48 results about "Decarboxylase activity" patented technology

The present invention concerns a new method for the biological preparation of a diol comprising culturing a microorganism genetically modified for the bioproduction of an aliphatic diol, wherein the microorganism comprises a metabolic pathway for the decarboxylation of a hydroxy-2-keto-aliphatic acid metabolite with an enzyme having a 2-keto acid decarboxylase activity, the product obtained from said decarboxylation step being further reduced into the corresponding aliphatic diol, and wherein the microorganism is genetically modified for the improved production of said hydroxy-2-keto-aliphatic acid metabolite.

The invention also concerns a modified microorganism for the production of an aliphatic diol.

The invention discloses a fermentation agent and the application method for processing low histamine salami sausage, comprising the followings: 1. The selected strains of fermentation agent are CGMCCNo.1923-pediococcus pentosaceus and CGMCCNo.1572-staphylococcus xylosus both without decarboxylase activity; 2. The matching proportion between the CGMCCNo.1923-pediococcus pentosaceus and the CGMCCNo.1572-staphylococcus xylosus is 1:1; 3. The fermentation agent dosage of the pediococcus pentosaceus and the staphylococcus xylosus are 100kg respectively every 100g of mince when processing, the inoculated-pathogen quantity can be up to 1 x 10<7>cfu/g. The adding method is as follow: to make fermentation liquid by mixing the pediococcus pentosaceus fermentation agent and the staphylococcus xylosus fermentation agent with equal ratio and being dissolved in 500g water, spread the fermentation liquid uniformly on the mix mince surface, and mix the mince and the fermentation liquid thoroughly; 4. The preserved preparation used is as follow: the mass ratio to the material mince is salt 3.0%, glucose 1.5%, sodium nitrite 0.015%, and ascorbic acid 0.08%; 5. Using the fermentation agent, preserved preparation and processing technology, the histamine content of salami product is reduced by more than 40% and meets with the food histamine content limitation requirement of the European Union. The invention is tested according to the regulated hygienic standards of cured meat products in the GB2730-2005 hygienic standard for cured meat products, the hygienic state of products meets with the standard, the product flavor and the hygienic safety are better than the traditional technologic product evidently. The invention has the advantages of good application prospect in the aspects of quality improvement and new product development of salami products.

A topical composition and method for its use for reducing sagging or wrinkles in the neck area of human skin. The composition includes safe and effective amounts of a mild topical astringent (such as Camphor) for skin tightening, a topical antispasmodic (such as benzaldehyde or benzyl cinnamate) for skin smoothing, and a topical skin irritant to increase localized skin circulation. The composition can also optionally include palmitoyl oligiopeptides to stimulate production of collagen and elastin in skin, a mushroom or plant leaf ferment extract to increase the cell turnover rate skin, and to increase hydration, skin firmness and elimination of fine facial lines, a cocao ferment extract to inhibit lipid peroxidation, inhibit excess ornithine decarboxylase activity, and stimulate cutaneous blood flow to reduce lines and wrinkles, and a Lactobacillus lysate extract to stimulate collagen production. These ingredients are mixed in a dermatologically acceptable carrier for topical application.

The present invention relates to nucleotide sequences encoding polypeptides with cis-aconitic decarboxylase activity, the cells transformed with such nucleotide sequences, preferably fungal or plant cells, and to methods wherein such transformed cells are use for the production of itaconic acid.

The present invention is directed to mutants of lysine decarboxylase, nucleic acids encoding the mutants, and vaccines comprising the mutants for inhibiting and reducing the development of periodontal diseases, including gingivitis and chronic periodontitis. The vaccine composition comprises a recombinant lysine decarboxylase mutant which is based on a native version of the enzyme from E. corrodens and induces production of antibodies that inhibit the activity of the lysine decarboxylase enzyme in the oral cavity. The recombinant lysine decarboxylase mutant, in one version, comprises a mutation at residue 365 or at other locations within the active site, and in a preferred embodiment is produced from E. coli in large amounts and to form inclusion bodies. The purified inclusion bodies can then be used in the vaccine composition to induce in vivo production of antibodies that inhibit the activity of native E. corrodens lysine decarboxylase.

