Salmonella typhimurium LT2 strains which are r- m+ for all three chromosomally located systems of DNA restriction and modification.
نویسندگان
چکیده
We describe the derivation of two strains of Salmonella typhimurium LT2 which are r- m+ for all three of the known chromosomal genes for the restriction and modification of DNA, hsdLT, hsdSA, and hsdSB; the strains were designated LB5000 and LB5010. LB5000 is a smooth derivative sensitive to phage P22; LB5010 is a galE strain sensitive to phage P1.
منابع مشابه
Three Chromosomally Located Systems of DNA Restriction and Modification
Since the role of DNA restriction-modification (R-M) systems of hsd genes has been elucidated, recipient cells for unmodified or foreign DNA are usually restrictionless mutants. Such mutants may either modify and have the phenotype rm+ or fail to modify and have the phenotype rm-. Each R-M system consists of three genes: hsdS for specificity, hsdR for restriction, and hsdM for modification (1)....
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ورودعنوان ژورنال:
- Journal of bacteriology
دوره 156 1 شماره
صفحات -
تاریخ انتشار 1983