Tauch A, Zheng Z, Pühler A, Kalinowski J
Department of Genetics, University of Bielefeld, Germany.
Plasmid. 1998 Sep;40(2):126-39. doi: 10.1006/plas.1998.1362.
The clinical isolate Corynebacterium striatum M82B (formerly Corynebacterium xerosis M82B) carries the 50-kb R-plasmid pTP10 conferring resistance to the antibiotics chloramphenicol, erythromycin, kanamycin, and tetracycline. DNA sequence analysis of the chloramphenicol resistance region revealed the presence of the 4155-bp transposable element Tn5564. The ends of Tn5564 are identical 22-bp inverted repeats flanked by a 6-bp target site duplication. The central region of Tn5564 encodes the chloramphenicol resistance gene cmx, specifying a transmembrane chloramphenicol efflux protein, and an open reading frame homologous to transposases of insertion sequences identified in Arthrobacter nicotinovorans and Bordetella pertussis. Furthermore, the 1715-bp insertion sequence IS1513 encoding a putative transposase of the IS30 family is an integral part of Tn5564 and is located upstream of cmx. For transposon mutagenesis, Tn5564 was transferred to Corynebacterium glutamicum on a mobilizable Escherichia coli plasmid using RP4-mediated intergeneric conjugation. Transposition of Tn5564 in C. glutamicum occurred with a frequency of 3.3 x 10(-8) and resulted in an insertion into target sites containing the central palindromic tetranucleotide CTAG. A Tn5564-induced mutant strain of C. glutamicum was found to carry the transposon in the ftsZ gene region.
临床分离株纹带棒状杆菌M82B（以前称为干燥棒状杆菌M82B）携带50 kb的R质粒pTP10，赋予对氯霉素、红霉素、卡那霉素和四环素的抗性。氯霉素抗性区域的DNA序列分析揭示了4155 bp转座元件Tn5564的存在。Tn5564的末端是相同的22 bp反向重复序列，两侧是6 bp的靶位点重复序列。Tn5564的中央区域编码氯霉素抗性基因cmx，其指定一种跨膜氯霉素外排蛋白，以及一个与在嗜烟节杆菌和百日咳博德特氏菌中鉴定的插入序列转座酶同源的开放阅读框。此外，编码IS30家族推定转座酶的1715 bp插入序列IS1513是Tn5564的一个组成部分，位于cmx上游。为了进行转座子诱变，使用RP4介导的属间接合将Tn5564转移到可移动的大肠杆菌质粒上的谷氨酸棒状杆菌中。Tn5564在谷氨酸棒状杆菌中的转座频率为3.3×10^(-8)，并导致插入到含有中央回文四核苷酸CTAG的靶位点中。发现一株谷氨酸棒状杆菌的Tn5564诱导突变株在ftsZ基因区域携带转座子。
