title: Romancing the "hidden proteome", Anno Domini two zero zero seven.
abstract: The mechanism of action and properties of a solid-phase ligand library made of hexapeptides, for capturing the "hidden proteome", i.e. the low- and very low-abundance proteins constituting the vast majority of species in any proteome, be it a cell or tissue lysate or a biological fluid, are here reviewed. Mechanisms of adsorption are evaluated, as well as different protocols for en bloc or sequential elution of the captured polypeptides. Examples are given of capture of proteins from serum, human platelet extracts, bacterial extract and egg white. The increment in detection of low-abundance species appears to be of at least four-fold as compared with untreated samples. One particular aspect of this capture is the adsorption of a high proportion of small peptides (in the Mr 600-8000 Da range) that are normally lost upon electrophoretic two-dimensional mapping. Such a peptide population, in human sera, may be of particular importance since it may contain protein cleavage products of diagnostic value.
authors.affiliation: Ciphergen Biosystems, Fremont, California, USA.
authors.forename: Egisto
authors.initials: E
authors.lastname: Boschetti
authors.forename: Lee
authors.initials: L
authors.lastname: Lomas
authors.forename: Attilio
authors.initials: A
authors.lastname: Citterio
authors.forename: Pier Giorgio
authors.initials: PG
authors.lastname: Righetti
mesh_terms: D001792:Blood Platelets / Q000737:chemistry; D002556:Cerebrospinal Fluid Proteins / Q000032:analysis; D020650:Combinatorial Chemistry Techniques; D004527:Egg Proteins / Q000032:analysis; D004591:Electrophoresis, Polyacrylamide Gel; D029968:Escherichia coli Proteins / Q000032:analysis; D006801:Humans; D008970:Molecular Weight; D009842:Oligopeptides / Q000737:chemistry*; D019151:Peptide Library; D011507:Proteinuria / Q000652:urine; D020543:Proteome / Q000737:chemistry* / Q000302:isolation & purification; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D002556:Cerebrospinal Fluid Proteins; D004527:Egg Proteins; D029968:Escherichia coli Proteins; D009842:Oligopeptides; D019151:Peptide Library; D020543:Proteome