1674results about "Isomerases" patented technology

The invention provides a genetically engineered bacterium, a preparation method thereof and application of the genetically engineered bacterium in synthesis of sclareol. The genetically engineered bacterium comprises a CcLPPS gene derived from Cistanus crenatus, and a CcLPPS gene derived from Cistanus crenatus, the genetically engineered bacterium is selected from yarrowia lipolytica. According to the invention, the stably expressed sclareol efficient de novo synthesis strain is constructed, and no organic reagent or any path intermediate substance is added in the whole fermentation process, so that the production cost is greatly reduced, and the subsequent separation and purification steps are simplified. The engineering yarrowia lipolytica strain provided by the invention is high in production intensity and simple in fermentation process, has a relatively good application prospect, and lays a foundation for producing sclareol by a microbial fermentation method.

The invention relates to a saccharomyces cerevisiae strain for efficiently synthesizing cordycepin as well as a construction method and application of the saccharomyces cerevisiae strain, and belongs to the technical field of microbial genetic engineering. The construction method provided by the invention comprises the following steps: carrying out multi-copy genome integrated expression on heterologous codon optimized 2 '-carbonyl-3'-deoxyadenosine reductase genes and 3 '-adenosine monophosphate phosphohydrolase genes, so as to increase the dosage of key enzymes; and supplementing the defective gene of the engineering strain to obtain the saccharomyces cerevisiae strain B5U3 with high yield of cordycepin. According to the obtained saccharomyces cerevisiae strain for efficiently synthesizing the cordycepin, the cordycepin yield reaches 2.92 g / L after shake flask fermentation, the cordycepin yield reaches 7.5 g / L after fermentation in a fermentation tank, and a foundation is laid for safer and more reliable industrial production of the cordycepin.

The invention relates to the technical field of genetic engineering, and particularly discloses a genetic engineering bacterium for producing melanin as well as a construction method and application of the genetic engineering bacterium. According to the application, the yield of the melanin can be effectively increased by modifying a metabolic pathway of the genetically engineered bacterium, and the yield of the melanin reaches 6.2 g / L and 18.5 g / L respectively through shake-flask culture and 5L fermentation tank culture. Compared with the prior art, the yield of melanin produced by the genetically engineered bacterium is improved by 30% at the shake flask fermentation level, the fermentation yield of a fermentation tank is improved by 4.3 times, in addition, expensive tyrosine is changed into glucose as a fermentation precursor substance, the production cost is greatly reduced, and an efficient and feasible solution is provided for large-scale production of melanin.

The present disclosure concerns a fusion polypeptide for making acetyl-phosphate from glucose, a recombinant yeast host cell expressing the fusion polypeptide as well as methods of using the fusion polypeptide. The fusion polypeptide comprising (i) a glucose-6-phosphate isomerase moiety and (ii) a phosphoketolase moiety.

The invention belongs to the field of biological pharmacy and biological conversion, and particularly relates to a tagatose-4-epimerase mutant and application of the tagatose-4-epimerase mutant in preparation of D-tagatose. The tagatose-4-epimerase mutant disclosed by the invention is obtained by carrying out single mutation or combined mutation on an amino acid residue at a specific position of an amino acid sequence as shown in SEQ ID NO.1. Compared with wild type tagatose-4-epimerase, the mutant has the advantage that the catalytic activity is improved when the D-tagatose is prepared through conversion. The obtained tagatose-4-epimerase mutant has the advantages of being mild in reaction condition, green, environmentally friendly, single in product and easy to separate and purify, and the production cost is greatly reduced.

The invention belongs to the technical field of molecular biology, and particularly relates to sphingomonas paucimobilis recombinant engineering bacteria as well as a construction method and application thereof. The engineering strain is obtained by knocking out a metabolic bypass gene from sphingomonas paucimobilis, and the metabolic bypass gene is composed of a crtI gene or a phaC gene. The production amount of gellan gum can be increased by the delta phaC knockout strain and reaches 8.9 g / L. In addition, overexpression of energy metabolism related genes pgi or clpB or ycaJ is carried out, and the yield of a strain with the overexpressed pgi gene is increased to the maximum and reaches 9.5 g / L. Therefore, the pgi gene is overexpressed on the basis of the delta phaC knockout strain, the yield of gellan gum is further increased to 10.0 g / L, and the production efficiency is improved.

