170 results about "Efflux" patented technology

The invention belongs to the technical field of genetic engineering and metabolic engineering, and discloses an escherichia coli genetically engineered bacterium for fermentation production of L-histidine, a method and application of the escherichia coli genetically engineered bacterium for fermentation production of L-histidine. The escherichia coli genetically engineered bacterium is prepared by taking wild escherichia coli MG1655 as a starting strain, and knocking out a gene lacI and a gene purR on a genome; integrating the gene prs, the gene zwf and the gene gnd; the method comprises the following steps: integrating genes hisG, hisD, hisB, hisC, hisA, hisF / H and hisIE; and a gene cgl2458 is integrated. According to the invention, a molecular biological technology is utilized to integrate histidine operon in a serratia marcescens mutant strain with high histidine yield into an escherichia coli genome, and an escherichia coli genetically engineered strain with high histidine yield is obtained by enhancing precursor PRPP supply, histidine efflux and other strategies, so that the problems of thick fermentation liquor, high histidine yield and high histidine yield can be solved. And the method has a relatively good industrial application potential.

The invention provides an NMN efficient synthesis strain and a construction method and production application thereof, and belongs to the technical field of engineering bacteria. According to the invention, firstly, an NMN synthesis route taking NAM as a substrate is constructed in escherichia coli, and specifically, NadV and PrsD128A are introduced into the escherichia coli, so that the NMN synthesis flux is improved; pnuC is introduced to promote the external arrangement of the NMN; the method comprises the following steps: knocking out PncC, NadR, UshA, NudC and MazG; pfkA and TalA are knocked out to improve the carbon flux of the pentose phosphate pathway. GDH1 and GDH2 are heterologously expressed in engineering bacteria to establish a reducing power balance system, the reducing power balance system is used for converting NADPH excessively accumulated in an NMN synthesis route into NADH, and meanwhile, an esaR-esaI group response element is introduced to dynamically regulate and control the system. The engineering strain constructed by the method can accumulate 3.0 g / L of NMN after 24-hour shake flask fermentation.

The invention relates to the technical field of antibiotic mushroom dreg treatment, in particular to a method for reducing antibiotic mushroom dreg. The method comprises the following steps: drying granular antibiotic mushroom dregs until the moisture content is 10-28% by adopting a hot air drying mode; the temperature of the hot air drying is 52-58 DEG C. According to the method, hot air drying is adopted, the temperature condition of hot air drying is limited, the problems caused by incineration treatment in the antibiotic mushroom dreg treatment process can be solved, the antibiotic mushroom dreg reduction efficiency is high, and the reduction rate reaches up to 53%. The reduction equipment is used for treating the antibiotic mushroom dregs, the hot air drying process is totally closed, no waste gas is discharged, the chemical properties of the mushroom dregs are not changed in the reduction process, no secondary pollution is generated, the quantity of the air-dried mushroom dregs is small, the mushroom dregs are easy to package, store, transfer and follow-up further harmless incineration standard treatment, and the ecological environment and human health are protected. The strict environmental protection control requirement is met, and the economic benefit is very considerable.

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 invention discloses a preparation method of macrophage targeting ASD nano particles, a prepared nano carrier and application of the nano carrier, ASD active molecules can be controllably released under the stimulation of an intracellular microenvironment (high ROS and low pH), inflammation is eliminated, meanwhile, lipid efflux is increased, and therefore effective intervention on atherosclerosis is achieved. The method comprises the following steps: (1) synthesizing a 3-acrylamido phenylboronic acid monomer B; (2) synthesizing a phenylboronic acid polymer pB; (3) synthesizing a conjugate PB-ASD of a phenylboronic acid polymer pB and akebiaquinata saponin D; (4) synthesizing a mannose modified polymer Man-PEG (Polyethylene Glycol)-DSPE (Distearoyl Sulfonate And (5) blending the Man-PEG-DSPE and the conjugate PB-ASD, and preparing the macrophage targeting ASD nano particle ASD (at) DPM NPs in an oil / water system, so as to obtain the macrophage targeting ASD nano particle ASD (at) DPM NPs.

