115 results about "Microbial Genes" patented technology

The invention belongs to the technical field of microbial genetic engineering, and particularly relates to an alpha-2, 3-sialyltransferase mutant and application thereof. The a-2, 3-sialyltransferase mutants V175N, P198A, G173D, D174Q, F196K and A315H are obtained by performing site-specific mutagenesis on six amino acids in an a-2, 3-sialyltransferase amino acid sequence coded by a gene derived from Campylobacter jejuni (OH4384), the yield of 3 '-sialyllactose is remarkably increased by single-point mutagenesis of the V175N, the yield of 3'-sialyllactose is remarkably increased by single-point mutagenesis of the V175N, the yield of 3 '-sialyllactose is remarkably increased by single-point mutagenesis of the P198A, the G173D, the D174Q, the F196K and the A315H, the optimal recombinant microbial strain 3 '-SL-09 (V175N / P198A / D174Q) is obtained through combination of multiple mutation sites, the yield can reach 5.91 g / L, the bottleneck problem of low catalytic efficiency of sialyltransferase is effectively solved, and an enzyme element with excellent performance is provided for high-efficiency and low-cost biological manufacturing of 3'-SL.

The invention belongs to the field of microbial genetic engineering, and provides schizochytrium limacinum with high DHA content and low DPA content and application of the schizochytrium limacinum. According to the strain, an n3 front-end desaturase gene derived from crypthecodinium cohnii is integrated to a 18S rDNA site of schizochytrium limacinum ALS01, and omega-6 type DPA is converted into DHA by utilizing an extension-desaturation way. Under the optimized conditions of a 5L fermentation tank (the inoculation amount is 5-20%, the temperature is 25-28 DEG C, the ventilation ratio is 1.0-2.0 vvm, and fermentation is performed for 72-168 hours), the biomass is larger than or equal to 150g / L, the total grease is larger than or equal to 60%, the DHA total grease proportion is larger than or equal to 53%, the DPA total grease proportion is smaller than or equal to 2%, and the DHA yield is larger than or equal to 47.82 g / L. The invention solves the problems of unstable fish oil resource and insufficient DHA purity in the traditional DHA production, provides a new strain for the industrial production of high-purity DHA, and has important application value.

The invention discloses a methane leakage microbial marker mining method based on multi-source data fusion and related equipment, according to the embodiment of the invention, a multi-dimensional feature space is constructed by fusing microbial gene data, spatial information and environmental geochemical data, and the data dimension and reliability of marker mining are improved; moreover, according to the embodiment of the invention, a mode of combining random forest and regression modeling is adopted, so that quantitative screening of the markers is realized, and manual intervention and subjective deviation are reduced; specifically, according to the embodiment of the invention, the markers are graded on the basis of comprehensive scores of three dimensions of importance, stability and universality, so that priority selection in subsequent practical application is facilitated; the embodiment of the invention is suitable for methane leakage identification of different sea areas and different geological backgrounds, has good generalizability and practicability, and can be widely applied to the technical field of marker analysis.

The invention belongs to the technical field of microbial genetic engineering, and particularly relates to an alpha-2, 6-sialyltransferase mutant and application thereof. The a-2, 6-sialyltransferase mutants M133L, E140D, D228H, N289D and G322Q are obtained by carrying out site-specific mutagenesis on five amino acids in an a-2, 6-sialyltransferase amino acid sequence coded by a gene derived from Photobacterium sp.JT-ISH-224, and compared with wild type alpha-2, 6-sialyltransferase, the yield of the single-point mutant 6 '-SL of the E140D and the yield of the single-point mutant 6'-SL of the G322Q are increased by 87.80% and 78.01% respectively. The yield of the optimal recombinant microbial strain 6 '-SL-7 (E140D / G322Q) obtained by mutation site combination can reach 1.471 g / L, the bottleneck problem of low catalytic efficiency of sialyltransferase is effectively solved, and an enzyme element with excellent performance is provided for high-efficiency and low-cost biological manufacturing of 6'-SL.

