NUCLEOTIDE-SEQUENCES FROM THE COLICIN-E5, COLICIN-E6 AND COLICIN-E9 OPERONS - PRESENCE OF A DEGENERATE TRANSPOSON-LIKE STRUCTURE IN THE COLE9-J PLASMID
NUCLEOTIDE-SEQUENCES FROM THE COLICIN-E5, COLICIN-E6 AND COLICIN-E9 OPERONS - PRESENCE OF A DEGENERATE TRANSPOSON-LIKE STRUCTURE IN THE COLE9-J PLASMID
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DOI：
10.1007/bf02464892
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发表时间：
1989-06-01
期刊：
影响因子：
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通讯作者：
CONDIE, JA
中科院分区：
文献类型：
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作者：
LAU, PCK;CONDIE, JA
测定了质粒ColE 5 -099的1288 bp、ColE 6-CT 14的1609 bp和ColE 9-J的2099 bp的核苷酸序列。这些序列包括大肠杆菌素E5、E6和E9的C-末端受体结合和核酸酶结构域的结构基因，它们的顺式或反式作用免疫蛋白和四种裂解蛋白，包括ColE 9-J质粒中存在的非脂蛋白性质的非典型裂解蛋白（Lys*）。ColE 6基因的组织，在顺序col-imm-E8 imm-lys，是相同的，在先前描述的双免疫基因系统的ColE 3- CA 38（RNA酶生产商）。两个质粒中相应基因的同源性为87%~ 94%。在ColE 9-J中，基因被组织为col-imm-lys* E5 imm-lys。E9 col-imm基因对与大肠杆菌素E2-P9型（DNA酶生产者）同源。E9 imm的下游是反式作用的E5 imm（命名为E5 imm [E9]）。E5 Imm [E9]的预测结构和ColE 5 -099质粒中的顺式作用Imm（相差一个氨基酸）均未显示出与已测序的其他免疫结构的任何相似性。此外，E5 col序列不同于先前预测的其他大肠杆菌素，除了保守的btuB特异性受体结合结构域。在ColE 9-J质粒中发现了一个新的205个核苷酸长的插入序列。这个插入序列，我们命名为ISE 9，具有以前在质粒pSC 101中发现的简并转座子IS 101的特征。ISE 9的一个作用是非典型裂解基因lys* 的存在。ColE 9质粒中转座子样元件的存在证实了与大肠杆菌素E质粒进化相关的新现象。
The nucleotide sequences of 1288 bp of plasmid ColE5-099, 1609 bp of ColE6-CT14 and 2099 bp of ColE9-J were determined. These sequences encompass the structural genes for the C-terminal receptor-binding and nuclease domains of colicins E5, E6 and E9, their cis- or trans-acting immunity proteins and four lysis proteins including an atypical one of non-lipoprotein natue (Lys*) present in the ColE9-J plasmid. The ColE6 gene organisation, in the order col-imm-E8imm-lys, is identical to that found in the previously described double-immunity gene system of ColE3- CA 38 (an RNase producer). The corresponding genes in the two plasmids are 87%-94% homologous. In ColE9-J, the genes are organised as col-imm-lys* E5imm-lys. The E9 col-imm gene pair is homologous to the colicin E2-P9 type (a DNase producer). Downstream from E9imm is an E5imm (designated E5imm[E9]) which is trans-acting. Neither the predicted structures of E5Imm[E9] nor the cis-acting Imm resident in the ColE5-099 plasmid which differs by a single amino acid shows any resemblance to other immunity structures which have been sequenced. Furthermore, the E5col sequences differ from those predicted previously for other colicins except for the conserved btuB-specified receptor-binding domain. A novel 205 nucleotide long insertion sequence is found in the ColE9-J plasmid. This insertion sequence, which we named ISE9, has features reminiscent of the degenerate transposon IS101 previously found in plasmid pSC101. One effect of ISE9 is the presence of the atypical lysis gene, lys*. The presence of a transposon-like element in the ColE9 plasmid exemplifies a new phenomenon relevant to the evolution of colicin E plasmids.