22 results about "Membrane lipids" patented technology

The invention discloses a functional lipid compound for nano-liposome wrapping and a preparation method, and relates to the technical field of functional lipid compounds, the functional lipid compound comprises (a) a polyphenol-lipid covalent conjugate which is composed of a polyphenol active unit selected from curcumin, dihydroquercetin or derivatives thereof, and (b) a lipid covalent conjugate which is composed of a polyphenols active unit selected from curcumin, dihydroquercetin or derivatives thereof and a polyphenols active unit selected from curcumin, dihydroquercetin or derivatives thereof; the conjugate is covalently linked to a phosphatidyl ethanolamine or cholesterol skeleton through a cleavable linking group, and the conjugate can be integrated into a nano-liposome membrane and has the functions of structural support and biological activity; (b) a microenvironment-responsive functional phospholipid, which is a phospholipid derivative having a functional group responsive to an inflammatory microenvironment specific stimulus modified on a hydrophilic head group or a hydrophobic chain of a phospholipid molecule, the specific stimulus being selected from local pH < = 6.5, reactive oxygen species (ROS) concentration > = 10 [mu] M or matrix metalloproteinase MMP-2 / 9 overexpression; and (c) a bionic exosome membrane lipid component, wherein the bionic exosome membrane lipid component comprises sphingosine-based glycolipid or sulfated cholesterol separated from the plant-derived exosome.

The present disclosure relates to the field of biotechnology, and in particular to method for modifying a high-yield L-lysine-producing strain engineering and application thereof. The present disclosure provides a recombinant strain obtained by knocking out the cbrB gene and / or the cbrC gene in the genome of E. coli. Fermentation of the recombinant strain can increase the yield and conversion rate of L-lysine and reduce the mortality rate of the strain during the fermentation process. The present disclosure has significant application value. Through experimental studies, it was found that these two genes have a synergistic effect on E. coli. L-lysine hydrochloride imposes osmotic stress resistance on the strains, and silencing the related gene proteins can alter the membrane lipid composition (increasing a proportion of unsaturated fatty acids), maintain membrane fluidity, improve tolerance to lysine hydrochloride, and reduce the mortality rate in the late stage of fermentation.

The invention relates to the technical field of biological medicine, and particularly discloses a macrophage membrane coated plateau encephaledema drug carrier and a preparation method and application thereof, and the macrophage membrane coated plateau encephaledema drug carrier is composed of a nanoparticle core and a macrophage membrane shell layer wrapping the core; the nanoparticle core comprises an ROS-responsive carrier material and carbon monoxide release molecules MnCO entrapped in the ROS-responsive carrier material; the content of phosphatidylserine in the shell layer of the macrophage membrane is not less than 5 mol% of the total phospholipid of the membrane. According to the invention, a bionic delivery system of ROS response type MnCO nanoparticles coated with a macrophage membrane is constructed, phosphatidylserine on the surface of the membrane is utilized to actively activate a microglial cell Trem2 receptor, a positive feedback cycle of targeting phagocytosis-CO release-Trem2 up-regulation is formed, and at the same time, fatty acid oxidative metabolism reprogramming is promoted by means of degraded membrane lipid, so that the biomimetic delivery system is used for preparing the ROS response type MnCO nanoparticles. And multi-mechanism synergistic efficient brain-targeted therapy is realized.

This invention discloses a method for isolating and preparing Chlorella exovesicles. Specifically, Chlorella, conventionally cultured to the early logarithmic growth phase, is induced to develop in a nitrogen-limited medium. The culture medium is then concentrated using a tangential flow filtration system. Finally, the concentrate is subjected to density gradient centrifugation with iodixanol. After centrifugation, components within the density range of 1.10–1.12 g / mL are collected to obtain the Chlorella exovesicle product. This invention achieves concentrated and precise collection of Chlorella exovesicles by regulating membrane lipids during the early induction culture of Chlorella, combined with TFF concentration and density gradient centrifugation. This method effectively eliminates impurities, achieving a recovery rate of over 60% and a purity of 2.56 × 10⁻⁶. 10 The particle / μg method provides an efficient, controllable, and scalable solution for the industrial-scale separation and preparation of microalgal exovesicles.

