19 results about "Synthetase activity" patented technology

This invention relates to the fields of bioengineering and fermentation engineering, and discloses a genetically engineered *Streptomyces albopictus* strain that produces high levels of ε-polylysine and its fermentation production process. This genetically engineered strain uses *Streptomyces albopictus* strains acclimated to ε-polylysine tolerance as a chassis, and its genome integrates... ppc and dapf Through expression box, heterogeneous asd Expression cassettes, containing secretory signal peptides lysp Fusion expression cassettes and D404A / K499A point mutations pls Expression cassette. The fermentation process employs a two-stage pH control strategy, maintaining a neutral environment during the cell growth phase and adjusting to an acidic environment during product synthesis. This invention improves ε-polylysine yield through a synergistic strategy of enhancing precursor supply, constructing efflux detoxification channels, and increasing synthase activity; combined with an acidic fermentation process, it effectively inhibits product degradation, yielding a high-molecular-weight and highly uniform target product suitable for industrial production.

The present invention relates to novel glycoside synthetases for antibody drug complex (ADC) engineering. Enzyme variants, referred to as EndoSd-D232M and EndoSz-D234M, contain a polysaccharide binding and / or modification activity at the conserved N297 glycosylation site of the Fc region of an exemplary antibody. It has been proved that the glycoside synthase activity of EndoSd-D232M and EndoSz-D234M can be applied to various mAbs with different receptors as targets, including but not limited to Globo H, SSEA-4 and SSEA-3 series receptors (OBI-888, Globo H ganglioside), Herceptin (Her2 receptor), Perjeta (Her2 receptor) and Vectibix (EGFR receptor). It has been found that both the mAb-GlcNAc and the mAb-GlucNAc (F) are suitable receptors for both EndoSd-D232M and EndoSz-D234M. The invention also relates to a method for preparing the same.

The invention relates to the technical field of biological enzyme engineering, in particular to a mutant of nicotinamide adenine dinucleotide synthetase and application thereof. According to the nicotinamide adenine dinucleotide synthetase mutant, mutation of sites such as W11F, M12R, H37W, I40V, I40L, G43A, G43D, L46D, L46E, V55D, V55E, F60W, Y61S, L112I, L112K, L125E and L133T is carried out by taking NadR as a parent, so that the mutant can efficiently catalyze a low-cost substrate NR and ATP to generate NAD. Especially through mutation of the multiple mutation sites, the obtained mutant has better substrate binding capacity and catalytic efficiency and higher NAD conversion rate and enzyme activity (up to 12.49 U / mg), not only solves the technical problem of low activity of the existing NAD synthetase, but also remarkably reduces the production cost of NAD by using low-price NR instead of expensive NMN as a substrate, and has good application prospects. And a technical scheme with more economic benefits is provided for industrial production of NAD.

This invention discloses a culture medium for enhancing the activity of in vitro fiber-degrading bacteria in the gut microbiota, its preparation method, and its application, belonging to the field of microbial culture medium technology. The culture medium provided by this invention can effectively enhance the activity of fiber-degrading bacteria in the gut microbiota, promote their growth and metabolism, and thus significantly improve the fiber degradation capacity of in vitro microbiota. Compared with commonly used culture media, the concentration of total short-chain fatty acids in fiber fermentation products can be increased by up to approximately 50%. Compared with commonly used culture media, the culture medium provided by this invention can alter the composition of the fiber-degrading bacterial community in the gut microbiota, with significant differences detected in the abundance of nine genera, which may be the reason for the different fermentation efficiencies. The culture medium provided by this invention helps to more fully evaluate the fermentability of dietary fiber, and further study its metabolic pathways, product synthesis, enzyme activity, and biocatalytic mechanisms, which has significant value for the optimization of biomimetic digestive systems in the field of animal nutrition.

