33 results about "Chaperone Gene" patented technology

The invention relates to an unmarked gene-deleted and attenuated mutant strain of a vibrio alginolyticus wild strain, which is the attenuated active vaccine of the vibrio alginolyticus wild strain and in which the sRNA molecular chaperone gene hfq of the vibrio alginolyticus wild strain is deleted. The vibrio alginolyticus wild strain is EPGS020401, and the collection number of the vibrio alginolyticus wild strain is CCTCC NO.AB 209306. The invention also provides the preparation of the unmarked gene-deleted and attenuated mutant strain of the vibrio alginolyticus wild strain and the use thereof in prevention and control of vibrio alginolyticus disease in cultured fish. The unmarked gene-deleted and attenuated mutant strain of the vibrio alginolyticus wild strain or the preparation thereof, which are disclosed by the invention, eliminates universal potential environment and product safety risks of the conventional attenuated vaccine and is a safe, effective and economic vaccine for preventing and controlling vibrio alginolyticus diseases in cultured fish.

The invention discloses construction and an application of an astaxanthin synthesis strain. The invention provides a recombinant bacterium, which is prepared according to a method comprising the following steps of: expressing and synthesizing carotenoid related genes crtY gene, crtZ gene and crtW gene in escherichia coli, and regulating and controlling the expression of molecular chaperone genes groES and groEL in the escherichia coli to obtain the recombinant bacterium, according to the invention, the promoters with different intensities are utilized and gene copy is changed, so that coordinated expression among genes in a synthetic pathway of astaxanthin is realized, and the toxicity of metabolic intermediates is eliminated, so that the generation capacity of biosynthesis of astaxanthin is improved. In addition, stabilizing the expression of the exogenous gene and increasing the correct folding of the exogenous gene can also become an effective way for improving the biological activity of astaxanthin synthetic pathway enzyme and increasing the yield of astaxanthin.

The invention discloses a recombinant plasmid for production of oxalate decarboxylase, a system and a method for expressing escherichia coli, and application. The recombinant plasmid for production ofoxalate decarboxylase comprises an oxalate decarboxylase gene, a molecular chaperone gene and a gene for regulating and controlling intracellular manganese ion concentration. The recombinant plasmidis guided into an escherichia coli expression bacterial strain and the escherichia coli with MntP gene deletion to respectively obtain oxalate decarboxylase with solubility expression and activity; the culture temperature and induction temperature of the recombinant bacterial strain are optimized; when the culture temperature is 37 DEG C, and the induction temperature is 25 DEG C, the expression amount of the oxalate decarboxylase is higher; by utilizing the two steps of organic solvent precipitation and ammonia sulfate precipitation to simply purify, the specific activity of the oxalate decarboxylase can reach 45.6U / mg, and the activity is higher than 95%. By adopting the technical scheme, the recombinant plasmid has the advantages that the production and purifying technologies are simple; the expression amount and specific activity of the oxalate decarboxylase are higher, the industrialized amplification is easy, the cost is low, and the recombinant plasmid is suitable for the industrialized production and application of the oxalate decarboxylase.

To provide an activator of gene expression of molecular chaperone gene and applications thereof.This activator of gene expression of molecular chaperone gene contains an eggshell membrane component, for example, a powder containing eggshell membrane or a soluble eggshell membrane component. Moreover, the powder containing eggshell membrane used in the present invention may be a fine powder preferably having 6 μm or less in the mean volume particle diameter of the fine powder containing eggshell membranes, and / or 20 μm or less in the maximum volume particle diameter thereof, but not limited to these values.

The invention provides a method for improved high secretory production of proteins. The present invention addresses the problem of providing a production system which achieves, in a host cell such as yeast, high secretory production of proteins, particularly proteins having a complex structure such as an S-S bond and which is so safe as to obviate explosion-proof equipment and is suitable for industrial production. The present invention provides a transformed yeast obtained by introducing a chaperone gene and disrupting aox1 and / or protease genes, and a method for producing proteins using the transformed yeast.

The invention discloses a method preparing a recombinant human nerve growth factor by using an Escherichia coli expression system. Beta-subunit genes of the recombinant human nerve growth factor comprise 6 histidine purification sites, an enterokinase cleavage site and a beta-subunit gene encoding mature peptide of modified human nerve growth factor and a molecular chaperone gene. The beta-subunit genes of the recombinant human nerve growth factor have high expression quantity in the Escherichia coli; generated inclusion body protein has high-efficiency renaturation under the assist of the molecular chaperone; and the recombinant human nerve growth factor obtained by nickel column affinity chromatography after the molecular chaperone is cleavaged accurately by the enterokinase, has a purity greater than 99% and biological activity greater than 500,000 AU / mg.

The invention discloses the construction of an astaxanthin synthetic strain and its application. The invention provides a recombinant bacterium, which is prepared according to a method comprising the following steps: expressing the synthetic carotenoid-related genes crtY gene, crtZ gene and crtW gene in Escherichia coli, and regulating the expression of molecular chaperone genes groES and groEL in the Escherichia coli , the obtained recombinant bacteria; the present invention realizes the coordinated expression of genes in the astaxanthin synthesis pathway by using promoters of different strengths and changing the gene copy, eliminates the toxicity of metabolic intermediates, thereby increasing the production capacity of astaxanthin biosynthesis. In addition, stabilizing the expression of exogenous genes and increasing the correct folding of exogenous genes can also be an effective way to improve the biological activity of enzymes in the astaxanthin synthesis pathway and increase the production of astaxanthin.