The invention relates to the technical field of microbial metabolism engineering, and discloses a genetically engineered bacterium for producing L-ornithine as well as a construction method and application of the genetically engineered bacterium. According to the genetically engineered bacterium provided by the invention, putrescine synthesis pathway genes speC, speF and argF are knocked out in a genome of the genetically engineered bacterium, a dynamic regulation gene argI is achieved, an L-ornithine synthesis pathway gene cluster derived from corynebacterium glutamicum is over-expressed at a mazG site, a gene argG is knocked down, transcription of a proline pathway gene proB is controlled at a temperature on the genome, and the gene engineering bacterium is obtained. An efflux protein coding gene lysE which is started by a promoter PLtetO-1 and is derived from corynebacterium glutamicum is inserted into a trpR site, and an original promoter of an argO gene on a genome is replaced by the promoter PLtetO-1, so that synthesis and degradation pathways of L-ornithine are reasonably optimized, and expression of a competitive pathway and an efflux-related gene is controlled through temperature change, so that the yield of L-ornithine is increased, and the yield of L-ornithine is increased. In the fermentation process, normal growth of thalli can be maintained without adding arginine, and finally high yield of L-ornithine is achieved.

The invention relates to a recombinant expression vector for synthesizing outer membrane protein of cyanidin-3-O-glucoside, a recombinant microorganism and a preparation method of the recombinant microorganism. The recombinant expression vector contains a gene sequence for coding the outer membrane protein. The outer membrane protein is used for constructing a recombinant expression vector and a recombinant microorganism, efflux transport of cyanidin-3-O-glucoside is promoted, and the yield of cyanidin-3-O-glucoside is increased.

The invention provides a genetically engineered bacterium for producing R-2-(4-hydroxyphenoxy) propionic acid at high yield as well as a construction method and application of the genetically engineered bacterium. Based on metabolic engineering and efflux transport engineering strategies, transmembrane transport protein coding genes selected from an NPF protein family and an SWEET protein family are constructed into beauveria bassiana capable of producing R-2-(4-hydroxyphenoxy) propionic acid, and genetic engineering bacteria capable of stably and highly producing R-2-(4-hydroxyphenoxy) propionic acid are constructed. Compared with a control strain, an experimental group has the advantages that the yield of R-2-(4-hydroxyphenoxy) propionic acid subjected to liquid fermentation is remarkably increased, and the fermentation period is shortened. The method for constructing the high-yield R-2-(4-hydroxyphenoxy) propionic acid gene engineering strain by transforming the beauveria bassiana on the basis of efflux transport engineering provides an important target for efficiently producing the R-2-(4-hydroxyphenoxy) propionic acid by transforming the beauveria bassiana, and has an industrial application prospect.

Provided herein are genetically modified microorganisms comprising a nonsense mutation in a gene encoding an efflux pump or import protein, and a vector encoding a suppressor tRNA that enables translation of the efflux pump or import protein, mitigating the effect of the nonsense mutation. Also provided are methods of producing a vector or markerless DNA using the genetically modified microorganisms provided herein.

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.

Provided herein is a method of administering levoketoconazole, or a pharmaceutically acceptable salt thereof, to a subject in need thereof, wherein the subject is also being administered a multidrug and toxin extrusion transporter 1 (MATE1) substrate or an organic cation transporter 2 (OCT2) substrate.

