49results about How to "Improve mutagenesis efficiency" patented technology

The atmospheric cold plasma microbe mutagenesis method belongs to the field of microbe mutagenesis technology, and features the cold plasma mutagenesis of microbe strain to denature. The microbe strain may be pronucleus microbe or eukaryotic microbe; the atmospheric cold plasma may have discharging medium of air, nitrogen or helium with discharge period of 10 s to 10 min, applied voltage of 1-100 kV and frequency of 0-15 MHz; and mutagenesed microbe may be in suspension or plate. Compared with other physical and chemical mutagenesis method, the present invention has the advantages of simple apparatus, low cost, operation safety and high mutagenesis effect, and may be applied widely in industrial microbe breeding.

The invention discloses a method for breeding microorganisms by plasma-induced mutation, which radiates microorganisms to be induced to mutate with a plasma jet flow that uses neutral active particles as acting particles to obtain mutated microorganisms. The method in which the neutral active particles in the plasma jet flow play a main induction role has the advantages of: ensuring the high activity of forward mutant strains and the high capability and genetic stability of produced target products, reducing mutagenesis period and improving mutagenesis efficiency, inducing a great variety of microorganisms such as prokaryotic microorganisms, eukaryotic microorganisms and archaebacteria in form of microbial community, bacterial suspension or spore suspension, simplifying experimental operation by avoiding culturing the processed microorganisms in the dark, having the characteristics of simple, safe and pollution-free whole operation, low equipment and experiment cost and the like and having great potential role in the field of industrial microorganism induced mutation breeding.

The invention relates to a chemical mutation breeding technology in the field of biotechnologies, and particularly relates to an in-vitro sodium azide (NaN3) mutation breeding technology of dendranthema morifolium. The in-vitro NaN3 mutation breeding technology comprises the following steps of: performing culture in vitro on an immature stem, a stem tip or a leaf of the dendranthema morifolium to form an aseptic seedling; processing the stem tip and a stem segment of the aseptic seedling, which are taken as explants, by sodium azide (NaN3) in a breeding process to carry out induced mutation; rooting and transplanting a test-tube plantlet; and finally breeding excellent mutant in a field at a flowering phase. The in-vitro sodium azide (NaN3) mutation breeding technology can effectively overcome the obstacle of breed improvement of a clonal plant and the constraints of low bud-variation frequency and small mutational range under natural conditions, can be used for obtaining the excellent mutant within a short period of time, ensures high induced mutation efficiency, and has an important value to the genetic improvement of asexual propagation of the dendranthema morifolium with medicinal and ornamental values.

The invention relates to a production technology for fermentatively producing sodium hyaluronate by utilizing bacterium. The production technology comprises the following steps of: using streptococcus equi subsp. zooepidemicus (Streptococcus Zooepidemicus) as an original strain; mutagenizing by virtue of nitrosoguanidine, and also mutagenizing by virtue of a protoplast in the presence of ultraviolet rays; introducing a special culture medium; carrying out submerged fermentation to produce high-output hyaluronic acid; and then carrying out a relative separation and purification technology to obtain a high-purity sodium hyaluronate product. According to the production technology for fermentatively producing the sodium hyaluronate by utilizing the bacterium, under the culture conditions that the culture temperature is 32 to 38 DEG C, the pH (Potential Of Hydrogen) of fermentation liquor is maintained within the range of 5.0 to 9.0, and a fermentation tank is at speed of stirring of 150 to 600rev/min, the output of the hyaluronic acid is greatly increased; and the production technology is suitable for being applied to industrial production.

