title: Identification of five reptile egg whites protein using MALDI-TOF mass spectrometry and LC/MS-MS analysis.
abstract: Proteomics of egg white proteins of five reptile species, namely Siamese crocodile (Crocodylus siamensis), soft-shelled turtle (Trionyx sinensis taiwanese), red-eared slider turtle (Trachemys scripta elegans), hawksbill turtle (Eretmochelys imbricate) and green turtle (Chelonia mydas) were studied by 2D-PAGE using IPG strip pH 4-7 size 7 cm and IPG strip pH 3-10 size 24 cm. The protein spots in the egg white of the five reptile species were identified by MALDI-TOF mass spectrometry and LC/MS-MS analysis. Sequence comparison with the database revealed that reptile egg white contained at least seven protein groups, such as serpine, transferrin precursor/iron binding protein, lysozyme C, teneurin-2 (fragment), interferon-induced GTP-binding protein Mx, succinate dehydrogenase iron-sulfur subunit and olfactory receptor 46. This report confirms that transferrin precursor/iron binding protein is the major component in reptile egg white. In egg white of Siamese crocodile, twenty isoforms of transferrin precursor were found. Iron binding protein was found in four species of turtle. In egg white of soft-shelled turtle, ten isoforms of lysozyme were found. Apart from well-known reptile egg white constituents, this study identified some reptile egg white proteins, such as the teneurin-2 (fragment), the interferon-induced GTP-binding protein Mx, the olfactory receptor 46 and the succinate dehydrogenase iron-sulfur subunit.
authors.affiliation: Protein and Proteomics Research Group, Department of Biochemistry, Faculty of Sciences, Khon Kaen University, Khon Kaen, Thailand 40002.
authors.forename: Bung-on
authors.initials: BO
authors.lastname: Prajanban
authors.forename: Laoo
authors.initials: L
authors.lastname: Shawsuan
authors.forename: Sakda
authors.initials: S
authors.lastname: Daduang
authors.forename: Jintana
authors.initials: J
authors.lastname: Kommanee
authors.forename: Sittiruk
authors.initials: S
authors.lastname: Roytrakul
authors.forename: Apisak
authors.initials: A
authors.lastname: Dhiravisit
authors.forename: Sompong
authors.initials: S
authors.lastname: Thammasirirak
mesh_terms: D000489:Alligators and Crocodiles; D000818:Animals; D002645:Chickens; D002853:Chromatography, Liquid; D004527:Egg Proteins / Q000737:chemistry*; D004529:Egg White / Q000737:chemistry*; D004591:Electrophoresis, Polyacrylamide Gel; D006023:Glycoproteins / Q000032:analysis; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D053719:Tandem Mass Spectrometry; D014426:Turtles
chemical_list: D004527:Egg Proteins; D006023:Glycoproteins