The invention discloses an efficient production method of gamma-aminobutyric acid, and belongs to the field of fermentation engineering. In the provided method, a twin-arginine signal peptide gene (torA) and a glutamic acid decarboxylase gene (gadB) are fused and transferred to a escherichia coil BL21(DE3) host so as to obtain a recombinant bacterium pET20b(+)-torA-gadB/E.coli BL21(DE3) that can secret and express glutamic acid decarboxylase. The extracellular glutamic acid decarboxylase activity level of the recombinant bacterium in a shaking bottle can reach 5.11 U/mL, and 15.82 U/mL in a fermentation tank. By using the system and a substrate (sodium glutamate monohydrate), the output of gamma-aminobutyric acid can reach 203.7 g/L.

The present invention relates to recombinant microorganisms comprising an isobutanol producing metabolic pathway and methods of using said recombinant microorganisms to produce isobutanol. In various aspects of the invention, the recombinant microorganisms may comprise at least one nucleic acid molecule encoding a polypeptide with keto-isovalerate decarboxylase (KIVD) activity, wherein said polypeptide is at least about 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a polypeptide selected from SEQ ID NOs: 1-214. Also provided are modified decarboxylases exhibiting an improved ability to utilize α-ketoisovalerate as a substrate in various beneficial enzymatic conversions.

A method for detecting amino acid decarboxylase activity of spoilage bacteria in food belongs to the technical field of agricultural products. First, spoilage bacteria are isolated from food, fermented to obtain strain fermentation liquid, and then inoculated into a liquid medium containing amino acids to obtain biogenic amine detection. Use the spoilage bacteria fermentation liquid, and then obtain the supernatant of the sterile body by centrifugation, add Na2HPO4, NaOH and dansyl chloride to the supernatant and the mixed standard solution of biogenic amines, and obtain the derivatives of spoilage bacteria biogenic amines in a water bath under dark conditions. Derivative samples of samples and standard biogenic amines; after pointing and drying, put them into the development tank, wait for the developer to expand to 17cm from the sample point, take them out and dry them, then use automatic gel imaging analysis under ultraviolet light to take pictures respectively, and compare them Yes, determine the type of biogenic amine in the sample according to the Rf value, and judge the amino acid decarboxylase activity of the strain. The invention is convenient and quick, has low cost and can accurately realize the qualitative detection of biogenic amine.

The present invention concerns a microorganism genetically modified for the bioproduction of 1,3-propanediol from sucrose, wherein the microorganism comprises: a two-step metabolic pathway for the production of 1,3-propanediol, comprising a first step of decarboxylation of 4-hydroxy-2-ketobutyrate with an enzyme having a 2-keto acid decarboxylase activity, and a second step of reduction of the obtained 3 -hydroxypropionaldehyde with an enzyme having hydroxy aldehyde reductase activity, and genes enabling the microorganism to utilize sucrose as sole carbon source. The invention also concerns a new method for the biological preparation of 1,3-propanediol by fermentation, comprising cultivating said microorganism genetically modified, wherein the culture is performed in an appropriate medium comprising a source of sucrose, and recovering the 1,3 -propanediol being produced. In a preferred aspect of the invention, the source of sucrose is obtained from plant biomass.

An in vivo method for the production of pHS via a recombinant host cell is disclosed. The host cell expresses at least one gene encoding a polypeptide having para-hydroxycinnamic acid decarboxylase activity in combination with either at least one gene encoding a polypeptide having tyrosine ammonia lyase activity or at least one gene encoding a polypeptide having phenylalanine ammonia lyase activity.

The invention relates to a method for increasing the activity of enterococcus faecium Glutamate Decarboxylase by using D101 macroporous adsorption resin, and belongs to the technical field of biology. According to the method disclosed by the invention, the D101 microporous adsorption resin is used as an enzyme activity accelerator of enterococcus faecium GAD, and a D101 microporous adsorption resin-GAD composite catalytic system is constructed according to a proportion that the mass of the D101 macroporous adsorption resin to the volume of a substrate solution to the volume of an enterococcus faecium bacterial suspension solution or a GAD free enzyme solution is 1 to 1 to 1; when the D101 microporous adsorption resin-GAD composite catalytic system is subjected to reaction in a water bath oscillator of which the temperature is 37 to 43 DEG C at 80r/min or stirring reaction in a stirring tank at a low speed for 24 to 36 hours, the yield of GABA (Gamma-Aminobutyric Acid) can be increased by 18.54 to 149.11 percent; the D101 macroporous adsorption resin is capable of remarkably increasing the activity of the GAD, an exchange adsorption function of the D101 microporous adsorption resin on the GABA is also a purifying process of the GABA, a downstream extracting and purifying technology is simplified, and the production cost is reduced; the method is simple, green and environment-friendly.

