Lanka E, Lurz R, Kröger M, Fürste J P
Mol Gen Genet. 1984;194(1-2):65-72. doi: 10.1007/BF00383499.
The pri gene locus of the conjugative broad host range plasmid RP4 maps between coordinates 40.3 and 43.5 and encodes two antigenically related forms of a DNA primase with a molecular mass of 118 and 80 kDa (kilodalton). Genesis of these two products has been examined using Pri+-recombinant plasmids. As shown by deletion analysis, the primase polypeptides are tow separate translation products which arise from an in-phase overlapping gene arrangement. It is suggested that transcription of a set of RP4 genes including the pri gene starts at a promoter site within the Tra1 region. In vivo, RP4 mutant primase can apparently substitute for Escherichia coli primase as demonstrated by measuring suppression of the dnaG3 (ts) mutant.
接合型广宿主范围质粒RP4的pri基因座定位于坐标40.3和43.5之间，编码两种抗原相关形式的DNA引发酶，分子量分别为118 kDa（千道尔顿）和80 kDa。已使用Pri⁺重组质粒研究了这两种产物的起源。缺失分析表明，引发酶多肽是两个独立的翻译产物，它们源自同相重叠基因排列。有人提出，包括pri基因在内的一组RP4基因的转录起始于Tra1区域内的一个启动子位点。在体内，通过测量对dnaG3（ts）突变体的抑制作用表明，RP4突变引发酶显然可以替代大肠杆菌引发酶。
