Guidelines for characterizing LAB, bifidobacteria and related genera for taxonomic purposes

The bacterial groups of bifidobacteria, lactic acid bacteria (LAB) and related species are prominent examples of the need for comprehensive descriptions of isolates in order to correctly allot them to taxonomic units, and furthermore to provide such information as is required when the potential of their practical usefulness or their pathogenic nature has to be evaluated. Great progress has been made with regard, for example, toward revealing the taxonomic relationships of LABspecies (Zhang et al., 2011) but still there are several species described that escape routine taxonomic treatment because just one strain is available and little more than morphology and 16S RNA description are known (Hammes & Hertel, 2009). In a taxonomic note, Tindall et al. (2010) have presented the key elements in the way prokaryotes should be characterized. These recommendations are the background for our contribution, and aspects specific for bifidobacteria and LAB are included.