Alkylation of cysteine residues is a component of virtually any proteomics workflow. Despite its frequent use, up so far no systematic investigation of the impact of various conditions on the result of proteomics studies has been performed. during this study, we compared common reduction reagents (dithiothreitol, tris-(2-carboxyethyl)-phosphine, and β-mercaptoethanol) and alkylation reagents (iodoacetamide, iodoacetic acid, acrylamide, and chloroacetamide). We observed strong differences in offsite alkylation reactions at 7 amino acids also as at the peptide N terminus, identifying single and double adducts of all reagents. We observed differences of quite 9-fold in numbers of identified methionine-containing peptide spectral matches for in-gel digested samples between iodine- and noniodine-containing alkylation reagents. This was due to formation of carbamidomethylated and carboxymethylated methionine side chains and a resulting prominent neutral loss during ESI ionization or in MS/MS fragmentation, strongly decreasing identification rates of methionine-containing peptides. We achieved best results with acrylamide as alkylation reagent, whereas the very best numbers of peptide spectral matches were obtained when reducing with dithiothreitol and β-mercaptoethanol for the in-solution and therefore the in-gel digested samples, respectively.
Editorial: Journal of Pharmacognosy & Natural Products
Editorial: Journal of Pharmacognosy & Natural Products
Research Article: Journal of Pharmacognosy & Natural Products
Research Article: Journal of Pharmacognosy & Natural Products
Research Article: Journal of Pharmacognosy & Natural Products
Research Article: Journal of Pharmacognosy & Natural Products
Posters & Accepted Abstracts: Pharmacoeconomics: Open Access
Posters & Accepted Abstracts: Pharmacoeconomics: Open Access
Posters & Accepted Abstracts: Journal of Bioprocessing & Biotechniques
Posters & Accepted Abstracts: Journal of Bioprocessing & Biotechniques
Posters & Accepted Abstracts: Journal of Pharmacognosy & Natural Products
Posters & Accepted Abstracts: Journal of Pharmacognosy & Natural Products
Keynote: Journal of Bioanalysis & Biomedicine
Keynote: Journal of Bioanalysis & Biomedicine
Accepted Abstracts: Pharmaceutical Regulatory Affairs: Open Access
Accepted Abstracts: Pharmaceutical Regulatory Affairs: Open Access
Journal of Pharmacognosy & Natural Products received 606 citations as per Google Scholar report
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