344 results about "Mutagenesis" patented technology

The present invention belongs to the technical field of biological prevention and treatment for viral diseases. Disclosed in the present invention are a tomato disease-resistant gene mutant, and the use thereof in the prevention and treatment of ToBRFV. It is found in the present invention that mutating the nucleotide at position 1927 of the coding region sequence of tomato Tm-22 gene from G to A, or mutating the amino acid at position 643 of the LRR domain of a protein that is encoded by tomato Tm-22 gene from glycine to arginine can remarkably reduce the accumulation level of ToBRFV capsid protein (CP). The gene (named Tm-22-Mut5) can serve as a novel ToBRFV resistant gene, and also retains the resistance to TMV, ToMV and ToMMV. The Tm-22-Mut5 and a pre-screened Tm-22-Mut3-1 mutant (tyrosine at position 767 of the LRR domain thereof is mutated to phenylalanine) undergo combinatorial mutagenesis to obtain a mutant Tm-22-Mut6. Analysis shows that the Tm-22-Mut6 can remarkably reduce the accumulation level of the ToBRFV capsid protein. Compared with the pFGCTm-22-Mut3-1 mutant obtained by screening in the previous research and the newly obtained mutant Tm-22-Mut5, the Tm-22-Mut6 has further improved resistance to ToBRFV.

The present disclosure relates to Taq DNA Polymerase mutants comprising at least three mutations which are capable of high levels of DNA amplification in the presence of several PCR inhibitors and compositions comprising the same. Also disclosed are methods of performing mutagenesis on wild-type Taq DNA polymerase to obtain the disclosed Taq DNA polymerase mutants, DNA amplification using the same, and cDNA amplification using the same.

The invention belongs to the technical field of biology, and particularly discloses a tryptophan production strain and application thereof. The L-tryptophan high-yield strain T29 is developed and obtained through methods of combining gene modification with mutagenesis screening and the like. The strain T29 is fermented in a 5L tank, the highest yield of L-tryptophan can reach 60.7 g / L, and the conversion rate reaches 18.6%. Therefore, the strain provided by the invention has important industrial application value for industrial production of L-tryptophan and development of an L-tryptophan production strain with higher fermentation performance.

The invention discloses a method for screening high-yield recombinant human lactoferrin through nucleic acid aptamer-assisted mutagenesis of a trichoderma reesei strain and application, and belongs to the technical field of microorganisms. The nucleic acid aptamer Lac-6a-FAM-BHQ1 capable of changing the fluorescence intensity according to the content of lactoferrin is constructed on the basis of the aptamer Lac-6a, and the nucleic acid aptamer can be used for rapidly selecting a mutant strain for producing high-titer recombinant human lactoferrin. The ARTP mutagenesis technology is combined with a nucleic acid aptamer auxiliary screening system, the mutant strain with the improved recombinant human lactoferrin yield is rapidly obtained from a large number of mutant strains, and the yield reaches 274.57 mg / L and is improved by 24.8% compared with that of an original strain. After the genes 111681 and 62716 are over-expressed in T. reesei, compared with a control strain, the yields of the recombinant human lactoferrin of the recombinant strain are respectively increased by 6.9% and 22.1%.

The invention provides Saccharomyces cerevisiae for producing squalene as well as a screening method and application of the Saccharomyces cerevisiae. The method comprises the following steps: culturing a Saccharomyces cerevisiae engineering strain ySC782 for synthesizing squalene to obtain a to-be-mutagenized bacterial solution, carrying out ARTP mutagenesis on the to-be-mutagenized bacterial solution, adding the to-be-mutagenized bacterial solution into a YPD liquid culture medium, culturing to obtain a resuscitation bacterial solution, adding the resuscitation bacterial solution into a sucrose solution with gradient concentration distribution, screening, and repeating the ARTP mutagenesis-sucrose solution screening step to obtain the squalene mutant strain. And finally, the saccharomyces cerevisiae strain ySC782-M5 is obtained through screening, and the saccharomyces cerevisiae strain ySC782-M5 is obtained through screening. The yield of squalene produced by the saccharomyces cerevisiae ySC782-M5 reaches 49.83 g / L, so that a solution is provided for breaking through the yield bottleneck of squalene synthesized by yeast.

