3
$\begingroup$

In my biochemistry practicals, we used reducing agents such as beta mercaptoethanol:

enter image description here

and dithiothreitol (DTT)

enter image description here

Both of these have S-H groups, and I am sure that these are involved in the reduction process. However I am not sure as to how. I know that when you have two S-H groups close to one another in cysteine residues in amino acids that form a disulfide bridge, which must be oxidation because I know they are reduced in the reducing environment of the cytosol (hence are not found in cytosolic proteins, in general):

enter image description here

The only way I can think of that S-H groups act as reducing agents is when they form disulfide bridges between them, and an electron (and H+ ion) is released. Is this what happens? If so, it would result in two molecules of the beta mercaptoethanol becoming bonded together, and with the DTT it could either form a long chain with S-H groups between molecules reacting, or it could form rings of any size in which the end S-H groups form a disulfide bridge. I think this should result in the solution becoming viscous and 'gooey' due to the long chains and larger molecules.

Is this how S-H groups can act as reducing agents?

$\endgroup$
  • $\begingroup$ I guess you're more or less right. $\endgroup$ – Mithoron May 4 '17 at 16:00

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.