HEAT RESISTING LIPASE AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To obtain the subject new lipase having excellent heat resistance by replacing an amino acid in an amino acid sequence constituting an α-helix of a natural type lipase with another amino acid. SOLUTION: In a new heat resisting lipase, an amino acid in an amino acid sequence constituting α-helix is replaced with another amino acid, wherein the α-helix-constituting amino acid sequence begins from the proline of the 306 and ends at the threonine of the 315 in an amino acid sequence of a lipase expressed by the formula. The replacement enables the improvement of the heat resistance and the productivity per the use of the lipase. Further, the obtained lipase enables an esterification or a transesterification using a substrate having a high melting point on an industrial scale. The heat resisting lipase is obtained by isolating DNAs coding for the Rhizopus-derived lipase expressed by the formula from Rhizopus niveus, applying a site-specific mutation on the part of DNAs coding for the amino acids from the 306 to the 315 in the amino acid sequence and subsequently expressing the gene in a host cell.