93 results about "Efflux" patented technology

The invention discloses a multi-target joint optimized antibiotic molecule design system and method applied to the field of biological medicine, and the method comprises the steps: obtaining FabI enzyme and AcrAB-TolC efflux pump structure data, extracting double-target space and physicochemical characteristics, and constructing a joint pharmacophore model containing a FabI inhibition domain and an efflux pump blocking domain; screening candidate molecules meeting a double-domain space matching threshold, screening high-affinity double-target molecules through conformation sampling and free energy calculation, and forming a lead compound library through multi-layer filtration of metabolic stability, membrane penetrability, quantum chemical properties and synthesis feasibility; carrying out electron effect, chain length or heteroatom fine tuning on dominant molecules through in-vitro bacteriostasis and efflux inhibition experiment feedback, and carrying out iterative optimization until MIClt is met; 2 [mu] g / mL and the efflux inhibition rate is gt; according to the present invention, the antibacterial effect and the drug resistance inhibition ability are significantly improved, the molecular synthesizability and the biological safety are ensured, and the engineering design new path is provided for the Gram-negative bacterium drug resistance crisis.

The present invention relates to a pharmaceutical composition for use against Gram-negative bacteria comprising at least one efflux pump inhibitor and at least one antibiotic. The invention also relates to the use of said pharmaceutical composition for resisting microorganisms, in particular bacteria, in particular gram-negative bacteria.

The invention provides a 2, 5-dimethylpyrazine production strain and a construction method and application thereof.According to the strain, key feedback inhibition is relieved through a perfect metabolic engineering strategy and strategies of knocking out a competitive pathway, introducing heterologous aminoacetone oxidase, deleting L-threonine efflux protein and the like, competitive enzyme conversion of aminoacetone is reduced through a system, and the 2, 5-dimethylpyrazine production strain is obtained. Spontaneous transformation of aminoacetone in Escherichia coli is enhanced, metabolism of L-threonine is expanded to synthesis of 2, 5-dimethylpyrazine, the yield of 2, 5-dimethylpyrazine is further increased, the constructed strain does not contain plasmids and has the advantages of clear genetic background, sustainable transformation and the like, and the 2, 5-dimethylpyrazine is produced through fermentation. The method is simple to operate, can be used for directly synthesizing 2, 5-dimethylpyrazine from the beginning by using a cheap carbon source, and has a very good application prospect.

The invention belongs to the technical field of natural pharmaceutical chemistry and medical application, and discloses a quinolone antibiotic synergist and application thereof in preparation of a medicine for treating bacterial infection. The structural formula of the quinolone antibiotic synergist is shown in the specification. The quinolone antibiotic synergist can effectively inhibit the activity of a staphylococcus aureus efflux pump, and the survival rate of mice infected with staphylococcus aureus can be remarkably increased when the quinolone antibiotic synergist is combined with quinolone antibiotics for use.

The present application relates to the technical field of bacteriostatic drugs, and particularly relates to application of traditional Chinese medicine monomers in preparation of bacterial efflux pump AcrB inhibitor or antibiotic activity improving drug and combined bacteriostatic composition. The traditional Chinese medicine monomers include red cedar flavone, stigmasterol, trichosanthin diol-3-benzoic acid ester, glycyrrhizic acid, alpha-bosanol, agastachin, acaciin, triptonylline C, rhein acid diglucoside, brassicasterol ferulate, cholesterin ferulate or calophyllolide G. The traditional Chinese medicine monomers can inhibit the efflux activity of AcrB, so that the drug molecules entering the bacteria continuously accumulate, thereby recovering the bactericidal efficiency of the existing antibacterial drugs and reducing the drug resistance of bacteria to the antibacterial drugs.

