[Isolation and characteristics of plasmids from Aeromonas]

Fourteen out of fifty-two examined strains of Aeromonas contain plasmids. One of them determines the resistance to tetracycline, streptomycin, and chloramphenicol. The pAs30 plasmid, 53 t. n. p. in size, is capable of conjugative transfer to bacteria of different genera, which permits us to consider it a broad host range plasmid. Using 12 restriction endonucleases, the physical map of the plasmid was plotted, on which the genes responsible for transporting functions and streptomycin resistance were tentatively located.