Genetically engineered L-sorbose reductase-deficient mutants

摘要

The present invention provides a genetically engineered microorganism belonging to the genus Gluconobacter or Acetobacter, which has an engineered gene for the biological activity of reducing L-sorbose which is more than 90% non-functional in developing the said biological activity. The engineered microorganism is derived from a microorganism belonging to the genus Gluconobacter or Acetobacter, and has the biological activity for reducing L-sorbose that is less than 10% of the amount of the activity of the wild type organism. The present invention further provides a method for producing the genetically engineered microorganism by mutating the gene of a microorganism of the genus Gluconobacter or Acetobacter which encodes a protein having the L-sorbose reductase activity, determining the L-sorbose reductase activity of the resulting microorganism with the mutated gene and selecting the genetically engineered microorganism having L-sorbose reductase activity that is less than 10% of the amount of the activity of the wild type microorganism.