66 results about "Microbial genetics" 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 discloses a 5 'UTR library, a recombinant expression vector and a genetically engineered bacterium for improving the yield of folamin in pathogenic bacterium Badei and application of the 5' UTR library and the genetically engineered bacterium, and belongs to the technical field of microbial genetic engineering. The method comprises the following steps: designing an SD region based on a 16S rRNA (ribosomal Ribonucleic Acid) 3'end complementary sequence of a Buddei pathogenic bacterium XBD101 serving as an original strain, regulating and controlling the number of bases between the SD sequence and an initiation codon AUG and optimizing an UTR secondary structure to construct a library containing 14 UTR sequences, and replacing three sequences N4A, N7A and N18A with the strongest translation ability in the library to the UTR region of a folamin synthesis key gene fclC, so as to obtain the folamin peptide. And finally, the capacity upgrading of the folamin chassis strain is realized, and an important support is provided for the industrial production of agricultural antibiotics.

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.

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 technical field of microbial genetic transformation, and particularly relates to a method for high-yield production of pleurotus ostreatus transformants, a genetic transformation system and application of the genetic transformation system. Through optimization of protoplast preparation conditions, the number of the obtained protoplast is 4.95 * 10 < 8 > CFU.mL <-1 >, and the regeneration rate of the protoplast in an OM-YEPS regeneration culture medium is 12.7%. A method for producing high-yield pleurotus ostreatus transformants is researched by using a PEG-mediated protoplast transformation method, a set of efficient and stable genetic transformation and screening method is established, about 200-300 positive transformants with stably expressed exogenous genes are obtained, and the transformation efficiency is 65.38%. The genetic transformation system of the high-yield Pleurotus ostreatus transformant, constructed by the invention, lays a solid technical foundation for subsequent gene function verification, metabolic engineering transformation and molecular breeding with excellent characters, and further accelerates the biological research and industrial application process of Pleurotus ostreatus and even other macro fungi.

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.

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 an arthrobotrys oligospora genetic engineering strain with nematode attracting activity, and belongs to the technical field of microbial genetic engineering, the genetic engineering strain takes arthrobotrys oligospora as a starting strain, and the genetic engineering strain is a strain obtained by knocking out an AoETF beta gene in an arthrobotrys oligospora genome. The arthrobotrys oligospora genetic engineering strain has nematode attraction activity, and can attract nematodes in soil to gather together so as to achieve the effect of efficiently capturing and killing the nematodes, thereby providing a basis for biological control of the nematodes. The invention further provides a construction method and application of the arthrobotrys oligospora genetic engineering strain with nematode attracting activity.

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 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.

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.

The invention provides a PEG / CaCl2 mediated Penicillium citrinum genetic transformation method, and belongs to the technical field of microbial genetic transformation, and the method comprises the following steps: adding a target gene segment into Penicillium citrinum protoplast suspension, and carrying out an ice bath reaction; the target gene segment is obtained by taking pJET-hph-02944 plasmid as a template and carrying out PCR (Polymerase Chain Reaction) amplification by adopting a hygromycin B resistance gene primer pair with gene sequences as shown in SEQ ID No. 1 and SEQ ID No. 2; adding a PTC (Positive Temperature Coefficient) buffer solution into the mixed system, uniformly mixing and standing; continuously adding a TB3 liquid culture medium containing ampicillin, and carrying out recovery culture; uniformly mixing the resuscitated protoplast with a molten TB3 solid culture medium, pouring a plate, and carrying out dark culture for the first time; then covering a TB3 solid culture medium containing hygromycin B and ampicillin, carrying out secondary dark culture to obtain a transformant, and transferring the transformant to a PDA plate containing hygromycin B for screening. According to the method, CaCl2-PEG is adopted for mediated transformation of Penicillium citrinum, the transformation efficiency is higher, and the transformation speed is higher.

The invention relates to a biofungicide based on the bacterium Pseudomonas lini strain S57, RGM 2930 CChRGM (Chilean Collection of Microbial Genetic Resources) for agricultural use, especially in saline-boric environments. The biofungicide can be developed as solid and liquid formulations. Where the strain S57, has fungicidal properties against the phytopathogenic fungi Botrytis cinerea. Fusarium oxysporum, Monilinia fructicola, Alternaria sp., Geotrichum candidum, and Macrophomina phaseolina, both in the presence and absence of saline-bone conditions.

