Acid phosphatase mutant, use thereof and method for preparing nicotinamide riboside by same

A method for preparing nicotinamide riboside, wherein the method comprises:

• catalyzing nicotinamide mononucleotide in the presence of an acid phosphatase, KCl and anhydrous MgCl2 to convert nicotinamide mononucleotide into nicotinamide riboside, wherein the acid phosphatase comprises the amino acid sequence of SEQ ID NO:
• 2 or comprises an acid phosphatase mutant, wherein the acid phosphatase mutant is selected from (a), (b), or (c):
• (a) an acid phosphatase mutant comprising the amino acid sequence of SEQ ID NO:
• 3;
• (b) an acid phosphatase mutant comprising the amino acid sequence of SEQ ID NO:
• 2 with the exception of a mutation or mutations selected from the group consisting of D206I, K115I, K115F, S240E, K44C, K115I/S240E, K115F/K44C/D206I, and K115I/S240E/D206I;
• or
• (c) an acid phosphatase mutant having a catalytic activity higher than a catalytic activity of the acid phosphatase of the amino acid sequence of SEQ ID NO:
• 2, wherein the acid phosphatase mutant defined by (c) has 90% or more sequence homology with the amino acid sequence of the acid phosphatase mutant defined by (a) or (b), and wherein the acid phosphatase mutant defined by (c) uses nicotinamide mononucleotide as a substrate.