Purification and Some Properties of the Endo α-1,4 Polygalactosaminidase from Pseudomonas sp.

The endo α-1,4 polygalactosaminidase from Pseudomonas sp. 881 was purified from the culture nitrate by ethanol precipitation and sequential column chromatographies on CM-Sephadex C-25, Sephadex G-50 and Phenyl-Sepharose CL-4B. The purified enzyme was electrophoretically homogeneous and its molecular weight and isoelectric point were 31,000 and 6.7, respectively. The optimum pH and temperature for hydrolysis of polygalactosamine were 5.0 and 55°C, respectively. The enzyme was stable up to 45°C for 15min and from pH 4.0 to 7.6 at 37°C for 1 hr.

The Km value was 0.05% α-1,4 polygalactosamine and the V was 0.154μmol reducing sugar (galactosamine)/min/μg protein. This polygalactosaminidase was inhibited by Sn²⁺ , Fe²⁺ , Fe³⁺ , Hg²⁺, Cu²⁺ ions and SDS. The enzyme did not hydrolyze oligo galactosamines (n < tetramer) or N-acetyl-polygalactosamines. It acted only on oligo galactosamine (n > trimer) and polygalactosamine endogeneously so far tested.