The invention discloses a Paecilomyces thermophila mutant strain and a mutation induction method and application thereof. The mutation induction method includes: Paecilomyces thermophila screened from high-temperature-fermented compost and used for producing high-temperature-resistant and acid-resistant glucose oxidase is used as the original strain, protoplast ultraviolet and ethyl methane sulfonate compound mutation induction is performed, and the screened strain is subjected to budding spore diethyl sulfate-microwave compound mutation induction to obtain the Paecilomyces thermophila mutant strain. The Paecilomyces thermophila mutant strain is preserved in China General Microbiological Culture Collection Center on January 11th, 2016, and the preservation number of the mutant strain is CGMCC No. 13182. Compared with a conventional mutation induction method, the mutation induction method has the advantages that the method is high in efficiency and simple in fast in screening, the productivity of the mutant strain is high, the yield of the mutant stain is 277.65% of that of the Paecilomyces thermophila original strain, fermentation liquor enzyme activity reaches 185U/ml, production cost is lowered, and the glucose oxidase produced by the mutant strain is good in high-temperature resistance and acid resistance and can be used as feed enzyme applied to feed industry.

The invention discloses a method and a device for mutagenizing a biomaterial and belongs to the field of biotechnology. The method comprises the following steps of 1, coating a solid medium with cells to be treated, and 2, mutagenizing the coating cells which comprise microbial cells and suspension cells of animals and plants. The method can substantially improve mutagenesis efficiency and screening efficiency and is conducive to mutagenesis breeding adopting automatic high-flux experimental equipment.

The invention belongs to the field of microbial fungi, and relates to a Cordyceps militaris strain capable of producing heat-resistant proteinase and cordycepin at high yield and application thereof. The strain is prepared by the following steps: selecting a Cordyceps militaris wild-type strain newly separated from the natural world as the initial strain, carrying out composite mutagenization under the actions of Cordyceps militaris protoplast nitrosoguanidine and ultraviolet light, separating and screening to obtain the strain. The strain was collected by China General Microbiological Culture Collection Center on November 11th, 2016; the collection number is CGMCC No.13179; the strain is named HYCM12; and the classification designation is Cordyceps militaris. After the strain is subjected to deep liquid ventilation fermentation, the cordycepin content reaches 2.89 g/L, and the heat-resistant proteinase activity reaches 5326U/ml. Meanwhile, the method is simple to operate and easy to implement, has the advantages of short period, abundant and accessible raw material sources, low cost, no environmental pollution, low equipment and reagent price and the like, and is convenient for large-scale production.

A method for producing mutant of hemerocallis middendorffii by in vitro mutagenesis of ethyl methane sulfonate (EMS) amis to provide an EMS in vitro mutagenesis method for breed improvement of hemerocallis and creation of new germplasm resources and to obtain a target variant strain. The method for producing the mutant of the hemerocallis middendorffii by the in vitro mutagenesis of the ethyl methane sulfonate adopts the 1 to 2cm flower buds in normal growth and development state of the hemerocallis middendorffii as materials, inoculates callus induced by taking ovaries as explants to a differential medium, and green buds are differentiated. After the callus with buds is subjected to differentiation culture for 10 days, a callus block is treated with EMS semi-lethal dose at a concentration of 0.75-1.0 percent (w/v). The treated callus is inoculated to the differentiation medium for differentiation culture to obtain regenerated plants. When the regenerated plants grow to 1 to 2 cm high, the regenerated plants are cut down from the callus and put in a subculture medium to conduct subculture for 15 days, hemerocallis septoria tritici toxin semi-lethal dose at a concentration of 40 percent (v/v) is taken as directional selection pressure for stress screening, and disease-resistant mutant plants are obtained.

The invention discloses a method for breeding an high-yield ascomycin strain by performing femtosecond laser mutagenesis on streptomyces hygroscopicus ascomycota subspecies and a culture medium preparation method; the method comprises the following steps: at room temperature, mixing mature slant spores of the streptomyces hygroscopicus ascomycota subspecies (ATCC14891) and sterile water to obtain monospore suspension containing 106-107 spores per milliliter; irradiating the spore suspension for 1-10 min by using the titanium sapphire femtosecond laser with centre wavelength of 800 nm, pulse width of 150 fs and frequency of 76 MHz under a irradiation power of 10-30m W; properly diluting the spore suspension, coating on a solid panel to culture, then screening by using a shake flask to obtain a high-yield ascomycin mutation strain. The method provided by the invention has the advantages that the used femtosecond laser mutagenesis method is feasible and safe to operate; the mutation effect is better than that of the traditional physical and chemical mutagenesis method, and the femtosecond laser mutagenesis method has great popularization value in breeding of microorganism pharmaceutical strains; by using the femtosecond laser irradiation to perform the mutagenesis, the high-yield ascomycin mutation strain can be bred. The positive mutation rate of the mutation strain is 5-30%, and fermenting unit is improved by 10-60% in comparison with that of an original strain.

