Polypeptide tag and application thereof in in vitro protein synthesis

Abstract

Provided is a polypeptide tag. The amino acid sequence of the polypeptide tag is Xaa1Xaa2Xaa3PHDYNXaa4Xaa5Xaa6 (SEQ ID NO: 37), wherein in the formula, Xaa1, Xaa2, Xaa3, Xaa4, Xaa5, and Xaa6 are each independently an amino acid or none. The polypeptide tag is used for labeling a target protein. In a second aspect, provided is a polypeptide fusion protein, comprising the following two structures: (1) any polypeptide tag according to the first aspect, and (2) a target protein connected to the polypeptide tag. Also provided are an in vitro cell-free protein synthesis system and an application thereof in in vitro protein synthesis. By constructing the polypeptide tag and a target protein as a fusion protein, the expression of the labeled target protein can be effectively increased without removing the polypeptide tag.

Dependencies are inferred from the claim text.