Phenotypic and genotypic diversity of vaginal bacteria Gardnerella vaginalis resulted in its classification into genotypic subgroups. The virulence potential of these subgroups was evaluated.


clinical isolates were subtyped on the basis of subgroup-specific genes by PCR. The virulence-related phenotypic characteristics of the isolates were evaluated assessing their in vitro ability to grow as biofilm on abiotic surfaces, produce the toxin vaginolysin, and express sialidase activity. Vaginolysin in the supernatant of the cultures was quantified using toxin-specific antibodies by sandwich ELISA. Sialidase activity was tested using fluorogenic substrate. Cloning and expression of the sialidase gene of in was performed. Differences in the expression of phenotypic properties of the isolates were evaluated by agglomerative hierarchical clustering and principal component analysis.


Thirty-five clinical isolates of were subtyped into three subgroups 1, 2 and 4. Analysis of sialidase activity indicated statistically significant differences among the subgroups. All isolates were grouped into three clusters by the methods of statistical analysis. The distinct profile of each cluster was based on the phenotypic characteristics of isolates. Subgroup 4 was the most homogenous group, as all isolates were found in the same cluster, which was characterized by the low production of all studied virulence factors. Subgroup 2 isolates were mainly distributed between two clusters, whereas subgroup 1 isolates were found in all three clusters.


G. vaginalis subgroups with different virulence potential might play distinct roles in vaginal microbiota.

  • This is an open-access article distributed under the terms of the Creative Commons Attribution License.

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