902 results about "Microbacterium" patented technology

The invention belongs to the technical field of microorganisms, and particularly relates to recombinant escherichia coli containing a PDRN sequence and a preparation method thereof, and the preparation method comprises the following steps: S1, preparing a PDRN solution; s2, complementing the double strands of the PDRN into blunt ends; s3, constructing a recombinant plasmid; s4, carrying out mixed culture on a product obtained in the step S3 and escherichia coli DH5alpha; s5, screening the recombinants; s6, carrying out PCR (Polymerase Chain Reaction) amplification, and recording a strain from a fragment with the length of more than 200bp; s7, preparing a seed solution by adopting the strain prepared in the step S6; s8, strain fermentation; and S9, centrifugally collecting thalli. The method comprises the following steps: constructing a recombinant plasmid containing a PDRN fragment, introducing the recombinant plasmid into Escherichia coli, subsequently culturing the recombinant Escherichia coli to copy DNA in the Escherichia coli, extracting a purified exogenous gene fragment to obtain a strain containing a single fragment PDRN sequence, and getting rid of dependence on raw materials during subsequent extraction.

The present invention relates to a recombinant yeast with high squalene production, a construction method and a use thereof, wherein the recombinant yeast is a saccharomyces cerevisiae that expresses or overexpresses HMGR gene, ADA gene, LEU2 gene, MVA pathway gene and squalene synthase gene ERG9. The present invention integrates acetaldehyde dehydrogenase gene ADA and HMG-CoA reductase gene tHMGR in multiple copies in saccharomyces cerevisiae, integrates the screened high-activity phosphoketolase gene PK and phosphotransacetylase gene PTA, weakens epoxysqualene synthesis, strengthens the mevalonate pathway, overexpresses yeast endogenous squalene synthase gene, etc. to obtain a recombinant yeast with high squalene production, so that the production in the shake flask stage of the production process exceeds 5g / L, and the production in the fed batch fermentation stage exceeds 50g / L, breaking through the current bottleneck of microbial synthesis of squalene production, and is suitable for practical promotion and application.

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 provides a keto-alcohol acid reductoisomerase mutant and application of the keto-alcohol acid reductoisomerase mutant in construction of genetically engineered bacteria for high yield of D-pantothenic acid. In order to solve the technical problem that in the prior art, the yield of D-pantothenic acid synthesized through microbial fermentation is not high, semi-rational design of enzyme is adopted, and a keto-alcohol acid reductoisomerase mutant with substrate specificity is obtained and applied to construction of genetically engineered bacteria for high yield of D-pantothenic acid. According to the invention, a genetically engineered bacterium with high yield of D-pantothenic acid is constructed by utilizing the keto-alcohol acid reductoisomerase mutant through a CRISPR-Cas9 gene editing technology, so that the yield of D-pantothenic acid is increased by about 12.04%, and compared with an original strain, the valine accumulation amount in obtained fermentation liquor is almost unchanged compared with that of a control, and the yield of D-pantothenic acid is greatly improved. However, the accumulation of branched chain amino acid isoleucine is less, so that the modification of the substrate specificity of the keto-alcohol acid reductoisomerase is achieved.

The present invention provides: a sludge decomposing bacterium having a 16S rRNA gene comprising a base sequence having 97% or more identity with the base sequence recorded in sequence number 1, a bacterium having a 16S rRNA gene comprising a base sequence having a base variation number of 2 bases or less relative to the base sequence recorded in sequence number 1 and having target microorganism decomposing ability, and a microbial preparation for decomposing a target microorganism comprising the bacterium (a1), wherein the bacterium (a1) is a bacterium having a 16S rRNA gene comprising a base sequence having 90% or more identity with the base sequence recorded in sequence number 1.

The invention discloses a method for traceless gene editing of gram negative bacteria, a carrier and application of the carrier, and belongs to the technical field of microbial genetic engineering. The invention provides a vector for performing traceless gene editing on bordetella pertussis. The vector simultaneously comprises an antibiotic positive screening gene expression box and a sacB and galk negative screening gene expression box. According to the method, the sacB gene and the galk genome are synthesized into the double-reverse-screening system for the first time, and compared with a single-reverse-screening system, the reverse-screening efficiency is remarkably improved, and the dosage of a reverse-screening reagent is remarkably reduced. The invention provides a novel gene editing method for non-mode bacteria such as pertussis bordetella and the like, and has a good application prospect.

