Biofilm Formation and Antibiotic Resistance in Arcobacter butzleri Strains Isolated from Environmental Sources

Abstract

In recent years, a marked increase in antimicrobial resistance among microorganisms has been reported. One of the key factors contributing to this phenomenon is the formation of biofilms—structured microbial communities that significantly enhance bacterial survival and resistance to external stressors. The present study aimed to assess the biofilm-forming potential of selected Arcobacter butzleri strains isolated from environmental sources. This evaluation included the molecular detection of six biofilm-associated genes (flaA, flaB, spoT, fliS, luxS, and pta), which are involved in bacterial motility, invasiveness, and pathogenicity. All six target genes were detected in 21 strains (42%), while 6 strains (12%) tested negative for all investigated genes. Biofilm formation was quantitatively assessed under static and dynamic conditions using Christensen’s colorimetric assay. Under static conditions, biofilm formation was observed in 96% of the strains, with 74% classified as strong or moderate biofilm producers. Conversely, biofilm development was markedly reduced under dynamic conditions, with up to 80% of strains exhibiting limited adhesion capacity.