Application of Diels-Alder reaction enzyme and preparation method and application of mutants thereof

The invention provides application of a Diels-Alder reaction enzyme and a preparation method and application of mutants thereof, and belongs to the technical field of genetic engineering. It is foundthat the Diels-Alder reaction enzyme with its amino acid sequence as shown in SEQ ID No.1 also can catalyze the synthesis of unnatural a D-A product besides catalyzing substrate synthesis of a natural D-A product; and it is further found that the substrate dienes of the D-A reaction enzyme also include biphenyls, flavonoids and benzofurans. The substrate application range of the D-A reaction enzyme is broadened, and the mutants of the enzyme are provided. It is found that those mutants also can catalyze substrate synthesis of natural or unnatural D-A products. The D-A reaction enzyme and itsmutants provided by the invention are helpful to the development and utilization of D-A products, and the possibility for the synthesis of other important chemical precursors or natural products containing hexatomic rings is provided.