The invention discloses an RAA-CRISPR / Cas12a detection system of a circle virus avian origin type 1 and application of the RAA-CRISPR / Cas12a detection system, and relates to the technical field of microbiological detection. The detection system comprises an RAA amplification primer pair, crRNA, an FQ-ssDNA probe, an FB-ssDNA probe and an LbCas12a nuclease, and is characterized in that the detection system comprises an RAA amplification primer pair; the RAA amplification primer pair comprises an upstream primer of which the nucleotide sequence is shown as SEQ ID NO.5 and a downstream primer of which the nucleotide sequence is shown as SEQ ID NO.8; the nucleotide sequence of the crRNA is as shown in SEQ ID NO. 11. The RAA-CRISPR / Cas12a detection kit established by adopting the detection system developed by the invention has the advantages of high efficiency, high specificity and high sensitivity, can be used for on-site rapid detection of GyVg1, and provides a powerful diagnostic tool with a cost advantage for a basic-level working environment.

The invention relates to an application of a cytochrome P450 reductase 10273 inactivating agent in construction of an aspergillus terreus engineering strain for high yield of emodin or a derivative thereof. The invention further relates to aspergillus terreus engineering bacteria for high yield of emodin or the emodin derivatives and a construction method of the aspergillus terreus engineering bacteria. By knocking out the cytochrome P450 reductase gene 10273, the activation of anthraquinone methyl hydroxylase 4804 is blocked in aspergillus terreus, so that the hydroxylation pathway of the emodin is blocked, the purity of the emodin and the emodin-3-methyl ether in aspergillus terreus cells is improved, the production cost of the emodin and the emodin-3-methyl ether is reduced, and the method is suitable for industrial production. And a foundation is provided for the microbial industrial synthesis of the emodin and the emodin-3-methyl ether.

The invention relates to a recombinant bacterium for overexpressing uranyl binding protein and application of the recombinant bacterium, and belongs to the technical field of microorganisms. Bacterial outer membrane protein and uranyl binding protein are expressed in host bacteria, and the uranyl binding protein is anchored on an outer membrane of recombinant bacteria through the bacterial outer membrane protein, so that the uranyl binding protein anchored on the bacterial outer membrane can adsorb uranyl ions. Meanwhile, the invention finds that the expression quantity of the uranyl binding protein can be increased by performing fusion expression on the uranyl binding protein by using LPP-OMPA, so that the adsorption effect of uranyl ions is improved. The recombinant bacterium is prepared into a freeze-dried capsule product, and the freeze-dried capsule product can penetrate through a stomach barrier and is accurately delivered to intestinal tracts so as to realize uranyl ion adsorption.

The invention provides a keto-alcohol acid reductoisomerase mutant and application of the keto-alcohol acid reductoisomerase mutant in construction of genetically engineered bacteria for high yield of D-pantothenic acid. In order to solve the technical problem that in the prior art, the yield of D-pantothenic acid synthesized through microbial fermentation is not high, semi-rational design of enzyme is adopted, and a keto-alcohol acid reductoisomerase mutant with substrate specificity is obtained and applied to construction of genetically engineered bacteria for high yield of D-pantothenic acid. According to the invention, a genetically engineered bacterium with high yield of D-pantothenic acid is constructed by utilizing the keto-alcohol acid reductoisomerase mutant through a CRISPR-Cas9 gene editing technology, so that the yield of D-pantothenic acid is increased by about 12.04%, and compared with an original strain, the valine accumulation amount in obtained fermentation liquor is almost unchanged compared with that of a control, and the yield of D-pantothenic acid is greatly improved. However, the accumulation of branched chain amino acid isoleucine is less, so that the modification of the substrate specificity of the keto-alcohol acid reductoisomerase is achieved.

