46 results about "Catalase Gene" patented technology

The invention discloses a method by using a co-expression recombinant bacteria strain to convert and product alpha-ketoglutarate, and belongs to the technical field of biology. The method is characterized in that novel L-glutamic oxidase is screened from streptomycete and is induced to express and purify in escherichia coli, and the enzymatic property is studied; when the pH (potential of hydrogen) value is 5.5 to 7.0, the enzyme has higher activity, the most suitable reaction temperature is 30 to 45 DEG C, Vmax is 100 to 150U / mg, and Km is 8 to 10mM; the original gene sequence of the L-glutamic oxidase is subject to codon optimization, and the plasmid co-expression with a catalase gene from the escherichia coli is performed, so as to construct the co-expression recombinant bacteria strain; the recombinant bacteria strain is used as a whole-cell catalyst to convert the L-glutamic acid (salt), the output of alpha-ketoglutarate reaches 76.08g / L after reacting for 9h, and the molar conversion rate is 96.8%. The method has the advantages that the problems of complicated production steps, low yield, pollution to environment and the like in the alpha-ketoglutarate production process aresolved, the high-yield and one-step type production of the alpha-ketoglutarate is realized, and the industrial application value is higher.

The invention relates to a novel-originated catalase and the construction of recombinant engineering strains of the catalase. The construction is characterized in that primers are designed according to a catalase gene of bacillus pumilus for the first time, and recombinant expression vectors are constructed; the vectors are converted to genetic engineering strains, i.e., Escherichia coli and Bacillus subtilis for heterologous expression; the recombinant engineering strains are subjected to fermented cultivation through a 5L fermentation tank by using a fermentation culture medium, wherein catalase of recombinant Escherichia coli is mainly subjected to intracellular expression and has the enzyme activity of 6645U / mL, catalase of recombinant B. subtilis 168 has the total enzyme activity of 23,263U / mL and the extracellular enzyme activity of 15,368U / mL, catalase of B. subtilis WB600 has the total enzyme activity of 26,635U / mL and the extracellular enzyme activity of 20,128U / mL, the extracellular synthesis of the catalase is better facilitated by using the B. subtilis WB600 as a host, and thus the B. subtilis WB600 has an important industrial application value. The invention achieves the maximum yield compared with currently-reported methods which are used for producing the catalase by using microbes, so that a practical and effective policy for industrial production of the catalase is provided.

The present invention relates to a gene encoding a catalase and use thereof, in particular, a brewery yeast having high sulfite-producing capability, alcoholic beverages produced with said yeast, and a method for producing said beverages. More particularly, the present invention relates to a yeast, whose capability of producing sulfite, that contribute to stability of flavor in products, is enhanced by amplifying expression level of CTT1 gene encoding a catalase Ctt1p, especially non-ScCTT1 gene or ScCTT1 gene specific to a lager brewing yeast, and to a method for producing alcoholic beverages with said yeast.

The invention relates to a recombinant lactobacillus rhamnosus engineering strain and a preparation method thereof. The lactobacillus rhamnosus engineering strain carries expression vectors of a catalase gene and a superoxide dismutase gene which are connected in series. The method for preparing the engineering strain comprises the following steps of: 1) amplifying catalase gene segments and superoxide dismutase gene segments from genomes of lactobacillus sake and streptococcus thermophiles by a polymerase chain reaction (PCR) method; 2) designing a specific restriction enzyme site, wherein the restriction enzyme site is connected in series with an escherichia coli-lactobacillus shuttle plasmid vector pSIP502; and 3) transforming a recombinant plasmid into lactobacillus rhamnosus by an electroporation method. The recombinant lactobacillus rhamnosus engineering strain prepared by the method can remarkably enhance oxidation resistance and can be applied to the fermented food industry.

