[en] A new Bifidobacterium species is described based on the study of ten Gram-positive strains with fructose-6-phosphate phosphoketolase activity. They are part of a phenotypic group comprising 141 strains isolated from raw milk and raw milk cheeses in French raw milk cheese factories. This group was separated by a numerical analysis based on API 50CH, API 32A tests and growth at 46 degrees C. A strong similarity of 16S rRNA sequences (99.8%) was shown between strain FR62/b/3(T) and Bifidobacterium psychraerophilum LMG 21775(T). However, low DNA-DNA relatedness was observed between their DNAs (31%). The new isolates are able to grow at low temperatures (all ten strains up to 5 degrees C) and strain FR62/b/3(T) grows under aerobic conditions, as does B. psychraerophilum. However, contrary to B. psychraerophilum, they do not ferment L-arabinose, D-xylose, arbutin or melezitose, but they do acidify lactose. The DNA G+C content of FR62/b/3(T) is 56.4mol%. Therefore, the name Bifidobacterium crudilactis sp. nov. is proposed, with its type strain being FR62/b/3(T) (=LMG 23609(T)=CNCM I-3342(T)).
Commission européenne : Direction générale de la Recherche