PICquant: a quantitative platform to measure differential peptide abundance using dual-isotopic labeling with 12C6- and 13C6-phenyl isocyanate.
Anal Chem
; 83(3): 856-65, 2011 Feb 01.
Article
en En
| MEDLINE
| ID: mdl-21192683
ABSTRACT
We have developed a complete system for the isotopic labeling, fractionation, and automated quantification of differentially expressed peptides that significantly facilitates candidate biomarker discovery. We describe a new stable mass tagging reagent pair, (12)C(6)- and (13)C(6)-phenyl isocyanate (PIC), that offers significant advantages over currently available tags. Peptides are labeled predominantly at their amino termini and exhibit elution profiles that are independent of label isotope. Importantly, PIC-labeled peptides have unique neutral-mass losses upon CID fragmentation that enable charge state and label isotope identification and, thereby, decouple the sequence identification from the quantification of candidate biomarkers. To exploit these properties, we have coupled peptide fractionation protocols with a Thermo LTQ-XL LC-MS(2) data acquisition strategy and a suite of automated spectrum analysis software that identifies quantitative differences between labeled samples. This approach, dubbed the PICquant platform, is independent of protein sequence identification and excludes unlabeled peptides that otherwise confound biomarker discovery. Application of the PICquant platform to a set of complex clinical samples showed that the system allows rapid identification of peptides that are differentially expressed between control and patient groups.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Péptidos
/
Espectrometría de Masas
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Isocianatos
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Marcaje Isotópico
Tipo de estudio:
Guideline
Límite:
Humans
Idioma:
En
Revista:
Anal Chem
Año:
2011
Tipo del documento:
Article
País de afiliación:
Estados Unidos