Journal
JOURNAL OF PROTEOME RESEARCH
Volume 16, Issue 9, Pages 3443-3447Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acs.jproteome.7b00022
Keywords
alkylation; cysteine alkylation; N-terminal alkylation; artifact; post-translational modification
Categories
Funding
- Australian Cancer Research Foundation (ACRF)
- Office for Health and Medical Research (OHMR) NSW, Australia
- Cancer Institute NSW (CINSW) as a Translational Program Grant (TPG)
- National Health & Medical Research Council (NHMRC) Australia [GNT1069493, GNT1047070, GNT1032771]
Ask authors/readers for more resources
Iodoacetamide is by far the most commonly used agent for alkylation of cysteine during sample preparation for proteomics. An alternative, 2-chloroacetamide, has recently been suggested to reduce the alkylation of residues other than cysteine, such as the N-terminus, Asp, Glu, Lys, Ser, Thr, and Tyr. Here we show that although 2-chloroacetamide reduces the level of off-target alkylation, it exhibits a range of adverse effects. The most significant of these is methionine oxidation, which increases to a maximum of 40% of all Met-containing peptides, compared with 2-5% with iodoacetamide. Increases were also observed for mono- and dioxidized tryptophan. No additional differences between the alkylating reagents were observed for a range of other post-translational modifications and digestion parameters. The deleterious effects were observed for 2-chloroacetamide from three separate suppliers. The adverse impact of 2-chloroacetamide on methionine oxidation suggests that it is not the ideal alkylating reagent for proteomics.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available