The invention relates to a recombinant lactobacillus casei engineering strain and a preparation method thereof. The lactobacillus casei engineering strain carries an expression vector of a catalase gene and a bile salt hydrolase gene which are connected in series. The preparation method of the engineering strain comprises the following steps of: 1) respectively amplifying segments of the catalase gene and the bile salt hydrolase gene in genomes of lactobacillus sake and lactobacillus plantarum by a PCR method; 2) designing a specific restriction enzyme cutting site and constructing the specific restriction enzyme cutting site in an Escherichia coli-lactobacillus shuttle plasmid vector pSIP502 by series connection; and 3) converting a recombinant plasmid to lactobacillus casei by an electroporation method. The recombinant lactobacillus casei engineering strain prepared by the method can obviously improve oxidation resistance and bile salt resistance and can be applied to the fermented food industry.

The present invention belongs to the field of biotechnology, and is especially process of preparing recombinant humanized catalase. The process of obtaining humanized catalase in high yield includes cloning humanized catalase gene by means of gene engineering technology, constructing its expression plasmid and transforming to cell. The process is simple and has no disease contamination and high yield of humanized catalase, and the prepared humanized catalase has high activity. The present invention includes also the new recombinant plasmid and transformant. Experiments show that the expressed recombinant humanized catalase may be applied in preparing medicine for resisting infection, resisting oxidation, resisting senility and antagonizing tumor.

The invention relates to a novel-originated catalase and the construction of recombinant engineering strains of the catalase. The construction is characterized in that primers are designed according to a catalase gene of bacillus pumilus for the first time, and recombinant expression vectors are constructed; the vectors are converted to genetic engineering strains, i.e., Escherichia coli and Bacillus subtilis for heterologous expression; the recombinant engineering strains are subjected to fermented cultivation through a 5L fermentation tank by using a fermentation culture medium, wherein catalase of recombinant Escherichia coli is mainly subjected to intracellular expression and has the enzyme activity of 6645U / mL, catalase of recombinant B. subtilis 168 has the total enzyme activity of 23,263U / mL and the extracellular enzyme activity of 15,368U / mL, catalase of B. subtilis WB600 has the total enzyme activity of 26,635U / mL and the extracellular enzyme activity of 20,128U / mL, the extracellular synthesis of the catalase is better facilitated by using the B. subtilis WB600 as a host, and thus the B. subtilis WB600 has an important industrial application value. The invention achieves the maximum yield compared with currently-reported methods which are used for producing the catalase by using microbes, so that a practical and effective policy for industrial production of the catalase is provided.

The invention belongs to the field of genetic engineering, and relates to a method for improving the enzyme activity of heterologous expression of L-amino acid deaminase, which uses L-amino acid deaminase (L-amino acid deaminase, LAAD) gene and catalase (Catalase) Gene expression in tandem. The present invention adopts L-amino acid deaminase to be expressed in series with catalase, which increases the enzyme activity per unit cell and increases the amount of cell per unit fermentation volume, thereby having high industrial application value.

The invention relates to a method for detecting the diversity of bacterial catalase in seawater by using degenerate primers, designing a combination of four kinds of degenerate primers based on the conserved region of bacterial catalase, and using polymerase chain reaction to amplify the diversity of bacterial catalase in seawater. Catalase gene fragments, and then use Escherichia coli to construct a library of enzyme gene fragments, use restriction endonucleases to digest the enzyme genes in the library, detect the molecular weight distribution of the fragments by electrophoresis, and determine the types of different electrophoresis bands, and finally Different types of catalase genes were sequenced separately to obtain information on the diversity of catalase genes. This method is an accurate, reliable, rapid, new method using degenerate primers to detect the diversity of bacterial catalase in seawater, and can be used to detect the diversity of bacterial catalase in seawater.

The invention discloses low-temperature catalase, its preparation method and application. The present invention separates the catalase gene from the Tianshan soil macrogene, and its polynucleotide sequence is shown in SEQ ID No.1, encoding 502 amino acids and a stop codon. The optimal temperature of the catalase of the present invention is 10-20°C, and it has high enzyme activity in the low temperature range of 0-30°C, has the characteristics of a low-temperature enzyme, and can play a role in removing H in a low-temperature environment. 2 o 2 role. The catalase of the present invention has good thermal stability, and has good thermal stability at 40°C. After 3 h of treatment, 74% of the enzyme activity still remains, and has certain thermal stability at 50°C. After 0.5 h of treatment 78% of the enzyme activity still remained. The optimal pH of the catalase of the present invention is 8.0. The present invention further provides the catalase as an antioxidant in removing H 2 o 2 in the application.