The invention discloses L-arginine producing strain corynebacterium glutamicum ZD2009, CCTCC NO:M209260 and a preparation method and application. The preparation method comprises the following steps of: A, performing ultraviolet mutagenesis, namely culturing the corynebacterium glutamicum, centrifuging, removing supernatant, washing, and scattering the strain by using glass beads to obtain cell suspension; B, performing 1-methyl-3-nitro-1-nitrosoguanidine mutagenesis, namely culturing the corynebacterium glutamicum, centrifuging, removing the supernatant, washing, scattering the strain by using the glass beads, washing with phosphate buffer after washing, adding 1-methyl-3-nitro-1-nitrosoguanidine for mutagenesis, washing with the phosphate buffer to remove the 1-methyl-3-nitro-1-nitrosoguanidine and stopping the mutagenesis; C, determining shake flask fermentation conditions; D, determining a fermentation medium and inoculation amount; E, determining pH value; and F, determining liquid loading amount. The acid producing amount of the L-arginine producing strain corynebacterium glutamicum reaches 44g/L; and the strain produces the acid stably, has high genetic stability, reduces production cost and improves efficiency.

The invention discloses a sodium azide mutagenizing method for juvenile citrus internodal stem segments, comprising: I, taking citrus young plantlets more than 1 mm in stem thickness and 5-10 cm in plantlet height, cutting to obtain internodal stem segments, soaking the internodal stem segments in a mutagenizing liquid, mutagenizing in darkness for 1-3 h, wherein the mutagenizing liquid includes sodium azide having a concentration of 0.5-2 mmol/L; II, subjecting the mutagenized internodal stem segments to tissue culture until sectional wounds of the internodal stem segments grow regenerated buds; III, using an SRAP (sequence-related amplified polymorphism) molecular markup method to detect the regenerated buds that vary, and subjecting the varied regenerated buds to rooting culture to obtain complete citrus variant plants. It is clarified that sodium azide-mutagenized juvenile citrus internodal stem segments may produce stable variant plants. The method of the invention has mutagenizing efficiency of greater than 10% and has significant mutagenizing effect and good operating convenience.

The invention discloses a method for widening tetraploid wheat genetic variation. The method comprises the following steps that parent tetraploid wheat AABB is utilized to hybridize with diploid aegilops tauschii DD, in-vitro culture is carried out on a hybrid young embryo ABD to obtain an ABD plant seedling, then chromosome doubling treatment is carried out to obtain low-generation artificially synthesized hexaploid wheat AABBDD, the low-generation artificially synthesized hexaploid wheat AABBDD is backcrossed with the same parent tetraploid wheat AABB to obtain a pentaploid wheat material AABBD, the pentaploid wheat material is used for selfing, chromosome behaviors such as chromosome exchange, translocation, inversion, deletion and insertion are generated through chromosome recombination in the selfing process, rich variation types are generated in genetic offspring, and a new tetraploid wheat material composed of different chromosomes is formed. According to the method, the chromosome of the tetraploid wheat can be induced to generate new structural variation in a relatively short time, and the method is high in beneficial mutation efficiency, rich in mutation type, environment-friendly, safe and low in cost.

The invention discloses a method of utilizing sodium azide to induce bud mutation of poinsettia. The method includes treatment steps: using a scalpel to pinch poinsettia, reserving an internode on anaxillary bud of 2-5cm during pinching, using a liquid transfer gun to extract 100-500ml of NaN3 solution, injecting into the internode, and wrapping a notch; putting treated poinsettia in a greenhousefor culture, watering, fertilizing, and waiting for a new bud to grow out after 1 month, wherein concentration of the NaN3 solution is 0.02-0.08%. The method specifies conditions like concentration and treatment methods for effectively inducing bud mutation of poinsettia, is simple and convenient in research and development and can be effectively applied in bud mutation breeding of poinsettia, and the problem that poinsettia is small in natural mutation rate and the problem that resource innovation of poinsettia cannot be performed actively on a large-scale are solved.