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.

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 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.

The invention belongs to the cross technical field of microbial genetic engineering and food fermentation production, and particularly relates to a vanillin degradation related gene, application and an engineering strain for producing vanillin. The gene for regulating and controlling the production of vanillin by microorganisms is a 3-ketoacyl-ACP reductase gene, and the base sequence of the gene is shown in SEQ ID NO: 1. The 3-ketoacyl-ACP reductase gene is applied to regulation and control of degradation of vanillin. And the 3-ketoacyl-ACP reductase gene is knocked out from the chassis strain to obtain the 3-ketoacyl-ACP reductase. According to the invention, the fact that the fabG gene participates in the conversion of vanillin into vanillic acid is found for the first time, then the fabG gene is further utilized to modify the strain, the modification mode is highly targeted and has a remarkable effect, and through directional knockout of fabG and further knockout of vdh genes, phdB, fabG and modABC genes, the degradation pathway of vanillin is effectively blocked, and the product loss is reduced.

The invention discloses an engineering strain for increasing supply of cofactors and application of the engineering strain in improving production of epsilon-polylysine, and belongs to the technical field of microbial genetic engineering. The method comprises the following steps: by taking streptomyces albus for producing epsilon-polylysine as an original strain, simultaneously connecting a nicotinic acid ribose phosphate transferase gene pncB, a phosphoenolpyruvate carboxylase gene pck and a pyruvate dehydrogenase gene pdh in the strain with a pIB139 vector by utilizing a homologous recombination method to obtain a recombinant plasmid vector pIB139-pncB-pck-pdh, and introducing the recombinant plasmid vector into a competent cell to obtain the recombinant plasmid vector pIB139-pncB-pck-pdh. The engineering bacterium BP3 is obtained. The shake flask epsilon-PL yield of the engineering bacterium BP3 reaches 1.61 g / L and is improved by 30.89% compared with that of an original strain; the yield of fed batch fermentation reaches 37.21 g / L, the yield reaches 4.85 g / (L.d), and the maximum thallus concentration DCW reaches 43.47 g / L.

The invention belongs to the technical field of microbial genetic engineering and protein delivery, and particularly relates to an engineered bacterial secretion system for efficiently delivering protein and application of the engineered bacterial secretion system. Specifically, on the basis of analyzing a delivery mechanism of bacteroides fragilis GS086 type double-effect protein T6SS, engineering modification is performed on a toxic structural domain of the effect protein, and a bacterial secretion system capable of efficiently and simultaneously delivering a plurality of proteins is constructed. According to the system, a modified strain is a natural human intestinal symbiotic bacterium, the problems of high immunogenicity, poor stability and the like are effectively avoided, and protein can be delivered in situ in the intestinal tract to realize precise regulation and control of an intestinal flora structure and secretion of specific target protein, so that the system has a good practical application value.

The application discloses a method for optimizing protein translation extension process to improve protein yield of saccharomyces cerevisiae, and belongs to the technical field of microbial genetic engineering. The application improves the global protein synthesis capacity of saccharomyces cerevisiae by regulating the translation elongation factor in the translation initiation process, so that the protein content of saccharomyces cerevisiae is increased from 45.63 g / 100 g to 48.06 g / 100 g, and the protein yield is increased from 3.23 g / L to 3.46 g / L. The application provides technical support for low-cost and green single-cell protein production, and has a wide application prospect in the field of protein substitution.

This invention discloses a Bacillus bellis strain overexpressing a lipopeptide synthase gene, its construction method, and its application in fruit preservation. It belongs to the fields of microbial genetic engineering and postharvest fruit preservation technology. Using Bacillus bellis QB250122 as the starting strain, two rounds of genome editing were performed using a dual-plasmid temperature-sensitive CRISPR-Cas9n system. In the first round, the srfA promoter was replaced with the PHpaII superpromoter. In the second round, a complete expression cassette was inserted at the bacA site. The engineered strain produced 900-1200 mg / L of surfactantin. Applying a bacterial suspension to the surface of fruits such as mangoes can extend shelf life by 10-15 days.