The invention discloses an ensifer sp.NJF-2 capable of performing biological defluorination on a polyfluoroalkyl compound, the ensifer sp.NJF-2 is preserved in China General Microbiological Culture Collection Center on September 12, 2024, and the preservation number is CGMCC NO.1. 19397. The invention also discloses an application of the strain in the aspect of biological defluorination, in-vivo and in-vitro transformation experiments show that the ensifer sp.NJF-2 can perform biological defluorination on the polyfluoroalkyl compound, and the ensifer sp.NJF-2 can perform biological defluorination on the polyfluoroalkyl compound. The strain can achieve the biological defluorination effect on various PFAS such as monofluorine, trifluorine, hexafluorine and the like.

The invention discloses lactobacillus mucus HG002 and application thereof, and belongs to the field of microbial medicine. The lactobacillus mucilaginosus HG002 is preserved in the China General Microbiological Culture Collection Center (CGMCC), the preservation number is CGMCC NO.36670, and the 16S rDNA gene sequence of the lactobacillus mucilaginosus HG002 is as shown in SEQ ID NO: 1. The strain is separated from excrement of healthy adults, the relieving effect of ALF is remarkably improved through the brand-new fermentation lactobacillus mucus HG002 strain and derivative EVs thereof in combination with a synergistic effect mechanism and optimized product design, many defects in the prior art are overcome, and wide application prospects and industrialization value are achieved.

The present invention provides a strain of Bifidobacterium adolescentis with the function of inhibiting α-glucosidase activity and secreting GLP-1 and its application, belonging to the field of functional microbial technology. The present invention isolates a strain of Bifidobacterium adolescentis B24728 from the feces of centenarians in Guangxi. The strain B24728 not only has the function of inhibiting α-glucosidase activity in vitro, but also has the function of high production of GLP-1, and animal experiments show that the strain B24728 has the efficacy of treating diabetes. At the same time, the strain B24728 is a human strain, has no species rejection reaction, and meets the safety requirements. Therefore, the strain B24728 and its culture can be used as food, health products or medicines for lowering blood sugar, and can be used to prepare medicines for the treatment of diabetes.

The invention discloses methanogen lyase homologous with a PeiR lyase sequence and application of the methanogen lyase, and aims to solve the problem that PeiR lyase protein of a methanogen cell wall peptide bond can participate in a biological process of hydrolyzing archaea cell walls, effectively kill methanogen and reduce methane production, and protein homologous with the PeiR lyase protein has potential methane reduction potential. According to the invention, a series of biological information software is utilized to identify protein sequences coded by methanogens virus from rumen microbiome sequencing data, and sequence homology between the proteins and PeiR protein is further analyzed to obtain a series of methanogens lyases. In order to realize the expression of the lyase, multiple segments of primers are designed to synthesize a target sequence, and the target sequence is successfully expressed in a prokaryotic expression system. Through the detection of crude enzyme liquid, the effectiveness of the lyase in the aspect of reducing the methane yield is verified in an in-vitro gas production test.

The invention relates to the technical field of microbiological detection and molecular biology, in particular to a specific detection primer for bifidobacterium longum subsp. Longum BBMN68 and application of the specific detection primer. The specific primer for detecting the bifidobacterium longum subsp.longum BBMN68, provided by the invention, comprises an upstream primer and a downstream primer, and nucleotide sequences are shown as SEQ ID NO.7-8. The invention also provides a kit for detecting the bifidobacterium longum subsp.longum BBMN68. The specific DNA fragment provided by the invention is a specific molecular marker of BBMN68, and the specific primer is designed aiming at the fragment sequence, so that the specific amplification of the strain can be realized, no cross reaction is caused to other related strains, the detection sensitivity is higher, and the detection requirements of samples with different concentrations can be met; the method can be used for specific detection and accurate quantification of the BBMN68 strain in yoghourt and other products, and has good practical application value.

The invention relates to a brand-new microbial natural metabolite, namely Fcl-8, which is derived from a fermentation solution of Xenorhabdius budapestensis XBD8, and is characterized in that the Fcl-8 is a new microbial natural metabolite, namely Fcl-8, which is derived from the fermentation solution of the Xenorhabdius budapestensis XBD8. The purified Fcl-8 is a snow white flocculent crystal and is very easy to dissolve in water, and the solid state of the purified Fcl-8 is as shown in Figure 1. The chemical structural formula of the Fcl-8 is as shown in a figure 2, the chemical formula is C57H102N14O12, the molecular weight is 1175.78744, and the typical secondary mass spectrum information of the Fcl-8 is as shown in a figure 3. The Fcl-8 is derived from a microbial natural metabolite, is novel in structure and high in biological activity, and has very high potential to be developed into a novel biopesticide.

