title: Synthesis of acid-cleavable light isotope-coded affinity tags (ICAT-L) for potential use in proteomic expression profiling analysis.
abstract: A convenient synthesis of some homologous light isotope-coded affinity tags (ICAT-L) containing an acid-labile moiety between the affinity component biotin and an electrophilic polar linker is described. These light ICAT reagents give smooth mass spectral signals in tandem mass spectrometry (MS/MS) analyses of some commercially available cysteine-containing peptides. However, these ICAT molecules are designed for use in identification and relative quantification of whole or partially purified cellular and tissue proteomes. Since the biotin moiety can be readily cleaved off the reagent after mass tagging, undesired residual fragmentation patterns caused by biotin of derived peptides, as normally observed using biotin-containing ICAT reagents, are effectively eliminated. This strategy should enhance peptide sequence coverage significantly which, in turn, should result in improving the quality of data obtained during data-dependent peptide mass and tandem mass spectral analysis of whole proteomes.
authors.affiliation: Chemistry Core Facility, Mayo Clinic Jacksonville, 4500 San Pablo Road, Jacksonville, Florida 32224, USA. Fauq.abdul@mayo.edu
authors.forename: Abdul H
authors.initials: AH
authors.lastname: Fauq
authors.forename: Rajashaker
authors.initials: R
authors.lastname: Kache
authors.forename: Murad A
authors.initials: MA
authors.lastname: Khan
authors.forename: Irving E
authors.initials: IE
authors.lastname: Vega
mesh_terms: D001710:Biotin / Q000737:chemistry; D020869:Gene Expression Profiling; D006851:Hydrochloric Acid / Q000737:chemistry; D007202:Indicators and Reagents / Q000138:chemical synthesis* / Q000737:chemistry; D007553:Isotope Labeling; D013058:Mass Spectrometry; D010455:Peptides; D040901:Proteomics
chemical_list: D007202:Indicators and Reagents; D010455:Peptides; D001710:Biotin; D006851:Hydrochloric Acid