MALDI-TOF Mass Spectrometry Analysis of Amphipol-Trapped Membrane Proteins

Amphipols (APols) are amphipathic polymers with the ability to substitute detergents to keep membrane proteins (MPs) soluble and functional in aqueous solutions. APols also protect MPs against denaturation. Here, we have examined the ability of APol-trapped MPs to be analyzed by matrix-assisted lase...

Full description

Saved in:

Bibliographic Details
Published in:	Analytical chemistry (Washington) Vol. 84; no. 14; pp. 6128 - 6135
Main Authors:	Bechara, Chérine, Bolbach, Gérard, Bazzaco, Paola, Sharma, K. Shivaji, Durand, Grégory, Popot, Jean-Luc, Zito, Francesca, Sagan, Sandrine
Format:	Journal Article
Language:	English
Published:	Washington, DC American Chemical Society 17-07-2012
Subjects:	Algae Amino Acid Sequence Analytical chemistry Animals Aqueous solutions Cattle Chemical Sciences Chemistry Chloroplasts Detergents - chemistry Exact sciences and technology Hydrophobic and Hydrophilic Interactions Immobilized Proteins - analysis Immobilized Proteins - chemistry Immobilized Proteins - metabolism Mass spectrometry Membrane Proteins - analysis Membrane Proteins - chemistry Membrane Proteins - metabolism Membranes Molecular Sequence Data Organic chemistry Peptide Fragments - analysis Peptide Fragments - chemistry Peptide Fragments - metabolism Polymers - chemistry Proteins Solubility Spectrometric and optical methods Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization - methods Trypsin - metabolism Membrane protein Stabilization Escherichia coli Eukaryote Lipids Matrix assisted laser desorption ionization Subunit Cofactor Mitochondria Signal Bacteria Membrane Ungulata Chloroplast Enterobacteriaceae Detergent Bovine Denaturation Use Polymer Vertebrata Mammalia Time of flight method Artiodactyla Aqueous solution Mass spectrometry
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	Amphipols (APols) are amphipathic polymers with the ability to substitute detergents to keep membrane proteins (MPs) soluble and functional in aqueous solutions. APols also protect MPs against denaturation. Here, we have examined the ability of APol-trapped MPs to be analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). For that purpose, we have used ionic and nonionic APols and as model proteins (i) the transmembrane domain of Escherichia coli outer membrane protein A, a β-barrel, eubacterial MP, (ii) Halobacterium salinarum bacteriorhodopsin, an α-helical archaebacterial MP with a single cofactor, and (iii, iv) two eukaryotic MP complexes comprising multiple subunits and many cofactors, cytochrome b 6 f from the chloroplast of the green alga Chlamydomonas reinhardtii and cytochrome bc 1 from beef heart mitochondria. We show that these MP/APol complexes can be readily analyzed by MALDI-TOF-MS; most of the subunits and some lipids and cofactors were identified. APols alone, even ionic ones, had no deleterious effects on MS signals and were not detected in mass spectra. Thus, the combination of MP stabilization by APols and MS analyses provides an interesting new approach to investigating supramolecular interactions in biological membranes.
Bibliography:	ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23
ISSN:	0003-2700 1520-6882
DOI:	10.1021/ac301035r