215results about How to "High genetic stability" patented technology

The teachings herein are generally directed to a method of enhancing the genetic stability of parvovirus vectors. The stability of conventional ss or dsAAV vector constructs can be enhanced, for example, to obtain a concurrent increase in vector titer and purity, as well as an improvement in vector safety, due at least in part to the elimination of stuffer DNA from the AAV vector. The method is broadly applicable to all gene transfer / therapy applications, such as those requiring delivery of foreign DNA containing recombinant gene expression cassettes. Such foreign DNA can range, for example, from about 0.2 up to about 5.2 kb in length. The enhanced vector constructs are highly flexible, user-friendly, and can be easily modified (via routine DNA cloning) and utilized (via standard AAV vector technology) by anyone skilled in the art.

The present invention relates to the quick breeding method of high quality seedling of Phalaenopsis, known as 'queen orchid' and the culture medium therewith. The present invention uses the flower stem section of Phalaenopsis as explant and induces flower stem seedling with unique culture medium and performs proliferation with fascicular bud stem tip or stem section to produce high quality seedling of Phalaenopsis. The method is simple, practical, feasible and high in application value.

The invention provides a high-temperature resistant saccharomyces cerevisiae strain and a breeding method of the high-temperature resistant saccharomyces cerevisiae strain. The saccharomyces cerevisiae (Saccharomyces cerevisiae) SY-5-11L has a preservation number of CGMCC No.7377. The strain is characterized in that the ethanol yield is 13.9% (v / v) at a condition of fermenting at high temperature of 38 DEG C on the premise that other fermenting performances are not influenced, the yield is improved by 17.8% as compared with that of a parent strain. The ethanol output at the condition of fermenting at high temperature of 40 DEG C is 12.2% (v / v), and is improved by 34.1% as compared with that of the parent strain. The breeding method comprises the following steps of: performing artificial ultraviolet mutagenesis on an initial strain of the saccharomyces cerevisiae; screening out 23 forward mutant strains as a genome rearrangement library, wherein the ethanol output of the forward mutant strains are obviously raised on the condition of fermenting at a high temperature; and performing the genome rearrangement at three rounds, thus gaining the mutant strains with the maximum ethanol output under the high-temperature fermenting condition. The finally bred saccharomyces cerevisiae strain can be subjected to alcoholic fermentation at the high-temperature fermenting condition, brings no special requirements to fermenting equipment and technological conditions, and can be put into service with the equipment and conditions of general plants, thus having a wide application prospect.

The invention discloses a method for cultivating a subcultured bud of an upright crown tissue culture seedling of fir wood. The method comprises the following steps: an excellent clonal annual burgeon of the fir wood is used as an explant, a breeding bud is obtained through disinfection, sterilization and tissue culture, the breeding bud is innoculated in a proliferation culture medium comprising 1 / 2MS, 1.0mg / L of 6-BA and 0.5mg / L of IBA for inducing the cluster buds to sprout, the subcultured bud which is germinated at the base of the breeding bud and is healthy in growth is selected and is cut in a common rooting culture medium, seedlings are exercised and transplanted, and when the height of the seedlings of the fir wood is 15-30 cm, the seedlings are taken out of a garden for forestation. When the method is used, the proliferation rate of the subcultured bud of the fir wood is as high as 4-6, the breeding speed is high, the seedling culturing number is large, the tissue culture subcultured bud with high genetic stability, 100% of the upright crown rate of the tissue culture seedling and more than 96% of the rooting rate can be in batch production in a short period, and the requirements of the construction and the development of a fir wood reserving base of China for good seedlings can be met, so that the method has better economic benefits, social benefits and ecological benefits.

The invention discloses a method for modifying hybrid matching strains of Sansui duck. The method includes firstly, selecting breeding female and male ducks; secondly, feeding the breeding female and male ducks; thirdly, establishing and managing a feeding area; fourthly, hybridizing; and fifthly, feeding in the laying stage. By optimized purification and hybridization, genetic stability of fine characters of the Sansui duck such as meat quality and the like is improved, and growth speed and feed reward of the Sansui duck are increased. The strains are established and are propagated, and accordingly the related contradiction between low growth speed and meat quality is overcome. Hybridization experiments are performed, hybrid vigor of the Sansui duck is taken advantage, the strains are selected and bred selectively, and breeding value of the Sansui duck is increased. By strain selection and selective breeding, feeding management condition improvement and the like, fertilizing rate andhatching rate are increased, breeding egg quality is improved while reproduction rate is increased, and disease resistance of Sansui duck is improved. The method is applicable to strain modification for Sansui duck.

