Culture-dependentandculture-independentmethodswerecombinedfortheinvestigationofaceticacidbacteria
(AAB) populations in traditionally produced vinegars and mother of vinegar samples obtained from apple and
grape. The culture-independent denaturing gradient gel electrophoresis (DGGE) analysis, which targeted the
V7–V8 regions of the 16S rRNA gene, showed that Komagataeibacter hansenii and Komagataeibacter europaeus/
Komagataeibacter xylinus were the most dominant species in almost all of the samples analyzed directly. The
culture-independent GTG 5 -rep PCR fingerprinting was used in the preliminary characterization of AAB isolates
and species-level identification was carried out by sequencing of the 16S rRNA gene, 16S–23S rDNA internally
transcribedto thespacer(ITS)region and tufgene.Acetobacterokinawensiswasfrequentlyisolatedfromsamples
obtained from apple while K. europaeus was identified as the dominant species, followed by Acetobacter
indonesiensis in the samples originating from grape. In addition to common molecular techniques, real-time
PCR intercalating dye assays, including DNA melting temperature (Tm) and high resolution melting analysis
(HRM),wereappliedtoaceticacidbacterialisolatesforthefirsttime.ThetargetsequenceofITSregiongenerated
species-specific HRM profiles and Tm values allowed discrimination at species level.