Fusion Bsu DNA polymerase and Bsu DNA polymerase mutant as well as genes, plasmids and genetically engineered bacteria of fusion Bsu DNA polymerase and Bsu DNA polymerase mutant

The invention provides a fused Bsu DNA polymerase and a Bsu DNA polymerase mutant as well as a gene, a plasmid and a genetically engineered bacterium thereof, and relates to the technical field of biology. The fusion Bsu DNA polymerase provided by the invention contains a Bsu DNA polymerase fragment and a protein fragment fused at the N end of the Bsu DNA polymerase fragment, and can be efficiently expressed in escherichia coli, and the expression purity can reach 95% or above. According to the Bsu DNA polymerase mutant provided by the invention, Aps at the 41st site of a Bsu DNA polymerase fragment in the fused Bsu DNA polymerase is mutated into Glu, Val at the 194th site of the fused Bsu DNA polymerase is mutated into Ala, 3 '-5' exonuclease activity is deleted, the Bsu DNA polymerase mutant can be efficiently expressed in escherichia coli, the expression purity can reach 97% or above, and the Bsu DNA polymerase mutant can interact with other related proteins to realize isothermal amplification. 本发明提供了一种融合B