samp1, Small archaeal modifier protein 1
Also Known as
Functions as a protein modifier covalently attached to lysine residues of substrate proteins, as well as a sulfur carrier in molybdenum cofactor (MoCo) biosynthesis. The protein modification process is termed sampylation and involves the formation of an isopeptide bond between the SAMP1 C-terminal glycine carboxylate and the epsilon-amino group of lysine residues on target proteins. May serve as a proteolytic signal in the cell to target proteins for degradation by proteasomes.