15 results about "Microbial genetics" patented technology

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.

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.

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.

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.

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 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 discloses a kind of for screening of key regulatory factor of acid resistance of corynebacterium glutamicum resolving method and application, belong to the cross field of microbial genetic regulation, bioinformation calculation and industrial fermentation engineering.The resolving method for screening of key regulatory factor of acid resistance of corynebacterium glutamicum provided, including: the strain expression data of corynebacterium glutamicum under different fermentation acidity conditions are arranged;Initial candidate relationship framework model is constructed;Directional flow characteristic kernel function under the condition of multi-condition expression mode is constructed, and is combined with initial candidate relationship framework model, to infer the directionality influence intensity;The stability of the obtained directionality relationship is verified;Possible direction determination and link rationality check are carried out, and then the acid resistance regulation link and key gene are output.The present application can provide a kind of high reliability calculation means for the acid resistance improvement and precise positioning of key regulatory factor of industrial fermentation strain.

A truncated alginate lyase with wide temperature adaptability and its applications. This invention belongs to the fields of marine microbial genetic engineering and enzyme engineering, specifically disclosing a truncated alginate lyase, Aly7YΔCBM16ΔCBM32, and its applications. The amino acid sequence of this truncated form is shown in SEQ ID NO.4, and the nucleotide sequence is shown in SEQ ID NO.3. Compared with the wild type, this truncated form exhibits approximately 2-fold increased specific enzyme activity, more than 3-fold extended half-life at 40°C, and a significantly wider temperature and pH adaptability range. Furthermore, after normalization to 100% of the maximum activity of each enzyme, this truncated form retains approximately 78% activity in 1% SDS, demonstrates enhanced catalytic activity for Poly G, and achieves approximately 90% relative enzyme activity even under sodium-free conditions. This truncated form exhibits excellent environmental tolerance and can be used for the efficient preparation of low-polymerization alginate oligosaccharides primarily composed of ΔDP2–ΔDP4.

This invention belongs to the field of microbial genetic engineering and metabolic engineering technology, specifically relating to decarboxylase mutants in the indolepyruvate pathway, their mutant combinations, and their application in the production of indoleacetic acid. A decarboxylase mutant was obtained by mutating glycine at position 255 of the indolepyruvate decarboxylase kivD derived from *Lactococcus lactis* to tyrosine, and serine at position 386 to glutamic acid. kivD G255Y / S386E The applicant expressed kivD freely in the engineered recombinant Bacillus licheniformis strain BLI-2. G255Y / S386E The strain BlI-3 was obtained, and the indoleacetic acid (IAA) yield of BlI-3 reached 675.6 mg / L, which was 70.09% higher than that of BlI-2 and 258.44% higher than that of BlI-1, significantly improving the level of IAA synthesis by the host strain.

The present application belongs to the field of microbial genetic engineering technology, and particularly relates to tumor-targeting drug-producing engineering strains and a construction method and application thereof. The present application discloses a series of tumor-targeting drug-producing engineering strains, which can produce the anticancer drug romidepsin in situ in a tumor, can heterologously express romidepsin, and can produce romidepsin in situ in a tumor of a tumor-bearing small animal and has the activity of inhibiting tumor growth. That is, the present application provides a series of Escherichia coli Nissle 1917 recombinant strains, which are expected to become an anticancer live bacterial drug and will be applied to the clinic in the future, and therefore have good practical application value.

This invention provides a genome editing method for *Yersinia lipolytica* based on homologous recombination, belonging to the fields of microbial genetic engineering and synthetic biology. This invention constructs the tool plasmid pUrloxP3 to achieve efficient knockout and combined knockout of ylAS and ylPDH, completing site-specific integration and functional verification of exogenous genes RgTAL, 4CL, and CHS. The Cre / loxP system is used to recover the URA3 marker and eliminate the pYLXP'-Cre helper plasmid. This invention features high editing efficiency, standardized procedures, cyclical selection markers, and stable integration of exogenous genes, ultimately yielding a stable engineered strain without markers or helper plasmids. It is suitable for multi-round metabolic engineering and cell factory construction of *Yersinia lipolytica*.

This invention discloses a *Stachys pubescens* alcohol dehydrogenase, its encoding gene, and its applications, relating to the field of microbial genetic engineering technology. The alcohol dehydrogenase is any one of (1), (2), and (3): (1) the SvADH1 protein, whose amino acid sequence is shown in SEQ ID NO.3; (2) a protein obtained by substituting, deleting, and / or adding one or more amino acid residues to the amino acid sequence of the SvADH1 protein, resulting in a protein with more than 70% identity to the SvADH1 protein and associated with the redox of cross-linked solanol A; (3) a fusion protein obtained by attaching a protein tag to the N-terminus and / or C-terminus of (1) or (2). This invention has found that overexpression of the encoding gene of this alcohol dehydrogenase in *Stachys pubescens* significantly increases the yield of cross-linked solanol A, thus providing a new direction for the development of microbially derived cross-linked solanol A.

The application discloses a genetically engineered Gujeromyces reessii and a method for producing beta-glucan, and relates to the technical field of microbial genetic engineering. On the basis of wild-type Gujeromyces reessii, at least one of the following genes is overexpressed: beta-glucan synthase gene GSC1, FKS1 gene and RHO1 gene. The yield of beta-glucan produced by the genetically engineered Gujeromyces reessii obtained based on the above gene engineering modification can be increased by more than 30% compared with that of the wild-type strain. The harvested beta-glucan has good activity and can be directly used for high-end functional food, immune adjuvant, wound dressing and high-grade cosmetic raw materials; and the application provides a novel and efficient cell factory for green manufacturing of beta-glucan.