Screening and Identification of Characteristic Peptides of Donkey-hide Gelatin Based on Bio-informatics Technique and Mass Spectrometry
Abstract:Objective:To establish a new method based on biological information technology and liquid chromatography mass spectrometry technology to identify characteristic peptides for the identification of E-jiao(donkey-hide gelatin).Methods:Homologous comparison of the α1 chain amino acid sequences of type I collagen from donkey skin,cow skin and pig skin using bioinformatics technology showed that there were differences in amino acid sequences of three kinds of skin collagen.The trypsin digest was simulated by biological software,and the enzymolysis peptides of type I collagen from donkey skin,cow skin and pig skin were compared.Then,the sample pretreatment conditions were systematically explored through experiments,and ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometer(UPLC/Q-TOF-MS)for verification.Results:Twelve specific peptides of donkey-hide were screened out,and one donkey specific peptides was identified in accordance with the predicted results with a mass-to-charge ratio(m/z)of 766.4,mass of 1 530.802 2,corresponding peptide sequence of GEAGPAGPAGPIGPVGAR.Ten groups of donkey-hide gelatin samples were identified by using characteristic peptides.Conclusion:The detection characteristic peptide in the digested gelatins using UPLC/Q-TOF-MS coupled with bio-informatics technique could be used to identify E-jiao effectively,specifically and accurately.