T7 RNA polymerase mutant with high thermal stability and application thereof

The invention discloses a T7RNA polymerase mutant with high thermal stability and application of the T7RNA polymerase mutant, and relates to the technical field of biology, the T7RNA polymerase mutant comprises mutants C125A, C216L, Q269M, C347L, M401K, W422F, Y457L, G464M, A468F, F481W, Q505A, C510E, C515P, V567P, V687E, M696A, A703T, H772K, P780K, R792M, H799G, K801G, E830G, C839N, P865L or/and A881F; and the amino acid sequences of the amino acid sequences are respectively shown as SEQ ID NO.3 to SEQ ID NO.28. The invention discloses a mutation site selection method, a mutation site expression method, a melting temperature measurement method and an activity measurement method. The mutant can be subjected to transcription reaction at high temperature so as to reduce by-products generated in preparation of mRNA vaccines and drugs and is suitable for a nucleic acid isothermal amplification technology. According to the invention, mutation sites of amino acids are predicted by using deep learning, the thermal s