The invention discloses a photoresponsive antibacterial hydrogel, which comprises a photosensitizer, acrylamide, potassium 3-sulfopropyl methacrylate, chitosan quaternary ammonium salt, an additive and a cross-linking agent, and the structure of the photosensitizer (PD-Se) is shown in the specification. A photosensitizer (PD-Se) is added into hydrogel, the positive charge characteristic of QSA hydrogel remarkably improves the local enrichment concentration of PD-Se in thalli by enhancing the binding force with the bacterial surface, unsaturated fatty acid in a bacterial membrane lipid bimolecular layer is oxidized after photoinduced ROS is generated, guanine bases in a DNA double-helix structure are attacked at the same time, and therefore the bioactivity of the bacterial membrane lipid bimolecular layer is improved. The gel is endowed with photodynamic antibacterial ability, has an excellent sterilizing effect on escherichia coli, staphylococcus aureus and methicillin-resistant staphylococcus aureus, and can be used for preparing hydrogel dressing for wound repair.

This application relates to the field of plant genetic engineering technology, specifically disclosing the application of a sterol synthesis-related gene in the response regulation of plant salt tolerance. This application clarifies the sterol synthesis-related gene. SMT2 This study expands our understanding of the role of sterol biosynthesis in plant stress response by revealing the function of calcium signaling under salt stress; it also unveils a novel mechanism by which sterol-membrane lipid interactions regulate calcium signaling, providing a new perspective for research on plant salt stress signal transduction; furthermore, this application provides new salt tolerance gene resources. SMT2 Genes can be used for molecular breeding of salt-tolerant crops, to breed salt-tolerant crop varieties, or to develop salt-tolerant molecular markers.

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.

The invention belongs to the technical field of cell viability on-line discrimination, and particularly relates to a mass spectrum-based cell viability measurement method and a mass spectrum-based cell viability measurement system. The invention provides a label-free endogenous metabolite-based cell viability measurement scheme and a label-free endogenous metabolite-based cell viability measurement system, aiming at the defects that the prior art depends on an exogenous label and cannot be synchronously carried out on line with single cell mass spectrometry. The method comprises the following steps: acquiring continuous single cell metabolome data through single cell electrospray ionization mass spectrometry, identifying a single cell event and a time window by taking ubiquitous membrane lipid as a first characteristic ion, extracting an endogenous metabolite reflecting cell activity in the window as a second characteristic ion, and calculating a signal-to-noise ratio; generating an activity label according to a preset threshold value and counting the cell viability of the group, wherein the system correspondingly comprises a data acquisition module, an event identification module, a marker extraction module, a threshold value judgment module and a viability counting module. According to the invention, synchronous, on-line and label-free accurate measurement of the cell viability in single cell metabonomics analysis is realized, and exogenous interference and data deviation are effectively avoided.

The application discloses a preparation method of a flaky magnetic material for enriching exosomes. The flaky Fe3O4 magnetic material with high specific surface area is taken as a starting point, and a surface of the flaky Fe3O4 magnetic material is coated with silicon dioxide to enhance dispersibility and chemical stability of the flaky Fe3O4 magnetic material, and to provide controllable silicon hydroxyl reaction sites for subsequent surface chemical modification. On this basis, amino active groups are introduced to the surface of the magnetic material through 3-aminopropyl triethoxysilane (APTES), and DSPE-SS-PEG2000-CHO containing a disulfide bond structure is further covalently connected to the surface of the magnetic material. Due to a membrane lipid insertion mechanism, non-antibody-dependent capture of a lipid bilayer exosome can be realized. The flaky magnetic material disclosed by the application shows universality and high affinity advantages, and can realize high affinity capture of a lipid structure of an exosome.

The application discloses a kind of L-lysine high-yield production strain modification method and its application, belong to the field of bioengineering technology.The application obtains recombinant bacteria by knocking out CbrB gene and / or CbrC gene on the genome of escherichia coli, and the yield and conversion rate of L-lysine can be improved by fermenting the recombinant bacteria, and the mortality in the fermentation process of strain can be reduced.The application has important application value.The application finds through experiment that the influence of the two genes on escherichia coli has synergistic effect, L-lysine hydrochloride has osmotic pressure stress effect on strain, and silencing related gene protein can change membrane lipid composition (increase the proportion of unsaturated fatty acid), maintain membrane fluidity.Improve the tolerance to lysine hydrochloride, reduce the mortality in later fermentation stage.

This invention relates to the field of exosome delivery vector technology, specifically to a method and system for targeted delivery of CRB1 based on exosomes. The method includes acquiring a CRB1 inactivated cell recognition fragment, generating corresponding exosome image sequences, labeling membrane lipid insertion paths, constructing a targeted fusion conformation, completing the preparation of fused exosomes, and analyzing delivery distribution. This invention uses protein signal loss and nucleic acid breakage as dual indicators to screen cell states, combines image sequences to confirm the consistency of exosome origin, introduces membrane structure markers to define insertion boundaries, optimizes the fusion conformation through spatial structure pairing and charge polarity reversal, improves intermembranous chimerism matching and stability, and compresses the offset range based on the trajectory distribution of delivery particles on the target cell surface, enhancing target aggregation tendency and particle distribution density, thereby strengthening target recognition ability and membrane structure adaptation during delivery.

