Typing of Enterococcus species by DNA restriction fragment analysis

Abstract

Enterococci are a frequent cause of hospital-acquired infection, being associated with urinary tract infections, wound sepsis, bacteremia, and endocarditis. The source of infection is usually thought to be endogenous, but some evidence points to cross-infection between patients. A better understanding of the epidemiology of enterococci has been limited by the lack of a good discriminatory typing system. This report describes the application of two DNA-based typing methods to Enterococcusfaecalis and Enterococcusfaecium: comparison of restriction fragments from total DNA by conventional electrophoresis and comparison of restriction fragments hybridizing to an rRNA gene probe (ribotyping). Comparison of restriction fragments (from SstI digestion) by conventional electrophoresis was simple and highly discriminatory. The results of analysis of blood culture isolates and of repeat isolates from individual patients are reported. Ribotyping (with BscI digestion) was more applicable at the level of species discrimination.by gentamicin-resistant Streptococcus faecalis: an epidemiological study.

Evaluation of ribosomal RNA gene restriction patterns for the classification of Bacillus species and related genera

“…Ribosomal RNA gene restriction pattern analysis has been used for the identi®cation and classi®cation of bacterial species within a variety of genera such as Legionella (Saunders et al 1988), Campylobacter (Moureau et al 1989), Lactococcus (Rodrigues et al 1991), Staphylococcus (Chesneau et al 1992;De Buyser et al 1992), Enterococcus (Hall et al 1992), Borrelia (Fukunaga et al 1993), Lactobacillus (Ning et al 1997) and Helicobacter (Jalava et al 1999). The use of ribosomal RNA gene restriction pattern has proved very useful for classi®cation purpose and is regarded as a key taxonomic tool for bacterial species (Gannon 1994).…”

Production of bacteriolytic enzymes as a tool for characterizing enterococci

“…This agrees with previous reports indicating that Ent. faecalis is phylogenetically distant from other enterococcal species and apparently includes strains which are not homogeneous in their physiological and genetic behaviours (Hall et al 1992;Devriese and Collins 1993). Zymogram analysis of lytic activities therefore appears to be a useful tool for strain differentiation within the species Ent.…”

Epidemiology of Enterococcus faecalis urinary tract infection in a teaching hospital in London, United Kingdom

“…The survey was conducted from January to October 1989, during which all enterococcal isolates were collected. Identification of isolates has been described elsewhere (7). Patients were from an ethnically diverse local population or referred from elsewhere in the country.…”

“…Pulsed-field electrophoresis of restriction fragments has shown the relatedness of a number of P-lactamase-producing E. faecalis isolates across the United States (15), while ribotyping has been used to demonstrate the unrelatedness of vancomycin-resistant E. faecium isolates in one hospital in France (2). In our laboratory, a simpler method that uses conventional electrophoresis of restriction fragments was shown to be highly discriminatory for enterococci (7). In the present study, we used this method to type E. faecalis urine isolates obtained from four sets of patients at the Royal London Hospital over a 9-month period.…”