A microbial gene editing scheme automatic design method, system and storage medium; the method comprises: selecting a design object for different types of strains, the design object is bacteria or fungi; after determining the target gene, obtaining the target gene information from the NCBI database; the design scheme of bacteria comprises the following steps: determining the gRNA design region; selecting the optimal gRNA sequence; doing sequence complexity and GC content analysis; the design scheme of fungi uses a frameshift scheme: the gRNA of the frameshift scheme is set at any position not overlapping with other genes after the start codon in the gene; select gRNA sequence in gRNA design region, select the optimal gRNA sequence; design two pairs of four primer sequences for homologous arm identification primer; this scheme can replace the complicated and time-consuming manual scheme, save a lot of time, solve the problem of high cost in the design of the best site and the design of sgRNA sequence scheme of artificial gene knockout.

This invention relates to the fields of microbial genetic engineering and fermentation biomanufacturing technology, specifically disclosing a recombinant Corynebacterium glutamicum with high 5-aminolevulinic acid (ALA) production and its applications. Addressing the problems of existing strains such as crude enzyme activity regulation, inhibited cell growth, the need for external inhibitors, and low yield, this invention uses Corynebacterium glutamicum as a host and removes the gdhA gene without scarring to reduce precursor competitive metabolism. Site-directed mutations of the endogenous hemB gene (S288A, D128E, R231K) are performed to moderately reduce dehydratase activity. A high-expression plasmid pXMJ19-hemA containing the hemA gene from Rhodopsinus capsulatum is constructed and introduced into the modified strain to obtain a recombinant strain with optimized triple metabolism. This strain reduces product degradation without the need for external dehydratase inhibitors, does not affect cell growth, and achieves a yield up to 4.30 times higher than the control after 42 hours of fermentation, with ALA accumulation exceeding 8.9 g / L. The strain exhibits stable characteristics, the process is simple, and it has good industrial application value.

The invention belongs to the field of microbial genetic engineering. The invention particularly relates to a tylosin industrial high-yield strain as well as a construction method and application thereof. The sequence of the ALDH interfering gene is as shown in SEQ ID NO: 3. The industrial high-yield strain of tylosin is obtained by regulating and controlling the ALDH gene of an original strain. The strain is applied to fermentation production of tylosin and related derivatives thereof. The CRISPR i technology is utilized to inhibit in streptomyces fradiae to regulate and control ALDH gene expression, the gene is knocked out by using the homologous recombination technology, and then an engineering strain for high-yield tylosin is obtained. The engineering strain can improve the fermentation yield of tylosin by 6.8% and 9.9%.

The invention belongs to the technical field of microbial genetic engineering, and particularly relates to an acid-resistant lactobacillus plantarum engineering bacterium as well as a construction method and application thereof. The recombinant lactobacillus plantarum WCFS1-gadA-speA is obtained by constructing a recombinant expression vector pMG36e-gadA-speA and inducing the expression of two key genes, and the recombinant lactobacillus plantarum WCFS1-gadA-speA is obtained. The analysis of the fermentation capacity of the strain finds that compared with a single gene heterologous expression strain, the recombinant lactobacillus plantarum WCFS1-gadA-speA shows higher acid resistance and apple juice fermentation capacity. The recombinant lactobacillus plantarum WCFS1-gadA-speA with higher strong acid tolerance is obtained through a heterologous expression technology, a strain resource with better performance is provided for the food fermentation industry, and the quality and stability of a fermented product are improved.

The present invention discloses a recombinant saccharomyces cerevisiae for efficiently biosynthesizing inositol and its construction method and application, and belongs to the field of microbial genetic engineering. The recombinant saccharomyces cerevisiae of the present invention strengthens the expression of hexokinase gene hxk, inositol 3-phosphate synthase gene ino, inositol monophosphatase gene suhb, and realizes the rearrangement of glucose metabolism by knocking out the transcriptional repressor opi1 of inositol 3-phosphate synthase (Ino1) and glucose 6-phosphate dehydrogenase gene zwf1, and relieves feedback inhibition; In addition, the present invention further increases the yield of inositol by screening inositol external emission protein gene ompf, ompc and knocking out inositol internal transport protein gene itr1, itr2. The present invention realizes the efficient production of inositol (yield is as high as 195.7g / L), with good industrialization prospect.