The present invention relates to a gene encoding a catalase and use thereof, in particular, a brewery yeast having high sulfite-producing capability, alcoholic beverages produced with said yeast, and a method for producing said beverages. More particularly, the present invention relates to a yeast, whose capability of producing sulfite, that contribute to stability of flavor in products, is enhanced by amplifying expression level of CTA1 gene encoding a catalase Cta1p, especially non-ScCTA1 gene or ScCTA1 gene specific to a lager brewing yeast, and to a method for producing alcoholic beverages with said yeast.

The invention discloses a method for transforming and producing α-ketoglutarate by using a co-expression recombinant strain, and belongs to the field of biotechnology. The present invention selects a new type of L-glutamate oxidase from Streptomyces, induces expression and purifies it in Escherichia coli, and conducts enzymatic properties research. The optimum reaction temperature is 30~45℃, V max 100~150 U / mg, K m 8~10 mM. The original gene sequence of L-glutamate oxidase was codon-optimized and co-expressed with the catalase gene derived from Escherichia coli to construct a co-expression recombinant strain. The recombinant strain was used as the whole cell catalyst to convert L-glutamic acid (salt), and the yield of α-ketoglutarate reached 76.08 g / L after 9 h of reaction, and the molar conversion rate was 96.8%. The invention solves the problems of cumbersome production steps, low yield and environmental pollution of α-ketoglutaric acid, realizes high-yield and one-step production of α-ketoglutaric acid, and has high industrial application value.

The present invention relates to a novel signal sequence for mass-expression of catalase and a use thereof and, more specifically, to a novel lipase signal sequence; an expression vector comprising the signal sequence and a catalase gene; a recombinant microorganism into which the expression vector is introduced; and a method for mass-producing catalase by culturing the recombinant microorganism. The use of the expression vector comprising the novel signal sequence, according to the present invention, can induce mass expression and secretion of particular catalase and other target proteins, and thus the expression vector is very useful in the stable mass production of the particular catalase and other target proteins.

The invention relates to a recombinant lactobacillus rhamnosus engineering strain and a preparation method thereof. The lactobacillus rhamnosus engineering strain carries expression vectors of a catalase gene and a superoxide dismutase gene which are connected in series. The method for preparing the engineering strain comprises the following steps of: 1) amplifying catalase gene segments and superoxide dismutase gene segments from genomes of lactobacillus sake and streptococcus thermophiles by a polymerase chain reaction (PCR) method; 2) designing a specific restriction enzyme site, wherein the restriction enzyme site is connected in series with an escherichia coli-lactobacillus shuttle plasmid vector pSIP502; and 3) transforming a recombinant plasmid into lactobacillus rhamnosus by an electroporation method. The recombinant lactobacillus rhamnosus engineering strain prepared by the method can remarkably enhance oxidation resistance and can be applied to the fermented food industry.

The design of the invention relates to selection, detection and application of tagging single nucleotide polymorphic sites of a catalase (CAT) gene, and further relates to a haplotype consisting of the tagging single nucleotide polymorphic (SNP) sites of the CAT gene, a detection method of the haplotype and a kit for detecting the tagging single nucleotide polymorphic sites of the CAT gene. According to the selection, detection and application disclosed by the invention, 6 tagging SNP sites of the CAT gene related to noise-induced deafness are screened, wherein risk of an individual carrying an rs769217 site C allelic gene and suffering from the noise-induced deafness is greatly increased when noise intensity is 85-92dB, and risk of an individual carrying an rs208679 site A allelic gene and suffering from the noise-induced deafness is greatly increased when noise intensity is less than 85dB; a specific combined haplotype A-G-T-C-A-C individual carrying six tagging SNP sites, compared to other haplotype individuals, is higher in risk of suffering from the noise-induced deafness.