Alterations in host specificity of bacterial deoxyribonucleic acid after an increase in growth temperature of Pseudomonas aeruginosa.

Rolfe, B. (University of Melbourne, Victoria, Australia), and B. W. Holloway. Alterations in host specificity of bacterial deoxyribonucleic acid after an increase in growth temperature of Pseudomonas aeruginosa. J. Bacteriol. 92:43-48. 1966.-Increased recombination frequency is found with some crosses of Pseudomonas aeruginosa if the FP(-) parent is grown at 43 C prior to mating. This occurs where there is a difference in host specificity between the FP(-) and FP(+) parents, as is found in strains 1 and 2. Differences in recovery of unlinked markers are found in such crosses, and the results can be explained in terms of an alteration of the restriction and modification mechanisms by growth at the higher temperature, similar to that previously shown to occur with host-modified bacteriophage. As with that system, persistence of the temperature effect occurs for a number of generations after the strains are returned for growth at 37 C.