Polyphasic study of wine Lactobacillus strains: taxonomic implications.

One hundred and seventy-eight lactobacilli isolated from wine were characterized by a polyphasic approach. Strains were phenotypically identified at genus and species level by classical tests including the analysis of cell morphology, homo/heterofermentative character, sugar fermentation patterns, growth at different temperatures and the optical nature of the isomer of lactic acid produced from glucose. Molecular techniques such as random amplification of polymorphic DNA (RAPD), amplified 16S rDNA restriction analysis (16S-ARDRA), PFGE-RFLP and ribotyping were used to characterize strains, and their potential for identification and/or typing was evaluated. The information obtained with these techniques was processed with the BioNumerics software in order to analyse relationships existing between isolated strains and various reference species of the genus. Then, taxonomic dendrograms were obtained, and this information allowed the proposal of molecular procedures suitable for the identification and typing of these wine micro-organisms. The techniques useful for both identification and typing were RAPD and ribotyping, while 16S-ARDRA was only useful for identification and PFGE-RFLP only for typing purposes. The wine strains were identified as Lactobacillus brevis (19 strains), Lactobacillus collinoides (2 strains), Lactobacillus hilgardii (71 strains), Lactobacillus paracasei (13 strains), Lactobacillus pentosus (2 strains), Lactobacillus plantarum (34 strains) and Lactobacillus mali (10 strains).