Determine Biofilm Genes in Pseudomonas Aeruginosa Isolated from Clinical and Environmental Samples

Abstract

Objective: Isolates of Pseudomonas aeruginosa are an extremely adaptable bacterium that causes opportunistic diseases because of its varied metabolic pathways, genes, virulence factors, and considerable antibiotic resistance. Methods: A total of 293 samples were collected from different places: 193 samples (% 65.87) of human samples and 100 samples (% 34.13) of wastewater samples in the period between 3rd September to 15th November 2023). Bacterial isolates were identified according to microscopic, cultural, and genetic characteristics. Antibiotic susceptibility of bacterial isolates was determined against twelve of the selected antibiotics. The biofilm production was done by using phenotypic ways (Congo red agar and Microtiter plate methods) as well as genotypic ways by detection of biofilm genes (algD, pelf, and pslD genes). Results: Hundred-forty eight bacterial isolates were obtained, and sixty of these isolates were identified as Pseudomonas spp. (40.9%), twenty-six isolates of E. coli (17.9%), seventeen isolates of K. pneumoniae (11.3%), and forty-five isolates were beyond to other types of bacteria (30.1%), and out of sixty isolates of Pseudomonas spp., forty-two were identified as P. aeruginosa isolates. P. aeruginosa isolates revealed various resistance levels to antimicrobial agents gradually, ranging from 83.87% to Trimethoprim-sulfamethoxazole (SXT) to 3.22% to Aztreonam (AZT). Biofilm production by using the Congo red method showed that 27 isolates (64.28%) were positive results, while in the microtiter method, all forty-two isolates were positive (100%), the genetic detection showed that the AlgD gene was recognized in thirty-one isolates (73.8%), followed by Pelf and PslD genes in four isolates each (9.5%). Conclusion: The isolation percentage showed a high occurrence of multi-drug resistance biofilm forming Pseudomonas spp. isolates which could be a critical indicator. Methods of biofilm detection showed that the microtiter plate method has accuracy more than the Congo red method; as well AlgD gene was prevalent compared with both other genes Pelf, and PslD.