Sen K, Sikkema D J, Murphy T F
Department of Medicine, State University of New York at Buffalo 14215, USA.
Gene. 1996 Oct 31;178(1-2):75-81. doi: 10.1016/0378-1119(96)00338-1.
The tolQ, R, A and B genes have been isolated from the DNA of Haemophilus influenzae and sequenced. The deduced amino acid (aa) sequence of the H. influenzae TolQ, TolR, TolA and TolB show 67, 63, 41 and 62% identity with Escherichia coli TolQRAB proteins, respectively. These four proteins are involved in transport of colicins and phages across the cell envelope. The translational stop codon of TolB (the last gene in the cluster) is 23 bases upstream of the start codon of the P6 lipoprotein gene. Primer extension and Northern blot analysis revealed that the start of the P6 transcript is within the tolB gene. Nucleotide sequence (nt) analysis of the entire tolQRABP6 region shows a transcriptional terminator immediately downstream of the P6 gene. The tolQRABP6 gene cluster of H. influenzae may thus constitute an operon.
已从流感嗜血杆菌的DNA中分离出tolQ、R、A和B基因并进行了测序。流感嗜血杆菌TolQ、TolR、TolA和TolB的推导氨基酸（aa）序列与大肠杆菌TolQRAB蛋白的同一性分别为67%、63%、41%和62%。这四种蛋白质参与大肠杆菌素和噬菌体跨细胞膜的转运。TolB（该基因簇中的最后一个基因）的翻译终止密码子位于P6脂蛋白基因起始密码子上游23个碱基处。引物延伸和Northern印迹分析表明，P6转录本的起始位置在tolB基因内。对整个tolQRABP6区域的核苷酸序列（nt）分析显示，P6基因下游紧邻一个转录终止子。因此，流感嗜血杆菌的tolQRABP6基因簇可能构成一个操纵子。
