['Recently, the dissemination of ESBL (PER-1) among Acinetobacter isolates was reported in Turkish hospitals. We investigated the presence and the association of various virulence determinants in 20 Acinetobacter baumannii isolates, of which 13 were blaPER-1 positive.', 'Virulence tests were slime and hemolysin production, gelatinase and protease activity, biofilm formation, and Caco2 cell adhesion. RAPD analysis was also performed with ERIC primers.', 'None of the strains was positive for slime or hemolysin production and gelatinase or protease activity. A total of 16 strains, five of which were PER-1 gene negative, formed a biofilm on polymer surfaces. There was no relation between the presence of the PER gene and biofilm formation. On the other hand, nine strains (all PER-1 gene positive) were positive in adhesion experiments to Caco2 cell lines. All PER-negative strains were negative for cell adhesion.'] Is pER-1 type beta-lactamase production in Acinetobacter baumannii related to cell adhesion?