The invention belongs to the field of membrane pollution control, and particularly relates to pseudomonas as well as a separation method and application thereof. The invention provides a pseudomonas, which is identified as Pseudomonas knackmussii HITSZ-Q1, is preserved in the Guangdong Microbiological Culture Collection Center, and has the preservation number of GDMCC (China General Microbiological Culture Collection Center) NO: 66162. The strain takes C6-HSL as the unique carbon source and nitrogen source, and the 16S rDNA sequence of the strain is as shown in SEQ ID NO. 1. The strain has a remarkable degradation capability on signal molecules such as C6-HSL, C8-HSL, 3-oxo-C12-HSL and the like, and the highest quenching rate can reach 98.9%. The strain and pseudomonas aeruginosa are co-cultured, so that the signal molecule concentration of the pseudomonas aeruginosa can be effectively reduced, and biofilm formation is inhibited. The strain is further prepared into a carrier in the form of immobilized pellets, the carrier is added into a membrane bioreactor, the operation cycle is prolonged from 6.5 days to 10.5 days, and the membrane pollution delay rate reaches up to 61.5%.

The invention provides a bifidobacterium longum subsp. Longum aFMT-103 strain, which is classified and named as Bifidobacterium longum subsp. Longum, is preserved in Guangdong Microbial Culture Collection Center, and has a preservation number of GDMCC No: 65181. The invention also provides a preparation method of the bifidobacterium longum subsp. Longum aFMT-103 strain. The invention further provides a microbial preparation containing the aFMT-103 bacterial strain. In addition, the invention also provides an application of the strain or the microbial preparation in preparation of an anti-depression product, and also provides an anti-depression product. The bifidobacterium longum subsp. Longum aFMT-103 strain has the advantages that the bifidobacterium longum subsp. Longum aFMT-103 strain is separated from the faeces of healthy adults; the strain has a remarkable anti-depression effect, can be used for preparing a preparation for resisting depression symptoms, and is of great significance in prevention and adjuvant therapy of depression.

The invention discloses methanogen lyase with the same protein family annotation as PeiR lyase and application of the methanogen lyase, and the methanogen lyase is obtained through homologous screening of Pfam protein family database annotation based on known PeiR lyase characteristics aiming at methanogen cell wall peptide bonds. The PeiR lyase protein can participate in the biological process of hydrolyzing archaea cell walls, methanogens are effectively killed, methane production is reduced, and the protein homologous with the protein has potential methane reduction potential. According to the invention, by integrating metagenome sequencing data of rumen microorganisms, screening methanogenic bacterium virus protein by using series bioinformatics software, and combining Pfam functional domain annotation to carry out homologous relationship analysis, a series of lyase is finally identified and is successfully expressed in a prokaryotic expression system, and meanwhile, an in-vitro gas production experiment result also shows that the methanogenic bacterium virus protein can be successfully expressed in a prokaryotic expression system. The crude enzyme liquid can significantly reduce the methane generation amount.

Aspects of the disclosure relate to methods and compositions for diagnosing and / or treating subjects having one or more symptoms of Autism Spectrum Disorder (ASD) or subjects at risk of developing ASD. In some embodiments, methods comprise determining and / or modulating levels of chorismate and / or a molecule within a chorismate metabolic pathway in a subject. In some embodiments, methods comprise determining and / or modulating levels of a microbial feature (e.g., a Sarcina bacterium) in a subject. In some embodiments, methods comprise determining and / or modulating levels of proton flux in a gastrointestinal tract in a subject.

The invention belongs to the technical field of biosynthesis, and particularly relates to a strain for producing sclareol as well as a construction method and application of the strain. In order to solve the problem of microbial synthesis of sclareol, phosphoketolase in an NOG pathway is mutated and optimized, phosphoketolase NaXpk from nanoarchaea archaeon is subjected to site-directed mutagenesis, a sclareol synthesis pathway is constructed in an escherichia coli host, the influence of NaXpk before and after mutation on the yield of sclareol is compared, and the yield of sclareol is improved. The S472F mutant and the S472Y mutant are determined, the S472F mutant and the S472Y mutant are applied to a sclareol production path, the sclareol yield of the finally obtained production strains can reach 623.3 mg / L and 655.2 mg / L, and the effect is remarkable.