Disclosed herein are methods and systems for aligning sequence reads based on reduced sequence representations. The methods and systems may include receiving sequence reads generated from nucleic acids; encoding sequence reads with a reduced sequence representation, thereby generating transformed sequence reads; generating seeds from the transformed sequence reads; and matching the seeds, thereby aligning the transformed sequence reads. The methods and systems may improve alignment efficiency and accuracy, for example when used with sequence reads which include mutations or sequencing errors, such as in sequencing aided by mutagenesis (SAM) or long-read sequencing applications.

The invention belongs to the field of microbial breeding and fermentation engineering, and particularly relates to a saccharomyces cerevisiae mutagenesis strain with high yield of S-adenosyl-L-methionine as well as a mutagenesis method and application of the saccharomyces cerevisiae mutagenesis strain. Saccharomyces cerevisiae is induced to generate genetic diversity through multiple rounds of ultraviolet mutagenesis, and high-throughput screening is performed in combination with strain color phenotypic difference; and the mutant strain HY2402-Z18 with high yield of S-adenosine-L-methionine and genetic stability is obtained. The SAM yield of the mutagenic strain is increased by 40.1% compared with that of an original strain, the SAM yield reaches 13.44 g / L when the mutagenic strain is fermented for 60 h in a 5 L fermentation tank system, the unit yield reaches 0.156 g / L / OD, and the methionine conversion rate is 75%. After thalli are collected through centrifugation of fermentation liquor, an S-adenosine-L-methionine product with the purity of 98%-100% can be obtained through purification of ion exchange resin, no by-products are accumulated, the yield, the substrate conversion rate and the production efficiency of the S-adenosine-L-methionine can be remarkably improved when the mutagenesis strain is used for fermentation production, and the production cost is reduced. The production cost is effectively reduced, the product purity and quality are improved, and the method is suitable for industrial large-scale production of SAM.

The invention discloses a preparation method of ganoderma lucidum mutant strain active polysaccharide and application of the ganoderma lucidum mutant strain active polysaccharide in oxidation resistance, and relates to the technical field of biology. The ganoderma lucidum mutant strain active polysaccharide is prepared by taking mycelium of a ganoderma lucidum mutant strain CGMCC No.23283 as a raw material and adopting a water extraction and alcohol precipitation method. The invention develops a novel ganoderma lucidum active polysaccharide, and a ganoderma lucidum strain adopted by the ganoderma lucidum active polysaccharide is cultured by a space mutation technology. Compared with common ganoderma lucidum strain polysaccharide, the polysaccharide provided by the invention is more prominent in antioxidant activity, and is more excellent in key indexes such as total antioxidant capacity and free radical scavenging. The invention provides a new biological material resource for the preparation of antioxidant products.

This invention discloses a method for directed evolution of antibiotic-resistant Escherichia coli strains based on cytidine deaminase, belonging to the field of microbial directed evolution and genetic engineering technology. This method uses E. coli as the host, introducing a recombinant plasmid expressing an optimized double-stranded cytidine deaminase mutant. Utilizing the low toxicity and high mutagenicity of this mutant, continuous passage evolution is carried out under gradient concentrations of aminoglycoside antibiotics (kanamycin and streptomycin). Combined with whole-genome sequencing, molecular docking, and reverse genetics verification, the A145T missense mutation in the wcaE gene is identified as the core functional site. This invention overcomes the shortcomings of traditional spontaneous and chemical mutagenesis, which suffer from low efficiency and significant strain damage. The mutation type is controllable, the evolutionary cycle is short, and the obtained engineered strains can tolerate up to 300 mg / L kanamycin while exhibiting streptomycin cross-resistance, and the genetic stability of the tolerance trait is strong. This method is simple, highly reproducible, and suitable for industrial breeding of stress-resistant E. coli, and can be widely applied in antibiotic fermentation, industrial microbial culture, and other scenarios.