This invention discloses a feminine care oil capsule based on oil-soluble chimeric collagen and its preparation method, relating to the field of cosmetic technology. The oil phase contents include: 0.5–2.0 wt% oil-soluble chimeric collagen, 95–98 wt% plant oil-based carrier, 0.3–3.0 wt% biomimetic sebum membrane lipid composition, and 0.1–0.5 wt% antioxidant; wherein the biomimetic sebum membrane lipid composition is composed of ceramide, cholesterol, and free fatty acids in a molar ratio of (0.8–1.2):(0.8–1.2):(0.8–1.2). By constructing oil-soluble chimeric collagen molecules, which are stably dispersed in the plant oil-based carrier and self-assembled into nanomicelles, the technical problem that traditional water-soluble collagen cannot be applied to anhydrous oil phase systems is solved. Combined with the scientific formulation of the biomimetic sebum membrane lipid composition, it effectively enhances the vulvar skin barrier repair ability and moisturizing durability. With the specific preparation process and soft capsule dosage form, it achieves high stability of active ingredients, precise dosage, and no preservatives added.

The disclosure provides methods of preventing or treating cognitive impairment or a decline of cognitive function in a subject in need thereof, the method comprising administering an effective amount of at least one compound to the subject, wherein administration of the compound reduces cellular and / or plasma membrane lipid content.

The invention provides a non-ribosome polypeptide compound as well as a synthetic gene cluster BNP37 and application thereof, the structural sequence of the polypeptide compound is X0-X1-X2-X3-X4-X5-X6-X7-X8-X9-X10-X11, the polypeptide compound is a linear peptide or a cyclic peptide, and the cyclic peptide is a lactam cyclic peptide formed by connecting any one of X1, X3 and X5 with X11, or a lactam cyclic peptide or a lactone cyclic peptide formed by connecting X2 with X11. The compound disclosed by the invention can cause discharge of important ions in bacterial cells by targeting Gram-negative bacterium outer membrane lipid A and Gram-positive bacterium teichoic acid, so that bacterial death is caused. The compound disclosed by the invention has strong in-vivo and in-vitro antibacterial activity on a plurality of multi-drug-resistant gram-negative pathogenic bacteria such as escherichia coli, klebsiella pneumoniae, acinetobacter baumannii, pseudomonas aeruginosa, enterobacter cloacae and neisseria gonorrhoeae and a plurality of multi-drug-resistant gram-positive pathogenic bacteria such as staphylococcus aureus and enterococcus faecium.

The invention discloses preparation and application methods of a nutrient solution for preventing and treating low-temperature freeze injury of tomatoes, and belongs to the technical field of agricultural fertilizers. The nutrient solution for preventing and treating the low-temperature freezing injury of the tomatoes is prepared from the following raw materials in parts by mass: 5 to 10 parts of triacontanol, 3 to 10 parts of gamma-aminobutyric acid, 10 to 25 parts of proline, 3 to 7 parts of linolenic acid, 30 to 40 parts of potassium nitrate, 5 to 10 parts of potassium silicate, 15 to 20 parts of calcium superphosphate, 20 to 30 parts of calcium chloride, 1 to 5 parts of zinc sulfate, 1 to 5 parts of copper sulfate, 5 to 10 parts of manganese sulfate and 150 to 250 parts of water. The nutrient solution for preventing and treating the low-temperature freezing injury of the tomatoes is beneficial to solving the problem that the yield and quality of the tomatoes are easily influenced by low-temperature stress, and can promote plants to synthesize antifreeze proteins and osmotic regulators, reduce the membrane lipid phase transition temperature and greatly improve the stress resistance of the plants.

The present application relates to the field of plant physiology and biomarker, and particularly relates to a cell membrane lipid marker combination for characterizing cold tolerance of citrus fruits and application in detection. The present application provides a set of cell membrane lipid marker combination for characterizing cold tolerance of citrus fruits, which comprises 39 kinds of membrane lipid components such as PC(O-38:5), ShexCer(35:0;20), PE-Cer(41:6;20), LPE(36:3), PC(32:0), TG(16:0_18:0_18:1), LPC(20:3) and the like. The process for extracting, purifying and detecting the membrane lipid components of citrus fruits is established, and a cell membrane extraction and detection kit convenient for small sample operation is developed, so as to provide a rapid and simple evaluation method for breeding of cold-tolerant varieties of citrus fruits and selection of reasonable storage temperature after harvesting.

