Disulfide bridge

Definition

A disulfide bridge is a covalent bond formed between two cysteine residues within or between protein molecules. It plays a crucial role in stabilizing the three-dimensional structure of proteins.

5 Must Know Facts For Your Next Test

1. Disulfide bridges are formed through the oxidation of sulfhydryl (–SH) groups on cysteine residues.
2. These bonds contribute significantly to the stability and functionality of extracellular proteins.
3. Enzymes like protein disulfide isomerase help form and rearrange disulfide bonds within proteins during their folding process.
4. Disulfide bridges are commonly found in secreted proteins, antibodies, and receptor molecules.
5. The presence and correct formation of disulfide bridges can be critical for the biological activity of certain microbial enzymes.

Review Questions

Related terms

Cysteine: An amino acid that contains a thiol group which can form disulfide bonds.

Protein Folding:

The process by which a protein assumes its functional three-dimensional structure.

Protein Disulfide Isomerase: An enzyme that catalyzes the formation and rearrangement of disulfide bonds in proteins.