The invention relates to the technical field of microbial genetic engineering, in particular to a method for improving cordycepin synthesized by saccharomyces cerevisiae and saccharomyces cerevisiae engineering bacteria. According to the invention, codon-optimized 2 '-carbonyl-3'-deoxyadenosine reductase gene and 3 '-adenosine monophosphate phosphohydrolase gene from cordyceps militaris are expressed by using plasmids, and then the plasmids are transformed into host cells to obtain the saccharomyces cerevisiae engineering bacteria. And inoculating a seed solution obtained by seed culture of the activated saccharomyces cerevisiae engineering bacteria into a fermentation culture medium containing a metabolic effector, and carrying out fermentation culture to synthesize cordycepin. Metabolic effectors (Cu < 2 + >, Fe < 2 + >, Mg < 2 + >, Zn < 2 + >, citric acid, cysteine, aspartic acid, glycine, VB1 and tea polyphenol) are added into a fermentation culture medium strain, and the variety and concentration of the metabolic effectors are optimized, so that the yield and synthesis efficiency of cordycepin are remarkably improved. By using the combination of the strain obtained by the invention and the optimal effector, the yield of cordycepin in a fermentation tank reaches 2.9 g / L.

The invention discloses saccharomyces cerevisiae FNFHSc18 and application thereof, and belongs to the technical field of microorganisms. On one hand, the invention provides a saccharomyces cerevisiae engineering strain FNFHSc18 for synthesizing immune nutrients-beta-carotene and astaxanthin, and the preservation number of the saccharomyces cerevisiae engineering strain is CGMCC (China General Microbiological Culture Collection Center) No.24838; on the other hand, the invention provides application of the saccharomyces cerevisiae, the strain takes soybean meal as a solid state fermentation substrate, the content of crude protein and amino acid of the obtained product fermented soybean meal is remarkably increased, anti-nutritional factors such as oligosaccharide and urease are greatly reduced, more importantly, the fermented soybean meal is rich in beta-carotene and astaxanthin, and the content of the beta-carotene and the astaxanthin is greatly reduced. The soybean meal protein obtains new functional immune nutrition, so that the overall nutritional value of the soybean meal is improved, and the soybean meal reaches a leading level in the field of developing functional fermented soybean meal by utilizing saccharomyces cerevisiae.

The invention discloses a Yarrowia lipolytica strain for synthesizing delta-tocotrienol and application of the Yarrowia lipolytica strain, and belongs to the technical field of genetic engineering and bioengineering. According to the invention, a metabolic pathway of the delta-tocotrienol is constructed in the Yarrowia lipolytica, a mutant of a key enzyme, i.e., the uromelanic acid phytase, is screened, and the yield of the delta-tocotrienol is further increased by strengthening a shikimic acid pathway. The yield of delta-tocotrienol of the constructed engineering strain can reach 466.8 mg / L, a foundation is laid for subsequent biosynthesis of vitamin E compounds, and potential value and significance are achieved for development of synthetic biology.

The invention discloses a methanophilic genetically engineered bacterium for producing trehalose as well as a construction method and application of the methanophilic genetically engineered bacterium, and belongs to the technical field of industrial biology. The methanophilic genetically engineered bacterium capable of producing the trehalose is obtained by taking methanophilic bacteria methanophilic 5GB1, Alkalicicus glycogenes WONF2802 or methanophilic bacteria NG09 as host bacteria, introducing maltooligosyl trehalose synthase (MTS) into the host bacteria, and carrying out over-expression on maltooligosyl trehalose hydrolase (MTH), so as to obtain the methanophilic genetically engineered bacterium capable of producing the trehalose. Under the condition that methane or methanol serves as a carbon source, the yield of the produced trehalose can reach the gram level or above, a new low-carbon biosynthesis way can be provided for commercial production of the trehalose, and the methanophilic genetically engineered bacterium for producing the trehalose has a good industrial application prospect.

