Recombinant human-oocyte zona pellucida ZP3 protein and preparation method thereof

Abstract

The invention discloses recombinant human-oocyte zona pellucida ZP3 protein and a preparation method thereof. The nucleic acid sequence for encoding the recombinant human-oocyte zona pellucida ZP3 protein is shown in SEQ ID NO:1. The nucleic acid sequence for encoding the ZP3 protein is obtained by massive screening, is transformed by codon preference and eliminates secondary structures unbeneficial to expression. The obtained ZP3 sequence not only can guarantee that the primary structures are the same as a natural structure, but also can guarantee that the space structure is closer to the natural structure. The recombinant human-oocyte zona pellucida ZP3 protein and the preparation method disclosed by the invention have the advantages that the nucleic acid sequence for encoding the ZP3 protein is connected with sequences of phoA promoters and periplasmic secretory signal peptide StII, and the connected product is transferred into escherichia coli to construct and obtain ZP3 engineeredescherichia coli with high-efficiency and stable secretory expression. By high-density fermentation culture and high-low adjustment induction of the phosphorus concentration, ZP3 exists in periplasmin a soluble form. ZP3 is high in expression level and accounts for about 20% of the total protein of the thallus.

Description

technical field [0001] The invention belongs to the technical field of polypeptides, and in particular relates to a recombinant human egg cell zona pellucida ZP3 protein and a preparation method thereof. Background technique [0002] Zona pellucida (ZP) is a layer of extracellular matrix surrounding mammalian egg cells, which has tissue specificity. In the process of fertilization, the acrosome reaction occurs after the sperm recognizes and combines with it, penetrates the ZP, and fuses with the egg. The human zona pellucida is composed of 3 major glycoproteins (ZP1, ZP2 and ZP3). Among them, ZP3, as the primary receptor of sperm and the inducer of acrosome reaction, plays a key role in the fertilization process. [0003] ZP3 protein has strong antigenicity. Actively immunizing animals can induce the body to produce antibodies, which can interfere with the information exchange between eggs and follicle cells, and make eggs lose the ability to combine with the same kind of ...

AI Technical Summary

Problems solved by technology

Regardless of whether the protein exists in the form of soluble or inclusion bodies, it is expressed in the cytoplasm, and the bacteria must be broken by ultrasonic waves to release the protein, which not only destroys the protein itself, but also increases the difficulty and cost of purification.

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