This invention discloses the application of lipoic acid analog formulations in the preparation of anti-cardiomyocyte senescence products. The lipoic acid analog DMAE-LA is N-(2-(dimethylamino)ethyl)-5-(1,2-dithiopentane-3-yl)pentanamide, with a concentration of 2-25 μM. DMAE-LA pretreatment effectively reduces intracellular ROS, improves mitochondrial function, inhibits the overexpression of p21 and HMGB1, and restores Lamin B1 levels, thereby alleviating the senescent manifestations of cardiomyocytes. DMAE-LA reduces H₂S oxidative depletion by inhibiting ROS generation and may promote H₂S synthase activity, increasing endogenous H₂S levels and further enhancing cellular antioxidant capacity. In summary, DMAE-LA can significantly inhibit cardiomyocyte senescence through multiple antioxidant mechanisms and organelle function protection, providing a potential intervention strategy for targeting cellular senescence in cardiovascular diseases.

The invention relates to a yeast gene modified cell containing GDP-fucose synthase polypeptide, which can be applied to synthesis of human milk oligosaccharide, and belongs to the technical field of gene engineering. According to the technical scheme, the yeast gene modified cell contains a heterologous nucleic acid sequence of a GDP-fucose synthase active polypeptide. The synthetase active polypeptide is obtained by modifying at least one site of the 20th site to the 29th site, the 40th site to the 53th site, the 75th site to the 81st site, the 95th site, the 148th site to the 158th site, the 193th site, the 215th site, the 219th site to the 21st site, the 227th site to the 232 site, the 239th site to the 241st site, the 259th site to the 264th site, the 301st site to the 302 site, the 306th site and the 310th site to the 316th site of an amino acid sequence shown in SEQ ID NO: 1. Compared with an original strain, the yeast gene modified cell has higher activity of synthesizing fucosyllactose, and a safe and feasible technical scheme is provided for industrial production of fucosyllactose.

The invention discloses a method for reducing the content of an M impurity in fusidic acid fermentation liquor. The generation of the M impurity is inhibited from a fermentation source by optimizing a fermentation culture medium and regulating and controlling pH in stages. A fermentation culture medium adopts a composite organic nitrogen source, contains soybean cake powder with specific grease content, and is matched with a yeast extract and corn steep liquor, so that a key precursor can be provided for fusidic acid synthesis, and the enzyme activity can be regulated; the pH is regulated in the early stage of fermentation to adapt to the proliferation requirement of the strain, M impurity synthesis is preliminarily inhibited, the pH is regulated in the middle and later stages to strengthen the activity of a target product synthetase, and M impurity synthetase expression is remarkably inhibited. The process is simple, subsequent complex purification is not needed, the yield of fusidic acid is increased, M impurities are reduced to 2% or below, and the method is suitable for industrial large-scale production.

A nutritional supplement includes one or more immune modulators that support a subject's cellular immunity, as well as ingredients that enhance the production and use of nitric oxide by the subject's body to better regulate the subject's cellular immunity. Such a nutritional supplement may include nano-fraction immune modulators, transfer factor, or plant transfer factor, as well as sufficient amounts of vitamin B9 and vitamin B12 to increase endothelial nitric oxide synthetase activity in a body of a subject. Methods for increasing endothelial nitric oxide synthetase activity in the body of a subject are also disclosed.

The present application relates to the technical field of biological enzyme engineering, and particularly relates to a nicotinamide adenine dinucleotide synthetase mutant and application thereof. The nicotinamide adenine dinucleotide synthetase mutant is obtained by mutating W11F, M12R, H37W, I40V, I40L, G43A, G43D, L46D, L46E, V55D, V55E, F60W, Y61S, L112I, L112K, L125E, L133T and other sites of NadR as a parent, so that the mutant can efficiently catalyze low-cost substrates NR and ATP to generate NAD. In particular, by using the above-mentioned multi-mutation point mutation, the mutant has better substrate binding capacity and catalytic efficiency, higher NAD conversion rate and enzyme activity (up to 12.49 U / mg), not only solves the technical problem of low activity of the existing NAD synthetase, but also significantly reduces the production cost of NAD by using the low-priced NR to replace the expensive NMN as the substrate, and provides a more economically beneficial technical scheme for the industrial production of NAD.

