Proteasome Mechanism: Threonine Hydrolysis

The video explains the mechanism of the 26S proteasome, which degrades damaged proteins in cells. It covers the structure and function of the proteasome, highlighting the role of ATP hydrolysis in unfolding proteins. The catalytic mechanism involves a threonine residue and catalytic water, differing from typical serine proteases by not using a histidine residue. The process generates peptides, not individual amino acids, which are further recycled.

What is the primary function of the 26S proteasome in cells?

• To synthesize proteins

• To transport proteins

• To degrade damaged proteins

• To modify proteins

Which residue plays a crucial role in the catalytic mechanism of the proteasome?

• Serine

• Aspartate

• Cysteine

• Threonine

What is generated during the hydrolysis of proteins by the proteasome?

• Amino acids

• Tetrahedral intermediate

• Nucleotides

• Carbohydrates

How does the proteasome differ from serine proteases in its mechanism?

• It forms a catalytic triad

• It uses the N-terminal amine and catalytic water

• It does not form a tetrahedral intermediate

• It uses a histidine residue

What is the final product released from the proteasome after protein degradation?

• Lipids

• Nucleotides

• Small peptides

• Individual amino acids