Omichi K, Nagura N, Ikenaka T
J Biochem. 1980 Feb;87(2):483-9. doi: 10.1093/oxfordjournals.jbchem.a132768.
The reactive of Streptomyces subtilisin inhibitor (SSI) was investigated by chymotryptic cleavage of the reactive site peptide bond and its resynthesis by inhibitor-subtilisin complex formation. The results show that the reactive site peptide bond of the inhibitor is Met(73)-Val(74) and that subtilisin specifically cleaved the Leu(6)-Tyr(7) bond of SSI upon complex formation.