Abstract: Provided in the present invention is a method for preparing a constant-temperature amplification mixed enzyme system. Specifically, disclosed in the present invention is a method comprising: removing the vast majority of glycerol from a prepared glycerol-containing RPA enzyme system by means of dialysis, and then concentrating the enzyme system containing trace glycerol by using an ultrafiltration method. Experiments show that the amplification performance of an RPA mixed enzyme system prepared by means of such method is significantly improved.

Abstract: Provided are a Taq polymerase mutant, a preparation method therefor and the use thereof. The Taq polymerase mutant includes an amino acid sequence having at least 70% identity to the amino acid sequence shown in SEQ ID NO:2, wherein the amino acid sequence has mutations occurring at one or more positions selected from the group consisting of: P40, L125, G200, D335, G499, E634, F769 or a combination thereof. The provided Taq polymerase mutant has high amplification activity, can obtain more amplification products compared with wild-type Taq polymerase under the same number of PCR cycles, and moreover, is resistant to whole blood and high salt and has low 5?-3? exonuclease activity.

Abstract: The present invention provides a high temperature resistant reverse transcriptase mutant and its use. In particular, the present invention constructs a reverse transcriptase (M-MLV) mutant library, and the mutants with improved thermostability and higher amplification efficiency are finally screened out by stepwise screening. Under high temperature conditions, the reverse transcription efficiency of the reverse transcriptase mutant of the present invention is greatly improved compared to the wild type.