Transformation in restriction-deficient Salmonella typhimurium LT2.

Stable restriction-deficient, modification-proficient galE (JR501) and F'galE+ (JR502) strains of Salmonella typhimurium were constructed and the effects of restriction on transformation by plasmid pBR322 were tested. Several factors which affect transformation efficiency were systematically examined to determine optimum transformation conditions and a simplified method is presented.