and 30℃ when it converts maltose into trehalose.更多还原