[Studies of plasmids of Pseudomonas maltophilia]

Eighteen strains of P. maltophilia were screened for the occurrence of plasmid using four different methods. Five of them were harbor plasmids. The results of plasmid detection in different growth phase of P2 strain showed that the highest amount of plasmids in the strain was observed in stationary growth phase. The characteristics of plasmid of P. maltophilia P2 was investigated by methods of agarose gel electrophoresis, restriction endonucleases analysis, determination of molecular weight. The results indicated that P. maltophilia P2 contained only one type of plasmid, its molecular weight was 4.4 x 10(6) dalton and that the plasmid had single BamHI. PstI. XbaI EcoRI. HindIII sites. Thus, the plasmid of P. maltophilia P2 may be developed into a fine cloning vector.