What is N-Ethylmaleimide used for?
N-Ethylmaleimide (NEM) is an organic compound that is derived from maleic acid. It contains the amide functional group, but more importantly it is an alkene that is reactive toward thiols and is commonly used to modify cysteine residues in proteins and peptides.
How do you prepare n-Ethylmaleimide?
Prepare 100-200mM of NEM in ultrapure water. Add a minimum of a 10-fold molar excess of NEM to sulfhydryl groups to be blocked. Alternatively, add an equal mass amount of NEM to the protein (e.g., add 2mg of NEM to 1mL of 2mg/mL protein).
How do you dissolve NEM?
Dissolve 25 g NEM in ethanol and adjust volume to 100 ml. Store in aliquots at -20°C. NEM inhibits thiol proteases and prevents nonspecific disulfide exchange. Pepstatin A (0.2 mg/ml).
How does N Ethylmaleimide work?
Thermo Scientific Pierce N-Ethylmaleimide (NEM) is a small compound that forms stable, covalent thioether bonds with sulfhydryls (e.g., reduced cysteines), enabling them to be permanently blocked to prevent disulfide bond formation.
Is NEM cell permeable?
NEM a cell permeable, well known cysteine protease inhibitor. Most of the literature suggests it is used as an inhibitor during cell lysis for immunoprecipitation and western blotting.
What does the sulfhydryl group do?
The sulfhydryl group not only constitutes a unique marker for delineating the general role of proteins in membrane functions, it can also serve as a marker for specific functional proteins through the use of radioactive reagents that form stable bonds with sulfhydryls.
What does cysteine do to the body?
Cysteine is a non-essential amino acid important for making protein, and for other metabolic functions. It’s found in beta-keratin. This is the main protein in nails, skin, and hair. Cysteine is important for making collagen.
Does protein contain sulfhydryl groups?
Sulfhydryls, also called thiols, exist in proteins in the side-chain of cysteine (Cys, C) amino acids. Pairs of cysteine sulfhydryl groups are often linked by disulfide bonds (–S–S–) within or between polypeptide chains as the basis of native tertiary or quaternary protein structure.