Sivov I G, Bol'shakova T N, Karataev G I
Gamaleya Institute for Epidemiology and Microbiology, Russian Academy of Medical Sciences, Moscow, 123098 Russia.
Genetika. 2001 Jul;37(7):900-7.
Integration of a plasmid carrying the TnBP3 transposon of Bordetella pertussis into the chromosome of Escherichia coli and transpositions of the integrated structure within a chromosome in the wild-type and mutant cells ptsH devoid of the major Hpr protein of the phosphoenolpyruvate-dependent phosphotransferase system were studied. When transposed to a new chromosome site, the integrated structure was precisely (or almost precisely) excised from the metY gene sequence, which resulted in restoration of the Met+ phenotype. The integration and transposition events were only observed in the E. coli cells carrying the ptsH+ allele. The ptsH mutations inhibited integration and intramolecular transposition, which were restored after phenotypic or genetic suppression of the ptsH mutation. The intensity of the processes studied were suggested to depend on the integrity of a chain that ensures transferring of the phosphoryl residue by proteins of the phosphotransferase system in E. coli K12. The results obtained indicate that the ptsH mutants of E. coli can serve as the optimal host for cloning of fragments carrying repeated sequences of B. pertussis, which may apply to the repeated sequences of other microorganisms.
研究了携带百日咳博德特氏菌TnBP3转座子的质粒整合到大肠杆菌染色体中，以及在野生型和缺乏磷酸烯醇丙酮酸依赖性磷酸转移酶系统主要Hpr蛋白的ptsH突变细胞的染色体内整合结构的转座情况。当整合结构转座到新的染色体位点时，它从metY基因序列中被精确（或几乎精确）切除，这导致Met+表型的恢复。整合和转座事件仅在携带ptsH+等位基因的大肠杆菌细胞中观察到。ptsH突变抑制了整合和分子内转座，在ptsH突变的表型或遗传抑制后恢复。研究过程的强度被认为取决于确保磷酸转移酶系统的蛋白质在大肠杆菌K12中转移磷酰基残基的链的完整性。获得的结果表明，大肠杆菌的ptsH突变体可作为克隆携带百日咳博德特氏菌重复序列片段的最佳宿主，这可能适用于其他微生物的重复序列。