The invention discloses an intelligent synergistic administration composition and a preparation method thereof, and belongs to the technical field of pharmaceutical preparations and delivery. The composition takes lipidosome as a carrier, the surface of the lipidosome is modified with a peelable PEG protective layer with'enzyme / pH dual gating 'responsiveness, and the lipidosome is used for being activated under specific conditions of a tumor microenvironment to realize accurate targeting. The interior of the composition is covalently connected with a synergistic auxiliary drug for overcoming multi-drug resistance through chemical bonds sensitive to acid, and a main-effect anti-cancer drug is physically entrapped. After entering the target cell, the auxiliary drug is preferentially and rapidly released in the lysosome by means of the acid-sensitive bond so as to inhibit the drug efflux pump function; and then the main-effect medicine is slowly released, so that programmed sequential administration is realized. Through the collaborative design of intelligent shelling and sequential release, the technical problems of poor targeting property and difficulty in overcoming drug resistance in drug delivery are solved, and the collaborative anti-tumor effect is remarkable.

The application belongs to the technical field of pharmaceutical chemistry, and particularly relates to a pyrimidine and thienopyrimidine derivative, a preparation method and application thereof. The pyrimidine derivative in the application is a compound with the structure of formula I, and the thienopyrimidine derivative is a compound with the structure of formula II. The pyrimidine and thienopyrimidine derivative can be used as an AcrB efflux pump inhibitor, and can significantly enhance the antibacterial activity when combined with an antibacterial drug. The Nile red experiment shows that the compound 64c can completely inhibit the AcrB-mediated efflux at a concentration of 50 μM, and the effect is better than that of the positive control PA beta N. The compound in the application has novel structure and excellent activity, and can be used for preparing an AcrB efflux pump inhibitor for reversing bacterial drug resistance and an antibacterial sensitizing drug.

The invention discloses a recombinant genetically engineered bacterium for producing beta-alanine by dynamically regulating and controlling a competitive pathway and application of the recombinant genetically engineered bacterium, heterologous key genes pycCG and NCgl0580 are over-expressed on plasmids, accumulation of a beta-alanine precursor oxaloacetic acid pool is increased, and efflux of beta-alanine is enhanced; a heterologous gene gapN is introduced to adjust a glycolytic pathway, so that the efficiency of the glycolytic pathway is enhanced, and the carbon flow in a beta-alanine synthesis pathway is increased; the expression activity of the gene gltBD is up-regulated so as to enhance the supply of an amino donor when oxaloacetic acid is converted into aspartic acid; an EsaI / EsaR group sensing system is introduced to dynamically regulate and control an aspartic acid competition branch; after the thrA gene promoter is replaced by PesaS, the situation that excessive metabolic flow enters an aspartic acid competition branch is effectively weakened, the carbon flow is pulled to the synthesis direction of beta-alanine to the maximum extent, and the yield of beta-alanine is obviously increased.

This invention provides an engineered bacterium for producing ectoine, its preparation method, and its application. The engineered bacterium is prepared using a method comprising the following steps: using *Corynebacterium glutamicum* as the starting strain, feedback inhibition by aspartate kinase LysC is relieved, the activity of the gene lysE encoding lysine efflux permease is reduced, and the ectoine synthesis gene cluster ectABC is expressed. Based on this, the activity of any one or at least two of the following—diaminobutyrate acetyltransferase EctA, pyruvate carboxylase Pyc, or aspartate kinase LysC—is enhanced, and / or the activity of any one or at least two of the following—maloquinone oxidoreductase Mqo or homoserine dehydrogenase Hom—is reduced to further increase ectoine yield.

The invention discloses an ingenol ABC transport protein ElABCG39 as well as a coding gene and application thereof. The protein is positioned in a cytoplasmic membrane, and expression of the protein in yeast proves that the protein has ingenol transmembrane efflux transport function, improves the ingenol tolerance of the yeast, and proves that the ElABCG39 has certain substrate specificity in the yeast. The ingenol ABC transporter ElABCG39 can be used for producing ingenol by fermentation of microorganisms or plant tissues.

