Abstract
The chloramphenicol-inducible regulation of the expression of cat genes from two Gram-positive bacteria, Staphylococcus aureus and Bacillus pumilus has been suggested to result from the presence of inverted repeat sequences that span the ribosome-binding site (RBS) for cat. In support this hypothesis, we demonstrate that two derivatives of the pC194 cat gene which are constitutively expressed in Bacillus subtilis are deleted for all or a major portion of the inverted-repeat sequences.