Differentiation of Lactobacillus helveticus, Lactobacillus delbrueckii subsp bulgaricus, subsp lactis and subsp delbrueckii using physiological and genetic tools and reclassification of some strains from the ATCC collection

Several physiological tests of glucose metabolism and genetic tools including species specific probes and 16S rDNA sequences were used to identify strains of L. helveticus and the group of L. delbrueckii with its three subspecies lactis, bulgaricus, and delbrueckii. These species are important for the milk industry as fermenting lactic acid bacteria. The identification procedure was applied to the different strains of these species available from the ATCC collection and allowed to reclassify part of them.