The invention relates to the technical field of ginsenoside, aims to solve the problem of low conversion rate of ginsenoside Rg3 prepared by adopting a microbial conversion method in the prior art, and particularly discloses beta-glucosidase and a preparation method thereof, and application of the beta-glucosidase in production of ginsenoside Rg3. The preparation method of the beta-glucosidase comprises the following steps: S1, inserting a beta-glucosidase gene into a pET vector to obtain a recombinant plasmid; s2, inoculating the recombinant plasmids into competent cells, culturing the competent cells in an antibiotic-free culture medium and a resistant culture medium in sequence to form monoclonal antibodies, performing IPTG (isopropyl-beta-d-thiogalactoside) induction culture to form monoclonal strains, and storing the monoclonal strains in glycerol to obtain glycerol bacteria; s3, glycerol bacteria are placed in an LB culture medium to be cultured and then transferred into a fermentation culture medium, the fermentation culture medium is placed in a fermentation tank to be fermented, then centrifugal separation, thallus collection and re-suspension are conducted, beta-glucosidase is obtained and used for decomposing ginseng total saponins to produce ginsenoside Rg3, and the conversion rate of main products can reach 98%.

The invention discloses methylobacterium as well as a fermentation method and application thereof, and belongs to the technical field of microorganisms. The methylobacterium YLMb23.1 provided by the invention is subjected to taxonomic identification through 16S rRNA sequence analysis in combination with morphological characteristics, and the preservation number of the methylobacterium YLMb23.1 is CGMCC (China General Microbiological Culture Collection Center) No.32224. The methylobacterium YLMb23.1 has the capability of fixing nitrogen, producing ACC deaminase and IAA (indoleacetic acid), and has good drought tolerance and salt tolerance. A fermentation product of the methylobacterium YLMb23.1 is used for promoting the growth of wheat and corn, can be used as a microbial agent or bacterial fertilizer, and is applied to the agricultural market.

The invention relates to the technical field of biology, and particularly discloses a strain with a uric acid reducing characteristic and a growth-dependent uric acid characteristic, and the microbial preservation number of the strain is GDMCC No.65914. The uric acid reducing strain is screened from pickles by a transparent ring method, the 16S rRNA gene sequence of the uric acid reducing strain is studied, a resource library of the uric acid reducing strain is expanded, resources are provided for research and development of uric acid reducing drugs in the clinical field, non-target strains are effectively removed through a dual specific screening mechanism of uric acid dependent growth verification and liquid fermentation induced uric acid reduction, and the yield of the uric acid reducing strains is increased. The uric acid reduction and uric acid dependence function stability and metabolic specificity of the screened strain are ensured, the high uric acid reduction strain obtained through screening can be directly used for developing a novel microecological preparation or a uric acid reduction preparation, and compared with traditional chemical drugs, the high uric acid reduction strain has the advantages of being high in safety, good in biocompatibility and small in side effect; high-quality strain resources are provided for biological treatment of hyperuricemia and gout and development of uric acid detection reagents.

The invention relates to a clostridium perfringens phage and application thereof. The bacteriophage is a clostridium perfringens bacteriophage P2ACQJS03 (wherein the clostridium perfringens bacteriophage P2ACQJS03), and the preservation number of the clostridium perfringens bacteriophage P2ACQJS03 in the China Center for Type Culture Collection (CCTCC) is CCTCC NO: M 20242430. The bacteriophage provided by the invention is a virulent bacteriophage separated from the nature, tests prove that the bacteriophage has no toxic effect on normal microbial flora, and the DNA of the bacteriophage cannot encode virulence genes, so that the bacteriophage is high in stability; the bacteriophage disclosed by the invention is wide in host range, and large-scale industrial production can be realized. The bacteriophage provides an excellent strain resource for developing a novel antibacterial preparation, and has a good application and development prospect.

