NEW LACTIC ACID BACTERIA

The present invention relates to lactose-positive, sucrose-negative, Streptococcus thermophilus strains. The strains are carrying one or more mutation in one or more gene of the sucrose regulon and optionally one or more further mutation affecting the glucose porter, such as affecting glcU and/or its expression. The strains of the present invention may further carry mutations in genes encoding a protein of the mannose-glucose-specific PTS and a glucokinase, a protein of the mannose-glucose-specific PTS and the catabolite control protein A (CcpA), and/or a protein of the mannose-glucose-specific PTS, a glucokinase and CcpA. The inventive strains may, when fermenting milk do this without the need or with a need for adding a reduced amount of sucrose, optionally providing a low-lactose fermented milk and/or a fermented milk not undergoing post-acidification when stored at fermentation temperature. The invention also concerns a composition comprising at least one, lactose-pos- itive, sucrose-negative, Streptococcus thermophilus strain of the invention, and the use of this strain or composition to manufacture a fermented dairy product.