Micro-Heterogeneity of Human Saliva Peptide P-C Characterized by High-Resolution Top-Down Fourier-Transform Mass Spectrometry

摘要: Top-down proteomics characterizes protein primary structures with unprejudiced descriptions of expressed and processed gene products. Gene sequence polymorphisms, post-translational modifications, errors can all be identified using top-down proteomics. Saliva offers advantages for proteomic research because availability the noninvasiveness collection and, these reasons, is being used to search disease biomarkers. The description natural variants, intra- inter-individual necessary a complete any proteome, essential discovery Here, we report striking example variants by two new Peptide P-C. Intact mass measurements, collisionally activated-, infrared multiphoton-, electron capture-dissociation, were characterization form predicted from an average 4371 Da, postulated result single nucleotide polymorphism 4372 another 4370 Da arise novel polymorphism. While biological significance such subtle variations in structure remains unclear, their importance cannot assigned without characterization, as reported here one major salivary proteins.