Virulence determinants and production of extracellular enzymes in Enterococcus spp. from surface water sources.
Virulence factors in Enterococcus may be indicative of potential pathogenicity. The aim of this study was to determine the relationship between the presence of clinically relevant virulence genes, in Enterococcus spp. from environmental water, and their in vitro expression. One hundred and twenty-four Enterococcus isolates (seven species), from five surface water systems in the North West Province, South Africa, were screened for the presence of asa1, cylA, esp, gelE and hyl using polymerase chain reaction. The expression of cylA, hyl and gelE was determined by phenotypic assessments. Sixty-five percent of the isolates were positive for one virulence gene and 13% for two or more. Most frequently detected genes were gelE (32%) and cylA (28%). Enterococcal surface protein was absent in all isolates screened. The presence of virulence genes was correlated with their extracellular enzyme production. The results show that a large percentage of these environmental Enterococcus spp. possess virulence factors that could be expressed in vitro. This is a cause for concern and could have implications for individuals using this water for recreational and cultural purposes. Further investigation is required into the sources of these potential pathogenic Enterococcus isolates and measures to minimize their presence in water sources.
Unit for Environmental Sciences and Management: Microbiology, North-West University, Potchefstroom Campus, Private Bag X6001, Potchefstroom 2520, South Africa E-mail: carlos.bezuidenhout@nwu.ac.za.
Lesego Gertrude
LG
Molale
Unit for Environmental Sciences and Management: Microbiology, North-West University, Potchefstroom Campus, Private Bag X6001, Potchefstroom 2520, South Africa E-mail: carlos.bezuidenhout@nwu.ac.za.
Cornelius Carlos
CC
Bezuidenhout
D001426:Bacterial Proteins / Q000378:metabolism; D016983:Enterococcus / Q000201:enzymology* / Q000472:pathogenicity*; D006801:Humans; D008565:Membrane Proteins; D016133:Polymerase Chain Reaction; D013019:South Africa; D014774:Virulence; D037521:Virulence Factors; D014867:Water / Q000737:chemistry*; D014871:Water Microbiology
D001426:Bacterial Proteins; D008565:Membrane Proteins; D037521:Virulence Factors; D014867:Water