The invention discloses a primer, a probe, a kit and a detection method for detecting fusion mutations of human ALK gene, and the primer and probe include: designing on the broken exon sequences of six partner genes in the ALK fusion gene Multiple upstream primers, shared downstream primers and fluorescent detection probes designed on ALK exon 20; 6 partner gene break exon sequences in ALK fusion gene include: EML4‑exon2 / 6 / 13 / 14 / 17 / 20, TFG ‑exon5, KIF5B‑exon15 / 17 / 24, TPR‑exon15, HIPI‑exon21, SEC31A‑exon21; the kit can cover up to 28 ALK fusion forms, with high specificity and sensitivity, and can effectively avoid false positives. The established one-step reverse transcription detection method can simplify operation and avoid contamination.

The invention discloses an Escherichia coli expression system for producing oxalate oxidase, a production method of oxalate oxidase and application thereof. The recombinant expression plasmid in the Escherichia coli expression system comprises: an oxalate oxidase gene, a molecular chaperone gene and a gene for promoting manganese ion pumping into Escherichia coli cell-related proteins. The present invention obtains the optimal expression of oxalate oxidase by screening and testing the genes and copy numbers of different manganese ion-related proteins, the type of promoters controlling the expression of molecular chaperones, and the type of medium used in the production process of oxalate oxidase Combined, the expression activity of oxalate oxidase in Escherichia coli exceeds 80U / mL. The specific activity of the oxalate oxidase preliminarily purified from the supernatant of the cell disruption liquid is greater than 20 U / mg, and the molecular weight of the monomer is about 25 kDa. The technical scheme of the invention has the advantages of simple production and purification process, high expression amount and specific activity, easy industrial scale-up, low cost, and favorable industrial production and application of this type of enzyme.

The invention discloses a genetically engineered bacterium expressing microorganism cholesterol esterase and a construction method thereof, and belongs to the technical field of enzyme engineering. The method comprises the steps that Burkholderia cepacia. source cholesterol esterase and cholesterol esterase molecular chaperone genes are connected in series to achieve coexpression, wherein cholesterol esterase genes and the molecular chaperone genes are connected through a SD sequence. According to the method, the Burkholderia cepacia. source cholesterol esterase is successively expressed, and active expression and efficient expression of the Burkholderia cepacia. source cholesterol esterase are achieved. The cholesterol esterase activity in a crude enzyme solution fermented by the constructed genetically engineered bacterium can reach 640 U / L.

The invention discloses an Escherichia coli expression system of recombinant protein containing manganese ions and an application method thereof. The recombinant expression plasmid in the Escherichia coli expression system is one of the following situations or a combination thereof: (1) at least comprising an Escherichia coli molecular chaperone gene and an enzyme protein gene containing manganese ions; (2) comprising an Escherichia coli molecular chaperone gene , enzyme protein genes containing manganese ions, and overexpression or inhibition of manganese ion channel-related protein genes; (3) including Escherichia coli molecular chaperone genes, enzyme protein genes containing manganese ions, and protein genes affecting intracellular manganese ion concentration . Through the construction and optimization of the Escherichia coli expression system, efficient soluble and active expression of the manganese ion-containing enzyme protein can be realized. Compared with the traditional method, the efficiency is high, the purification process is simple, and the cost is low, which is beneficial to the production of the manganese ion-containing enzyme. Industrial production and application.

The invention discloses a light-emitting reporting system. The light-emitting reporting system is constructed from a promoter fragment of molecular chaperone genes clpX, groE, dnaJ and dnaK, and a luxABCDE gene fragment connected with molecular chaperone gene promoters. The invention further discloses an application of the light-emitting reporting system to antibiotic recovering and screening. Compared with an existing antibiotic screening technique, the light-emitting reporting system disclosed by the invention has the advantages that the existence of antibiotics in an solution can be identified in a quick and high-flux manner, the discovering speed of new antibiotics can be increased, quick discovering and screening of the antibiotics can be realized, and the light-emitting reporting system has great application prospects.

The invention relates to the technical field of bioengineering, and particularly relates to an escherichia coli hydrotropic expression plasmid and a construction method and application thereof. According to the invention, the construction method of the hydrotropic expression plasmid comprises the following steps: (1) by taking streptomyces DNA as a template, amplifying to obtain partner genes groEL1, groES1 and groEL2; and (2) cloning the partner genes groEL1, groES1 and groEL2 to an escherichia coli plasmid vector pGro7 of which groEL and groES gene segments are deleted so as to obtain the hydrotropic expression plasmid pGroE. The pGroE plasmid disclosed by the invention and a dnmS and / or dnmQ gene coded glycosylated transferase are co-expressed; compared with the solubility of a pGro7 plasmid, the solubility of the pGroE plasmid can be remarkably improved; and the development of the hydrotropic expression plasmid provides a good solution for solving the inclusion body problem during gene expression.