Bahri S M, Ward J M
Biochemistry and Molecular Biology Department, University College London, UK.
Gene. 1993 May 15;127(1):133-7. doi: 10.1016/0378-1119(93)90628-g.
The alpha-amylase (Amy)-encoding gene (amy) of Streptomyces thermoviolaceus CUB74, previously cloned in Escherichia coli and S. lividans and localised on a 1.7-kb BamHI-SphI genomic DNA fragment, has been sequenced. A single open reading frame of 1380 bp, which could encode an Amy protein of 460 amino acids (aa), was identified. The deduced aa sequence of the thermophilic Amy is similar (up to 69.5%) to the mesophilic Amy of S. griseus, S. limosus, S. venezuelae and S. hygroscopicus. A 40% sequence similarity was found between the extracellular forms of the S. thermoviolaceus and the pig pancreatic Amy. In addition, the activity of the S. thermoviolaceus Amy is strongly inhibited by tendamistat, a potent inhibitor of mammalian Amy. The nucleotide sequence at the 5' end of amy was able to initiate transcription in S. lividans and contains a promoter whose sequence is identical to the promoters of the S. limosus, S. venezuelae and S. griseus amy.
嗜热紫链霉菌CUB74的α-淀粉酶（Amy）编码基因（amy），此前已克隆到大肠杆菌和变铅青链霉菌中，并定位在一个1.7kb的BamHI-SphI基因组DNA片段上，现已完成测序。鉴定出一个1380bp的单一开放阅读框，它可以编码一个由460个氨基酸（aa）组成的Amy蛋白。嗜热Amy推导的氨基酸序列与灰色链霉菌、栖土链霉菌、委内瑞拉链霉菌和吸水链霉菌的嗜温Amy相似（相似度高达69.5%）。在嗜热紫链霉菌的胞外形式与猪胰Amy之间发现了40%的序列相似性。此外，嗜热紫链霉菌Amy的活性受到腱糖胺的强烈抑制，腱糖胺是哺乳动物Amy的一种有效抑制剂。amy 5'端的核苷酸序列能够在变铅青链霉菌中启动转录，并且包含一个启动子，其序列与栖土链霉菌、委内瑞拉链霉菌和灰色链霉菌amy的启动子相同。