The invention discloses a parameterized constraint system and method for efflux pump avoidance and off-target risk inhibition, which are applied to the field of biological medicines, and aims to solve the dual problem that toxic risks are caused by efflux pump mediated drug resistance enhancement and off-target combination of existing antibacterial drugs. The method comprises the following steps: constructing an efflux pump identification avoidance five-dimensional feature space and a target spot specificity geometric-electrical constraint boundary, performing structure mapping and deviation degree evaluation on candidate molecules, and triggering directional modification; the target matching is verified through molecular docking, and if the target does not reach the standard, the pharmacophore is locally adjusted; virtual screening is carried out based on an off-target protein database, a secondary structure disturbance mechanism is started for high-risk molecules, and a stereoisomerism or electrical reversal group is introduced to destroy non-target binding; according to the method, collaborative optimization of antibacterial efficacy, drug resistance avoidance and safety risk is achieved, and the research and development efficiency and druggability of candidate molecules are remarkably improved.

The application discloses application of tegaserod maleate in preparation of an antibacterial drug synergist, and proves that the tegaserod maleate can produce a synergistic antibacterial effect with a plurality of commonly used antibacterial drugs (including tylosin, tetracycline, enrofloxacin, ampicillin and the like), can significantly enhance the antibacterial activity of the antibacterial drugs on gram-negative bacteria, and reduce the drug resistance of bacteria to the antibacterial drugs; the antibacterial composition composed of the tegaserod maleate and the antibacterial drugs can be used for preparing a drug for treating escherichia coli infection, and the synergistic antibacterial mechanism is mainly to destroy the inner and outer membrane permeability of bacteria, regulate the proton motive force of bacteria, inhibit the activity of bacterial efflux pumps, interfere with the energy metabolism homeostasis of bacteria and induce the bacteria to produce oxidative stress. The application provides a new technical strategy for the treatment of clinical escherichia coli infection, and has important clinical application value and industrialization potential.

The invention provides an engineering bacterium for producing spermidine and a preparation method of the engineering bacterium, and relates to the field of genetic engineering. According to the invention, arginine decarboxylase, aspartate kinase, aspartate-semialdehyde dehydrogenase, spermidine efflux protein (MdtI / MdtJ), carboxylaminopropyl agmatine dehydrogenase (CAPADH), carboxylaminopropyl agmatine decarboxylase (CAPADC) and aminopropyl agmatine urea hydrolase (APAUH) are subjected to overexpression in escherichia coli by using a gene engineering technology, and then the escherichia coli is subjected to enzyme deactivation, so that the escherichia coli is obtained. The genetically engineered bacterium capable of producing the spermidine can be obtained by simultaneously knocking out a spermidine transport system (PotBCAD), a spermidine-N-acetyltransferase (spermidine-N-acetyltransferase) and a homoserine dehydrogenase (homoserine dehydrogenase), so that the genetically engineered bacterium capable of producing the spermidine can be obtained. The engineering bacterium greatly reduces the production cost of spermidine, has a wide application prospect, and lays a foundation for green production of spermidine.

The invention discloses a tilmicosin nanostructure lipid carrier and a preparation method thereof. The preparation method comprises the following steps: swelling poloxamer 188 in distilled water to serve as a water phase; the preparation method comprises the following steps: mixing and melting stearic acid and oleic acid, sequentially adding tilmicosin and Tween 80, and stirring to form an oil phase; controlling the water phase and the oil phase at the same temperature, adding the oil phase into the water phase, shearing at a high speed, and homogenizing at a high pressure to obtain a pre-emulsion; and mixing the pre-emulsion with water and then carrying out secondary high-speed shearing. The carrier can keep good stability under the acidic condition, can significantly improve the oral bioavailability of tilmicosin in piglet bodies, can promote cell uptake, and can reduce the efflux effect of a drug transporter, thereby effectively improving the efficiency of tilmicosin entering intestinal epithelial cells. In addition, the carrier can well cover the unpleasant odor and bitter taste of the medicine, the palatability of tilmicosin is improved, and the influence of tilmicosin on pig ingestion is avoided.

