13 results about "Xylulose" patented technology

The invention belongs to the technical field of biological enzyme engineering, and particularly relates to a D-psicose 3-epimerase mutant derived from rumen clostridium and application of the D-psicose 3-epimerase mutant. The mutant disclosed by the invention is obtained through specific single-point mutation on the basis of a wild type amino acid sequence of D-psicose 3-epimerase, and specifically, the mutant is obtained through mutation of the following five sites: L159V, Q164E, N238T, E288G and C289I; wherein mutants containing all five single point mutations are named as XT mutants. The mutants significantly improve the thermal stability of the enzyme and the catalytic conversion rate under high substrate concentration, especially under the high substrate concentration of 300-700 g / L, the conversion rate of D-psicose of the XT mutant is improved by 2-3% compared with that of a wild type, and the thermal stability of the XT mutant is improved by 28 times compared with that of the wild type. The mutant is suitable for a high-temperature and high-substrate-concentration industrial conversion system, the production cost of D-psicose can be remarkably reduced, and the mutant has important industrial application value.

The invention belongs to the technical field of synthetic biology, and particularly relates to recombinant escherichia coli for efficiently biosynthesizing lanosterol as well as a construction method and application of the recombinant escherichia coli. The method comprises the following steps: introducing exogenous squalene synthase (SQS), squalene epoxidase (SE) and oxidized squalene cyclase (OSC) genes into escherichia coli to construct a complete lanosterol synthesis route; the method comprises the following steps of: enhancing MEP pathway rate-limiting enzymes, namely 1-deoxy-D-xylulose-5-phosphate synthase (DXS), isopentenyl pyrophosphate isomerase (IDI) and farnesyl pyrophosphate synthase (FPS), so as to increase precursor supply, and further regulating and controlling the expression of key enzyme genes by adopting an arabinose promoter (PBAD). The lanosterol yield of the constructed engineering bacterium BW-2 reaches 8.02 mg / L and is increased by 40 times compared with that of an initial strain, and a brand new technical scheme is provided for green and efficient industrial production of lanosterol.

The application discloses high-yield gernien A engineering methanotrophs, a construction method and application thereof, and belongs to the technical field of metabolic engineering and synthetic biology. P mxaF expressing a gernien A synthase encoding gene gas overexpressing a 1-deoxy-xylose-5-phosphate synthase encoding gene in a gernien A synthesis pathway dxs1 and dxs2 a farnesyl pyrophosphate synthase encoding gene ispA a isopentenyl pyrophosphate isomerase encoding gene Bsidi simultaneously overexpressing 6-phosphogluconate dehydrogenase zwf1 and pfk1 and fba2 in an EMP pathway, to obtain gernien A engineering methanotrophs. The fermentation production of gernien A is carried out by using the engineering methanotrophs, and the yield of gernien A is obviously improved, so that the engineering methanotrophs have an industrial application prospect.

This invention discloses an engineered methanogenic bacterium that produces high levels of squalene, its construction method, and its applications, belonging to the fields of metabolic engineering and synthetic biology. This is achieved by using a strong promoter in the host bacterium (methanogenic bacterium). P mxaF Expression of squalene synthase encoding gene sqs Overexpression of the gene encoding 1-deoxy-xylulose-5-phosphate synthase in the squalene synthesis pathway dxs1 and dxs2 Farnesyl pyrophosphate synthase encoding gene ispA Isopentenyl pyrophosphate isomerase encoding gene My friends Simultaneously overexpressing glucose-6-phosphate dehydrogenase zwf1 and the EMP pathway pfk1 and fba2 An engineered methanogenic bacterium producing squalene was obtained. Using this engineered methanogenic bacterium for squalene fermentation production can significantly increase squalene yield and has excellent prospects for industrial application.

The application provides use of L-xylulose as a diagnostic marker for children with Kawasaki disease of immunoglobulin G non-responsiveness, and application of L-xylulose as a diagnostic marker in preparation of a Kawasaki disease diagnosis product, the diagnostic marker being a marker in a sample of children with Kawasaki disease, and the Kawasaki disease diagnosis product including a product for predicting and / or evaluating treatment effect of Kawasaki disease. The application first proposes a diagnostic marker of children with Kawasaki disease of immunoglobulin G non-responsiveness of L-xylulose, and uses the diagnostic marker for predicting and / or evaluating treatment effect of Kawasaki disease, and has good stability and repeatability.

The present disclosure relates to D-xylulose 4-epimerase, mutants thereof, and uses thereof. Specifically, the present disclosure relates to a polypeptide having D-xylulose 4-epimerase activity, a method for preparing said polypeptide, and use of said polypeptide in the preparation of L-pentose using D-xylose or D-xylulose as a raw material. Compared with the traditional preparation method in the prior art, the new method for preparing L-pentose discovered in the present disclosure has simpler production process and reduces the cost of producing L-pentose.

Provided herein are recombinant microorganisms having two or more copies of a nucleic acid sequence encoding a xylose isomerase, wherein the nucleic acid encoding the xylose isomerase is an exogenous nucleic acid. Optionally, the recombinant microorganism comprises at least one nucleic acid sequence encoding a xylulokinase and / or at least one nucleic acid sequence encoding a xylose transporter. The provided recombinant microorganism is capable of growing on xylose as a carbon source.

