Biofilm-Formation Ability and the Presence of Adhesion Genes in Coagulase-Negative Staphylococci Isolates from Chicken Broilers.

Abstract

Simple SummaryBacteria of the genus Staphylococcus are universally present on the mucous membranes and skin of warm-blooded animals. They are divided into two groups on the basis of their ability to clot blood plasma: the coagulase-positive (CoPS) and coagulase-negative staphylococci (CoNS). Some species can cause opportunistic infections in poultry. Identification and characterization of strains of the genus Staphylococcus isolated from farm animals are crucial in epidemiological research and for developing effective methods to treat infections and food poisoning induced by these bacteria. The main virulence factor of coagulase-negative staphylococci is considered to be their ability to form complex biofilm structures on the surfaces of damaged tissues. Biofilms increase the invasive properties of CoNS and their ability to cause infection. The purpose of this study was to determine the biofilm-forming potential of coagulase-negative Staphylococcus strains isolated from poultry. The frequency of selected genes potentially playing a role in the biofilm formation process was also determined. The results of the study indicate that the majority (79.3%) of CoNS isolated from broiler chickens in this study were capable of producing a biofilm.The aim of the study was to analyze the biofilm-production capacity of 87 coagulase-negative Staphylococcus strains (CoNS) isolated from broiler chickens and to determine the occurrence of biofilm-associated genes. The biofilm production capacity of staphylococci was assessed using the microtiter plate method (MTP), and the frequency of genes was determined by PCR. The ability to form a biofilm in vitro was shown in 79.3% of examined strains. Strong biofilm capacity was demonstrated in 26.4% of strains, moderate capacity in 25.3%, weak capacity in 27.6%, and a complete lack of biofilm production capacity in 20.7% of strains. The icaAB gene responsible for the production of extracellular polysaccharide adhesins was detected in 6.9% of strains. The other four genes, i.e., bap (encoding biofilm-associated protein), atlE (encoding cell surface protein exhibiting vitronectin-binding activity), fbe (encoding fibrinogen-binding protein), and eno (encoding laminin-binding protein) were detected in 5.7%, 19.5%, 8%, and 70.1% of strains, respectively. Demonstration of genes that play a role in bacterial biofilm formation may serve as a genetic basis to distinguish between symbiotic and potentially invasive coagulase-negative staphylococcal strains.