Open AccessLactose metabolism in Lactobacillus curvatus and Lactobacillus sake
Author(s) -
Obst Michaela,
Hehn Roger,
Vogel Rudi F.,
Hammes Walter P.
Publication year - 1992
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1992.tb05465.x
Subject(s) - lactose , catabolite repression , lactococcus lactis , lactobacillus casei , lactobacillus , bacteria , biology , galactose , biochemistry , lactic acid , enzyme , microbiology and biotechnology , beta galactosidase , gene , chemistry , fermentation , escherichia coli , genetics , mutant
The lactose metabolism was investigated in five strains of Lactobacillus curvatus and 14 strains of L. sake isolated from meat or meat‐derived products. Strains with the ability to ferment lactose were found in both species. They exhibited either phospho‐β‐galactosidase (P‐β‐gal) or β‐galactosidase (β‐gal) activity, or both. P‐β‐gal activity of L. curvatus and L. sake was induced and detected only in the presence of lactose or galactose. Furthermore, catabolite repression by glucose was demonstrated. The immunological properties of the P‐β‐gal enzymes of these organisms resemble those of Lactococcus lactis . Several strains of L. sake but none of L. curvatus exhibited β‐gal activity which was constitutive. In hybridisation experiments, the β‐gal genes of L. sake and L. casei ATCC393 showed over 60% DNA‐homology. The presence of β‐gal genes in L. sake was demonstrated in both β‐gal‐producing and non‐producing strains. This observations is consistent with a genetic potential of lactic acid bacteria exceeding their physiological capabilities.