The invention belongs to the technical field of genetic engineering, and particularly relates to recombinant foal foal xylose as well as a construction method and application thereof. The recombinant foal foal capable of improving the bacterial cellulose yield and the xylose utilization amount is constructed by taking the foal foal foal as an original strain and overexpressing a xylose isomerase gene xylA, a xylulokinase gene xylB, a phosphopentose pathway key gene TKL and a structural gene BcsD. Under the fermentation conditions of pure xylose and xylose and glucose, the bacterial cellulose yields of the bacterial strain can reach 9.51 g / L and 8.1 g / L respectively and are increased by 553.23% and 44.75% respectively compared with original bacteria, and the highest xylose consumption of the bacterial strain under the fermentation conditions of pure xylose can reach 11.18 g / L. According to the method, the utilization rate of xylose is remarkably increased, the production efficiency of bacterial cellulose is improved, and a feasible solution is provided for replacing efficient conversion of traditional biomass resources with glucose as a carbon source.

The application discloses a synthesis method of xylulose-5-phosphate. The method takes a commercially available compound 1 as a starting material, and obtains the target product xylulose-5-phosphate through seven independent step-by-step reactions. The intermediates are compound 2 to compound 7 in turn. The synthesis method provided by the application is a step-by-step reaction, each reaction is an independent unit, the process parameters are accurately controllable and suitable for industrial operation errors, the side reactions are few, and the product selectivity is high. The method innovatively uses tetrabenzyl pyrophosphate as a phosphorylation reagent, replaces expensive reagents, and reduces the synthesis cost. The reaction condition of the method is mild, the operation is convenient, the crude compound 2 and the crude compound 4 can be directly used in the next step reaction, the post-treatment process is simple, and the route is simple and easy to be industrialized. The synthesis method of xylulose-5-phosphate has stable yield and accurate product structure, is suitable for large-scale industrialized preparation of xylulose-5-phosphate, and can effectively meet the market demand in the field of biological medicines.

The invention belongs to the technical field of microbial genetic engineering and industrial fermentation, and discloses an aspergillus niger engineering strain for producing L-malic acid by using xylose and a construction method and application of the aspergillus niger engineering strain. A three-gene recombination strain of an XR gene for coding xylose reductase, an XDH gene for coding xylitol dehydrogenase and an XK gene for coding xylulokinase through simultaneous overexpression is obtained through directional construction. Through synergistic overexpression of the XR gene, the XDH gene and the XK gene, the limitation that the starting strain LH-1 cannot utilize the xylose is successfully broken through, and effective utilization and directional conversion of the xylose are realized. The strain can be used for producing L-malic acid by using a low-cost xylose raw material, so that the production cost is remarkably reduced, a new technical path is provided for industrial production of organic acid, and the strain has a wide industrial application prospect.

The application provides use of L-xylulose as a diagnostic marker for children with Kawasaki disease of immunoglobulin G non-responsiveness, and application of L-xylulose as a diagnostic marker in preparation of a Kawasaki disease diagnosis product, the diagnostic marker being a marker in a sample of children with Kawasaki disease, and the Kawasaki disease diagnosis product including a product for predicting and / or evaluating treatment effect of Kawasaki disease. The application first proposes a diagnostic marker of children with Kawasaki disease of immunoglobulin G non-responsiveness of L-xylulose, and uses the diagnostic marker for predicting and / or evaluating treatment effect of Kawasaki disease, and has good stability and repeatability.

The invention discloses a beta-substituted phosphinamine mycin analogue as well as a preparation method and application thereof, and belongs to the field of plant protection. The molecular structure of the beta-substituted phosphinamine mycin analogue is formed by connecting two pharmacophores of phosphonic acid (ester) and hydroximic acid of phosphinamine mycin through a beta-substituent-containing propyl chain, the beta-substituted phosphinamine mycin analogue is obtained through beta-substituent structure optimization, and the structural general formula of the beta-substituted phosphinamine mycin analogue is as shown in formula (I). The compound acts on 1-deoxy-D-xylulose 5-phosphate reductoisomerase (DXR) in a 2-C-methyl-D-erythritol 4-phosphate path (MEP), is a herbicidal active compound with a new action mode, is high in herbicidal activity and safe to crops, and can be applied as a novel herbicide. Formula (I)

The invention belongs to the technical field of bioengineering, and relates to a recombinant engineering bacterium and application thereof in preparation of mannitol, and the recombinant engineering bacterium is a plasmid-free strain for producing a cofactor NAD < + > by using cheap xylose and nicotinamide. The following genes are knocked out from the strain: a gene ptsG for coding protein EIICBGlc in a glucose PTS system, mtlA for coding EIICA protein in D-mannitol transmembrane transport, a D-mannitol 1-phosphate dehydrogenase gene mtlD in a D-mannitol utilization path, purine de novo synthesis regulation protein purR, and srlAE in a sorbitol utilization gene cluster. The following genes are integrated in a genome of the strain: glucose transport assisting protein glf, glucokinase glcK, xylose utilization gene cluster xylose isomerase xlyA and xylulose phosphorylase xlyB, phosphoribose pyrophosphate synthetase prs, polyphosphate kinase ppk2, nicotinamide phosphoribose transferase nadV and nicotinamide mononucleotide adenylate transferase nadM. The strain is fermented by using glucose and xylose, and provides chassis bacteria for reaction needing cofactor circulation.