[Preliminary study on multi-resistant gene location of 20 strains of Pseudomonas aeruginosa].

20 strains of Pseudomonas aeruginosa were isolated from burn patients of Xijing Hospital in Xi'an. These 20 strains which showed resistance to multiple antibiotics were selected to be studied regarding the location of multi-resistant gene. According to the sensitivity tests before and after plasmid removal, we found that in 70% of the bacteria resistance to multiple antibiotics was mediated by the plasmid. In 30% the bacteria remained resistant to antibiotics after plasmids were removed. Two explanations were postulated. (1) plasmids were not removed completely; (2) resistance gene was encoded by the chromosomes.