Referenced in: none

Automatically associated channels: Kir2.3

Title: High sensitivity identification of membrane proteins by MALDI TOF-MASS spectrometry using polystyrene beads.

Authors: Noura Bensalem, Sandrine Masscheleyn, Julien Mozo, Benoit Vallée, Franck Brouillard, Stéphanie Trudel, Daniel Ricquier, Aleksander Edelman, Ida Chiara Guerrera, Bruno Miroux

Journal, date & volume: J. Proteome Res., 2007 Apr , 6, 1595-602

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/17355127

Abstract
Membrane proteins play a large variety of functions in life and represent 30% of all genomes sequenced. Due to their hydrophobic nature, they are tightly bound to their biological membrane, and detergents are always required to extract and isolate them before identification by mass spectrometry (MS). The latter, however remains difficult. Peptide mass fingerprinting methods using techniques such as MALDI-TOF MS, for example, have become an important analytical tool in the identification of proteins. However, PMF of membrane proteins is a real challenge for at least three reasons. First, membrane proteins are naturally present at low levels; second, most of the detergents strongly inhibit proteases and have deleterious effects on MALDI spectra; and third, despite the presence of detergent, membrane proteins are unstable and often aggregate. We took the mitochondrial uncoupling protein 1 (UCP1) as a model and showed that differential acetonitrile extraction of tryptic peptides combined with the use of polystirene Bio-Beads triggered high resolution of the MALDI-TOF identification of mitochondrial membrane proteins solubilized either with Triton-X100 or CHAPS detergents.