The disclosure provides Moloney murine leukemia virus (MMLV) reverse transcriptase (RTase) mutants. The disclosure as provides suitable amino acid positions in MMLV RTase for mutagenesis and methods and kits for using MMLV RTase mutants to synthesize cDNA from RNA templates.

The disclosure relates to commercially elite hard red winter wheat varieties having increased dough strength. The wheat variety designated OK15MASBx7 ARS 8-20, the plants and seeds and plant parts of wheat variety OK15MASBx7 ARS 8-20, methods for producing a wheat plant produced by crossing the variety OK15MASBx7 ARS 8-20 with another wheat plant, and hybrid wheat seeds and plants produced by crossing the variety OK15MASBx7 ARS 8-20 with another wheat line or plant, and the creation of variants by mutagenesis or transformation of variety OK15MASBx7 ARS 8-20 are also provided. Methods for producing other wheat varieties or breeding lines derived from wheat variety OK15MASBx7 ARS 8-20 and wheat varieties or breeding lines produced by those methods are also provided. Further provided are commodity plant products from wheat varieties having increased dough strength.

This disclosure provides improvised reagents and methods for inserting a transgene into the genome of a living host cell. Sleeping beauty (SB) transposase is used in protein form rather than as a vector. This has been made possible by using rational mutagenesis in a particular region of the SB crystal structure to develop variant SB transposase protein that is more soluble. The changes increase solubility while maintaining transposase activity, thereby adapting the variant transposase for the purpose of promoting recombinant integration of a transgene into a target cell when used in protein form rather than as a polynucleotide vector. The modified transposase is highly soluble in electroporation buffer and thermostable during storage. When introduced into a host cell, it promotes integration of a transgene into the genome of the cell in a dose-dependent manner. It is degraded within 48 hours, thereby rapidly clearing transposase activity from the host cell.

A wheat variety designated 6PBDH22B, the plants and seeds of wheat variety 6PBDH22B, methods for producing a wheat plant produced by crossing the variety 6PBDH22B with another wheat plant, and hybrid wheat seeds and plants produced by crossing the variety 6PBDH22B with another wheat line or plant, and the creation of variants by backcrossing, mutagenesis or transformation of variety 6PBDH22B are disclosed. Methods for producing other wheat varieties or breeding lines derived from wheat variety 6PBDH22B and to wheat varieties or breeding lines produced by those methods are also provided.

The invention belongs to the technical field of solid waste recycling, and discloses efficient carbon sequestration pseudomonas stutzeri from an oil-containing solid waste residue source and application of the efficient carbon sequestration pseudomonas stutzeri, and the efficient carbon sequestration pseudomonas stutzeri is pseudomonas stutzeri A58-5 with the preservation number of CCTCC NO: M 20241582. The Pseudomonas stutzeri is obtained by taking Pseudomonas stutzeri A58 separated from oil-containing solid waste residues of an oil field as an original strain and carrying out ARTP mutagenesis and screening, has the excellent characteristics of reducing pollution and sequestering carbon and is relatively strong in stress resistance; the method has wide application prospects in the fields of deep recycling (soil conversion) of oil-containing solid waste residues, improvement of the carbon sequestration capacity of the petroleum-contaminated soil, remediation of the petroleum-contaminated soil and the like, and is of great significance in pollution reduction and sequestration increase in the petroleum and petrochemical industry under the background of supporting double carbon.

The invention belongs to the technical field of biology, and particularly relates to Meyerozyma caribba XX2120, and the preservation number of the Meyerozyma caribba XX2120 is GDMCC No: 67777. The invention further relates to a preparation method of the Meyerozyma caribba XX2120. The strain is obtained by taking saccharomycetes X2120 as a starting strain, carrying out ARTP mutagenesis treatment and screening, has relatively strong acid resistance, relatively high salt stress resistance and certain alcohol resistance and aldehyde resistance, can effectively utilize monosaccharide, disaccharide and trisaccharide, has a wide utilization range on carbohydrate and has a relatively good utilization rate on inorganic nitrogen. Moreover, the strain can be used for producing mycoprotein through liquid fermentation by taking Luzhou-flavor distillers' grains as a raw material, and also can be used for performing solid fermentation on the Luzhou-flavor distillers' grains, so that the true protein content of the distillers' grains is increased, the nutritional value of the distillers' grains is improved, and the recycling of distillers' grain resources is effectively promoted.

