Hydrolysis of (1->6)-beta-D-galactosidic linkages in arabinogalactan proteins and (1->3):(1->6)-beta-galactans to yield (1->6)-beta-galactobiose as the final product.
Comment
The enzyme, characterized from the bacterium Bifidobacterium longum, specifically hydrolyses (1->6)-beta-galactobiose from the non-reducing terminal of (1->6)-beta-D-galactooligosaccharides with a degree of polymerization (DP) of 3 or higher, using an exo mode of action. The enzyme cannot hydrolyse alpha-L-arabinofuranosylated (1->6)-beta-galactans (as found in arabinogalactans) and does not act on (1->3)-beta-D- or (1->4)-beta-D-galactans. cf. EC 3.2.1.164, galactan endo-1,6-beta-galactosidase.
