IMPROVED β-FRUCTOFURANOSIDASE

摘要

[Problem] To provide an improved β-fructofuranosidase which enables the production of kestose with high efficiency while reducing the amount of a by-product such as nystose produced during the production of kestose. [Solution] An improved β-fructofuranosidase comprising an amino acid sequence which is produced by introducing an amino acid mutation into an amino acid sequence for a β-fructofuranosidase having 60% or higher identity to the amino acid sequence for wild-type β-fructofuranosidase which is represented by SEQ ID NO: 2, wherein the amino acid mutation is such a mutation that, when amino acid sequence alignment is performed, a histidine (H) residue corresponding to the position-395 as numbered from the N-terminal of the amino acid sequence for the wild-type β-fructofuranosidase which is represented by SEQ ID NO: 2 can be replaced by an arginine (R) residue or a lysine (K) residue.