This invention belongs to the field of microbial genetic engineering technology, specifically relating to an α-2,6-sialic acid transferase mutant and its application. This invention utilizes a mutant derived from *Lithocarpus lucida* (…). Photobacterium Five amino acids in the amino acid sequence of α-2,6-sialyl transferase encoded by the gene of sp. JT-ISH-224 were mutated at specific sites to obtain α-2,6-sialyl transferase mutants M133L, E140D, D228H, N289D, and G322Q. Among them, the E140D and G322Q single-site mutants of α-2,6-sialyl transferase showed increases in 6'-SL yield of 87.80% and 78.01%, respectively, compared with wild-type α-2,6-sialyl transferase. The optimal recombinant microbial strain 6'-SL-7 (E140D / G322Q) obtained by combining the mutation sites achieved a yield of 1.471 g / L, effectively solving the bottleneck problem of low catalytic efficiency of sialyl transferase and providing a high-performance enzyme element for the efficient and low-cost biomanufacturing of 6'-SL.

This invention discloses a method for preparing self-healing concrete based on microbial gene programming, belonging to the field of building materials technology. The method includes: constructing a recombinant engineered strain incorporating a urease gene cluster and a carbonic anhydrase gene; preparing a spore suspension and protecting it with a three-layer microencapsulation system of sodium alginate / chitosan / gelatin; preparing nutrient-releasing microspheres encapsulating calcium lactate and urea in a polylactic acid-glycolic acid copolymer; and mixing cement, standard sand, water, fly ash, microencapsulated spore particles, nutrient-releasing microspheres, nano-silica, and modified bentonite to prepare self-healing concrete. This invention enhances the urease activity of the strain through genetic engineering, protects the spores using a three-layer microencapsulation technology, and combines a nutrient-releasing system and nano-synergists to achieve efficient self-repair of concrete cracks.

This invention discloses a high-yield lactyl-3-4 ...5-4-4-4-4-4- N This invention relates to plasmid-free genetically engineered strains of tetrasaccharides and their applications, belonging to the field of microbial genetic engineering. The invention screened strains with higher activity. β -1,3-galactosyltransferase gene PmgalT Computer-aided enzyme function modification was used to achieve a shake-flask yield of 10.05 g / L for the constructed mutant. Subsequently, genome integration was performed... breast Multi-copy integration PmgalT * V27I / V39I / Y147F ‑galE‑galU A plasmid-free strain was constructed, enabling it to grow in shake flasks with lactoyl- N The yield of tetrasaccharides reached 14.4 g / L. Using glucose as the sole carbon source, the highest yield of 68.19 g / L was achieved at 64.5 h; using glycerol as the sole carbon source, the highest yield of 62.88 g / L was achieved at 60.5 h, providing a basis for its industrial production.

The invention relates to the field of microbial genetic engineering and synthetic biology, and particularly discloses a yersinia pseudotuberculosis temperature-sensitive promoter and application thereof. The screened and identified temperature-sensitive promoter element fills the blank of efficient constitutive promoter resources of yersinia pseudotuberculosis. The promoters can be used as universal gene expression regulation modules to be applied to metabolic engineering and synthetic biology research of yersinia pseudotuberculosis and other prokaryotic hosts, and are beneficial to high-efficiency expression of target protein or biosynthesis of high-value products. According to the method, the expression of the target gene can be regulated and controlled by changing the culture temperature without adding chemical inducers, so that the operation is convenient, the cost is saved, and the method has outstanding advantages in large-scale fermentation production.

