Mutant of Salmonella typhimurium LT2 deficient in DNA adenine methylation.
نویسندگان
چکیده
A mutant of Salmonella typhimurium LT2 deficient in methylation of the adenine residues in the sequence 5'-GATC-3' was isolated. The mutation (dam-1) was linked to the cysG locus, and the properties of the mutant were similar to those of Escherichia coli dam mutants. Reversion of the hisC3076 frameshift marker by 9-aminoacridine was substantially enhanced by the dam-1 mutation, implying a direct role for adenine methylation in the prevention of frameshift mutation induction.
منابع مشابه
DNA adenine methylase mutants of Salmonella typhimurium show defects in protein secretion, cell invasion, and M cell cytotoxicity.
Mutants of Salmonella typhimurium lacking DNA adenine methylase are attenuated for virulence in BALB/c mice. LD(50) values of a DNA adenine methylation (Dam)(-) mutant are at least 10(3)- to 10(4)-fold higher than those of the parental strain when administrated by oral or intraperitoneal routes. Dam(-) mutants are unable to proliferate in target organs but persist in low numbers in these locati...
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ورودعنوان ژورنال:
- Journal of bacteriology
دوره 167 1 شماره
صفحات -
تاریخ انتشار 1986