The invention provides a genetically engineered bacterium for co-production of L-threonine and L-valine and a fermentation method of the genetically engineered bacterium, and belongs to the technical field of bioengineering and fermentation, the genetically engineered bacterium co-expresses key genes alsS, leuDH, ilvC and ilvD of an L-valine synthesis pathway and efflux related genes ygaZ and ygaH on plasmids, the expression of the L-valine synthesis pathway is regulated by combining with a promoter, and the L-threonine and L-valine co-production is realized. The genetically engineered bacteria for co-production of the L-threonine and the L-valine are obtained; the invention also discloses a fermentation method of the genetically engineered bacterium. According to the technical scheme provided by the invention, efficient co-production of L-threonine and L-valine is realized, the synthesis efficiency of thalli is improved, and the fermentation production cost is reduced.

The invention belongs to the technical field of microorganisms, and provides a gene combination for degrading organic arsenic, an engineering bacterium and application of the gene combination. The gene combination comprises a nitroreductase gene BsntrA, an arsenate reductase gene ArsC2 and an efflux pump gene BsexpA which are from brevundimonas M20, the gene combination is used for constructing a recombinant expression vector and transforming the recombinant expression vector into a host cell, the obtained gene engineering cell forms an organic arsenic reduction-secretion system through protein expressed by the gene, nitro reduction, arsenic (V) reduction and HAPA (III) secretion of roxarsone are achieved, the degradation rate of the gene engineering cell to roxarsone in wastewater reaches 75.6%, and the gene engineering cell has a good application prospect. The drug resistance to roxarsone is obviously improved, and the compound can be efficiently used for removing organic arsenic in pollutants.

The invention belongs to the technical field of biosynthesis, and particularly relates to a method for regulating and controlling stevioside production through cofactors and product transport. According to the invention, an efficient stevioside biosynthesis system is constructed: in the aspect of chassis cell optimization, transcription factors for regulating and controlling an MEP pathway and key genes of the MEP pathway are overexpressed, and supply of terpene precursors is enhanced; the introduction of a heterologous MVA pathway achieves sufficient supply of terpenoid precursors. Meanwhile, on the cofactor regulation level, an NADPH regeneration network is constructed, so that the coenzyme level is improved, and the ATP synthesis module and the carbon metabolism flux are synchronously enhanced; in order to solve the problem of product transport, an efflux transport system is constructed, efflux of stevioside is improved, and pressure on cells is reduced, so that the production capacity of stevioside is remarkably improved.

This invention discloses a genetically engineered bacterium producing high levels of L-homoserine, its construction method, and its applications, belonging to the field of biotechnology. The genetically engineered bacterium uses *Escherichia coli* W3110 as the substrate cell. By knocking out the metA, lysA, thrBC, pflB, ldhA, poxB, adhE, iclR, sthA, tdcC, lacI, and ptsG genes, and replacing the promoters of ppc, aspC, and gdhA genes with the inducible strong promoter Ptrc, and by performing site-directed mutagenesis on the thrA and asd genes, and simultaneously overexpressing the thrA*, pnhsd, asd, asd*, and rhtA genes using free plasmids, a recombinant strain HOM20 was constructed. This strain, fermented in a 5 L fermenter for 48 h, achieved an L-homoserine yield of 135.4 g / L and a sugar-acid conversion rate of 44%, significantly superior to existing technologies. This invention achieves directional carbon flow allocation, cofactor balance, feedback inhibition removal, and enhanced product efflux through multi-gene synergistic modification, and has broad prospects for industrial application.

The invention discloses a saccharomyces cerevisiae genetic engineering strain and application thereof. Based on a chassis strain SquMC13 with high squalene productivity, a sclareol synthesis route is modularly reconstructed, precursor carbon flow distribution is dynamically regulated and controlled, cell wall and membrane system steady states are adjusted, membrane lipid composition is adjusted, a cell cycle is intervened, and a product efflux system is enhanced, so that the problem of cytotoxicity caused by product accumulation is relieved to a certain extent. According to the invention, a plurality of saccharomyces cerevisiae engineering strains with high yield of sclareol are constructed, including Scl14, Scl24, Scl31, Scl38, Scl71 and Scl75, the result of the strain Scl75 is most prominent, the yield of sclareol fermented by a 250 mL shake flask is up to 4.1 g / L, efficient, stable and green biosynthesis of sclareol is realized, and a new strategy and theoretical basis are provided for microbial preparation of complex diterpenoid compounds.