The invention provides application of protein in construction of engineering bacteria for producing 6 '-sialic acid lactose, and relates to the technical field of microbial genetic engineering. According to the invention, new alpha2, 6-sialyltransferase with the potential of producing 6 '-sialyllactose is obtained through screening, and genes for coding precursor CMP-Neu5Ac synthetic pathway enzyme and alpha2, 6-sialyltransferase are introduced into escherichia coli to construct a new biosynthesis pathway of 6'-sialyllactose so as to construct engineering bacteria for efficiently producing 6 '-sialyllactose. Besides, a precursor CMP-Neu5Ac synthetic pathway enzyme and alpha2, 6-sialyltransferase are integrated and expressed in the engineering bacteria, so that the instability problem caused by plasmids is avoided, meanwhile, the dependence on antibiotics in the production process is reduced, and the environmental risk in the production process is reduced.

The application belongs to the technical field of kidney disease differential diagnosis, and particularly relates to a microbial gene marker for differentiating diabetic nephropathy and membranous nephropathy and application thereof. The application provides sufficient evidence for the differentiation and treatment of clinical diagnosis of diabetic nephropathy and pathological diagnosis of membranous nephropathy based on four microbial markers of Blautia, Akkermansia, Sphingomonas and Granulicatella.

The invention discloses a method for increasing the yield of lactoyl-N-neotetraose based on genome integration and transporter screening, and belongs to the field of microbial genetic engineering. According to the invention, a lactoyl-N-trisaccharide II synthesis module and a lactoyl-N-neotetraose synthesis module are rapidly integrated to different sites of an escherichia coli genome in a multi-copy manner by virtue of a CRISPR (clustered regularly interspaced short palindromic repeats)-associated transsposases gene editing technology, so that the use of plasmids is reduced, and the metabolic burden of cells is reduced. And in a 3L bioreactor, the yield of the lactyl-N-neotetraose reaches 30.56 g / L. Through over-expression of the transporter, the transporter which is most obvious in improving the yield of the lactoyl-N-neotetraose is screened to be YbSET, the yield of the lactoyl-N-neotetraose reaches 54.12 g / L, and excellent industrial application prospects are shown.

The invention belongs to the technical field of biological medicines, and particularly relates to an oral microbial gene marker for noninvasive diagnosis of esophageal cancer patients and application of the oral microbial gene marker. The invention provides an oral microbial gene marker for distinguishing esophageal cancer patients from healthy people, which consists of six microbial genes as shown in SEQ ID NO: 1-6, and the microbial genes are enriched in the oral cavity of a human body. The microbial gene distinguishing model disclosed by the invention has good distinguishing ability in esophageal cancer patients and healthy control people, and the feasibility, applicability and universality of the microbial gene distinguishing model in the esophageal cancer patients are proved.

The present application belongs to the field of microbial genetic engineering technology, and particularly relates to a recombinant bacterium for degrading crab shells, a construction method and application thereof. The present application carries out metabolic engineering modification on Pseudomonas putida KT2440 capable of utilizing crab shell substrate to grow and carry out life activities, utilizes overexpression of exogenous protease genes lasBT and IV to construct overexpression strains KT +IV , KT +lasBT The two modified engineering bacteria improve the protein utilization rate, enable the strains to better adapt to the crab shell substrate fermentation environment, enhance the growth ability of the strains, promote the high-value utilization of crab shells, and lay a foundation for realizing efficient and large-scale conversion of crab shells into high-value chemicals.

The invention relates to an underground water nitrogen metabolism function prediction and regulation method based on a three-dimensional fluorescence spectrum and automatic machine learning. The method comprises the following steps: collecting underground water microbial gene sequencing serial numbers in literatures and fluorescence emission spectrum data of corresponding water samples; according to the obtained gene sequencing data serial number, downloading microbial gene sequencing data, and carrying out normalization processing on required emission spectrum data; selecting a functional gene reflecting underground water nitrogen metabolism capability and calculating relative abundance; and constructing a machine learning model of underground water nitrogen metabolism. The selected optimal model can accurately predict and understand underground water nitrogen metabolism, reveal the influence of DOM fluorescence properties on an underground water ecosystem, and can be used for predicting the underground water microorganism nitrogen metabolism function of an unknown area.