The invention provides a soybean GmACS18 gene and application of a biological material of the soybean GmACS18 gene to improvement of resistance of crops to soybean phytophthora root rot, and belongs to the technical field of genetic engineering. The biological material for overexpressing the gene comprises an expression cassette for overexpressing the GmACS18 gene, a recombinant vector for overexpressing the GmACS18 gene, a recombinant cell for overexpressing the GmACS18 gene, and a plant tissue for overexpressing the GmACS18 gene. It is found that the soybean GmACS18 gene can improve the defense ability of soybeans to phytophthora root rot by improving the ACC synthetase activity and the content of an ethylene synthesis precursor ACC in the ethylene synthesis process. The discovery provides important gene basis and theoretical support for researching related mechanisms of soybean phytophthora root rot resistance, and has important application value in soybean disease-resistant gene engineering breeding.

The invention belongs to the technical field of biological medicine, and particularly relates to a method for preparing pyrroloquinoline quinone and application. The invention provides a method for preparing pyrroloquinoline quinine, a seed culture medium is designed according to the requirements of microbial growth, microelements in the seed culture medium promote thallus growth, and a good thallus foundation is laid for subsequent synthesis of pyrroloquinoline quinine (PQQ); in a fermentation medium stage, namely a fermentation culture stage, PQQ synthesis enters a key stage, and trace elements beneficial to improving PQQ synthetase activity are pertinently supplemented, so that mass synthesis of PQQ is promoted. According to the method, the specific seed culture medium and the fermentation culture medium are utilized, trace elements are supplemented in the middle stage of fermentation, accurate regulation and control of the PQQ fermentation process are achieved, and the fermentation titer and purity of pyrroloquinoline quinone are improved.

The application discloses a genetic element for enhancing lactic acid metabolic flux of actinomycetes, and belongs to the field of synthetic biology and microbial metabolic engineering. sucC The application successfully constructs a single expression element and a co-expression element by cloning genes from Streptomyces coelicolor sucD , and verifies that the SucC protein and the SucD protein both have lactic acid coenzyme A synthetase activity through in-vitro protein purification and enzyme activity determination, and the enzyme activity of a protein complex (SucC-SucD, SucCD) expressed by the co-expression element is significantly higher than that of the single protein, indicating that the two proteins have a synergistic effect; the genetic element can efficiently catalyze the combination reaction of lactic acid and coenzyme A in vitro, accelerates the lactic acid metabolic speed, provides a core genetic element for the modification of the lactic acid metabolic pathway of actinomycetes, enriches a synthetic biology tool library, and has important industrial application prospects and academic value.

The present application provides a kind of derivative of dual-target inhibitor structure, the compound has the structure of formula (I) as shown in formula (I): formula (I) wherein, in formula (I) R1 It is selected from phenyl, 2-fluorophenyl, 3-fluorophenyl, 4-fluorophenyl, 4-chlorophenyl, 4-bromophenyl, 4-trifluoromethylphenyl, 4-methylphenyl, 4-ethylphenyl, 4-isopropylphenyl, 4-methoxyphenyl, 4-nitrophenyl, 4-methylsulfonylphenyl, thienyl, pyridyl, 3,5-difluorophenyl, 3,5-dichlorophenyl, 3,4,5-trifluorophenyl;R2 It is selected from H, halogen, trifluoromethyl, R2 It is in arbitrary position substitution position, single substitution or multiple substitution.The present application uses the derivative of the dual-target inhibitor structure for the use of the agent for preventing and treating plant pathogenic fungi.It can be seen that it has inhibitory effect on various plant fungi, and the inhibitory effect in sclerotinia is more significant.It has significant inhibitory effect on succinate dehydrogenase and chitin synthase activity.

