10results about How to "Maintain genetic stability" patented technology

The invention belongs to the technical field of gene engineering, and discloses a schizochytrium limacinum gene engineering strain capable of efficiently producing EPA (Eicosapentaenoic Acid). The gene engineering strain is obtained by replacing key catalytic structural domains orfA, orfB-KSB / CLF in a schizochytrium limacinum PKS pathway with corresponding functional domains in a heterologous EPA type PKS pathway. The gene engineering strain can improve the proportion of polyunsaturated fatty acid in the gene engineering strain, especially eicosapentaenoic acid. EPA generated after fermentation of the obtained schizochytrium limacinum genetic engineering strain orfA:: PfaA and KSB / CLF:: PfaC reaches 4.24% and 10.19% of the total grease content respectively, the EPA content is increased by 2.52 and 7.47 times respectively, and compared with an existing schizochytrium limacinum wild type strain, the EPA yield is greatly increased, which shows that the method provided by the invention has extremely high application potential.

The invention relates to motherwort cultivation. The leonurus japonicus rooting induction method is characterized by comprising rooting induction: when adventitious buds grow to 1-3 cm, the adventitious buds are cut off from explants and transferred into a rooting culture medium to be cultured, the rooting culture medium takes an MS culture medium as a basic culture medium, and IBA with the concentration of 0.1 mg.L <-1 > is added into the rooting culture medium. The components of the culture medium are selected, and the rooting rate of the selected rooting culture medium is high.

A method for cryopreservation and recovery of larch olgensis embryogenic callus relates to the biotechnology field of forest breeding, and comprises the following steps: selecting an embryogenic cell line induced by immature seeds of larch olgensis, and subculturing the embryogenic cell line for 3-5 days to obtain embryogenic callus as a standby material; carrying out gradient pre-culture at the molar concentrations of 0.2 mol / L and 0.4 mol / L in sequence, wherein the culture is carried out at each concentration for 20-48 hours; after pre-culture, putting the embryogenic callus into a freezing tube, and adding a sterile freezing protection solution; and putting the freezing pipe into a programmed cooling box for programmed cooling, and immediately putting the freezing pipe into a liquid nitrogen biological container for storage. The method disclosed by the invention is simple and convenient in operation steps and obvious in effect, the subculture age limit of the larix olgensis embryonic callus is slowed down, and relatively good cell viability and development potential in the initial stage of induction are maintained, so that the occurrence of variation is effectively reduced, manpower and material resources consumed by long-term subculture materials can be saved, and the production cost is reduced. The method is of great significance to theoretical and practical application research of larix olgensis.

This invention discloses a drug-resistant Ewing sarcoma cell line, named human Ewing sarcoma cell ES 003, which was deposited at the China Center for Type Culture Collection on March 10, 2026, with accession number CCTCC NO: C202642. The cell line exhibits doxorubicin resistance; specifically, doxorubicin has an IC50 of [missing information - likely referring to an IC50 value] against the human Ewing sarcoma cell ES 003. 50 Above 5μM.

The invention discloses a silage corn crossbreeding method, and belongs to the technical field of corn breeding. The method is realized through three steps of selfing, hybridizing and backcrossing of the Jinling silage 17. Different pollination modes are used in odd-numbered days and even-numbered days, and artificial pollination and bee pollination are combined, so that the success rate and efficiency of pollination are ensured, and the complexity and labor intensity of manual operation are reduced. By spraying the liquid fertilizer Q, comprehensive nutrition required by corn growth is provided, and particularly, the human excreta subjected to high-temperature treatment and the combination of various nutritional ingredients can effectively promote healthy growth of plants and increase the yield. The fresh weight yield of the hybrid seeds treated by the method disclosed by the invention is 105877-120002 kg / hm < 2 >, the yield is increased by 21.50%-29.19%, the dry matter yield is 34007-35983 kg / hm < 2 >, the yield is increased by 20.89%-22.93%, and the economic benefit is remarkable.

The application discloses a novel polyhydroxyalkanoate (PHA) polymerase (PhaC) which can efficiently polymerize the activated monomer 6-hydroxyhexanoate-CoA (6HHx-CoA) of 6-hydroxyhexanoate (6HHx). The PhaC is co-expressed with a CoA ligase AlkK, and can synthesize poly-epsilon-caprolactone (PCL) from the direct precursor sodium 6-hydroxyhexanoate in a halomonas sp. Halomonas which has deleted endogenous beta-ketothiolase (PhaA), acetoacetyl-CoA reductase (PhaB), PhaC and enoyl-CoA hydratase (FadB).