This invention relates to the fields of microbial genetic engineering and brewing technology, and provides a PDC1 gene mutant strain resistant to 2-phenylethanol and its application in the brewing of wheat-aroma baijiu. The mutant strain is *Saccharomyces cerevisiae* PDC1_473 (HM 03), with the preservation number CCTCC M20252996. The PDC1 gene of this strain has a base mutation from T to C at position 473. When this mutant strain is applied to the solid-state fermentation of wheat-aroma baijiu, it becomes the absolutely dominant fungal community, significantly altering the microbial community structure of the fermentation system, inhibiting the growth of various conditionally pathogenic and spoilage bacteria, strengthening the fermentation environment centered on *Lactobacillus*, and significantly enhancing the rose, citrus, grassy, ​​fatty, and caramel aromas of the baijiu. It imparts a pleasant, rich ester aroma and complex aroma to the baijiu, increasing its fullness, and has broad application potential in the brewing of wheat-aroma baijiu.

Genetically engineered bacteria which express RNAs or proteins that produce ammonia upon decreases in phosphate concentrations are disclosed.

The invention discloses a mycobacterium typing detection primer group, a kit and application, the primer group is specifically designed based on 44 pathogenic microorganism genes in mycobacterium infection, can be used for accurate typing of mycobacteria, and is wide in coverage, high in sensitivity and strong in specificity; the method is of great significance to identification of infected strains and diagnosis and treatment of mycobacterium infectious diseases.

The invention belongs to the technical field of microbial genetic engineering, and discloses a construction method and application of a random mutant library of a transposon of methane-oxidizing bacteria, and a codon-optimized transposase (the optimized codon sequence is as shown in SEQ ID NO.1) is adopted, so that the random mutant library can be efficiently constructed in the methane-oxidizing bacteria Methylomicrobium alcaliphilum, and the construction of the random mutant library of the transposon of the methane-oxidizing bacteria is facilitated. Mutation transformants of 104 or more can be constructed through one-time transformation, and a large sample material is provided for breeding screening for improving the growth rate of methane-oxidizing bacteria.

The invention discloses an attenuated Bordetella pertussis recombinant strain as well as a construction method and application thereof, and belongs to the technical field of microbial genetic engineering. The invention provides an attenuated Bordetella pertussis recombinant strain, compared with a wild type, the toxicity of the gene detoxification Bordetella pertussis toxin expressed by the recombinant strain is reduced by 106 times, and the gene detoxification Bordetella pertussis toxin modified from the CS strain of Bordetella pertussis is proved to have good protectiveness for the first time in a mouse challenge experiment. The compound can be used for preparing products for treating or / and detecting or / and preventing pertussis diseases, and has a good application prospect.

This invention discloses a porcine CD40L trimer protein, a recombinant Bacillus subtilis strain expressing this protein, and its applications, belonging to the fields of microbial genetic engineering and livestock and poultry biological products technology. This invention utilizes Bacillus subtilis WB800N as a host and pHT43 as a vector to successfully construct a recombinant strain that efficiently secretes and expresses porcine CD40L trimer protein. Soluble expression of the porcine CD40L trimer protein was achieved. The amino acid sequence of the porcine CD40L trimer protein expressed by the recombinant strain is shown in SEQ ID NO:1. Immunological activity verification using this porcine CD40L trimer protein revealed that the CD40L trimer protein expressed in this invention can simultaneously activate humoral and cellular immunity, possessing practical application value as a novel vaccine adjuvant.

The invention discloses a Stemphylium transcription factor Sar1 gene and application thereof, and belongs to the technical field of microbial genetic engineering. The nucleotide sequence of the Stemphylium transcription factor Sar1 gene is as shown in SEQ ID NO.15, and the amino acid sequence of the protein coded by the gene is as shown in SEQ ID NO.4. The gene is a key transcription factor for synthesis of the Altersolanol A in Stemphylium, and the yield of the Altersolanol A can be remarkably increased through overexpression in Stemphylium cystosum. Therefore, the discovery and cloning of the Sar1 gene disclosed by the invention provide a basis for artificially modifying microorganisms and biologically synthesizing AltersolanolA.

