Pseudomonas aeruginosa is an opportunistic human pathogen of clinical importance that causes airway infections in immunocompromised patients. Here, we report the virulence-associated characteristics of strains of P. aeruginosa, isolated from the sputa of 25 Korean pneumonia patients. A high degree of genomic plasticity was observed by random amplified polymorphic DNA genotype analysis, suggesting that the infections were caused by strains with diverse genomic backgrounds. Biofilm formation of each isolate was heterogeneous in terms of their relative motilities. In addition, 48% of isolates were defective in the production of 3-oxo-C12-HSL (PAI-1), a quorum sensing signal molecule. In these strains, PAI-1-dependent elastase production was correspondingly decreased, suggesting that a large number of strains were presumed to be quorum sensing deficient. Multidrug resistance (MDR) was seen in 56% of the isolates tested, and 44% of the MDR strains were resistant to five or more antibiotics. Taken together, our results provide additional insights into the virulence traits of P. aeruginosa clinical isolates, which will aid in treating P. aeruginosa infections in pneumonia patients.
Bibliographical noteFunding Information:
This study was supported by a grant of the Korea Healthcare technology R&D Project, Ministry for Health, Welfare and Family Affairs, Republic of Korea, A090951 and by the National Research Foundation of Korea (NRF) grant funded by the Korea Government (MEST) (No. 2009-0087951). We are thankful for Dr. Joon-Hee Lee (Department of Pharmacy, College of Pharmacy, Pusan National University) for providing the pKDT17 plasmid DNA.
All Science Journal Classification (ASJC) codes
- Applied Microbiology and Biotechnology