Carbamidomethylation
Carbamidomethylation — The alkylation of cysteine residues with iodoacetamide, commonly performed before mass spectrometry analysis to prevent disulfide bond reformation.
What Is Carbamidomethylation?
Carbamidomethylation is the alkylation of free thiol groups (Cys side chains) with iodoacetamide, adding a carbamidomethyl group (+57.02 Da). This irreversible modification caps reduced cysteines, preventing disulfide bond re-formation during peptide mapping and proteomic analysis. It is a standard sample preparation step.
Workflow
- Reduce: DTT or TCEP breaks disulfide bonds to free thiols
- Alkylate: Iodoacetamide (IAA) in the dark for 30 min caps all free Cys residues
- Digest: Trypsin digestion for MS analysis. Cys residues appear at +57 Da
Frequently Asked Questions
What is Carbamidomethylation?
The alkylation of cysteine residues with iodoacetamide, commonly performed before mass spectrometry analysis to prevent disulfide bond reformation.
Why is Carbamidomethylation important in peptide research?
Carbamidomethylation is a fundamental concept in modification as it relates to peptide science. It directly influences experimental design, compound characterization, and the reliability of research outcomes across biochemistry and molecular biology disciplines.
Authority Sources
- Carbamidomethylation on Wikipedia
- Search Carbamidomethylation on PubChem (NIH)
- Research articles on ScienceDirect