TABLE 1.

Splicing efficiencies of the Ssp DnaB wild type and improved inteins

^a Sites 1–10 are insertion sites in the KanR gene.

^b Native extein residues are shown in bold.

^c SI are additional residues added to APH(3′)-I.

^d Splicing efficiency is: −, <5%; +, 10–50%; ++, 51–80%; +++, >80%.

^e Highlighted boxes indicate the insertion sites at which each improved intein was evolved through directed evolution.