A Corynebacterium glutamicum transformant having the capability of producing isobutanol and the following genes (1) to (5):

• (1) a gene which encodes an enzyme having acetohydroxy acid synthase activity;
• (2) a gene which encodes an enzyme having acetohydroxy acid isomeroreductase activity;
• (3) a gene which encodes an enzyme having dihydroxy acid dehydratase activity;
• (4) a gene which encodes an enzyme having 2-keto acid decarboxylase activity; and
• (5) a gene which encodes an enzyme having alcohol dehydrogenase activity,

at least one of the genes being endogenous, and at least one of the genes being exogenous, efficiently produces isobutanol.

The present invention relates to biocatalysts catalyzing the formation of α-olefins. In particular, the invention provides polypeptides with improved decarboxylase activity on C₁₀-C₁₆ free fatty acids, more particularly on C₁₀ or C₁₂ free fatty acids, as compared to the P450 fatty acid decarboxylase isolated from the Staphylococcus massiliensis strain S46 (Sm46). The invention further provides recombinant nucleic acids and vectors comprising the coding sequences encoding these polypeptides, genetically engineered host cells expressing said polypeptides and methods for the production of C₉-C₁₅ α-olefins, more particularly C₉ or C₁₁ α-olefins, using said polypeptides or said host cells.

The invention specifically relates to a method for preparing beta-alanine from maleic acid through multi-enzyme coupling, belonging to the field of biotechnology. The method comprises the following steps: adjusting the pH value of an aqueous maleic acid solution with a certain concentration to 6 to 9 by using ammonia water; then separately adding bacterial cells respectively with maleate isomerase activity, aspartase activity and aspartate-alpha-decarboxylase activity or crude liquid of the three enzymes; carrying out enzymatic reaction at 30 to 50 DEG C; and separating and converting products by using isoelectric-point crystallization or a combination of isoelectric-point crystallization and ion exchange resin so as to obtain high-purity beta-alanine. The method provided by the invention uses maleic acid as a substrate for preparation of beta-alanine via multi-enzyme coupling and has the advantages of wide sources of raw materials, low price, simple operation, low production cost, suitability for large-scale industrial production, etc.

The invention relates to a method for controlling the content of histamine in aquatic products. The washed aquatic products are immersed in a treating fluid, fished out, drained, put into an insulating bag for high-voltage pulsed electric field treatment, added to a fermentation container and fermented at the controlled temperature of 23 DEG C for 20-35 days; the aquatic products are collected, packaged and put into freezing storage. Histamine produced in the transportation and storage processes of the aquatic products can be remarkably reduced while the specific texture and nutritional ingredients of the aquatic products are retained, growth and metabolism of bacterium colonies producing amino acid decarboxylase activity in the processing process of the aquatic products can be inhibited or prevented better, generation of amino acid decarboxylase is prevented fundamentally, accordingly, generation of histamine is prevented in the whole processing process and is further controlled, and the method has great social and economic benefits.

The invention relates to a method for improving activity of enterococcus faecium glutamate decarboxylase by virtue of 732 cation exchange resin, and belongs to the field of bio-technology. According to the method provided by the invention, the 732 cation exchange resin is taken as an enzyme activity accelerant of the enterococcus faecium glutamate decarboxylase; a 732 cation exchange resin-glutamate decarboxylase composite catalysis system is constructed by mixing the 732 cation exchange resin, an L-glutamic acid solution and an enterococcus faecium suspension or glutamate decarboxylase free enzyme liquid at the ratio of 1 to 1 to 1 of the mass of the 732 cation exchange resin to the volume of the L-glutamic acid solution to the volume of the enterococcus faecium suspension or glutamate decarboxylase free enzyme liquid; and the yield of [gamma]-aminobutyric acid can be improved by 25.31-143.23% when it conducts a reaction in a water-bath oscillator at 80r/min and 37-43 DEG C or it conducts a stirring reaction at a low speed for 24-36h. According to the method provided by the invention, the 732 cation exchange resin can obviously improve the activity of the glutamate decarboxylase,and meanwhile, an exchange adsorption effect of the 732 cation exchange resin on [gamma]-aminobutyric acid is a process of purifying the [gamma]-aminobutyric acid, so that a downstream extraction andpurification process is simplified and production cost is reduced; and the method is simple and convenient and is green and environment-friendly.