The present disclosure provides Moloney murine leukemia virus (MMLV) reverse transcriptase (RTase) variants. The present disclosure further provides amino acid positions for mutagenesis of MMLV RTase as well as nucleic acids, kits, compositions, fusion proteins, and methods including MMLV RTase variants.

The invention relates to a high-yield protein glutaminase Chryseobacterium prion strain and a preparation method thereof. The strain is obtained by carrying out ARTP and NTG compound mutagenesis treatment on an original strain of Chryseobacterium prion and carrying out high-throughput screening on the strain subjected to the compound mutagenesis treatment. The strain is preserved in the China Center for Type Culture Collection, and the preservation number is CCTCC M 20251792. The invention also relates to a method for preparing protein glutaminase by using the strain of the invention. The enzyme activity of the protein glutaminase of the strain is 6 times that of an original strain, and the production efficiency of the protein glutaminase can be remarkably improved.

The invention discloses a saline-alkaline tolerant rice mutation breeding identification and evaluation system based on heavy ion beam radiation, and relates to the technical field of intelligent agriculture, and the system comprises a phenotype dynamic sensing module which is used for carrying out real-time monitoring and abnormity identification on the growth state of rice under saline-alkaline stress so as to identify and output an early abnormal phenotype signal, and determining the abnormal phenotype of plant growth. According to the method, multi-dimensional phenotype data of rice under different saline-alkaline gradients are collected in real time through a multi-source sensor network, the problem of inconsistent growth periods caused by environmental differences is solved by utilizing a dynamic time warping algorithm, a basic identification data set with aligned time sequences is constructed, abnormal phenotype identification is further performed by adopting a local abnormal factor algorithm, and the identification accuracy is improved. Early deterioration early warning of the plant growth state under saline-alkali stress is achieved, the problems of high misjudgment rate and low efficiency in traditional field screening are effectively solved, and reliable data support is provided for early identification of saline-alkali tolerant rice varieties.

The invention provides a GMRM (Genome-based Mutant RNA Mapping) method taking a genome as a reference, in particular, the invention provides a method for cloning candidate functional genes of wheat stripe rust resistant plants and an analysis process, and the GMRM method disclosed by the invention can be used for simultaneously cloning two genes with complementary disease-resistant functions, namely Yr6NLR1 and Yr6NLR2. In an example of Yr6, the two disease-resistant genes are closely linked genetically, but the cloning process of the genes does not involve any genetic recombination. Therefore, theoretically, the method provided by the invention can be used for simultaneously cloning a plurality of functional complementary genes (namely genes participating in the same pathway) on the premise that the target gene can generate effective mutation through EMS mutagenesis.

The present application relates to the technical field of plant breeding, and in particular to a mutation breeding method for Phyllostachys edulis based on ARTP. The mutation breeding method comprises: using atmospheric room temperature plasma to treat the seeds of Phyllostachys edulis, and the parameters include: radio frequency power of 200-400 W, radiation distance of 2-3 mm, and treatment time of 8-55 minutes. The present application studies a mutation breeding method suitable for Phyllostachys edulis, and through a specific degree of ARTP mutation of the seeds of Phyllostachys edulis, the number of tillers of the seedlings of Phyllostachys edulis can be increased and the yellowing rate of the seedling of Phyllostachys edulis can be reduced under the condition of ensuring a certain seedling rate. The mutation breeding method provided by the present application can be used for breeding Phyllostachys edulis varieties with excellent traits, and has important value in the field of Phyllostachys edulis breeding.