The invention discloses a six-joint fluorescence detection composition for detecting hand-foot-and-mouth disease pathogens, and belongs to the technical field of microbiological detection. The technical problem to be solved by the invention is how to quickly identify the typing of the pathogenic virus of the hand-foot-and-mouth disease. Therefore, the invention provides the composition for detecting or assisting in detecting the pathogenic viruses of the hand-foot-and-mouth disease. The composition comprises primer probes for respectively amplifying and recognizing enterovirus 71, enterovirus EV, coxsackie virus A group 16, coxsackie virus A group 6, coxsackie virus A group 10 and coxsackie virus A group 4. The composition provided by the invention is suitable for nucleic acid detection of enteroviruses extracted from samples such as throat swabs, anus swabs, intravesicular exudate, excrement, cerebrospinal fluid, virus isolate and the like, and has relatively high sensitivity and specificity.

The invention discloses recombinant escherichia coli capable of increasing the yield of fucosyllactose and a construction method and application of a fucosyltransferase mutant of the recombinant escherichia coli, and belongs to the field of synthetic biology and metabolic engineering. According to the invention, recombinant escherichia coli B20 and B21 are constructed based on key enzyme engineering transformation. Under the shake flask condition, the 3-FL production capacity of the recombinant strain is obviously improved to 6.20 g / L and 6.34 g / L from the initial 3.45 g / L, and the amplification reaches 79.7% and 83.8% respectively. The yields of 3-FL of the strain B20 and the strain B21 respectively reach 53.88 g / L and 54.64 g / L under the culture condition of a 3L fermentation tank. The recombinant escherichia coli for expressing the 2 '-FL is constructed, and the yield of the 2'-FL reaches 64.86 g / L in a 3L fermentation tank. The invention provides a new technical scheme for efficient microbial synthesis of the 3-FL.

The invention belongs to the field of biological medicines, and particularly relates to application of loganic acid in preparation of a medicine for treating arthritis. Specifically, through experimental research of a collagen-induced arthritis mouse model, the loganin acid is found to be capable of remarkably relieving arthritis symptoms, relieving joint swelling, synovitis and cartilage injury in a dose-dependent manner, and reducing the levels of proinflammatory factors TNF-alpha and IL-6 in plasma. By further combining 16S rRNA sequencing analysis, the loganic acid can remarkably regulate the intestinal microbiota structure of arthritis mice, increase the abundance of Lactobacillus murinus in the intestinal tract and promote the generation of tryptophan metabolite indole-3-acetic acid, so that the effect of resisting rheumatoid arthritis is achieved through an intestinal flora dependent mechanism. Therefore, the invention provides a new application of loganin acid in preparation of a medicine for treating arthritis, and the compound has further research and application values as a potential small molecule medicine.

The invention discloses a research method for researching an influence mechanism of high-fat diet on old-age health by using a mouse model, which comprises the following steps: S1, constructing a high-fat diet-induced mouse model: from normal diet feeding of mice to an old mouse stage, dividing the mice into two groups, and respectively performing high-fat diet feeding and normal diet feeding; s2, detecting physiological and functional indexes of the mice in the high-fat diet feeding group and the normal diet feeding group; s3, microbial diversity analysis: performing 16S rRNA sequencing to analyze the community structure of the intestinal microbiota of the mouse; s4, carrying out non-targeted metabonomics analysis: S4.1, carrying out intestinal tract non-targeted metabonomics sequencing; s4.2, carrying out non-targeted metabonomics sequencing on the liver tissues; s5, carrying out transcriptomics analysis; s6, performing conjoint analysis: performing the conjoint analysis on every two results of transcriptomics analysis, non-targeted metabonomics analysis and microbial diversity analysis; and S7, evaluating the influence of the high-fat diet on the health of the old rats by using the data obtained through analysis.

The invention discloses Escherichia coli with high fructose chondroitin yield and a production method of the Escherichia coli, and belongs to the technical field of microorganisms. On the basis of Escherichia coli K4, a coding gene of a key enzyme in a fructose chondroitin synthesis route is mutated, and a strain for improving the fructose chondroitin synthesis capability is constructed. The yield of fructose chondroitin in a 5 L fermentation tank reaches 10 g / L, the yield of fructose chondroitin in a 100 L fermentation tank reaches 15-20 g / L, the obtained final product is uniform in structure and stable in quality, the production cost is effectively reduced, the environmental pollution risk is reduced, and the strain is suitable for large-scale industrial production and application.