The invention discloses a method for establishing a mutant strain by utilizing a plasma induced lucid ganoderma protoplast. The method comprises the following steps that 1, a lucid ganoderma protoplast is established, wherein a liquid lucid ganoderma culture mycelium is prepared, a mycelium homogenate is prepared, a cell wall resolvase solution is prepared and cell walls are dissolved, the protoplast is separated and collected, and the protoplast concentration is corrected and saved; 2, protoplast mutation is induced by low-temperature plasma, wherein preparation is performed before protoplast mutation, a plasma mutagenesis device is ventilated for balance, a reaction system is electrified for protoplast mutation, a flat protoplast plate is evenly coated and standing regeneration and culture are performed, a mutant strain is selected, the colonial morphology and growing rate are observed and recorded, and hypha morphology is observed under a light microscope, active substances and stability of the mutant strain are detected, and the strain is saved. The method has the advantages of stably and efficiently utilizing plasma to induce the lucid ganoderma protoplast so as to establish the mutant strain.

The present invention relates to a method for conducting high-throughput and directed mutagenesis for sugarcane resistance to glyphosate by plasma. The method is as follows: sugarcane embryonic calli are irradiated by a plasma instrument under a sterile condition for mutagenesis, wherein the mutagenesis power is 140˜200 W, the discharging distance is 35˜45 mm, the mutagenesis time is 110˜140 s and the protective gas is nitrogen; buffering culture, moderate/high concentration of glyphosate stress screening, differentiation into seedlings, glyphosate stress screening of bottle seedlings and stress screening via spraying glyphosate on the leave surfaces of potted plants are conducted for the treated calli. The present invention has the advantages of safe operation, simplicity, practicability, high handling capacity, low contamination, and due to implementation of directed stress screening, high screening efficiency, decreased subsequent screening workload and visual identification of resistant mutant strains.

The invention discloses a treatment method capable of increasing the rice healing aberration generation rate by irradiation mutagenesis. The treatment method includes the steps of (1), exposing rice seeds to high-dose cobalt-60 gamma-ray to radiation; (2), subjecting the rice seeds obtained after the step (1) to microwave irradiation; (3), exposing the rice seeds obtained after the step (2) to low-dose cobalt-60 gamma-ray to radiation; (4), subjecting the rice seeds obtained after the step (3) to microwave irradiation; (5), cultivating the rice seeds obtained after the step (4) and performing excellent character selection, superior single selection and excellent resource and variety identification. The treatment method treats the rice seeds by combining cobalt-60 gamma-ray irradiation with microwave irradiation, so that the restriction that variation types are generated through single mutagenesis is overcome, and mutagenesis efficiency is improved.

The invention discloses a chemical mutagenesis processing device for plant material, wherein the chemical mutagenesis processing device for plant material comprises a frame (1), at least one mutagenesis processing chamber (5) and at least one continuous dosing chamber (4), wherein the at least one mutagenesis processing chamber (5) is used for placing plant material for mutagenesis, arranged on the frame (1) and provided with a medicine liquid inlet (15) and a discharge hole (19); the inside of the mutagenesis processing chamber (5) is provided with a temperature control heating device (16) which is used for heating the medicine liquid and detecting the temperature; at least one continuous dosing chamber (4) is used for holding the medicine liquid, arranged on the frame (1) to be corresponding to the mutagenesis processing chamber (5) and provided with the medicine liquid outlet (12); the height of the medicine liquid outlet (12) is greater than the height of the corresponding medicine liquid inlet (15); the medicine liquid outlet (12) is connected to the corresponding medicine liquid inlet (15) through the liquid inlet pipe (32); the liquid inlet pipe (32) is provided with a liquid inlet valve (31). Through the device, the best reaction temperature can be kept for the whole mutagenesis process; the activity of the mutagenic agent is guaranteed; the device is high in mutagenesis efficiency and good in effect.