Comparative studies on protein isolates from different yeasts prepared by isoelectric precipitation and ultrafiltration

Protein isolates prepared from yeasts by isoelectric precipitation and ultrafiltration, respectively, show differences in their solubility and gelchromatographic behaviour. The ultrafiltrated preparation represents a less aggregated protein. The SDS-discelectrophoresis patterns are identical, which is a proof for an identical protein polypeptide distribution in the isoelectric precipitated and ultrafiltrated samples

Significant differences were found between ultrafiltrated proteins from Saccharomyces cerevisiae and Candida guilliermondi yeasts using SDS-disc-electrophoresis, gel chromatography, as well as determination of solubility profiles, amino acid composition, and thiol/disulphide content

All the main fractions of the isolated protein posses a molecular weight distribution mainly in the range of 50000-70000. The polypeptide patterns in the SDS-electrophoresis are characterized by a great number of zones in the molecular weight range of 10000-60000.