A number of -like organisms were recently recognized as human pathogens. Five -like strains were proposed as members of the new species (with type strain E2 [= NCTC 12142]) on the basis of the results of a 16S rRNA sequence analysis. The intraspecies phenotypic and genetic relatedness of 22 selected strains was investigated, and a hitherto unrecognized esculin hydrolysis-positive biotype was identified. A total of 14 of the 15 more common esculin-negative strains exhibited very high DNA relatedness as determined by the hydroxyapatite method (the levels of relatedness were greater than 90% in 55 and 70°C reactions, with 1.5% or less divergence in related sequences). The DNA relatedness among the six esculin-positive strains was more heterogeneous, and two DNA hybridization subgroups were formed. Our results are compatible with the hypothesis that both biotypes are members of the single species , which contains two or more genetic subspecies. The putative subspecies have not been formally proposed since they cannot be definitively differentiated. The inclusion of in the genus is supported by the results of 16S rRNA sequencing. The rRNA sequence data also is compatible with placing both biotypes in a single species.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error