The invention relates to the technical field of microbial fermentation and food processing, and particularly discloses Weissella fusiformis JMF-006 as well as a mutagenesis method and application thereof. The invention provides a Weissella fusiformis JMF-006 with the exopolysaccharide yield of 20-25g / L. The Weissella fusiformis JMF-006 is obtained by breeding through a mutation breeding method of a high-yield EPS strain, and the mutation breeding method can also be used for culturing other high-yield EPS strains. The invention provides a strain composition, the strain composition comprises Weissella fusiformis JMF-006 or a high-yield EPS strain, other lactic acid bacteria strains (such as lactobacillus plantarum JMF-001 and lactobacillus casei JMF-002) can be further compounded, and the obtained strain composition has more excellent fermentation performance. When the Weissella fusiformis JMF-006, the high-yield EPS strain and the strain composition provided by the invention are applied to the fermentation process of food-derived drinks, a fermented product with stable properties and better flavor can be obtained, and the technical problems that the yield of extracellular polymeric substances is low, the fermentation performance is poor and the application range is narrow in an existing lactic acid bacteria starter are solved.

This invention relates to a method for rapidly screening filamentous fungi that produce high levels of triglycerides and polyunsaturated fatty acids, belonging to the field of microbial technology. The method employs a two-stage screening strategy of "resistance primary screening – fluorescence secondary screening." In the primary screening stage, strains with strong lipid synthesis capabilities are initially screened by adding a combination of phytocyanin and quizalofop-p-ethyl inhibitors to the culture medium. In the secondary screening stage, cellophane culture technology and Nile red fluorescence staining are combined to quantitatively assess the triglyceride content of the colonies, achieving rapid and non-destructive screening. This method is simple to operate, highly efficient, and shows a significant positive correlation between fluorescence intensity and triglyceride content. It is suitable for mutagenesis breeding and industrial strain selection of oil-producing filamentous fungi such as *Morchella alpineensis*.

The present disclosure provides base editor fusion proteins, complexes, and systems capable of installation of multiple edits across large genomic windows (e.g., between 4bps and 500 bps) and which may be useful, for example, for mutating one or more nucleotides in a target nucleic acid. The disclosure describes gene editing systems comprising a first fusion protein comprising a C-terminal portion of a split deaminase and a first epitope binding domain, a second fusion protein comprising a N-terminal portion of a split deaminase and a second epitope binding domain, and a third fusion protein comprising a DNA binding protein domain and one or more epitope domains to which the first and second fusion proteins may bind (along the one or more epitope domains), thereby forming an active deaminase domain. The base editor fusion proteins, complexes and systems can be used in certain embodiments in methods of performing mutational screens in a gene of interest. Other aspects of the disclosure relate to methods, for example, methods of mutating one or more nucleotides in a target nucleic acid and methods of performing mutational screens. The disclosure also provides compositions, polynucleotides, vectors, pharmaceutical compositions, cells, kits, and systems comprising the base editor fusion proteins and complexes contemplated herein.

The invention relates to the field of mutant strain screening models, in particular to a uranium pollution remediation forward mutant strain screening model and a construction method thereof.The construction method comprises the following steps that mutant strains are irradiated, and mutant strains are obtained; determining functional index data of the mutant strain, and respectively calculating standard scores of all functional indexes through a Z-score formula; performing principal component analysis and bidirectional clustering analysis by using standard scores to obtain dominant indexes of the mutant strains; obtaining the subjective weight WAHP of the function index of each scheme layer through an analytic hierarchy process; calculating objective weight WEWM of each function index through an entropy weight method; calculating a combined weight W by adopting a linear weighted fusion method; and calculating a comprehensive score of each model to complete model construction. According to the invention, the regulation and control rule of the electron beam irradiation dose on the multifunctional traits of the three strains is systematically explored, a comprehensive screening model suitable for multiple scenes is constructed in combination with an AHP-entropy weight method, and a theoretical basis, high-quality germplasm resources and a scientific and efficient screening method are provided for directional breeding of uranium pollution remediation microorganisms.

