A highly purified preparation of α-D-galactosidase [E.C. 18.104.22.168] isozymes was obtained from Phaseolus vulgaris (pinto bean) seeds by extraction, salt precipitation, ion exchange, and affinity chromatography. The final preparation was homogeneous by SDS-PAGE but revealed isozymes of relative mass of 38.3 and 39.6 kDa. The N-terminal sequence for both isozymes was identical, LANGLAKT (one letter code for amino acids). Relative native molecular mass was estimated at 149.3 kDa by Sephacryl S-200 chromatography. Activity was unaffected by ionic strength at high enzyme concentrations, and was specific for α-D-galactoside conjugates. No protease or haemagglutinin activity was detected, and activity was stable at 4°C. Studies with soluble oligosaccharides demonstrated high activity against the selected straight and branched-chain substrates. The enzyme was active against terminal α1-3 galactosyl residues on human and rabbit erythrocyte membranes. Because of its activity against membrane glycoconjugates, these isozymes may have potential utility for modifying membrane epitopes on native erythrocytes.
|Original language||English (US)|
|Number of pages||8|
|Journal||Biochemistry and Molecular Biology International|
|State||Published - Jan 1 1994|
ASJC Scopus subject areas
- Molecular Biology