| abstract |
The invention relates to the field of genetic engineering, in particular to a method for improving the thermal stability of phytase, mutants and applications. The present invention carries out a series of mutations to the phytase, and these mutations may involve the introduction of disulfide bonds, the reduction of unfolding free energy, and the optimization of key residues in the co-evolution process, thereby significantly improving the thermal stability of the enzyme. The present invention mutates the phytase APPAmut4, and the phytase mutant is compared with the parent, and the phytase thermostability is enhanced, wherein the best mutant APPAmut9 still retains about 70% of the activity after being treated at 100 ° C for 5 min, The wild-type enzyme is already inactive. The invention overcomes the deficiencies of the prior art and provides a phytase mutant with high thermal stability and suitable for application in the fields of energy, food and feed. Therefore, the phytase mutant provided by the present invention can be well used in energy, food and feed industries, and has broad application prospects. |