Ovalbumin is the major and mostabundant chicken egg white protein and it was one of the first proteins to beisolated in a and kinin cascades, as well as proteins without any pure form (Abeyrathneet al., 2013). Ovalbuminis a glycoprotein with the molecular mass of 45 kDa. The amino acid sequence ofchicken egg-white ovalbumin consisting with 386 amino acids (James et al., 2001). Other than the synthesis of ovalbumin in oviduct ofhen it is regulating by steroid hormones has provided (Hunt et al.
, 1980; James et al., 2001). The native form of ovalbumin is coagulated easilyupon heating, but it can be converted into distinct, heat stable form calledS-ovalbumin by using invitro incubation under alkaline conditions (YasushiSugimoto et al., 1999).
There arethree components (A1, A2 and A3) of ovalbuminwith different electrophoretic. However, the electrophoretic differences weredue to differences in ovalbumin phosphorous content. A1 componenthas two phosphate groups per mole protein, A2 has one phosphategroup per mole protein and A3 has no phosphate group (Ana ClaudiaCarraro Alleoni, 2006).
When considering the amino acid sequence of ovalbumin,it is consisting with six cysteines with a single disulfide bond between Cys74and Cys 121 (McReynolds et al., 1978; James etal., 2001). Ovalbumin does not have classical N-terminal leader sequence,although it is a secretory protein. Researcher have founded that there are twogenetic polymorphisms of ovalbumin (GLu-Gln substitution at residue 290 and anAsn-Asp substitution at residue 312. However, ovalbumin does not have proteaseinhibitory activity despite sequence identity of about 30% with antitrypsin andother functional inhibitors of the serpin family (James et al.
, 2001). And also, it acts as a substrate not as an inhibitorof enzyme. However, ovalbumin plays a role in chick embryo development (James et al., 2001).