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Is disulfide bond formation a redox reaction?

Is disulfide bond formation a redox reaction?

The formation of a disulfide bond from two cysteine residues is a redox half reaction. Hence it requires electron acceptors that can take up the released electrons. Disulfide bonds can move from one cysteine–cystine couple to another. This reaction is called a thiol–disulfide exchange reaction (Figure 1.2.

Can disulfide bonds be oxidized?

Whilst the reactions of Cys are well characterized, little is known about oxidation of disulfides, despite their high abundance in some proteins. Recent data indicate that some disulfides are rapidly oxidized by a range of oxidants, with rate constants, k, 105–107 M-1 s-1.

What is disulfide bond reduction?

Disulfide-reducing reagents are routinely used in biochemical manipulations for (i) reducing the native disulfide bonds in proteins and (ii) maintaining the essential thiol groups in proteins by preventing their oxidation to the disulfide state. Dithiothreitol (DTT) is the most popular disulfide-reducing reagent.

What is disulfide interchange?

The disulfide exchange (also called interchange) process involves attack of the thiol at the disulfide, breaking the -S–S- bond, with subsequent formation of a new mixed disulfide comprising a portion of the original disulfide compound (Reaction 3.23). These bonds are reversible using disulfide reducing agents.

Where do disulfide bridges form?

Disulfide bond formation generally occurs in the endoplasmic reticulum by oxidation. Therefore disulfide bonds are mostly found in extracellular, secreted and periplasmic proteins, although they can also be formed in cytoplasmic proteins under conditions of oxidative stress.

Where are disulfide bridges formed?

the endoplasmic reticulum
Disulfide bond formation generally occurs in the endoplasmic reticulum by oxidation. Therefore disulfide bonds are mostly found in extracellular, secreted and periplasmic proteins, although they can also be formed in cytoplasmic proteins under conditions of oxidative stress.

Where does disulfide bridge come from?

A disulfide bridge is formed when a sulfur atom from one cysteine forms a single covalent bond with a sulfur atom from a second cysteine. When a disulfide bridge forms, each cysteine loses one hydrogen atom.

How is a disulfide bridge formed?

A disulfide bridge is formed when a sulfur atom from one cysteine forms a single covalent bond with a sulfur atom from a second cysteine. When a disulfide bridge forms, each cysteine loses one hydrogen atom. The atom count for other amino acids changes only at the N terminal and C terminal ends of the chain.