Differentiation and identification of Enterococcus durans, E. hirae and E. villorum.
OBJECTIVE
To compare different tests in the identification of Enterococcus durans, E. hirae and E. villorum strains. These bacteria belong to the E. faecium species group and are phylogenetically closely related, as evidenced by 16S rRNA sequence homologies of over 98.8%.


RESULTS
Sodium dodecyl sulphate-polyacrylamide gel electrophoresis analysis of whole-cell protein, tRNA interpacer polymerase chain reaction (PCR) and arbitrarily-primed (D11344-primed AP) -PCR analysis correctly identified all three species in a collection of strains from very diverse origins. In contrast, biochemical reactions only allowed the unequivocal differentiation of the three species as a group from the other enterococci. Within this group, D-xylose acidification can be used to differentiate E. villorum, but exceptions occur. Strains highly susceptible to clindamycin can be identified as E. durans, but many strains of this species cannot be differentiated from E. hirae and E. villorum due to acquired resistance.


CONCLUSIONS
Despite their close relationship, E. durans, E. hirae and E. villorum can be differentiated by genomic methods and by whole-cell protein analysis.


CONCLUSIONS
Only a minority of strains of these three enterococcal species can be identified reliably by the currently available and commonly applied phenotypic tests.
Devriese
L A
LA
Faculty of Veterinary Medicine, University of Ghent, Ghent, Belgium. Luc.Devriese@rug.ac.be
Vancanneyt
M
M
Descheemaeker
P
P
Baele
M
M
Van Landuyt
H W
HW
Gordts
B
B
Butaye
P
P
Swings
J
J
Haesebrouck
F
F
D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry*; D015373:Bacterial Typing Techniques; D002415:Cats; D004269:DNA, Bacterial / Q000032:analysis; D021903:DNA, Ribosomal Spacer / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D016983:Enterococcus / Q000145:classification* / Q000235:genetics* / Q000378:metabolism; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods; D016133:Polymerase Chain Reaction / Q000379:methods; D012343:RNA, Transfer / Q000235:genetics
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D021903:DNA, Ribosomal Spacer; D012343:RNA, Transfer