Bustos-Martinez J A, Gomez-Eichelmann M C
Departamento de Biologia Molecular, Universidad Nacional Autonoma de Mexico, Mexico City, D.F.
J Bacteriol. 1987 Nov;169(11):4946-9. doi: 10.1128/jb.169.11.4946-4949.1987.
The numbers of chromosomal copies of the insertion sequence IS1 in strains of Salmonella typhimurium (0 to 8 copies), Shigella sonnei (56 copies), and Shigella flexneri (41 copies) isolated in Mexico City, Mexico, were similar to those reported for these genera isolated in other countries. Of the 11 Shigella strains studied, all carried several small plasmids; however, in only one of these strains did a small plasmid contain IS1, IS1 recombination, cointegrate formation mediated by IS1 or by the IS1-flanked transposon Tn9, and transposition of Tn9 occurred at a higher frequency in S. typhimurium than in either Escherichia coli or S. sonnei strains. The frequencies of IS1 recombination in S. typhimurium strains containing either zero or eight copies of IS1 were similar.
在墨西哥城分离出的鼠伤寒沙门氏菌菌株（0至8个拷贝）、宋内志贺氏菌（56个拷贝）和福氏志贺氏菌（41个拷贝）中，插入序列IS1的染色体拷贝数与在其他国家分离出的这些菌属所报告的拷贝数相似。在所研究的11株志贺氏菌中，所有菌株都携带几种小质粒；然而，这些菌株中只有一株的小质粒含有IS1，IS1重组、由IS1或由IS1侧翼转座子Tn9介导的共整合体形成，以及Tn9的转座在鼠伤寒沙门氏菌中发生的频率高于大肠杆菌或宋内志贺氏菌菌株。含有零个或八个IS1拷贝的鼠伤寒沙门氏菌菌株中IS1重组的频率相似。