This application can discover a histidine-excreting protein having the ability to excrete L-histidine or a variant thereof, and as a result of expressing this in a microorganism having the ability to produce L-histidine, the L-histidine production amount can be dramatically improved.

The application discloses a biosynthesis gene cluster of a polyene macrolide natural product mandimycin, and a natural product and application of the biosynthesis gene cluster, wherein the nucleotide sequence of the biosynthesis gene cluster is shown as SEQ ID NO. 1, and the compound structural formula of the natural product mandimycin and mandimycin B is shown as formula I and formula II. The natural product mandimycin can target fungal cell membrane phospholipid molecules, especially phosphatidylinositol, cause important ion efflux in fungal cells, and lead to fungal cell death. The natural product mandimycin and mandimycin B have strong in-vivo and in-vitro antibacterial activity and a broad antibacterial spectrum on various WHO-published multiple drug-resistant fungal key pathogens, including candida, aspergillus, cryptococcus, mucor and fusarium.

The invention relates to the technical field of biology, and particularly discloses a construction method and application of a recombinant Escherichia coli strain with high yield of bilirubin, and the construction method of the strain comprises the following steps: knocking out a heme precursor efflux gene in Escherichia coli, co-expressing the following modules in the Escherichia coli, introducing a gene gdha for enhancing coenzyme factor circulation, and carrying out expression to obtain the recombinant Escherichia coli strain with high yield of bilirubin. According to the method disclosed by the invention, heme precursor exclusion genes are knocked out in escherichia coli, meanwhile, heme oxygenase and biliverdin reductase are modularly assembled by adopting a protein covalent coupling technology, and the yield of bilirubin is increased by increasing synthesis of coenzyme.

The invention provides recombinant beauveria bassiana for catalyzing a high-concentration substrate as well as a construction method and application of the recombinant beauveria bassiana. Based on a metabolic engineering and efflux transport engineering strategy, cytochrome P450 enzyme or a transmembrane transport protein coding gene selected from an NPF protein family and an SWEET protein family is constructed into beauveria bassiana for producing R-2-(4-hydroxyphenoxy) propionic acid; the recombinant beauveria bassiana capable of stably catalyzing the conversion of the high-concentration R-2-phenoxypropionic acid into the R-2-(4-hydroxyphenoxy) propionic acid is constructed. Compared with a control strain, an experimental group has the advantages that the tolerance to the concentration of R-2-phenoxypropionic acid is obviously improved, and the fermentation period is shortened. The construction method provided by the invention provides an important target for transforming high-concentration R-2-phenoxypropionic acid into R-2-(4-hydroxyphenoxy) propionic acid under the catalysis of the transformed beauveria bassiana, and has an industrial application prospect.

The invention discloses a high-heme-yield escherichia coli engineering bacterium as well as a construction method and application thereof, and belongs to the technical field of synthetic biology. According to the engineering bacteria disclosed by the invention, eight genes in a heme C4 synthetic route are designed into two fusion multienzyme complexes, short peptide Linker is adopted for connection, escherichia coli preference codon optimization is performed, and the enzyme synergy efficiency is remarkably improved; and meanwhile, constructing a heme efflux protein recombinant plasmid, and co-transforming the heme efflux protein recombinant plasmid and the fusion multienzyme complex plasmid into an escherichia coli host to form a double-plasmid co-expression system. The engineering bacterium takes glucose / glycerol as a substrate and lactose as an inducer for fermentation, the shake flask yield of the heme reaches up to 865 mg / L and is increased by more than one time compared with the prior art, expensive intermediates such as glutamic acid / glycine do not need to be added, and the bottleneck of intracellular accumulation inhibition is effectively broken through. The fermentation product is directly extracted through the acetic acid solvent, the process is simple, the cost is low, the method is suitable for large-scale production of safe and high-purity heme, and a green biological manufacturing solution is provided for the fields of artificial meat, medicine and health care products.

