Peptidomics quantitative

Traditional biochemical techniques such as liquid chromatography (LC), gel electrophoresis, capillary electrophoresis (CE), and mass spectrometry (MS) have been widely used for the complete analysis of salivary proteins and peptides. The recent advances in these technical approaches applied to peptidomics have allowed a better comprehensive analysis of peptides in human whole saliva, envisioning the identification of potential salivary biomarkers of oral and systemic diseases. Sample preparation is a critical experimental step for the successful identification of peptides using MS-based approaches, for their quantitation and identification of PTMs. 

FIGURE 1 Flowchart of the peptidomic platforms typically used for the identification and quantitation of salivary peptides. 

One major issue underlying salivary peptidome characterization is peptide quantification. While some quantitative methods developed for proteome studies were inherited, peptidome analysis has its own quantification traits. Direct profiling with MALDI-MS or SELDI-MS has been one of the most widely used approaches for peptidome despite its limitations. For instance, Zhang el al. (32,44) used magnetic beads combined with MALDI-MS for saliva profiling in response to orthodontic procedures, solid foods, and teeth... 

Regarding the dynamic nature of salivary peptidome, it is time to devote more attention to the comprehension of peptidome adaptation to therapeutics based on peptidomic analysis combined with quantitation strategies. 

Che FY, Biswas R, Fricker LD. Relative quantitation of peptides in wild-type and Cpe(fat/fat) mouse pituitary using stable isotopic tags and mass spectrometry. J. Mass Spectrom. 2005 40 227-237. Decaillot FM, Che FY, Fricker LD, Devi LA. Peptidomics of Cpefat/fat mouse hypothalamus and striatum effect of chronic morphine administration. J. Mol. Neurosci. 2006 28 277-284. Naggert JK, Fricker LK, Varlamov O, Nishina PM, Rouille Y, Steiner DF, Carroll RJ, Paigen BJ, Leiter EH. Hyperproinsuli-naemia in obese fat/fat mice associated with a carboxypepti-dase E mutation which reduces enzyme activity. Nat. Genet. 1995 10 135-142. 

High-Resolution Analytical Tools for Quantitative Peptidomics... 

Facdiiano, A., et al. (2010) Standardized sample preparation phases for a quantitative measurement of plasma peptidome profiling by MALDl-TOF. 

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