Ovalbumin (OVA)

Ovalbumin is the main protein found in egg white, making up 60-65% of the total protein. While Ovalbumin displays sequence and three-dimensional homology to the serpin superfamily, it is a noninhibitory serpin . While most serpins control such processes as fibrinolysis and coagulation by inhibiting serine proteases, the function of ovalbumin is unknown, although it is presumed to be a storage protein.

The ovalbumin protein of chickens is made up of 385 amino acids, and its relative molecular mass is 45 kDa. It is a glycoprotein with 4 sites of glycosylation.It is secreted from the cell. Unlike the signal sequences of most secreted proteins, Ovalbumin's signal sequence is not cleaved. Additionally it is not located directly on the N-terminus, but rather internally, starting at residue 21 and ending at residue 47.