Compound enzyme and application thereof

The invention relates to synthetic biology, in particular to a compound enzyme and application thereof. The compound enzyme comprises: (1) a double-stranded RNA ligase; (2) a protein with substrate affinity, wherein the protein is selected from one or more of a DNA double-chain binding domain, an RNA/DNA composite chain binding domain, a single-chain DNA covalent binding protein or a dsRNA binding protein; one or more proteins with substrate affinity are connected to the N end and/or C end of the double-stranded RNA ligase through a first fusion protein linker; the substrate is a first single-stranded RNA fragment, a second single-stranded RNA fragment and splint oligonucleotide. According to the compound enzyme provided by the invention, the ligation efficiency can be improved to 80-90% or even higher and is far higher than that of common RNA ligation enzymes. 本发明涉及合成生物学，具体涉及一种复合酶及其应用。所述复合酶包括：(1)双链RNA连接酶；(2)具有底物亲和性的蛋白，所述蛋白选自DNA双链结合结构域、RNA/DNA复合链结合结构域、单链DNA共价结合蛋白、或者dsRNA结合蛋白中的一种或多种；一个或多个所述具有底物亲和性的蛋白通过第一融合蛋白接头