The invention relates to the field of biological engineering and technology, in particular to an enzyme for synthesizing glabridin, a biological synthesis method of glabridin and a bacterial strain. The invention discloses a series of glabridin synthesizing enzymes (phenylalanine ammonialyase, cinnamic acid-4-hydrogenase, tyrosine ammonialyase, p-coumaric acid coenzyme A ligase, chalcone synthase, chalcone reductase, chalcone isomerase, isoflavone synthase, 2-hydroxyisoflavone dehydratase, 4 '-oxymethyltransferase, 4'-hydroxymethyltransferase and 4 '-hydroxymethyltransferase) derived from glycyrrhiza glabra for the first time. ) can be used in the preparation of a compound (e.g., isoflavone 2 '-hydrogenase, isoflavone reductase, Vissisoketoreductase, isoprenyltransferase, pterocarpin reductase, oxidative cyclase, demethylase, cytochrome P450 reductase, and the like). The de novo synthesis of the glabridin in a microbial cell factory is realized for the first time, and the application prospect of the glabridin biological manufacturing industry is greatly promoted.

The present application relates to ketol reductoisomerase variants, polynucleotides encoding the variants of the present disclosure, L-valine-producing microorganisms comprising the ketol reductoisomerase variants of the present disclosure or the polynucleotides encoding the variants, and methods of producing L-valine using the microorganisms of the present disclosure.

The invention discloses L-arabinose isomerase, engineering bacteria and application, the amino acid sequence of the L-arabinose isomerase is shown as SEQ ID NO: 3, and the gene sequence for coding the L-arabinose isomerase is shown as SEQ ID NO: 2. On the basis of a genome of a Peribacillussp.S4 strain, a gene for coding the L-arabinose isomerase is excavated, and a stable prokaryotic expression system is constructed by performing codon optimization on the gene, so that the large-scale controllable production of the L-arabinose isomerase is realized, the yield of the enzyme is remarkably increased, the production cost of the enzyme is reduced, and the method is suitable for industrial production. A stable and economical enzyme source is provided for the production of D-tagatose; the L-arabinose isomerase expressed by the constructed engineering bacteria can significantly improve the yield of D-tagatose, and industrialization of D-tagatose is facilitated.

The invention particularly relates to a saccharomyces cerevisiae genetically engineered bacterium for de novo synthesis of 7-DHC as well as a construction method and application of the saccharomyces cerevisiae genetically engineered bacterium and belongs to the technical field of biology. According to the invention, a saccharomyces cerevisiae engineering bacterium SC9 is taken as an original strain, multiple times of multiple copies of tHMG1, DHCR24 and ERG1 are carried out on TY transposon, multiple copies of ERG2, POS5, ERG7, ERG11, IDI1 and ERG3 are carried out on TY transposon, and POS5, ERG3 and DHCR24 are singly copied on a genome, so that the content of intracellular reducing coenzyme II is increased, and a main path for synthesizing 7-DHC is enhanced. The genome single copy ACL, ACS1, ERG10, ERG19 and the like are used for enhancing the utilization of saccharomyces cerevisiae ethanol and dynamically regulating and controlling the synthesis of 7-DHC. The saccharomyces cerevisiae gene engineering strain constructed by the invention has high product accumulation, and lays a foundation for replacing a traditional multi-step chemical synthesis route and realizing industrial production.

The invention belongs to the field of biosynthesis, and in particular relates to LBD (Levandanenediol Pyrophosphate) synthase and engineered yeast for producing sclareol. In order to solve the problem that in the prior art, the sclareol biosynthesis yield is generally low, LSLPPs mutant containing at least one mutation of D730L, D374L, N674L or G379M is obtained by performing mutation and optimization on LSLPPs pyrophosphate synthase, and the mutant is used for sclareol synthesis. Meanwhile, in order to solve the problem of genetic instability caused by free plasmid expression of part of saccharomyces cerevisiae strains, a sclareol synthesis pathway is constructed in a yeast genome, and meanwhile, an acetyl coenzyme A synthesis pathway, an MVA pathway and a sclareol synthesis pathway are enhanced; chassis bacteria for synthesizing sclareol are modified in a manner of knocking out part of transcription inhibition factors, and the yield of a 5L fermentation tank reaches 26.11 g / L and is greatly improved compared with the prior art.

