Association among Biofilm Formation, Serogroups, and Virulence Factors in Listeria monocytogenes Isolated from Food, Clinical, and Livestock Sources

Abstract

were collected from blood, urine, feces, placenta, rectum, and vagina samples as well as livestock and food samples. Biofilm production was measured using microtiter plate assay, and virulence genes were identified by PCR method. Findings: Out of 51 isolates, 27 (52.9%) were non-biofilm producers, 17 (33.3%) were weak biofilm producers, four (7.8%) were medium biofilm producers, and three (5.9%) were strong biofilm producers. According to this study results, different L. monocytogenes strains could form biofilm with various intensities. The actA plcB genes were observed in all the isolates. The frequency of the hlyA, plcA, iap, inlB , and inlC genes among the isolates was 90.2, 94.1, 98, 88.2, and 82.4%, respectively. There was no significant correlation between the presence/absence of virulence genes in biofilm producing and non-biofilm forming isolates, except for the inlC and iap genes, which showed a significant correlation with the ability to form biofilm. Conclusions: Due to the high prevalence rate of biofilm formation among the isolates the importance of biofilm production in medical surfaces and food industries, eradication of isolates is important.