(S)-HYDROXYNITRILE-LYASE HAVING IMPROVED SUBSTRATE RECEPTION AND ITS USE

PROBLEM TO BE SOLVED: To obtain the new subject lyase having improved substrate reception, and obtained by substituting an amino acid residue of an (S)-hydroxynitrile-lyase such as the one derived from Hevea brasiliensis, with an amino acid residue not larger than the amino acid residue. SOLUTION: This (S)-hydroxynitrile-lyase having improved substrate reception and derived from an (S)-hydroxynitrile-lyase of Hevea brasiliensis or Manihot esculenta is the new one obtained by substituting one or more large amino acid residues of the (S)-hydroxynitrile-lyase with an amino acid residue not larger than the amino acid residues. The enzyme is obtained by inducing mutation to a gene encoding the (S)-hydroxynitrile-lyase in a hydrophobic channel leading to an active center by using a kit for inducing the direct mutation to a quickly changing site, or the like, transducing the gene with the induced mutation into an expression vector, integrating the resultant expression vector to a host cell, and expressing the gene.