The invention belongs to the field of biosynthesis, and particularly relates to sclareol synthase and engineered yeast for producing sclareol. In order to solve the problem that in the prior art, sclareol biosynthesis yield is generally low, sclareol synthase is mutated and optimized, an SsScs mutant containing at least one mutation of Y491F, G307L or N269F is obtained, and the mutant is used for sclareol synthesis. Meanwhile, in order to solve the problem of genetic instability caused by free plasmid expression of part of saccharomyces cerevisiae strains, a sclareol synthesis pathway is constructed in a yeast genome, and meanwhile, an acetyl coenzyme A synthesis pathway, an MVA pathway and a sclareol synthesis pathway are enhanced; chassis bacteria for synthesizing sclareol are modified in a manner of knocking out part of transcription inhibition factors, and the yield of a 5L fermentation tank reaches 21.13 g / L and is greatly improved compared with the prior art.

The present disclosure provides compositions and methods for producing transgenic plants and other organisms that exhibit improved production of mogroside compounds, particularly mogroside V, as well as mogroside compounds, plants, and plant parts produced thereby.

The invention provides recombinant escherichia coli for producing chondroitin sulfate A and application of the recombinant escherichia coli, and relates to the technical field of genetic engineering. According to the recombinant escherichia coli disclosed by the invention, chondroitin synthase, chondroitin 4-O-sulfotransferase, N-acetyl glucosamine epimerase, UDP-glucose dehydrogenase and chondroitin sulfate degrading enzyme are overexpressed; wherein the amino acid sequence of the chondroitin sulfate degrading enzyme is as shown in SEQ ID NO. 5. The recombinant escherichia coli is inoculated into a culture medium for fermentation culture, the average molecular weight of the obtained chondroitin sulfate A is 800Da, and the yield is about 12.5 g / L. Therefore, low-molecular-weight chondroitin sulfate A can be obtained and the yield of chondroitin sulfate A can be increased by fermenting the recombinant escherichia coli disclosed by the invention.

The invention discloses a genetically engineered bacterium for producing glucuronic acid as well as a construction method and application of the genetically engineered bacterium, and belongs to the technical field of genetic engineering. According to the genetically engineered bacterium for producing glucuronic acid, an inositol oxidase gene MMIOX is integrated on a site of a uronic acid isomerase gene uxaC. According to the invention, an inositol oxidase gene MMIOX is integrated on a genome of a genetically engineered bacterium for producing glucuronic acid, and a uronic acid isomerase gene uxaC is knocked out at the same time, so that the genetically engineered bacterium can efficiently catalyze inositol reaction to generate glucuronic acid through the integrated inositol oxidase gene MMIOX; the glucuronic acid isomerase gene uxaC is knocked out, so that isomerization reaction of glucuronic acid can be avoided, and the yield of glucuronic acid is further increased.

The present invention discloses a yeast engineering bacterium containing a (-)-α-bisabolol synthase mutant and its application. By designing (-)-α-bisabolol synthase, the present invention obtains a mutant with high expression level, co-expresses the mutant with ERG20, highly expresses the key rate-limiting enzymes in the metabolic pathway, deletes the promoter to reduce the side reaction pathway, and adopts a multi-copy strategy to improve the metabolic flux in the (-)-α-bisabolol biosynthesis pathway. The shake-flask fermentation yield of the yeast engineering bacterium constructed by the present invention is close to 70 mg / L, which is about 35 times higher than that of the starting strain, and has broad application prospects in the biological fermentation production of (-)-α-bisabolol.

