International Committee on Systematic Bacteriology Subcommittee on the taxonomy of Bifidobacterium, Lactobacillus and related organisms

This document records the minutes from the July 1994 meetings of the International Committee on Systematic Bacteriology's Subcommittee on the taxonomy of Bifidobacterium, Lactobacillus and related organisms, held in Prague. The open session featured seven research presentations covering topics including phenotypic and genetic relatedness of Lactobacillus species, taxonomic classification challenges, enzymic activities, rRNA gene patterns, and adhesion mechanisms in bifidobacteria. The closed session addressed membership changes, with W. E. C. Moore's resignation accepted and leadership positions extended. Key discussions focused on safety and pathogenicity of lactic acid bacteria, with emphasis on establishing standards and determining whether pathogenicity is strain-specific or species-specific. The subcommittee acknowledged four new bacterial species and discussed reclassification of lactic acid bacteria into newly proposed genera including Tetragenococcus and Weissella. Taxonomic problems requiring further investigation were identified, particularly within the Lactobacillus casei-paracasei complex and two problematic Bifidobacterium species groups. The subcommittee agreed to develop minimal standards for describing new Bifidobacterium species and planned future collaborative strain and probe exchanges.

Key findings

• Four new bacterial species were acknowledged as valid: Bifidobacterium saeculare, Carnobacterium alterfunditum, Carnobacterium funditum, and Lactobacillus pontis
• The subcommittee identified significant taxonomic problems requiring resolution, particularly within Lactobacillus casei-paracasei complex and two Bifidobacterium species groups
• Multiple Lactobacillus species were reclassified into newly proposed genera Tetragenococcus and Weissella, expanding the subcommittee's scope
• The subcommittee emphasized the need to establish standards for assessing pathogenicity in lactic acid bacteria and determine whether pathogenicity is strain-specific or species-specific
• Plans were made to develop minimal standards for describing new Bifidobacterium species and conduct DNA-DNA homology studies on selected Lactobacillus species