Ovalbumin in a and kinin cascades, as well

Ovalbumin is the major and most
abundant chicken egg white protein and it was one of the first proteins to be
isolated in a and kinin cascades, as well as proteins without any pure form (Abeyrathne
et al., 2013). Ovalbumin
is a glycoprotein with the molecular mass of 45 kDa. The amino acid sequence of
chicken egg-white ovalbumin consisting with 386 amino acids (James et al., 2001). Other than the synthesis of ovalbumin in oviduct of
hen it is regulating by steroid hormones has provided (Hunt et al., 1980; James et al., 2001). The native form of ovalbumin is coagulated easily
upon heating, but it can be converted into distinct, heat stable form called
S-ovalbumin by using invitro incubation under alkaline conditions (Yasushi
Sugimoto et al., 1999). There are
three components (A1, A2 and A3) of ovalbumin
with different electrophoretic. However, the electrophoretic differences were
due to differences in ovalbumin phosphorous content. A1 component
has two phosphate groups per mole protein, A2 has one phosphate
group per mole protein and A3 has no phosphate group (Ana Claudia
Carraro Alleoni, 2006). When considering the amino acid sequence of ovalbumin,
it is consisting with six cysteines with a single disulfide bond between Cys74
and Cys 121 (McReynolds et al., 1978; James et
al., 2001). Ovalbumin does not have classical N-terminal leader sequence,
although it is a secretory protein. Researcher have founded that there are two
genetic polymorphisms of ovalbumin (GLu-Gln substitution at residue 290 and an
Asn-Asp substitution at residue 312. However, ovalbumin does not have protease
inhibitory activity despite sequence identity of about 30% with antitrypsin and
other functional inhibitors of the serpin family (James et al., 2001). And also, it acts as a substrate not as an inhibitor
of enzyme. However, ovalbumin plays a role in chick embryo development (James et al., 2001).