Antagonistic and antiadhesive effects of two Lactobacillus probiotics against Pseudomonas aeruginosa isolated from burn patients

Abstract

Aims: Today, probiotic bacteria can be used as safe and suitable candidates for the prevention of pathogenic bacterial infections. They produce antimicrobial components and compete with pathogens for host cell receptors. The present study aimed at evaluating probiotic lactobacilli antagonistic and antiadhesive activities against multi-antibiotic resistant Pseudomonas aeruginosa isolated from burned patients. Methodology and results: This study examined 100 strains of multidrug-resistant (MDR) P. aeruginosa isolated from patients, who were admitted to the burn units of hospitals. Antagonistic activity of Lactobacillus casei and Lactobacillus plantarum against P. aeruginosa was determined by a modified double layer and well diffusion methods. The antiadhesive effects of two probiotic lactobacilli and co-aggregation assay were determined by the microtiter plate method. Finally, the expression of two main adhesion genes, algD, and pelA was investigated in 100 MDR P. aeruginosa isolates via real-time polymerase chain reaction (RT-PCR) assay. Based on the results, the algD gene was detected in 97 out of 100 P. aeruginosa isolates, and the pelA gene was found in all of the isolates. Based on our findings, lactobacilli bacteria exerted good inhibitory effects on P. aeruginosa, especially on algD and pelA expression. Also, co-aggregation and antiadhesive results showed the positive effects of lactobacilli on P. aeruginosa. Conclusion, significance and impact of study: Probiotic lactobacilli can be a new suitable candidate for controlling P. aeruginosa infections.