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Published on: May 4, 2018
Anticandidal activity of Pseudomonas aeruginosa strains isolated from clinical specimens
Ilknur Kaleli1, Nural Cevahir, Melek Demir
1Department of Microbiology, Medical School, Pamukkale University, Denizli, Turkey.
Abstract:
Pseudomonads represent the major group of non-differentiating microorganisms that produce antibiotics. The antibiotic substances produced by this group of organisms are pyocyanin, pyrolnitrin and pseudomonic acid. This study was designed to investigate the in vivo and in vitro anticandidal activity of Pseudomonas aeruginosa strains against Candida species. Forty-four P. aeruginosa strains isolated from various specimens of intensive care patients were included in the study. All P. aeruginosa strains have pyocyanin pigment. Candida albicans ATCC 10231, Candida parapsilosis ATCC 22019, Candida krusei ATCC 6258 and a clinical isolate of Candida tropicalis were used to measure the anticandidal activity of Pseudomonas strains by Kerr's method. The total inhibition rates obtained by using blood agar of C. albicans, C. parapsilosis, C. krusei and C. tropicalis were 41%, 34%, 34% and 25% respectively. When Sabouraud dextrose agar (SDA) was used, the rates were detected as 45%, 39%, 48% and 25% respectively. In the mouse model of concomitant subcutaneous infection with Candida species and P. aeruginosa no yeast were recovered from skin cultures despite 100% detection of P. aeruginosa. Pseudomonas aeruginosa strains isolated from intensive care patients showed anticandidal activity against the Candida species in the present study and this point may be important in the following and treatment of patients.
Insights
Pseudomonas aeruginosa strains from intensive care units show significant antibiotic activity against Candida species in lab tests and mouse models. This finding suggests potential therapeutic applications for these bacteria in treating fungal infections.
Area of Science:
- Microbiology
- Infectious Diseases
- Pharmacology
Background:
- Pseudomonads are known antibiotic producers, including pyocyanin, pyrolnitrin, and pseudomonic acid.
- Candida species are common opportunistic fungal pathogens, particularly in immunocompromised individuals.
- The anticandidal potential of Pseudomonas aeruginosa, especially strains from clinical settings, requires further investigation.
Purpose of the Study:
- To evaluate the in vitro and in vivo anticandidal activity of Pseudomonas aeruginosa strains against various Candida species.
- To assess the efficacy of P. aeruginosa strains isolated from intensive care patients against Candida infections.
Main Methods:
- Forty-four P. aeruginosa strains from intensive care patients were tested.
- Anticandidal activity was measured against Candida albicans, Candida parapsilosis, Candida krusei, and Candida tropicalis using Kerr's method on blood agar and Sabouraud dextrose agar (SDA).
- An in vivo mouse model assessed P. aeruginosa efficacy in concomitant subcutaneous infections with Candida species.
Main Results:
- P. aeruginosa strains demonstrated varying inhibition rates against Candida species on different agar media, with SDA yielding higher rates (up to 48%).
- In a mouse model, P. aeruginosa successfully inhibited Candida recovery from skin cultures when coinoculated, despite 100% P. aeruginosa detection.
- All tested P. aeruginosa strains produced pyocyanin pigment.
Conclusions:
- Pseudomonas aeruginosa strains isolated from intensive care patients exhibit significant anticandidal activity.
- These findings highlight the potential of P. aeruginosa as a source of antifungal agents or as a therapeutic agent itself.
- Further research into the mechanisms and clinical application of P. aeruginosa's anticandidal properties is warranted for patient treatment strategies.
