Mutant nitrile hydratase, nucleic acid encoding mutant nitrile hydratase, vector and transformant containing nucleic acid, production method of mutant nitrile hydratase, and production method of amide compound

A mutant nitrile hydratase, being a nitrile hydratase having an α subunit with a sequence identity of 90% or more with respect to an amino acid sequence represented by SEQ ID NO:

• 1 and a β subunit with a sequence identity of 90% or more with respect to an amino acid sequence represented by SEQ ID NO:
• 2, the nitrile hydratase comprising at least one substitution of an amino acid residue selected from the group consisting of the following (a) to (q):
• (a) a substitution to Gly from Ala as an amino acid residue corresponding to a 23rd position from an N-terminus of SEQ ID NO:
• 1 in the α subunit;
• (b) a substitution to Met from Val as an amino acid residue corresponding to a 105th position from the N-terminus of SEQ ID NO:
• 1 in the α subunit;
• (c) a substitution to Cys from Leu as an amino acid residue corresponding to a 142th position from the N-terminus of SEQ ID NO:
• 1 in the α subunit;
• (d) a substitution to Asp from Glu as an amino acid residue corresponding to a 145th position from the N-terminus of SEQ ID NO:
• 1 in the α subunit;
• (e) a substitution to Gly from Pro as an amino acid residue at a 152nd position from the N-terminus of SEQ ID NO:
• 1 in the α subunit;
• (f) a substitution to Arg or Val from Pro as an amino acid residue corresponding to a 153rd position from the N-terminus of SEQ ID NO:
• 1 in the α subunit;
• (g) a substitution to Val from Gly as an amino acid residue corresponding to a 180th position from the N-terminus of SEQ ID NO:
• 1 in the α subunit;
• (h) a substitution to Leu from Glu as an amino acid residue corresponding to a 89th position from an N-terminus of SEQ ID NO:
• 2 in the β subunit;
• (i) a substitution to lie, Leu or Thr from Ala as an amino acid residue corresponding to a 122nd position from the N-terminus of SEQ ID NO:
• 2 in the β subunit;
• (j) a substitution to Gln from Thr as an amino acid residue corresponding to a 149th position from the N-terminus of SEQ ID NO:
• 2 in the β subunit;
• (k) a substitution to Val, Arg or Pro from Lys as an amino acid residue corresponding to a 153rd position from the N-terminus of SEQ ID NO:
• 2 in the β subunit;
• (l) a substitution to Ser from Cys as an amino acid residue corresponding to a 189th position from the N-terminus of SEQ ID NO:
• 2 in the β subunit;
• (m) a substitution to Pro, Ser or Gly from Glu as an amino acid residue corresponding to a 207th position from the N-terminus of SEQ ID NO:
• 2 in the β subunit;
• (n) a substitution to Trp, Ser, Pro, Phe, lie, Arg, Cys or Gly from Ala as an amino acid residue corresponding to a 232nd position from the N-terminus of SEQ ID NO:
• 2 in the β subunit;
• (o) a substitution to Glu or Gln from Ala as an amino acid residue corresponding to a 233rd position from the N-terminus of SEQ ID NO:
• 2 in the β subunit;
• (p) a substitution to Lys from Thr as an amino acid residue corresponding to a 188th position from the N-terminus of SEQ ID NO:
• 1 in the α subunit;
• and
• (q) a substitution to Gly from Glu as an amino acid residue corresponding to a 50th position from the N-terminus of SEQ ID NO:
• 2 in the β subunit.