The invention discloses a
sucrose phosphorylase
mutant, an
engineering bacterium and application of the
sucrose phosphorylase
mutant in catalytic synthesis of alpha-
arbutin. The
sucrose phosphorylase CbSP
mutant is obtained by performing site-saturation
mutation or combined
mutation on the 53rd site, the 60th site, the 135th site, the 196th site, the 197th site or the 234th site of an
amino acid sequence shown as SEQ ID No.3. The invention further discloses a preparation method of the
sucrose phosphorylase CbSP mutant. The catalytic activity and the
thermal stability of the mutant constructed by the invention are remarkably improved, the
specific enzyme activity of the
sucrose phosphorylase CbSPM2 mutant is improved by 47.39 times compared with that of a
wild type, the maximum substrate (
hydroquinone) feeding amount can reach 55g / L, the product concentration is gradually increased along with the extension of time, most substrates can be converted within 24h, the
molar conversion rate of the substrates is 90.23%, and the product concentration is 122.7 g / L. The CbSP mutant disclosed by the invention has a good industrial application prospect.