title: Ovalbumin subfractionation and individual difference in ovalbumin microheterogeneity.
abstract: Purified ovalbumin from hen egg white was fractionated by concanavalin A (Con A)/Sepharose chromatography. Four major fractions were separated, one unadsorbed fraction OA, followed by a minor fraction OA', and three adsorbed fractions OB, OC, and OD. The recovery was over 90%. Fractional ratios (OA:OB:OC:OD) were 16:6:37:41. The amino acid composition of the four fractions were quite similar. Galactose was only detected in OA, and the mannose content in OD was high as compared to that of the other fractions. The glycopeptide resulting from pepsin digestion of ovalbumin was also fractionated by Con A/Sepharose. Four fractions were obtained, and they corresponded to fractions OA, OB, OC, and OD. The amino acid compositions of the peptides were identical, indicating that they were derived from the same region in ovalbumin. In order to study individual differences in ovalbumin microheterogeneity, ovalbumin samples prepared from individual eggs were subfractionated on Con A/Sepharose. Four ovalbumin samples prepared from the eggs of a single hen revealed the same elution profile and the same fractional ratios. Fractional ratios of 17 individual preparations varied from 7:2:19:72 to 27:5:40:28 (OA:OB:OC:OD). A constant relation was found among the fractional ratios: the OB, OC and OD contents were dependent on the OA content, and the proportion of OD was in inverse relation to those of OA and OC. The OB content was low and did not change in all ranges of OA content. The present observations indicate that a single hen produces ovalbumin with qualitatively and quantitatively similar carbohydrate chains by unknown mechanisms; moreover, individual differences exist in ovalbumin microheterogeneity which follow constant patterns.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002241:Carbohydrates / Q000032:analysis; D002645:Chickens; D002846:Chromatography, Affinity; D003208:Concanavalin A; D004529:Egg White; D005260:Female; D008970:Molecular Weight; D010047:Ovalbumin / Q000302:isolation & purification*
chemical_list: D000596:Amino Acids; D002241:Carbohydrates; D003208:Concanavalin A; D010047:Ovalbumin