Enzymatic Conversion of RBCs by α-N-Acetylgalactosaminidase from Spirosoma linguale.

Spirosoma linguale is a free-living nonpathogenic organism. Like many other bacteria, S. linguale produces a cell-associated α-N-acetylgalactosaminidase. This work was undertaken to elucidate the nature of this activity. The recombinant enzyme was produced, purified, and examined for biochemical attributes. The purified enzyme was ~50 kDa active as a homodimer in solution. It catalyzed hydrolysis of α-N-acetylgalactosamine at pH 7. Calculated KM was 1.1 mM with kcat of 173 s-1. The described enzyme belongs to the GH109 family.