42 results about "GENE RE-ARRANGEMENTS" patented technology

The invention discloses a building method and application of a lactobacillus reuteri resistance-marker-free gene integration system. By means of the point mutation technology, a point mutation gene pheSM of a lactobacillus reuteri pheS gene is obtained, the point mutation gene pheSM and a erythromycin resistance gene are used for building an integrated framework LR-pheSM-em-RR, the integrated framework LR-pheSM-em-RR is electrically converted into L.renteri XNY competent cells, and pheSM genetic recombination lactobacillus L.renteri XNYM is obtained through erythromycin screening; then, the gene integration framework is constructed and inserted, then the gene integration framework is electrically converted into pheSM gene recombination lactobacillus reuteri competent cells, and the lactobacillus reuteri without resistance markers can be obtained through para-chlorophenylalanine acid resistance screening. According to the method, resistance genes are not introduced into host bacteria genomes, so that biological safety hidden hazards of the resistance genes and the polarity effect of the resistance genes on upstream genes and downstream genes are avoided. By means of the system, gene targeted integration can be carried out on the host bacteria for multiple times.

The invention discloses a triple label and method for simultaneously visualizing DNA, mRNA and protein of genes in living cells. The tag contains a CRISPR-Tag DNA sequence composed of 12 TS1 repeat units, an MS2 DNA sequence composed of 12 MS2V5 unit sequences, and a blue fluorescent protein sequence containing introns. The DNA sequence is short in length and can be inserted into the N-terminal or C-terminal of the target protein-coding gene through CRISPR-Cas9-mediated gene recombination; the preparation method first prepares the TriTag tag, constructs a visualized stable cell line, and then constructs the target endogenous gene visualization system and Transfection and sorting, and finally live cell dynamic imaging can be realized. The TriTag of the present invention can be marked to realize dynamic imaging of chromatin, and can intuitively visualize the chromatin dynamics and gene expression of endogenous specific target genes, which is conducive to data integration and analysis, and helps to analyze the dynamic regulation mechanism of gene expression .

The invention belongs to the technical field of genetic engineering, and in particular relates to a preparation method of a semaglutide precursor. The invention adopts gene recombination technology, and compared with chemical synthesis, the production of impurities is reduced, and the purity and yield are relatively high; The main steps include: firstly, using gene recombination technology, a plasmid with a GLP-1 (9-37) gene sequence and a tandem expression sequence is introduced into Escherichia coli (Escherichia coli) BL21 (DE3), and recombinant engineering bacteria are constructed. After high-density fermentation induction, the tandem expression protein expressing GLP-1(9-37) was obtained, and then the semaglutide precursor GLP-1(9-37) was obtained after steps such as denaturation, renaturation, enzyme digestion, and purification.

The invention discloses a conceptual design method based on product gene recombination technology, which can effectively improve the reuse rate of design knowledge, and discover the gene defect of the original product through the product gene recombination technology, and replace the defective gene with a good gene, Afterwards, through product gene expression, a variety of better product structure schemes are obtained. This method is of great significance for improving the quality and innovation of product design schemes.

The invention provides an anti-HIV-I polypeptide, a combination polypeptide, relative encoding sequences, expression carrier, a preparation method and application thereof, wherein the polypeptide and combination polypeptide are synthesized by gene recombination and expression or polypeptide synthesizer, with simple process, improved final yield, effect for inhibiting HIV-I intrusion, thus is suitable for industrial production.