Dorrington R A, Rawlings D E
Department of Microbiology, University of Cape Town, Rondebosch, South Africa.
J Bacteriol. 1990 Oct;172(10):5697-705. doi: 10.1128/jb.172.10.5697-5705.1990.
The nucleotide sequence of a 3,202-base-pair fragment which contained the minimum region required for replication of the broad-host-range plasmid, pTF-FC2, has been determined. At least five open reading frames and a region that affected the host range were identified. Proteins corresponding in size and location to four of the five open reading frames were produced in an in vitro transcription-translation system. The predicted amino acid sequences of two of the proteins were aligned with those of the RepA and RepC proteins of the broad-host-range IncQ plasmid RSF1010 and found to be 43 and 60% homologous, respectively. Despite this similarity, neither the RepA nor the RepC protein of the IncQ plasmid was able to complement mutations in the pTF-FC2 repA and repC genes. Although there was a considerable amount of DNA homology between pTF-FC2 and RSF1010 in the oriV region and the region coding for the RepA and RepC proteins, no other homology between the two plasmids at either the DNA or protein level could be detected.
已确定一个3202个碱基对片段的核苷酸序列，该片段包含广宿主范围质粒pTF-FC2复制所需的最小区域。鉴定出至少五个开放阅读框和一个影响宿主范围的区域。在体外转录-翻译系统中产生了与五个开放阅读框中的四个在大小和位置上相对应的蛋白质。其中两种蛋白质的预测氨基酸序列与广宿主范围IncQ质粒RSF1010的RepA和RepC蛋白质的序列比对，发现同源性分别为43%和60%。尽管有这种相似性，但IncQ质粒的RepA和RepC蛋白均不能互补pTF-FC2 repA和repC基因中的突变。虽然pTF-FC2与RSF1010在oriV区域以及编码RepA和RepC蛋白的区域存在大量DNA同源性，但在DNA或蛋白质水平上未检测到这两种质粒之间的其他同源性。
