%0 Journal Article %A Masco, Liesbeth %A Ventura, Marco %A Zink, Ralf %A Huys, Geert %A Swings, Jean %T Polyphasic taxonomic analysis of Bifidobacterium animalis and Bifidobacterium lactis reveals relatedness at the subspecies level: reclassification of Bifidobacterium animalis as Bifidobacterium animalis subsp. animalis subsp. nov. and Bifidobacterium lactis as Bifidobacterium animalis subsp. lactis subsp. nov. %D 2004 %J International Journal of Systematic and Evolutionary Microbiology, %V 54 %N 4 %P 1137-1143 %@ 1466-5034 %R https://doi.org/10.1099/ijs.0.03011-0 %K ERIC, Enterobacterial Repetitive Intergenic Consensus %K rep, repetitive DNA element %K FAFLP, Fluorescent Amplified Fragment Length Polymorphism %I Microbiology Society, %X The taxonomic standing of Bifidobacterium lactis and Bifidobacterium animalis was investigated using a polyphasic approach. Sixteen representatives of both taxa were found to be phenotypically similar and shared more than 70 % DNA–DNA relatedness (76–100 %), which reinforces the conclusions of previous studies in which B. lactis and B. animalis were considered to be one single species. However, the results of protein profiling, BOX-PCR fingerprinting, Fluorescent Amplified Fragment Length Polymorphism (FAFLP), and atpD and groEL gene sequence analysis demonstrate that representatives of B. animalis and B. lactis constitute two clearly separated subgroups; this subdivision was also phenotypically supported based on the ability to grow in milk. Given the fact that B. lactis Meile et al. 1997 has to be considered as a junior synonym of B. animalis (Mitsuoka 1969) Scardovi and Trovatelli 1974 , our data indicate that the latter species should be split into two new subspecies, i.e. Bifidobacterium animalis subsp. animalis subsp. nov. (type strain R101-8T=LMG 10508T=ATCC 25527T=DSM 20104T=JCM 1190T) and Bifidobacterium animalis subsp. lactis subsp. nov. (type strain UR1T=LMG 18314T=DSM 10140T=JCM 10602T). %U https://www.microbiologyresearch.org/content/journal/ijsem/10.1099/ijs.0.03011-0