RP4-mediated conjugation in Acinetobacter calcoaceticus.

The P class R factor RP4 was transferred from Escherichia coli K12 to Acinetobacter calcoaceticus. RP4 conferred similar levels of antibiotic resistance in A. calcoaceticus to those in the E. coli K12 donor. Only slight instability of RP4 in A. calcoaceticus was detected. Transfer of RP4 between strains of A. calcoaceticus was by conjugation and was accompanied by transfer of chromosomal genes. Possible polarity of marker transfer was observed and linkage between a number of chromosomal markers was demonstrated.