RP4 Fertility Variants inAcinetobacter calcoaceticus

Abstract
SUMMARY: The resistance plasmid RP4 can be used to mediate conjugation inAcinetobacter calcoaceticus. Transfer of chromosomal genes occurs only on solid surfaces and not in liquid matings. Two RP4-carrying donor strains which donate the chromosome in different directions from different origins have been isolated. As a result it is possible to demonstrate that the linkage map ofA. calcoaceticusis circular.The fate of RP4 in recombinants was examined. Although frequent loss of the complete plasmid was detected, segregation of plasmid antibiotic resistances was not observed.A possible mechanism by which RP4 could interact with theA. calcoaceticuschromosome is discussed.