Organism diversity between women with and without bacterial vaginosis as determined by polymerase chain reaction denaturing gradient gel electrophoresis and 16S rRNA gene sequence

Aims: The aim of this study was to characterize the different structures of microbial communities between 20 healthy women and 17 bacterial vaginosis (BV)-positive women of reproductive age using denaturing gradient gel electrophoresis (DGGE). Material and Methods: Vaginal samples from 17 BV-positive and 20 BV-negative women were subjected to DNA extraction, and amplified with eubacterial 16S rRNA gene-specific primers via polymerase chain reaction. The polymerase chain reaction products were separated using DGGE. Bands were excised, re-amplified, purified and sequenced. DNA sequences were compared with GenBank database. Phylip software packages were used to calculate sequencing data and form a phylogenetic tree to identify the genetic relations for microbiota inhabited in vaginal ecosystems of BV-positive women. Results: In total, 28 kinds of organisms were detected that comprised BV(+) vagina microbial community, varying from three to nine kinds with an average of 5.71 kinds per woman. Only seven species were detected in BV(-) women, ranging between one and five species with an average of 2.40 species per woman, which was significantly lower than that detected in BV(+) women (t = 7.39, P < 0.001). A strain of Uncultured Lactobacillus sp. clone EHFS1_S05c (29/37; 78.38%) was most commonly presented in both BV-negative and BV-positive women, but the mean proportion of this Lactobacillus sp. strain to the whole microbial population colonized in the vaginal tract of BV(-) women was sharply higher than that calculated from BV(+) women (t = 2.92, P < 0.01). Conclusions: The findings indicate further diversity in the category of vaginal microorganisms associated with BV. The presence of Gardnerella vaginalis is not necessary as a sign for gynecologists to determine whether or not a woman is affected by BV.