Chromosomal location of a mutation causing chloramphenicol resistance inEscherichia coliK 12

Abstract

A chloramphenicol-resistant mutation inEscherichia coliK 12,cmlA1(previously designated1a), giving a higher Cm-resistance than other mutations yet examined, has been shown to have a chromosomal location, the gene order beinggal, λ,bio,cmlA,pyrD. CmlAcan be transduced efficiently into cm-sensitive strains by P1 with little phenotypic lag, and is co-transduced with the λ-attachment site (frequency 1·13%) but not withgalorpyrD.