Effects of agr genotype on biofilm-forming ability in Staphylococcus pseudintermedius isolates from broiler chickens

The Accessory Gene Regulator (agr) operon as part of the quorum-sensing system, is responsible for regulating numerous virulence factors in Staphylococci. Furthermore, the ability of the opportunistic pathogen Staphylococcus pseudintermedius to form biofilm is a significant contributor to chronic diseases. Our aim was to evaluate of the association between different agr groups and the expression of the icaD gene related to biofilm formation among S. pseudintermedius isolates from nasal samples. Fifty nasal swabs were collected from broiler chickens and phenotypic and molecular tests were performed to isolate S. pseudintermedius from the samples and investigate their agr genotype. The biofilm production capacity of the isolates was determined using both a microtiter plate assay and amplification of the icaD gene. The S. pseudintermedius was detected in the ۸۶.۸۴% of samples. The assessment of agr typing results revealed that most of the strains (۶۹.۷۰%) were classified in agr group I. The relative frequency of biofilm producing S. pseudintermedius isolates was ۷۵.۷۶% and all of them harbored the icaD gene. The expression level of the icaD determinant was significantly higher among isolates in agr group I than other agr groups. These results suggest that broiler chickens may act as a reservoir for the transmission of S. pseudintermedius to humans which should be considered a potential zoonotic bacterium capable of producing different virulence factors like biofilms.

کلیدواژه ها:

agr group ، biofilm ، Broiler chicken ، icaD gene ، Staphylococcus pseudintermedius