The invention discloses a pichia pastoris engineering bacterium for synthesizing bakuchiol from de novo by converting methanol as well as construction and application of the pichia pastoris engineering bacterium. A heterologous p-coumaric acid synthesis pathway is introduced to neutral sites of different chromosomes of pichia pastoris, a high-yield p-coumaric acid strain is obtained through gene knockout, overexpression or heterologous expression of tyrosine and phenylalanine synthesis pathway key genes of a shikimic acid pathway, a heterologous bakuchiol biosynthesis pathway is introduced on the basis, and a high-yield p-coumaric acid strain is obtained. After overexpression of bakuchiol synthetase, endogenous overexpression or heterologous expression of MVA pathway key genes and exogenous acetyl coenzyme A supply pathway genes, methanol concentration optimization and bacterial strain His4 gene supplementation, the yield of bakuchiol is effectively increased to 91.2 mg / L and is increased by 59.8 times compared with that of an initial bacterial strain, and the yield of bakuchiol in a 15L fermentation tank reaches 692.8 mg / L. The method has the characteristics of high conversion efficiency, low production cost, convenience in preparation, wide industrial application prospect and the like.

The invention discloses saccharomyces cerevisiae MBPSc21 and application thereof, and belongs to the technical field of microorganisms. On one hand, the invention provides a saccharomyces cerevisiae engineering strain MBPSc21 for expressing immune nutrient-beta-carotene, and the preservation number of the saccharomyces cerevisiae engineering strain MBPSc21 is CGMCC No.32663; on the other hand, the invention provides application of the saccharomyces cerevisiae, the strain takes soybean meal as a solid-state fermentation substrate, the crude protein content of the obtained product fermented soybean meal is remarkably increased, anti-nutritional factors such as oligosaccharide and urease are greatly reduced, more importantly, the fermented soybean meal is rich in beta-carotene, and the content of the beta-carotene is reduced. The soybean meal protein is endowed with new functional immune nutrition, so that the overall nutritional value of the soybean meal is improved, and a leading level is achieved in the field of developing functional fermented soybean meal by utilizing saccharomyces cerevisiae.

The invention provides a uracil production strain and a construction method and application thereof.According to the strain, on an E.coli UR14 genome by means of a CRIPSR / Cas9 gene editing technology, firstly, psuG genes, preTA genes, rutA genes and upp genes are knocked out, so that decomposition of uracil is blocked; then, a uridine phosphorylase gene udp and a pyrimidine-5 '-nucleotide nucleotidase gene ppnN are subjected to overexpression, and synthesis and accumulation of uracil are synergistically enhanced; and finally, overexpression of the ribose phosphate mutase gene pgm further enhances the conversion of a by-product ribose phosphate 1-precursor 5-ribose phosphate 1-pyrophosphate and improves the carbon utilization rate, and the obtained strain has good genetic stability and high fermentation yield, can stably produce uracil, and has wide application prospects.

The present invention relates to modified Dda helicases which can be used to control the movement of analytes such as polynucleotides. The modified Dda helicases are used in analyte detection and characterisation. The present invention also relates to novel protein pores and their uses in analyte detection and characterisation. The invention particularly relates to an isolated pore complex formed by a CsgG-like pore and a modified CsgF peptide, or a homologue or mutant thereof, thereby incorporating an additional channel constriction or reader head in the nanopore.

The embodiment of the invention provides a recombinant pichia pastoris strain as well as a construction method and application thereof. The construction method comprises the following steps: by taking a pichia pastoris strain as a host strain, constructing a dual-synthesis path of phenylalanine ammonialyase and tyrosine ammonialyase in the host strain to obtain a first engineering strain; removing chorismic acid feedback inhibition of the first engineering strain based on metabolic engineering to obtain a second engineering strain; optimizing an aromatic amino acid synthesis route of the second engineering strain to obtain a third engineering strain; knocking out a branch metabolic pathway of the third engineering strain to obtain a fourth engineering strain; increasing precursor supply of the fourth engineering strain to obtain a recombinant pichia pastoris strain; according to the construction method provided by the embodiment of the invention, the synthesis path of p-coumaric acid can be systematically optimized, the recombinant pichia pastoris strain for efficiently producing p-coumaric acid by taking methanol as a carbon source is constructed, and compared with a host strain, the recombinant pichia pastoris strain has the advantage that the yield of p-coumaric acid is remarkably increased.

