Properties of H^+-ATPase and cloning of its gene from ruminal bacteria

克隆了瘤胃细菌白瘤胃球菌（Ruminococcus albus）和牛链球菌（Streptococcus bovis）的H^+-ATP酶基因，并利用反向PCR方法测定了其操纵子（atp）的全序列。牛链球菌atp操纵子大小约为6.5 kbp，由atp E（c亚基）、B（a）、F（B）、H（delta）、A（alpha）、G（gamma）、D（beta）和C（beta）依次组成。在白纹伊蚊的atp操纵子中，atp E和B的顺序颠倒了，并假定atp I（i）也包含在内。牛链球菌atp操纵子的开放阅读框约为7 kbp，引物延伸分析结果表明，在pH4.7和pH7.0的牛链球菌细胞中，atp操纵子存在3种不同的atp-mRNA，每种mRNA的比例不同。这表明H^+-ATP酶的合成在转录或转录后水平受到调控。

A gene encoding H^+-ATPase of ruminal bacteria, Ruminococcus albus and Streptococcus bovis, was cloned and the entire operon (atp) was sequenced by the inverse PCR method. The atp operon of S.bovis was found to be approximately 6.5 kbp, which consisted of atp E (c-subunit), B (a), F (b), H (delta), A (alpha), G (gamma), D (beta), and C (epsilon) in this order. In the atp operon of R.albus, the order of atp E and B was inversed, and in addition assumed atp I (i) was included. The open reading frame was approximately 7 kbp.Primer extension analysis was conducted for the atp operon of S.bovis with the result indicating the presence of three different species of atp-mRNA.The proportion of each mRNA species was different in S.bovis cells grown at pH 4.7 compared to those grown at pH 7.0. This suggests that the synthesis of H^+-ATPase is regulated at the transcriptional or post-transcriptional level.