Chen W, Liu L, Sun P, Jin C
Laboratory of Enzymology Institute of Microbiology, Chinese Academy of Science, Beijing 100080.
Wei Sheng Wu Xue Bao. 2000 Feb;40(1):57-61.
2.2 kb DNA fragment encoding a novel enzyme, maltooligosyl trehalose synthase (MTSase) was amplified from Sulfolobus shibatae by using PCR technique. The amplified 2.2 kb DNA fragment was inserted into an expression vector, pBV220, to yield the recombinant plasmid pSBGT1. MTSase gene in pBSGT1 was expressed in E. coli. The molecular weight of expressed MTSase detected by SDS-PAGE was about 74 kD, which is conformed with that deduced from nucleotide sequence. The expressed MTSase protein accounted for about 4.4% of the total cell protein. The MTSase from transformants containing pBSGT1 is capable of decreasing DE value, forming non-reducing or less-reducing saccharides when allowed to act on reducing partial starch hydrolysates.
利用PCR技术从嗜热栖热菌中扩增出编码一种新型酶——麦芽寡糖基海藻糖合酶（MTSase）的2.2 kb DNA片段。将扩增得到的2.2 kb DNA片段插入表达载体pBV220中，构建重组质粒pSBGT1。pSBGT1中的MTSase基因在大肠杆菌中表达。经SDS-PAGE检测，表达的MTSase分子量约为74 kD，与核苷酸序列推导的结果相符。表达的MTSase蛋白约占总细胞蛋白的4.4%。含有pSBGT1的转化体中的MTSase作用于部分淀粉水解还原产物时，能够降低DE值，形成非还原或低还原糖类。
