Lecture 18 : Proteolysis Flashcards
1
Q
What is proteolysis?
A
Breakdown of proteins into polypeptides or amino acids via enzymic cleavage of peptide bonds
2
Q
What is the 26S proteasome
A
Protein complex which degrades proteins into smaller polypeptides via ubiquitin-mediated proteolysis
3
Q
When does proteolysis happen
A
- Regulate protein synthesis
- Targeting misfolded damaged proteins
- Recycling proteins / amino acids
4
Q
What is ubiquitin
A
- 76 amino acid polypeptide
- Covalently bonded at its C terminal glycine-76 to a lysine in the target protein or another ubiquitin molecule to form polyubiquitin chains
- Called ubiquitylation or ubiquitination
5
Q
learn ubiquitin shit
A
6
Q
Structure of 26S Proteosome
A
7
Q
20s Proteasome Core
A
- Barrel shaped symmetrical structure
- Proteolysis happens in central channel
8
Q
Role of ubiquitin-proteasome pathway
A
- Cell growth in cell cycle
- DNA damage and repair
- Transcription
- Metabolism
9
Q
A
