HETEROGENEITY OF PROTEINS IN BIRDS’ EGG-WHITES

Little is known about the comparative heterogeneity of protein compounds among a wide variety of birds’ egg white, particularly, an analysis of their detailed, in-parallel protein composition. Hence this research is conducted mainly to evaluate the extent of variability among 42 types of birds’ egg white. To improve the perception of these biological fluids, the main phenotypic variations of egg whites were evaluated using the discontinuous denaturing polyacrylamide gel electrophoresis (SDS-PAGE), Gradient SDS-PAGE, Native-PAGE, cellulose acetate electrophoresis, and the reverse-phase high-performance liquid chromatography (RP-HPLC). The results showed that the Native-PAGE and SDS-PAGE produced better screening results than other methods in identifying protein. Although  Native-PAGE and SDS-PAGE did not show remarkable variability in terms of hydrophobicity, several electrophoretic differences of egg-white proteins were observed. Several unknown proteins in the egg white samples of different bird species were also identified through the electrophoretic experiments. Hence, it might be possible, as in the case of egg white samples, to provide a characterized assessment among birds by using only the available gel electrophoresis techniques. This study also provided a rapid snapshot of the initial identification of several unknown components of egg white proteins. Accordingly, this study constituted the first large-scale comparative proteomics investigation performed among the largely varying types of egg whites from commercial stores and bird keepers in the middle Euphrates areas in Iraq.