DIFFERENCES IN GENOTYPE OF E. FAECALIS AND E. FAECIUM CLINICAL ISOLATES REGARDING CYTOLYSIN AND GELATINASE PRODUCTION IN BULGARIAN PATIENTS

Abstract

Purpose - compare the phenotype and genotype correlation of cytolysin and gelatinase production in clinical isolates Enterococcus spp. Materials and methods - 100 Enterococcus strains collected over a period of one year from inpatients of two Bulgarian university hospitals, were tested for phenotype production of cytolysin and gelatinase. Multiplex PCR was performed to screen the presence of gelE and cylA virulence genes. Results – 17% of the enterococcal isolates demonstrated only cytolysin production phenotypically. Gelatinase activity was found in 21% of the isolates. Only E. faecalis showed combined phenotypic production of cytolysin plus gelatinase (21%). Forty-five percent of the tested enterococci were identified negative for both hemolysin and gelatinase activity. GelE was the most prevalent virulent gene (48% of the isolates). CylA gene was present alone only in four non-invasive E. faecalis isolates. Twenty-six percent of the isolates possessed both cylA and gelE genes and 21% did not harbor any of the virulence factors genotypically. Conclusion - our results prove that it is appropriate to perform both phenotypic and genotypic analysis of the enterococci virulence profile in parallel in order to better characterize the strains, which in turn may serve to develop more effective methods to limit the spread of infections caused by these microorganisms.