The conjugation system determined by plasmid R477 and other plasmids belonging to the H2 incompatibility group
Cavazza, M.E.; Rodríguez Lemoine, V.
Revista Latinoamericana de Microbiologia 26(1): 61-68
1984
ISSN/ISBN: 0187-4640 PMID: 6148780 Document Number: 231839
The temperature-sensitive transfer system determined by plasmid R477 and other plasmids belonging to incompatibility group H2 was studied. Transfer depended on the growth temperature of the donor. Donor cells grown at 24.degree. C for many generations transferred at high frequency. Transfer ability was lost after growth at 37.degree. C for 2 h. Plasmids isolated from genera other than Serratia but incompatible with plasmid R477 were affected differently. Temperature during mating apparently had no effect on transfer efficiency (at least during 10-60 min of incubation). The growth temperature of the donor cells appears to affect an early stage related to the formation of pairs or aggregates of donor and recipient cells. When donor cells carrying plasmid R477 were grown at 37.degree. C and put in direct contact with recipient cells on a solid surface (selective medium), the frequency of transfer was increased to near that of the donor grown at 24.degree. C. The presence of common fimbriae on donor cells, but not on recipient cells, appears to play an important role in the transfer efficiency of the mating apparatus determined by H2 plasmids.