The application provides a MhPHR2-MhSCL29 double-gene co-transformation synergistic regulation module and application, and belongs to the field of microbial genetic engineering.In the application, the phosphate-starvation response factor MhPHR2 is used as an upstream regulation hub, directly binds to a P1BS cis-acting element on a promoter of a downstream GRAS family transcription factor MhSCL29, positively activates the transcription of the MhSCL29, and forms a complete phosphate signal-mycorrhizal symbiosis regulation cascade.The nucleotide sequence of MhPHR2 in the synergistic regulation module is as shown in SEQ ID NO.1, and the nucleotide sequence of MhSCL29 is as shown in SEQ ID NO.2.The application improves the mycorrhizal symbiosis potential and the phosphorus utilization efficiency of a stock from the root.

This invention discloses an engineered strain of Streptococcus suis Δ07335-hSLY (classification name: Streptococcus suis Δ07335-hSLY, deposit date: May 13, 2026, deposit number: CCTCC NO: M2026937), its construction method, and applications, relating to the fields of microbial genetic engineering and drug screening technology. This invention uses Streptococcus suis SC19 strain as the starting strain and obtains the engineered strain SC19Δ07335 by knocking out the 07335 gene in its genome using homologous recombination technology. Compared with the starting strain SC19, the expression level of the hemolysin SLY gene in this engineered strain is significantly upregulated, increasing the success rate of the hemolysis test in the culture supernatant from 30% to 100%. Simultaneously, the expression of the capsular polysaccharide synthesis gene CPS is downregulated, the capsule becomes thinner, and the in vivo virulence is significantly reduced. The anti-hemolytic active compound screening system established based on this engineered strain is stable and reliable, and compounds with anti-SLY activity, such as baicalin, have been successfully screened. Animal experiments have verified that the survival rate of mice in the medium and high dose treatment groups of baicalin reached 100%.

The application discloses a recombinant attenuated Bordetella pertussis strain and a construction method and application thereof, and belongs to the technical field of microbial genetic engineering. The application provides a recombinant attenuated Bordetella pertussis strain, and the gene detoxified pertussis toxin expressed by the recombinant strain is 10 6 times lower in toxicity than the wild type, and the gene detoxified pertussis toxin derived from the CS strain of Bordetella pertussis is proved to have good protectivity in a mouse challenge experiment for the first time, and can be used for preparing products for treating or / and detecting or / and preventing the pertussis disease, and has a good application prospect.

The invention provides a DNA molecule for coding feruloyl esterase, a recombinant expression vector, a genetically engineered bacterium and application of the genetically engineered bacterium in production of feruloyl esterase, and belongs to the technical field of microbial genetic engineering. The nucleotide sequence of the DNA molecule for coding the feruloyl esterase is as shown in SEQ ID No. 1, and the amino acid sequence correspondingly coded by the DNA molecule is as shown in SEQ ID No. 2. The invention also discloses a recombinant expression vector and a genetically engineered bacterium which comprise the DNA molecule for coding the feruloyl esterase. According to the feruloyl esterase BccFae3074, a strain extracted from soil is used for sequencing, then a corresponding expression vector and engineering bacteria are obtained through genetic engineering modification, and the produced feruloyl esterase has relatively high enzymatic activity and yield; by optimizing the selection of carriers and the optimization of induction conditions, large-scale fermentation and industrial production are realized, ferulic acid is released through enzymolysis, high-value utilization of wastes such as straws is promoted, and pollution is reduced.

The invention provides a DNA molecule for coding feruloyl esterase, a recombinant expression vector, a genetically engineered bacterium and application of the genetically engineered bacterium in production of feruloyl esterase, and belongs to the technical field of microbial genetic engineering. The nucleotide sequence of the DNA molecule for coding the feruloyl esterase is as shown in SEQ ID No. 1, and the amino acid sequence correspondingly coded by the DNA molecule is as shown in SEQ ID No. 2. The invention also discloses a recombinant expression vector and a genetically engineered bacterium which comprise the DNA molecule for coding the feruloyl esterase. According to the feruloyl esterase BcFae4711, a strain extracted from soil is used for sequencing, then a corresponding expression vector and engineering bacteria are obtained through genetic engineering modification, and the produced feruloyl esterase has relatively high enzymatic activity and yield; by optimizing the selection of carriers and the optimization of induction conditions, large-scale fermentation and industrial production are realized, ferulic acid is released through enzymolysis, high-value utilization of wastes such as straws is promoted, and pollution is reduced.