Egg-yolk trypsin inhibitor identical to albumen ovomucoid

Two preparations of trypsin inhibitor were purified from yolk, one from unincubated hen's eggs and the other from those at day 16 of incubation. Both were indistinguishable from albumen ovomucoid with respect to molecular weight, isoelectric point, peptide map after limited proteolysis, immunological reactivity and so forth. Although a gap in specific activity was observed, it was concluded that the yolk inhibitors were species of ovomucoid. This suggested a flow of ovomucoid from egg white to yolk during embryonic development.