This invention belongs to the field of microbial metabolic engineering and synthetic biology, specifically relating to a strain for high-yield... R,R -2,3-Butanediol ( R,R Salt-tolerant Jeju Bacillus DT01 IM3 DLB6 (-2,3-BDO), production strain constructed from this strain and its application in fermentation production. R,R Applications of -2,3-BDO. This invention screens a high-yielding strain through heavy ion beam irradiation mutagenesis. R,R Jeju Bacillus DT01 IM3 DL B6 with -2,3-BDO, preservation number CGMCC No. 37311. This strain exhibits excellent salt tolerance and low endotoxin properties. The production strain constructed from it has extremely high product synthesis capabilities, enabling high-concentration, high-intensity industrial fermentation production.

The invention discloses a method for preventing and treating sclerotinia rot of colza by antagonistic trichoderma strains, and relates to the technical field of agricultural disease prevention and control, and the method comprises the following specific steps: S100, strain screening and mutagenesis: separating trichoderma strains from rhizosphere soil of colza in different environments, primarily screening strains with antagonistic action on sclerotinia sclerotiorum by a plate confrontation method, and carrying out mutagenesis on the strains with antagonistic action on sclerotinia sclerotiorum; carrying out chemical mutagenesis treatment on the primarily screened strains, carrying out confrontation culture on the primarily screened strains and sclerotinia sclerotiorum again, screening out high-yield antagonistic substances with larger inhibition zones and mutant strains with strong stress resistance, and culturing to obtain trichoderma fermentation liquor; by obtaining the trichoderma strains which can keep efficient antagonism and strong stress resistance under different environmental conditions, the stability of the trichoderma strains on disease control is enhanced, so that the rape can effectively resist invasion of sclerotiniose under different environmental conditions in the growth process, and the disease resistance of the rape is improved. And antagonistic active substances are extracted to prepare a biological fertilizer carrier, and the biological fertilizer carrier is applied to the planting process of oilseed rape, so that the growth and reproduction of sclerotinia sclerotiorum are effectively inhibited.

The present disclosure relates, in general terms, to directed evolution, and more specifically to compositions and methods for phage-assisted directed evolution in microbes. In one embodiment, there is provided a method for directed molecular evolution, the method comprising: a) introducing a propagation-defective phage vector into a first host cell (mutagenic host) competent to propagate the phage vector, wherein the first host cell comprises a gene construct of interest (GOI) to be evolved; and wherein the phage vector allows for (i) expression of an error-prone DNA polymerase in the first host cell for mutagenesis, and (ii) replication and packaging of the GOI into infectious phage particles; b) incubating the first host cell under conditions for replication and mutagenesis of the GOI and release of phage particles comprising mutated GOIs; c) infecting a second host cell (selection host) with phage particles from step b); and d) selecting for a desirable function of the GOI in the second host cell.

A wheat variety designated 6PYKM33B, the plants and seeds of wheat variety 6PYKM33B, methods for producing a wheat plant produced by crossing the variety 6PYKM33B with another wheat plant, and hybrid wheat seeds and plants produced by crossing the variety 6PYKM33B with another wheat line or plant, and the creation of variants by backcrossing, mutagenesis or transformation of variety 6PYKM33B are disclosed. Methods for producing other wheat varieties or breeding lines derived from wheat variety 6PYKM33B and to wheat varieties or breeding lines produced by those methods are also provided.

The invention discloses a breeding method of lactic acid bacteria with high phenyllactic acid yield, and relates to the technical field of lactobacillus breeding. The invention provides a method for breeding lactic acid bacteria by using a normal-pressure room-temperature plasma (ARTP) mutagenesis technology, which can be used for simply, quickly and effectively screening lactic acid bacteria strains with high yield of phenyllactic acid, and has industrial application value.

A wheat variety designated 6PHQB77B, the plants and seeds of wheat variety 6PHQB77B, methods for producing a wheat plant produced by crossing the variety 6PHQB77B with another wheat plant, and hybrid wheat seeds and plants produced by crossing the variety 6PHQB77B with another wheat line or plant, and the creation of variants by backcrossing, mutagenesis or transformation of variety 6PHQB77B are disclosed. Methods for producing other wheat varieties or breeding lines derived from wheat variety 6PHQB77B and to wheat varieties or breeding lines produced by those methods are also provided.