Comparative sequence analysis of a recA gene fragment brings new evidence for a change in the taxonomy of the Lactobacillus casei group.

The taxonomic positions of species of the Lactobacillus casei group have been evaluated by sequencing and phylogenetic analysis of a 277 bp recA gene fragment. High sequence similarity between strain ATCC 393T, currently designated as the type strain of L. casei, and the type strain of Lactobacillus zeae, LMG 17315T, has been established, while L. casei ATCC 334 and Lactobacillus paracasei NCDO 151T form a single phylogenetic group. The taxonomic status of species and strains at issue is discussed.