The invention discloses application of lipoic acid trisulfide, and belongs to the technical field of medicines. The invention discloses application of lipoic acid trisulfide or salt, isomer and derivative thereof as a drug penetration enhancer or / and an efflux inhibitor. The invention also discloses a medicinal preparation which comprises a medicine penetration enhancer or / and an efflux inhibitor, and the medicine penetration enhancer or / and the efflux inhibitor is lipoic acid trisulfide or salt and isomer thereof. The lipoic acid trisulfide is scientific in design and ingenious in conception, it is found for the first time that the lipoic acid trisulfide or the salt, isomer and derivative thereof not only can improve the drug permeability, but also shows an excellent drug excretion inhibition effect, and has a dual regulation function. As a drug penetration enhancer or / and an excretion inhibitor, the compound can significantly improve the bioavailability of drugs.

The invention belongs to the technical field of gene engineering, and relates to an engineering strain with high yield of L-arginine as well as a construction method and application of the engineering strain. Corynebacterium glutamicum ATCC 21831 is used as an original strain, a growth-enhanced mutant strain MB5525 is obtained through ARTP mutagenesis, and an engineering strain 25Arg11 with high yield of L-arginine is finally obtained by further utilizing gene engineering strategies such as gene knockout, promoter replacement and exogenous gene insertion, and the preservation number is CGMCC No.35842. The invention further discloses a method for preparing the L-arginine mutant strain 25Arg11 with high yield of L-arginine. The strain system relieves feedback inhibition of arginine synthesis and strengthens key enzyme expression and product efflux, the L-arginine yield of 48 h shake flask fermentation reaches 41.5 g / L, the sugar acid conversion rate exceeds 40%, the L-arginine yield is improved by 10.5 times compared with the original strain ATCC 21831, antibiotics do not need to be added, the production efficiency is remarkably improved, and the production cost is reduced.

This invention relates to a liposome antibacterial and bacteriostatic synergist, its preparation method, and its application, belonging to the field of daily chemical products technology. The liposome antibacterial and bacteriostatic synergist provided by this invention comprises liposome contents, liposome wall material, dispersant, and water; by mass percentage, it includes the following components: 0.001-1% metal chelating agent, 2-50% dispersant, 0.01-5% efflux pump inhibitor, 0.1-10% liposome wall material, and the balance being water. The liposome antibacterial and bacteriostatic synergist provided by this invention addresses the source of bacterial resistance, significantly enhancing antibacterial and bacteriostatic effects through the synergistic combination of multiple components; simultaneously, it has a sustained-release effect, prolonging the duration of antibacterial and bacteriostatic synergistic action, and has high application value in daily chemical products.

This application can dramatically improve the L-histidine production amount as a result of discovering a histidine excretion protein having an L-histidine excretion ability or a variant thereof and expressing the same in a microorganism having an L-histidine production ability.

The invention relates to the technical field of biological medicines, and particularly discloses a method and a composition for promoting intestinal absorption of dihydroquercetin by using quercetin and application of the method and the composition, and the method comprises the following steps: jointly applying an effective amount of dihydroquercetin and an effective amount of quercetin serving as a synergist to an intestinal environment; wherein the quercetin plays a role through at least one of the following mechanisms: inhibiting the function or expression of P-glycoprotein in intestinal epithelial cells; the tight connection of intestinal epithelial cells is regulated. It is found that quercetin not only can effectively inhibit the excretion function of P-glycoprotein in intestinal epithelial cells, but also can enhance the integrity of intestinal barriers by down-regulating the expression level of the protein and up-regulating the expression of tight junction protein, so that intestinal absorption of dihydroquercetin is synergistically promoted from the multi-mechanism level; in addition, the composition can still maintain a good absorption promoting effect in an inflammatory environment, and shows a synergistic anti-inflammatory effect.