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 discloses saccharomyces cerevisiae engineering bacteria for efficiently synthesizing mogroside V on the basis of cytoplasm and lipid droplet double-cell area compartment and a construction method of the saccharomyces cerevisiae engineering bacteria. The construction method comprises the following steps: integrating truncated 3-hydroxy-3-methylglutaryl coenzyme A reductase tHMG1, pentenyl pyrophosphate isomerase IDI1, epoxy squalene cyclization enzyme ERG1, squalene synthetase ERG9, choline kinase ScCK, isopentenyl phosphokinase AtIPK, cucurbitadienol synthetase SgCDS, cyclic epoxy hydrolase SgEPH3, cytochrome P450 enzyme CYP87D18 and cytochrome P450 enzyme reductase AtCPR1 at the site of a saccharomyces cerevisiae genome GAL80; an ABC efflux protein PDR11, a glycosyl transferase UGTMG1, a sucrose synthase Susy and a glycosyl transferase SgUGT94-289-3 are integrated at a site Exg1 of a saccharomyces cerevisiae genome. The yield of mogroside V produced by shake flask fermentation of the saccharomyces cerevisiae engineering strain provided by the invention reaches 96.3 mg / L, so that mogroside V is efficiently synthesized from the beginning in the saccharomyces cerevisiae, and the saccharomyces cerevisiae engineering strain has important practical significance for promoting sustainable development of the mogroside industry.

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.

The invention provides a method for recycling mushroom dregs for producing long-chain dibasic acid. The method comprises the following steps: (1) pre-treating the mushroom dregs: separating the fermented mushroom dregs for producing the long-chain dibasic acid to obtain mushroom sludge; (2) releasing substances in the mushroom dregs: taking the mushroom sludge in the step (1), adding hydrolase and an activating agent, and respectively carrying out heat preservation twice at 35-50 DEG C and 52-70 DEG C; and (3) fermenting the treated mushroom dregs: using the mushroom dregs treated in the step (2) as a culture medium component to replace or partially replace a nitrogen source in the mushroom dregs for fermentation. A nitrogen source of the fermentation culture medium is replaced or partially replaced by the mushroom dregs, and after treatment of the method, protein is released in a high proportion, so that resource reutilization of the mushroom dregs is realized, and meanwhile, the problems of difficulty in discharging the mushroom dregs, high treatment cost and the like are solved.

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 relates to a cyclic peptide for inhibiting a drug-resistant bacterium AcrB protein as well as a delivery vector and application of the cyclic peptide. The amino acid sequence of the cyclic peptide comprises any one of sequences as shown in SEQ ID No.1-SEQ ID No.15. The invention discloses a cyclic peptide inhibitor for reversing the drug resistance of antibiotics. The method comprises the following steps: firstly, designing and screening out cyclic peptide capable of forming high affinity with AcrB protein; secondly, the delivery carrier entraps the cyclopeptide to a bacterial membrane to cause membrane disturbance, the cyclopeptide enters the bacterial membrane to be combined with AcrB on an inner membrane to inhibit antibiotic excretion, the sensitivity of bacteria to the antibiotics is enhanced, and the MIC of the antibiotics is reduced.

The present invention belongs to the field of biomedicine technology, and specifically relates to a nanogel that promotes intestinal absorption and its preparation method and application. The nanogel that promotes intestinal absorption provided by the present invention is a nanogel that promotes intestinal absorption through Ca 2+ Cross-linked selenized mercapto sodium alginate, as an active factor delivery system, can not only protect the active factors from being degraded by gastric acid, but also achieve intestinal targeting through intestinal mucus anchoring and inhibit the efflux of P-glycoprotein on the cell membrane of intestinal mucosal epithelial cells, thereby achieving intestinal targeted delivery of active factors and promoting cellular absorption of active factors. It is of great significance for improving the bioavailability of active factors and has broad application prospects in the creation of functional foods and the research and development of intestinal targeted drugs.

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 discloses an AcrB efflux pump inhibitor with a membrane permeabilization effect as well as a preparation method and application thereof. The AcrB efflux pump inhibitor is a solvent compound, an enantiomer, a diastereoisomer, a tautomer or a mixture of a compound with a structure as shown in a formula I or pharmaceutically acceptable salt of the compound, wherein R is C6-C16 straight chain or branched chain alkyl, alkenyl, ester group, amide or substituted phenyl; x is N or C; y is N or C. The compound provided by the invention has better efflux inhibition activity, and the minimum inhibitory concentration can be reduced by 64 times when the compound is combined with minocycline for use.