An in-vitro culture method for catalpa bungei comprises 1) inducing callus, concretely, putting catalpa bungei on a callus induction medium for inducing callus, wherein the callus induction medium is obtained by adding 6-benzyladenine (6-BA) and 2,4-dichlorophenoxyacetic acid (2,4-D) on the basis of 1 / 2 MS basal medium; 2) propagating callus, concretely putting callus on a propagation medium for propagation, wherein the propagation medium is obtained by adding 6-benzyladenine (6-BA) and alpha-naphthalene acetic acid (NAA) on the basis of 1 / 2 MS basal medium; 3) inducing embryonic callus and differentiating somatic embryo, concretely putting propagated callus on an induction differentiation medium, wherein the induction differentiation medium is obtained by adding 6-benzyladenine (6-BA) and alpha-naphthalene acetic acid (NAA) on the basis of 1 / 2 MS basal medium; and 4) regenerating a plant, concretely putting somatic embryo obtained through differentiation on a regeneration medium for inducing somatic embryo to germinate, so as to obtain a catalpa bungei regeneration plant. The method aims at expanding catalpa bungei propagation coefficient and providing conditions for germplasm preservation and genetic transformation.

The present provides attenuated influenza viruses comprising a modified viral genome containing a plurality of nucleotide substitutions. The nucleotide substitutions result in the rearrangement of preexisting codons of one or more protein encoding sequences and changes in codon pair bias. Substitutions of non-synonymous and synonymous codons may also be included. The attenuated influenza viruses enable production of improved vaccines and are used to elicit protective immune responses.

The invention discloses a watermelon tissue culture seedling grafting method, comprising the following steps: stock preparation, scion preparation, grafting, grafted seedling culturing, grafted seedling transpiration and the like. Stock seeds are sowed in a nutrition disc after pregermination, and can be grafted after two leaves and one bud grow; 2-3cm-high watermelon tissue culture seedlings are domesticated and subjected to scion ingraftment, and grafted through a top grafting method; the grafted seedlings are subjected to timely heat preservation, humidity preservation, shading culturing, and shoots of stock are timely removed; and the grafted seedlings with two leaves and one bud can be transplanted into the land for growing field crops and subjected to field management as same as common grafted seedlings. According to the invention, rooting is avoided in the tissue culture seeding culturing, the problem of difficulty in rooting or instability can be overcome by directly obtaining the watermelon grafted seedlings; the method can be carried out all the year round with artificially controlling conditions, is short in period, high in rate of survival, simple and feasible and convenient to operate, the production cost of the watermelon grafted seedlings is reduced, and the problems of imperfect regeneration plant rooting effect and low transportation survival rate during watermelon tissue culturing are solved.

The invention discloses streptomyces albidoflavus Actin-1. The streptomyces albidoflavus Actin-1 can grow and propagate with apple tree rot pathogenic bacterium mycelium as nutrition, long-term colonization of biocontrol bacteria on apple tree rot scabs is promoted, a long-term biological prevention and treatment function is achieved, meanwhile, the streptomyces albidoflavus Actin-1 is induced to generate multiple ectoenzyme cell wall hydrolytic enzymes, and pathogenic bacterium cells disintegrate in combination with the enzyme dissolving function; high antibacterial active matter can be generated, the bacteriostasis rate on the apple rot pathogenic bacteria is 89.82%, a good antibacterial effect is achieved on botryosphaeria berengeriana and other pathogenic bacteria, the bacteriostasis rate ranges from 76.08% to 87.10%, and broad spectrum bacteriostasis performance is achieved. The streptomyces albidoflavus Actin-1 is adopted as main biocontrol bacteria for preventing and treating the apple tree rot and other fruit and vegetable pathogenic bacteria, and the advantages of being good in prevention and treatment effect (100%), high in efficiency, low in recurrence rate (0), high in environment adaption capacity, high in stability, not likely to generate resistance to drugs and the like are achieved. Important significance is achieved on improving the prevention and treatment effect on the apple tree rot and other fruit and vegetable pathogenic bacteria, preventing pathogenic bacterium relapse and protecting the environment.