The application belongs to the technical field of plant cultivation and particularly relates to a Blumea riparia growth medium, a tissue culture medium, a tissue culture method and application. The Blumea riparia growth medium takes MS medium as a basic medium and further comprises 0.2-0.3 mg / L NAA, 0.08-0.16 mg / L DA-6, 10 mg / L vitamin C, 20 mg / L myo-inositol, 30 g / L sucrose and 6 g / L agar. DA-6 and NAA are jointly applied to improve the rooting efficiency, root length and plant height of Blumea riparia. The Blumea riparia germplasm with high content of levorotatory borneol is used as an explant to carry out tissue culture and seedling raising, the Blumea riparia tissue culture seedling has high content of levorotatory borneol, and Blumea riparia stable genetic good seedlings can be produced.

The application provides a recombinant bacillus subtilis strain capable of efficiently degrading ethanol in response to ethanol and anaerobic environment and a construction method thereof. The strain takes bacillus subtilis as a chassis, and a cascade amplification system is constructed. An induction control box is driven by an ethanol or anaerobic response promoter to express T7 RNA polymerase; and a functional expression box is driven by a T7 promoter to express ethanol dehydrogenase and acetaldehyde dehydrogenase genes in series. The application takes flagellum synthesis genes flM as integration sites, realizes chromosomal integration and flM knockout of double expression boxes through homologous recombination, and obtains the recombinant strain bacillus subtilis DE-02. The strain can intelligently respond to ethanol or anaerobic signals in the intestinal tract, efficiently express ethanol degradation enzymes through a T7 cascade system, completely oxidize ethanol into non-toxic acetic acid, and has the advantages of motion loss, no antibiotic dependence, genetic stability and the like, and is suitable for preparing oral alcoholism-relieving probiotic preparations or functional foods.

The invention belongs to the technical field of mechanical structures, and particularly relates to a grain tank device of a combine harvester, which comprises a tank body, a grain outlet cylinder, a gantry guide mechanism and a driving mechanism. The portal frame guide mechanism comprises a portal frame base, a left portal frame, a right portal frame and a grain tank support. The left side door frame and the right side door frame are arranged in parallel and are vertically and fixedly connected with the door frame base respectively; the two ends of the grain tank support are slidably connected with the left door frame and the right door frame respectively, and the tank body is installed on the grain tank support. The driving mechanism is installed on the portal guide mechanism and cooperates with the portal guide mechanism to control the box body to ascend or descend. One end of the grain outlet cylinder is rotationally communicated and connected with one side of the bottom of the box body; the flashboard assembly is arranged at the other end; a rotary drum handle is arranged on the side face of the grain discharging drum. According to the technical scheme, the grain breakage rate is reduced by adopting a brand-new structural design; the grain discharging barrel can flexibly rotate to realize accurate grain unloading; the unloading process is optimized by the box body structure and the driving mechanism; the design of the flashboard assembly, the pulley and other assemblies provides convenient control experience.

The invention provides an induction method and an induction culture medium for inducing Helleborus thibetanus petioles to regenerate adventitious buds, and solves the technical problem of low efficiency of inducing sprouted adventitious buds of Helleborus thibetanus rhizomes or overground stems in the prior art. A method for inducing regenerated adventitious buds of helleborus thibetanus petioles comprises the steps that petiole explants are disinfected and sterilized and transplanted to a regenerated adventitious bud induction culture medium, and the regenerated adventitious bud induction culture medium comprises 6-benayl aminopurine, forchlorfenuron, zeatin, 6-furfuryl aminopurine, indolebutyric acid, multivitamin tablets, a coagulator, cane sugar and a nutrient culture medium. According to the method, the helleborus thibetanus petioles are used as explants, adventitious buds can be efficiently induced, a helleborus thibetanus plant regeneration technical system is established, rapid propagation, high regeneration efficiency and rich explant sources are realized, meanwhile, a mature, stable and efficient helleborus thibetanus regeneration system is established, and the method has important significance on transgenic breeding of helleborus thibetanus.