Characterization of chloramphenicol resistance in Lactobacillus plantarum caTC2

A strain of Lactobacillus plantarum caTC2R isolated from a meat source was resistant to chloramphenicol (30 mu g/ml). Resistance was mediated through an inducible chloramphenicol acetyltransferase. Plasmid analysis of this strain showed three plasmids, of which the 8.5-kb plasmid apparently encodes the gene for chloramphenicol resistance. This plasmid was lost at high frequency (25%) when the Lactobacillus was subcultured at a higher than optimal temperature (40 degree C).