RETENTIVE AND ENANTIOSELECTIVE PROPERTIES OF OVOMUCOID-BONDED SILICA COLUMNS - INFLUENCE OF PROTEIN PURITY AND ISOLATION METHOD

The influence of protein purity and isolation method on the chiral resolution of racemates on ovomucoid-bonded materials has been investigated. Chicken ovomucoid (OMCHI) and turkey ovomucoid (OMTKY) were obtained from commercial sources, and were isolated by precipitation with acetone from their corresponding egg whites. Further, crude OMCHI protein was fractionated by cation-exchange chromatography into two fractions, pure OMCHI and an unknown protein fraction. The OMCHI, fractionated OMCHI and OMTKY proteins were characterized by N-terminal sequencing and trypsin-inhibitory activity. Their purity was checked by reversed-phase chromatography. The results reveal that the commercial OMCHI, and the isolated OMCHI and OMTKY are crude preparations and that an unknown protein fraction is present in each crude ovomucoid protein. The OMCHI, fractionated OMCHI and OMTKY proteins were bound to aminopropyl-silica gels activated by N,N'-disuccinimidyl carbonate to test the retentive and enantioselective properties of those materials. The result suggests that the unknown protein fraction could be responsible for chiral recognition ability of the OMCHI and OMTKY columns.