Inability of E. coli to transfer antibiotic resistance on meat surfaces

The surfaces of beef and chicken samples were inoculated with a mixture of a donor (resistant to tetracycline, streptomycin, chloramphenicol, ampicillin, neomycin and sulphonamide), and a recipient strain of Eschetichia coli. Meats were maintained at 20°C and 4°C and sampled daily. Transfer of antibiotic resistance could not be demonstrated at either temperature. The recipient strain survived without significant growth at 4°C, but failure to transfer antibiotic resistance at 20°C was considered to be due to the sessile growth of the organisms enclosed in a dense glycocalyx, precluding close contact between the organisms.