[Purification and characterization of beta-fructofuranosidase from yeast Saccharomyces cerevisiae]

Intracellular invertase was isolated from the yeast Saccharomyces cerevisiae, race XI, and purified by ion-exchange chromatography on DEAE-cellulose and gel-filtration on Sephadex G-200. The effect of pH, temperature, metal ions, thiolic agents, and EDTA on the enzyme activity and stability was investigated. The enzyme was estimated to have a molecular weight of 270 000 and a carbohydrate content of 20--30%. By disc-electrophoresis and isoelectric focusing the highly purified enzyme was found to be heterogenous. Its molecular forms had isoelectric points at 3.0, 4.0, 4.5, and 4.9.