Method for preparing inclusion body protein nanoparticles without fusion tag

Abstract

The invention relates to a method for preparing non-fusion-tag inclusion body protein nanoparticles. The method includes the following steps of firstly, fusing the end C of a spontaneous disruption protein intron with a target protein gene and fusing the end N of the spontaneous disruption protein intron with tag protein for enhancing target protein expression to obtain a fusion protein encoding gene; secondly, inducing the fusion protein encoding gene to be expressed on escherichia coli, and releasing target protein through spontaneous disruption of the end C of the spontaneous disruption protein intron to form inclusion body protein; thirdly, smashing and centrifuging escherichia coli cells, and removing supernate to obtain the non-fusion-tag inclusion body protein nanoparticles. By means of the method, target protein is removed on the level of nclusion body protein nanoparticles, the technical blank of preparing the non-fusion-tag inclusion body protein nanoparticles is filled in, the spontaneous disruption of the protein intron is completed in escherichia coli bodies, and post-treatment is simple.

Description

technical field [0001] The invention relates to the field of biotechnology, in particular to a method for preparing inclusion body protein nanoparticles without fusion tags. Background technique [0002] As a prokaryotic expression system for expressing foreign proteins, Escherichia coli is widely used due to the advantages of short cycle, low culture cost, simple operation, and high expression level. The key element of folding, resulting in some eukaryotic proteins or proteins that are toxic to cells cannot be expressed or the expression efficiency is very low. [0003] The usual solution for this type of protein is to express it in fusion with a fusion protein that can improve protein expression, but the fusion protein can easily lead to the presence of the target protein in the form of inclusion bodies while improving protein expression. Inclusion body proteins are often discarded as misfolded inactive products, and recent studies have shown that inclusion body proteins ...

AI Technical Summary

Problems solved by technology

[0004] However, inclusion body proteins containing fusion tags may limit their application in tissue engineering due to the body's immune response against fusion tags

For soluble expressed proteins, the target protein is usually purified first, and then the tag protein is removed in vitro through chemical methods, proteolytic digestion, and intein-based self-cleavage. For proteins expressed in the form of inclusion bodies, the inclusion body protein is also purified first, and then After the inclusion body protein is denatured and refolded, the label is removed by the above method, but this will not restore the nanostructure of the inclusion body protein

Therefore, there is currently no way to remove the fusion tag on the basis of maintaining the structure of the inclusion body protein nanoparticle, so as to prepare inclusion body nanoparticles without fusion tags

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