Lamark T, Kaasen I, Eshoo M W, Falkenberg P, McDougall J, Strøm A R
Norwegian College of Fishery Sciences, University of Tromsø.
Mol Microbiol. 1991 May;5(5):1049-64. doi: 10.1111/j.1365-2958.1991.tb01877.x.
The sequence was determined of 6493 nucleotides encompassing the bet genes of Escherichia coli which encode the osmoregulatory choline-glycine betaine pathway. Four open reading frames were identified: betA encoding choline dehydrogenase, a flavoprotein of 61.9kDa; betB encoding betaine aldehyde dehydrogenase (52.8kDa); betT encoding a proton-motive-force-driven, high-affinity transport system for choline (75.8kDa); and betl, capable of encoding a protein of 21.8kDa, implicated as a repressor involved in choline regulation of the bet genes. Identification of the genes was supported by subcloning, physical mapping of lambda placMu53 insertions, amino acid sequence similarity, or N-terminal amino acid sequencing. The bet genes are tightly spaced, with betT located upstream of, and transcribed divergently to, the tandemly linked betIBA genes.
测定了大肠杆菌中包含编码渗透调节胆碱 - 甘氨酸甜菜碱途径的bet基因的6493个核苷酸的序列。鉴定出四个开放阅读框：betA编码胆碱脱氢酶，一种61.9kDa的黄素蛋白；betB编码甜菜碱醛脱氢酶（52.8kDa）；betT编码一种由质子动力驱动的、对胆碱具有高亲和力的转运系统（75.8kDa）；以及betI，能够编码一种21.8kDa的蛋白质，被认为是参与bet基因胆碱调节的阻遏物。基因的鉴定通过亚克隆、λplacMu53插入的物理图谱分析、氨基酸序列相似性或N端氨基酸测序得到支持。bet基因紧密排列，betT位于串联连接的betIBA基因的上游，并与其转录方向相反。
