Occurrence, transfer and mobilization in epilithic strains of Acinetobacter of mercury-resistance plasmids capable of transformation |
| |
Authors: | P A Rochelle M J Day J C Fry |
| |
Institution: | Department of Applied Biology, University of Wales Institute of Science and Technology, Cardiff, UK. |
| |
Abstract: | A 7.8 kb plasmid (pQM17) encoding mercury resistance was isolated from two epilithic strains of Acinetobacter calcoaceticus. The plasmid had a broad host range when mobilized by RP1, transferring into Pseudomonas aeruginosa, P. putida, P. fluorescens, Escherichia coli, Proteus vulgaris and Chromobacterium sp. with frequencies ranging from 5.3 x 10(-9) to 4.6 x 10(-4) per recipient. The plasmid could be transferred into A. calcoaceticus BD413 using intact cells of donor and recipient bacteria (i.e. natural transformation) and there was a broad temperature optimum (14-37 degrees C) for transformation. Transformation was as efficient in liquid matings as on plates but there was no effect of pH in the range 5.6-7.9. Maximum transformation frequencies were obtained after 24 h on agar plates containing 3.5-10 g C 1-1 with donor to recipient ratios ranging from 6 to 415. |
| |
Keywords: | |
|
|