Chloramphenicol Acetyltransferases Specified by fi R Factors

Abstract
Chloramphenicol acetyltransferases specified by fi (F fertility-noninhibiting) R factors were compared with those specified by the fi + R factors R1, 222, and R6-S. Three classes of enzyme were distinguished: class I was determined by group N fi R factors and was indistinguishable from the enzyme determined by fi + R factors, class II was correlated with group W fi R factors, and class III was determined by R387, an unclassified fi R factor.