Patent ID: 6876932
Filing Date: 2005-04-05
Classification: A21D,C12N

Abstract:
1. A method of constructing a variant of a parent maltogenic alpha-amylase, wherein said parent maltogenic alpha-amylase has an amino acid sequence which is at least 70% identical to amino acid residues 1-686 of SEQ ID NO:2, and wherein said parent maltogenic alpha-amylase has an active site which comprises a cluster of three amino acid residues corresponding to positions D329, D228 and E256 in SEQ ID NO:2, which method comprises: a) modeling the parent alpha-amylase on the three-dimensional structure of amino acid residues 1-686 of SEQ ID NO:2 depicted in the Appendix to produce a three-dimensional structure of the parent alpha-amylase; b) identifying in said three-dimensional structure of the parent alpha-amylase an amino acid residue which (i) is within 15 Å of one of said three amino acid residues and (ii) is involved in electrostatic or hydrophobic interactions with an active site residue: and c) constructing the variant by substituting the amino acid residue identified in said b) with another amino add residue which changes the electrostatic and/or hydrophobic surroundings of said active site residue wherein the variant has maltogenic alpha-amylase activity.