The disclosure provides for an isolated recombinant influenza virus having at least one of: a PA gene segment encoding PA with a residue at position 443 that is not arginine, a PB1 gene segment encoding PB1 with a residue at position 737 that is not lysine, a PB2 gene segment encoding PB2 with a residue at position 25 that is not valine or a residue at position 712 that is not glutamic acid, a NS gene segment encoding a NS1 with a residue at position 167 that is not proline, a HA gene segment encoding a HA with a residue at position 380 that is not threonine, or any combination thereof, and methods of making and using the virus.

The invention discloses uracil auxotroph Hansenula yeast gene engineering host strain Hansenula yeast YH-11 CGMCC NO.2976 with stable heredity, and simultaneously provides a construction method for the Hansenula yeast. The construction method comprises the following steps: 1) constructing recombinant plasmid p18HURA containing orotidine-5-phosphate decarboxylase gene (HURA3) of the Hansenula yeast; and 2) constructing recombinant plasmid pHURK for the HURA3 with disrupted gene; and converting the plasmid pHURK of step 2) into the Hansenula yeast by using a yeast whole cell conversion method, and obtaining the uracil auxotroph strain through screening. The invention further discloses application of the constructed uracil auxotroph Hansenula yeast gene engineering host strain Hansenula yeast in producing foreign protein.

The invention discloses an antibiological inoculant for controlling apple tree canker, and application of the antibiological inoculant. The antibiological inoculant can grow and propagate directly by using pathogenic mycelium as nutrition, and can induce the self to produce multiple extracellular enzyme capable of degrading cell walls of pathogenic bacteria; a streptomyces albidoflavus Actin-1 strain, colonized at disease spots of the apple tree canker for a long time, is activated and subjected to spore production, so that spore suspension is prepared; after that, a fermented seed solution is prepared by continuously carrying out liquid fermentation; finally, the fermented seed solution is inoculated into a solid fermentation medium, and is then fermented, dried in the air, crushed and screened so as to be prepared into spore raw powder; the spore raw powder is then scientifically screened and compounded by using auxiliary agents such as an ultraviolet protective agent, a dispersing agent and a carrier. The antibiological inoculant provided by the invention has the multiple advantages of being good in control effect, high in efficiency, low in recurrence rate and high in environmental adaptability and stability, not easy in producing drug-resistance, and the like, thus being a first choice for biological control; the antibiological inoculant has a great significance for improving the preventing and treating effect of fruit and vegetable pathogenic bacteria such as the apple tree canker, preventing pathogen recurrence and protecting environment.

The teachings herein are generally directed to a method of enhancing the genetic stability of parvovirus vectors. The stability of conventional ss or dsAAV vector constructs can be enhanced, for example, to obtain a concurrent increase in vector titer and purity, as well as an improvement in vector safety, due at least in part to the elimination of stuffer DNA from the AAV vector. The method is broadly applicable to all gene transfer / therapy applications, such as those requiring delivery of foreign DNA containing recombinant gene expression cassettes. Such foreign DNA can range, for example, from about 0.2 up to about 5.2 kb in length. The enhanced vector constructs are highly flexible, user-friendly, and can be easily modified (via routine DNA cloning) and utilized (via standard AAV vector technology) by anyone skilled in the art.

In the invention, apical bud of zephyr lily bulb is selected for fast inducing to produce a large number adventitious buds, regeneration plant is obtained by generation and rooting of the adventitious buds, survival percentage of the regeneration plant reaches 100%; in addition, the method of the invention has the advantages of fast propagation speed, no confinement to seasons, acquisition of apical bud isolated organ at any time for tissue culture, small mutation of the regeneration plant, high genetic stability, healthy regeneration plant and shortened seedling period.