Metabolic regulation 4 Flashcards
1
Q
Enzyme regulation
A
Ubiquitin can be attatched to other proteins.
It is binded covalently to target proteins by the frmation of an isopeptide bond between the c terminal COOH group of ubiquitin and an epsilon amino on a lysine residue
2
Q
Ubiquitin conjugation
A
3 enzymes
Ezyme E1, release PPi, adds AMP to ubiquitin
Enzyme E1 cleaves the AMP, attatches itself
E2 enzyme substitutes itself for E1
E3 binds to the E2 ubiquitin complex,
E2 and E3 dissociates itself
E3 defines the specificity of ubiquitin.
3
Q
Ubiquitin has lysine residues
A
Hence the lysine themselves can be ubiquinated. Therefore ubiquitin can be further ubiquinated.
Polyubiquination form.
Can be linear or branched.
