Capacity of Aquatic Bacteria to Act as Recipients for Plasmid DNA

摘要

Sixty-nine randomly selected, gram negative, freshwater bacterial isolates were screened for their ability to receive and express plasmids from Pseudomonas aeruginosa donors, using a plate mating technique. The plate mating technique identified 26 of the isolates as recipient-active for the self-transmissible, wide host-range plasmid R68, 14% were recipient-active, by RP4 mobilization, for the wide host-range plasmid cloning vector R1162. Frequencies of transfer were compared by using 3 conjugal transfer procedures: broth mating, plate mating, and filter mating. With every recipient tested a solid environment was superior to liquid for transfer. The broth mating technique failed to demonstrate R68 transfer in 63% of the recipient-active isolates. Filter mating, in general, yielded the highest transfer frequencies. The more rapid plate mating procedure, however, was just as sensitive for testing the capacity of natural isolates to participate in conjugal plasmid transfer. (Copyright (c) 1988, American Society for Microbiology.)