Liu S L, Hessel A, Sanderson K E
Department of Biological Sciences, University of Calgary, Alberta, Canada.
Mol Microbiol. 1993 Nov;10(3):655-64. doi: 10.1111/j.1365-2958.1993.tb00937.x.
We have established the genomic cleavage map of Salmonella enteritidis strain SSU7998 using pulsed-field gel electrophoresis. The chromosome of 4600 kb was analysed by XbaI (16 fragments), I-CeuI (7 fragments) and BlnI (12 fragments); the genome also contains a plasmid of 60 kb. Cleavage sites of I-Ceul, in the large subunit ribosomal RNA gene, are conserved from Salmonella typhimurium and Escherichia coli K-12, and the XbaI and BlnI sites in glt-tRNA are also conserved, but other sites are less conserved. Transposon Tn10, located at 60 different positions in the chromosome of S. typhimurium, was transduced by bacteriophage P22 into S. enteritidis and the insertion mapped using the XbaI and BlnI sites on Tn10. Gene order in S. enteritidis is identical to S. typhimurium LT2 and similar to E. coli K-12 except for an inversion of 815 kb, which covers the terminus region including T1 and T2. Endpoints are in the NDZs, or non-divisible zones, in which inversion endpoints were not detected in experiments in E. coli K-12 and S. typhimurium LT2. This inversion resembles the inversion between S. typhimurium and E. coli, but is longer at both ends.
我们利用脉冲场凝胶电泳建立了肠炎沙门氏菌菌株SSU7998的基因组切割图谱。通过XbaI（16个片段）、I-CeuI（7个片段）和BlnI（12个片段）对4600 kb的染色体进行了分析；该基因组还包含一个60 kb的质粒。I-Ceul在大亚基核糖体RNA基因中的切割位点在鼠伤寒沙门氏菌和大肠杆菌K-12中是保守的，glt-tRNA中的XbaI和BlnI位点也是保守的，但其他位点保守性较差。位于鼠伤寒沙门氏菌染色体60个不同位置的转座子Tn10被噬菌体P22转导到肠炎沙门氏菌中，并利用Tn10上的XbaI和BlnI位点对插入位置进行定位。肠炎沙门氏菌的基因顺序与鼠伤寒沙门氏菌LT2相同，与大肠杆菌K-12相似，只是有一个815 kb的倒位，该倒位覆盖了包括T1和T2在内的末端区域。倒位端点位于NDZ（或不可分割区域）中，在大肠杆菌K-12和鼠伤寒沙门氏菌LT2的实验中未检测到倒位端点。这种倒位类似于鼠伤寒沙门氏菌和大肠杆菌之间的倒位，但两端更长。
