Choose the statements that correctly describe the structure and function of prot
ID: 508292 • Letter: C
Question
Choose the statements that correctly describe the structure and function of proteasomes:
1, Proteasomes degrade proteins to small peptides.
2. The 26S proteasome unit is composed of a 12S component and a 14S component.
3. Proteasomes would not be expected to use ATP to degrade small, unfolded peptides.
4. The proteasome hydrolyzes the unfolded proteins to free amino acids, which are then recycled.
5. The proteolytic sites of the proteasome are located at the middle of the 20S core.
6. One of the 19S regulatory particles cleaves ubiquitin from the protein.
Explanation / Answer
The proteasome is to degrade unneeded or damaged proteins by proteolysis, a chemical reaction that breaks peptide bonds. Proteasomes are responsible for degrading proteins that have been damaged, assembled improperly, or that are of no profitable use to the cell. The free amino acids can then be recycled to make new proteins. The proteasome is made up of 3 major components, a 20S unit and two 19S subunits, to compose the total 26S proteasome. Proteasomes use ATP to degrade small, unfolded peptides.