In a Protein Targeted for Destruction, Ubiquitin Is Most Commonly

Multiple Choice

In a protein targeted for destruction, ubiquitin is most commonly attached to a _____ residue, forming a/an ______ bond between ubiquitin and the targeted protein.

A) Ser; ester
B) Lys; amide
C) α-amine group of the N-terminal amino acid if the particular residue is Arg, Lys, His, Phe, Tyr, Trp, Leu, Asn, Gln, Asp or Glu; amide
D) Glu; acid anhydride
E) Cys; thioester