The method for preparing D-mannose through catalysis can effectively reduce the amount of by-products glucose and fructose, and greatly improves the conversion rate of D-mannose. Specifically, engineering bacteria for expressing isoamylase genes and engineering bacteria for expressing alpha-glucan phosphorylase genes, glucophosphate mutase genes, difunctional enzyme glucophosphate isomerase / mannose 6-phosphate isomerase genes and mannose 6-phosphate phosphatase genes are utilized, starch or starch derivatives are used as substrates, and the starch or starch derivatives are used as substrates. A phosphate buffer solution and Mg < 2 + > are added, a preliminary catalysis system is constructed, after the reaction is completed, an incompletely-reacted substrate and maltodisaccharide exist in the reaction system, the incompletely-reacted substrate and maltodisaccharide can be hydrolyzed into glucose by glucoamylase, and the polyphosphoglucokinase can be used for catalyzing the reaction of the polyphosphoglucokinase under the assistance of sodium hexametaphosphate. All glucose is converted into phosphorylated glucose, then D-mannose is generated, and by-products in a system are removed while the yield is increased.

This invention discloses a D-allulose-3-epimerase mutant, its host cell, and its application in the synthesis of allulose, belonging to the field of genetic engineering technology. This invention utilizes a mutant derived from Ruminococcus CAG55 (… Ruminococcus sp. Simultaneous mutations at positions 47, 72, 114, and 221 of wild-type D-allulose-3-epimerase (CAG55) yielded a series of D-allulose-3-epimerase mutants, significantly improving their catalytic activity and stability. The mutants obtained by simultaneous mutations at positions 47, 72, 114, and 221 exhibited the highest catalytic activity. The D-allulose-3-epimerase mutants provided by this invention have significant application value in the production of D-allulose.

The invention discloses a recombinant halomonas for producing polyhydroxyalkanoate as well as a construction method and application of the recombinant halomonas. The recombinant halomonas comprises an exogenous gene, the exogenous gene comprises a combination of an aldD gene, a dhaT gene and an orfz gene, and the recombinant halomonas weakens the expression of an endogenous prpc gene. According to the invention, a P34HB synthesis route is successfully constructed through a synthesis route of exogenous introduction from 1, 4-butanediol (BDO) to 4-hydroxybutyryl coenzyme A, the proportion of each monomer in the copolymer can be effectively regulated and controlled, especially after exogenous addition of short-chain fatty acids (such as formic acid, acetic acid, propionic acid, butyric acid and the like), the synthesis of copolymers such as PHB, PHBV, P34HB, P34HB3HV and the like can be further improved, and the synthesis efficiency of the copolymer is improved. And the proportion of different monomers is adjusted, so that the diversity and yield of the copolymer are enhanced.

The invention belongs to the field of gene engineering, and discloses a sucrose isomerase mutant, a high-yield isomaltulose engineering bacterium and a construction method and application thereof. According to the sucrose isomerase mutant obtained through rational design of an enzyme molecular structure, the enzyme activity and the isomaltulose conversion rate of the sucrose isomerase mutant are remarkably improved, compared with a wild enzyme, the specific enzyme activity of the sucrose isomerase mutant is improved by 2.29 times, the isomaltulose conversion rate is improved to 98.9% from 91.1%, the impurity content is lower, and therefore the sucrose isomerase mutant is more suitable for synthesis of isomaltulose. A recombinant engineering bacterium of the high-yield isomaltulose engineering bacterium is further constructed; the recombinant engineering bacterium capable of efficiently expressing the sucrose isomerase is constructed by utilizing ubiquitin-like protein modified molecular genes to be fused with sucrose isomerase mutant coding genes, the enzyme activity of the prepared sucrose isomerase can reach 40.5 U / mg wet cells, and the recombinant engineering bacterium has a great application prospect in industrial production.

The invention belongs to the field of biological pharmacy and biotransformation, and particularly relates to a tagatose-4-epimerase mutant, a coding gene and application. The tagatose-4-epimerase mutant disclosed by the invention is obtained by carrying out single mutation or combined mutation on an amino acid residue at a specific position of an amino acid sequence as shown in SEQ ID NO.1. Compared with wild type tagatose-4-epimerase, the mutant has the advantage that the catalytic activity is improved when the D-tagatose is prepared through conversion. The obtained tagatose-4-epimerase mutant has the advantages of being mild in reaction condition, green, environmentally friendly, single in product and easy to separate and purify, and the production cost is greatly reduced.