Since the description of the first Lactobacillus species, Lactobacillus delbrueckii, in 1901, over 260 species were assigned to this genus until March 2020. The availability of new DNA analysis tools over the years has shown that genus Lactobacillus was too diverse and did not conform to nomenclature conventions.

According to several genetic approaches and phenotypic or ecologic criteria, a team of  15 scientists (from 12 different institutions and 7 different countries proposed to split genus Lactobacillus into 25 genera: the emended genus Lactobacillus, (with, for instance, the species L. delbrueckii, L. acidophilus and L. helveticus), genus Paralactobacillus and 23 novel genera, such as, among other, Lacticaseibacillus (which includes Lacticaseibacillus casei, former L. casei) and Lactiplantibacillus (which includes Lactiplantibacillus plantarum, former L. plantarum). The reclassification was accepted and published on the International Journal of Systematic and Evolutionary Microbiology.

The novel genera now comprise species characterised by common physiological, metabolic properties and lifestyles; this will facilitate the functional and ecological studies on these bacteria, unveiling the mechanisms that are at the basis of the health benefits and technological properties of some species.

To assist the stakeholders (including consumers) in the transition between the old and new names, the researchers involved in this project developed a user-friendly web-based app at the following links:
http://lactobacillus.ualberta.ca
http://lactobacillus.uantwerpen.be
http://lactotax.embl.de/wuyts/lactotax/

by Elisa Salvetti
PhD., Marie S. Curie Alumna, Senior Post-Doctoral Fellow at University of Verona and Consultant in Food Microbiology