The invention relates to the technical field of medical treatment, and particularly discloses a red breaking liquid for bloody body fluid cell wax blocks. The red breaking liquid is prepared from absolute ethyl alcohol and distilled water, and the volume concentration of the absolute ethyl alcohol is 20%-30%; according to the method, the ethanol aqueous solution in a specific concentration range is adopted as a splitting system, efficient and selective splitting of the red blood cells in the bloody body fluid is realized, and cell membranes of the seedless red blood cells can be quickly destroyed by utilizing the dissolution effect of ethanol on cell membrane lipid and the hypotonic characteristic of the solution, so that contents of the seedless red blood cells are released and are easily eluted. Meanwhile, the morphological integrity and cell membrane antigenicity of nucleated cells (including tumor cells) can be protected to the greatest extent, and the problem of cell damage or antigen shielding possibly caused by a conventional hemolytic agent is avoided.

The invention provides a yarrowia lipolytica engineering strain with high yield of beta-carotene and construction of the yarrowia lipolytica engineering strain, and belongs to the technical field of synthetic biology and metabolic engineering. According to the invention, a multi-copy geranyl-geranyl pyrophosphate synthase gene, a compartmentalized localization expression beta-carotene synthetic pathway related enzyme gene, a diacylglycerol acyltransferase gene, a cell cycle regulation transcription factor, an oxidative stress regulation related gene, and a cell wall and membrane lipid homeostasis regulation related gene are integrated; and regulating foreign protein folding and expression related genes to obtain the yarrowia lipolytica engineering strain for efficiently biosynthesizing beta-carotene by taking glucose as a substrate. The yield of beta-carotene of the constructed yarrowia lipolytica engineering strain is high, the yield at the shake flask level can reach 3253.2 mg / L, and the yield can be increased to 26.5 g / L when fed-batch fermentation is carried out on a 5L scale. The method has great practical significance and economic value for industrial and commercial application of high-value terpenoid products.

The invention relates to membrane lipid coated nanoparticles and methods of use thereof. Disclosed herein are nanoparticles and methods of making the same, the nanoparticles comprising a virus-containing inner core; and an outer surface comprising a cell membrane derived from cells. The virus is an oncolytic virus, and the cell membrane is derived from, for example, red blood cells.

Disclosed is a process of making a nanoparticle comprising an inner core comprising a virus and an outer surface comprising a cellular membrane derived from a cell via extrusion.

The application provides a fruit tree dormant branch cold resistance comparison method, relates to the technical field of fruit tree cultivation, and comprises the following steps: alternately performing polarization mode operation and impedance mode operation on the same detection site of the fruit tree dormant branch; when the polarization mode operation is performed, first wave band laser and second wave band laser are emitted to the detection site at a preset incident angle, and a transmitted light intensity data group is obtained; when the impedance mode operation is performed, a sweep frequency current is injected into the detection site, and an impedance component data group of a characteristic frequency point is collected; the intercellular ice crystal density is calculated according to the transmitted light intensity data group; the membrane lipid phase shift angle is calculated according to the impedance component data group; when the intercellular ice crystal density is greater than an activation threshold value, the ice crystal-membrane lipid synergy ratio is calculated based on the intercellular ice crystal density and the membrane lipid phase shift angle; the cold resistance synergy index is calculated according to the change rate of the intercellular ice crystal density and the membrane lipid phase shift angle; and the cold resistance grade is determined according to the cold resistance synergy index value.

The invention belongs to the technical field of bioengineering, and discloses a method for rapidly preparing an archaea cell membrane lipid intermediate product 2, 3-di-O-geranyl geranyl-glycerol (DGGGOH). The method comprises the following steps: constructing engineering escherichia coli for expressing archaea membrane lipid synthesis genes (crtE, GGPPS, G1PDH, GGGPS and DGGGPS) and mevalonic acid (MVA), and carrying out induced fermentation, cell disruption, organic solvent extraction and semi-preparative C18 reversed-phase chromatographic column purification to realize efficient preparation of DGGGOH. The method provided by the invention solves the technical bottlenecks of tedious operation steps, low yield, low recovery rate and the like of traditional chemical synthesis and other microbial fermentation preparation of DGGGOH, and provides reliable technical support for archaea membrane lipid research and large-scale production of DGGGOH.