The invention discloses a mutant of acylase and application thereof. The invention discloses a swine acylase mutant as well as a coding gene and a genetically engineered bacterium thereof. The acylase mutant disclosed by the invention has high enzyme activity stability in a wider pH environment, meanwhile, the activity of octanoyl alanine synthetase is improved, the synthesis efficiency of an octanoyl surfactant is high, and the acylase mutant has very high production and application values.

The invention provides a method for detecting the activity of phosphatidylserine synthetase and a method for screening a phosphatidylserine synthetase inhibitor, and relates to the technical field of biology. The method for detecting the activity of the phosphatidylserine synthetase is easy to operate, high in sensitivity, free of isotope labeling, low in cost, capable of rapidly evaluating the activity of the phosphatidylserine synthetase, capable of being used for screening phosphatidylserine synthetase inhibitors and high in flux. The screening method of the phosphatidylserine synthetase inhibitor, provided by the invention, is simple to operate and low in cost, and can realize high-throughput screening of the phosphatidylserine synthetase inhibitor.

The present disclosure relates to novel glycosynthase enzymes for antibody or antibody-drug conjugates (ADCs) engineering. The enzyme mutants, termed EndoSc-D233Q / E350N and EndoSc-D233Q / E350Q, contain the glycan conjugation and / or modification activity at the conserved N297 glycosylation site of Fc region of an exemplary antibody. It has been demonstrated that the glycosynthase activities of EndoSc-D233Q / E350N and EndoSc- D233Q / E350Q can be applied to various mAbs targeting different receptors. It has been found that both mAb-GlcNAc and mAb-GlucNAc(Fuc) were suitable substrates for both EndoSc mutants.

This invention discloses the Modhephene synthase gene of Artemisia annua spirochetane-type sesquiterpenoids. AaTPS25 Its mutants and applications; the Modhephene synthase gene was first identified and cloned from Artemisia annua. AaTPS25 The study clarified that the encoded protein can catalyze the synthesis of Modhephene from FPP, laying the foundation for the study of the biosynthesis and cyclization mechanism of this compound. Through site-directed mutagenesis, the AaTPS25 mutant with enhanced activity and the AaTPS26-A295E / Q and AabrSPS-A295E / Q mutants with Modhephene synthase activity were obtained, enriching the Modhephene synthase gene resources and providing key evidence for improving the biosynthetic yield of Modhephene and studying its catalytic mechanism.

The invention relates to a biological energy source and carbon emission reduction technology, and aims to provide a method for promoting methane sarcina to reduce CO2 by using H2 through improved coenzyme F420. Comprising the following steps: gradually domesticating methane sarcina in an air atmosphere which contains H2 and has gradually increased concentration gradient, so that the activity of coenzyme F420 in a finally obtained improved strain is improved to 3-5 times of that of an original strain, and the expression quantities of three key genes frhA, frhB and frhD of the coenzyme F420 are respectively improved by several times; the improved strain capable of stably inheriting is subjected to enlarged culture and is used for reducing CO2 by H2 to generate methane. The coenzyme F420 is directionally improved, the electron transfer rate is remarkably enhanced, the synergistic effect of a methyl coenzyme M reductase pathway and a hydrogenase system is directly promoted, the CO2 conversion efficiency and the methane production rate are improved, and the metabolic bottleneck of natural strains is broken through. By improving the strain, the activities of hydrogenase and ATP synthetase are enhanced, the cell growth division is accelerated, the apoptosis rate is reduced, and meanwhile, high metabolic activity is still maintained under low H2 partial pressure.

A nutritional supplement includes one or more immune modulators that support a subject's cellular immunity, as well as ingredients that enhance the production and use of nitric oxide by the subject's body to better regulate the subject's cellular immunity. Such a nutritional supplement may include nano-fraction immune modulators, transfer factor, or plant transfer factor, as well as sufficient amounts of vitamin B9 and vitamin B12 to increase endothelial nitric oxide synthetase activity in a body of a subject. Methods for increasing endothelial nitric oxide synthetase activity in the body of a subject are also disclosed.