The invention relates to the technical field of precision agriculture, in particular to a scientific fertilization method based on detection of soil conditions and microbial action, which comprises the following steps: collecting soil impedance and microbial indexes, correcting microbial distribution by using impedance depth, and executing environmental inhibition attenuation on nitrogen fixation and phosphorus solubilization rate by combining a carbon source and acid-base buffer capacity. And quantifying biological available nutrient supply, and generating a fertilizer discharge signal based on a crop demand gap and mechanical parameters. According to the method, the vertical cone index and the microbial gene abundance are collected, physical impedance data are introduced to correct the microbial spatial distribution weight, the metabolic activation model is constructed in combination with active organic carbon and the acid-base buffer capacity, and the actual nutrient conversion efficiency and the effective fertilizer supply total amount of nitrogen-fixing bacteria and phosphate solubilizing bacteria are quantified; biological fertilizer supply capacity is brought into a nutrient income and expenditure balance system, a discrete fertilizer discharge control instruction is generated according to actual gaps of crops and mechanical operation parameters, and the utilization rate of chemical fertilizer and agricultural ecological benefits are improved.

The invention belongs to the technical field of microbial genetic engineering, and relates to a recombinant engineering bacterium and a method for preparing cordycepin by using the recombinant engineering bacterium. The protein coded by the modified cordycepin synthesis related gene Cm1 contained in the recombinant engineering bacterium relates to mutation of Ser 696 Thr and Ile 760 Leu, and the amino acid sequence of the protein is shown as SEQ ID NO. 12. The cordycepin can be prepared with high expression quantity, simple separation and purification and low cost through fermentation of the recombinant engineering bacteria and separation and purification of fermentation products by utilizing the modified cordycepin to synthesize the related gene Cm1, the recombinant expression vector containing the gene Cm1 and the recombinant engineering bacteria containing the gene Cm1.

The present application belongs to the field of microbial genetic engineering technology, and specifically relates to a Kluyveromyces marxianus engineering strain for improving the secretion and expression level of recombinant glycoprotein and application thereof. The engineering strain is obtained by using gene editing technology to introduce a human UGGT1, UGGT2, SEP15 and EDEM2 expression frame into Kluyveromyces marxianus based on FIM1DU as a starting strain, and introducing a point mutation into an endogenous alpha-glucosidase II beta subunit Gtb1. UGGT1 and UGGT2 are used to introduce a reglycosylation module, and UGGT1 and / or UGGT2 are further enhanced when used in combination with SEP15; the introduction of EDEM2 helps to reduce the degradation rate of intracellular glycoprotein; and the point mutation of Gtb1 can slow down the deglycosylation process. The strain constructed by the above single modification or combined modification can improve the expression and secretion level of the recombinant glycoprotein without affecting the biomass accumulation of the strain, indicating that the engineering strain has important application value for the production of recombinant glycoprotein.

This invention relates to the field of microbial genetic engineering technology, specifically to a recombinant vector for enhanced oil recovery (EOR), engineered bacterial strains for EOR, their construction methods and applications, engineered bacterial strain agents and their applications, and methods for crude oil recovery. The recombinant vector for EOR of this invention includes a starting vector and an expression gene integrated into the starting vector; the expression gene includes a surfactant synthesis gene and a heat-resistant gene; the surfactant synthesis gene is the srfA gene; the heat-resistant gene is selected from the hsp70 gene, hsp60 gene, or dnaK gene. In this invention, a dual-gene synergistic modification strategy is employed, simultaneously introducing a heat-resistant gene and a surfactant synthesis gene and optimizing their expression, thereby achieving a dual enhancement of the engineered strain's environmental adaptability and metabolic function.