Figure 2From: Recent advances in in vivo applications of intein-mediated protein splicingMechanism of protein splicing. X = S or O, such that residue 1 or the intein may be Cys or Ser, and residue C + 1 of the C-extein may be Cys, Ser or Thr. The finishing reaction shows the production of C-terminal Asn, but may also produce iso-Asn.Back to article page