Phylogenetic characterization of two novel species of the genus Bifidobacterium: Bifidobacterium saimiriisciurei sp. nov. and Bifidobacterium platyrrhinorum sp. nov.

Three bifidobacterial Gram-stain-positive, non-spore forming and fructose-6-phosphate phosphoketolase-positive strains, SMA1, SMB2 and SMA15 were isolated from the faeces of two adult males of the squirrel monkey (Saimiri sciureus). On the basis of 16S rRNA gene sequence similarities, the type strain of Bifidobacterium primatium DSM 100687 (99.3%; similarity) was the closest neighbour to strains SMA1 and SMB2, whereas the type strain of Bifidobacterium stellenboschense DSM 23968 (96.5%) was the closest neighbour to strain SMA15. The average nucleotide identity (ANI) values of SMA1 and SAM15 with the closely related type strains were 93.7% and 88.1%, respectively. The in silico DNA‒DNA hybridization values with the closest neighbours were 53.1% and 36.9%, respectively. GC contents of strains SMA1 and SMA15 were 63.6 and 66.4 mol%, respectively. Based on the phylogenetic, genotypic and phenotypic data obtained, the strains SMA1 and SMA15 clearly represent two novel taxa within the genus Bifidobacterium for which the names Bifidobacterium saimiriisciurei sp. nov. (type strain SMA1 = BCRC 81223 = NBRC 114049 = DSM 106020) and Bifidobacterium platyrrhinorum sp. nov. (type strain SMA15 = BCRC 81224 = NBRC 114051 = DSM 106029) are proposed.