418 results about "Mutant gene" patented technology

The invention belongs to the technical field of biology, and relates to an escherichia coli engineering strain for producing L-isoleucine through a methyl malic acid way as well as a construction method and application of the escherichia coli engineering strain. According to the invention, Escherichia coli BW25113 is used as a chassis strain, and a methyl malic acid synthase high-activity mutant gene cimA3.7, an isopropyl malic acid isomerase gene GsleuCD, a 3-isopropyl malic acid dehydrogenase gene AfleuB and a leucine dehydrogenase gene Lsleudh are over-expressed; a methyl malic acid absorption protein gene is over-expressed, and a branched chain amino acid transport system is modified to improve the exosome of the L-isoleucine; all methyl malic acid pathway related genes are integrated to a genome of a chassis strain, and a plasmid-free L-isoleucine production strain is constructed; the copy number of a key gene on a genome is optimized, and the yield of the engineering strain L-isoleucine is increased by introducing a non-oxidative glycolysis approach. The yield of the L-isoleucine after the engineering strain is fermented for 34 hours in a fermentation tank is 56.6 g / L.

The invention discloses a genetically engineered bacterium and an application of the genetically engineered bacterium in production of cis-3-hydroxy-L-proline. According to the genetically engineered bacterium, a proline dehydrogenase gene putA and a proline transporter gene putP in a starting bacterium are silenced, and meanwhile, a gamma-glutamyl kinase mutant gene proBD107N, a gamma-glutamyl phosphate reductase gene proA and a cis-3-hydroxy-L-proline hydroxylase gene P3H are subjected to overexpression. And by comparing a plurality of common escherichia coli, the cis-3-hydroxy-L-proline hydroxylase gene P3H and different gamma-glutamyl kinase mutant genes, the highest yield combination is preferably selected. The strain takes glucose as a raw material, so that the production cost is greatly saved, and the strain has a relatively good industrial utilization value.

The invention discloses a male sterility gene ZmUCE4 and application thereof in creating a male sterility line of corn, and belongs to the field of plant biotechnology breeding. According to the invention, site-directed mutagenesis of the ZmUCE4 gene in wild type corn is carried out through a CRISPR / Cas9 gene editing technology, pollen development abnormality and abortion can be caused, complete male sterility is caused, and it is proved that the ZmUCE4 gene has a regulation and control function on corn male reproductive development. Through offspring screening, a sterile line without transgenic components can be obtained, a stable maize male sterile line is created, and the method has important significance on maize male fertility control and hybrid seed production. The invention also designs a functional molecular marker aiming at the obtained uce4 male sterility mutant gene, and has important application value in maize male sterility line cultivation, sterile hybrid seed production and molecular marker-assisted selection.

The invention relates to the technical field of gene engineering, in particular to an L-rhamnose isomerase mutant, a recombinant plasmid, a mutant strain and application. The amino acid sequence of the mutant is as shown in SEQ ID NO.4, and the nucleotide sequence of the coding gene is as shown in SEQ ID NO.3. A specific mutant gene sequence is designed, a recombinant plasmid pET28a (+)-L-Rhi is successfully constructed, the gene sequence is connected between enzyme cutting sites BamH I and Hind III of an escherichia coli expression vector pET-28a (+) to construct a mutant expression vector (the recombinant plasmid pET-28a (+)-L-Rhi), the mutant expression vector is transformed into an escherichia coli BL21 competent cell, a mutant strain is obtained, and the recombinant plasmid pET-28a (+)-L-Rhi is obtained. The obtained mutant strain can overexpress L-rhamnose isomerase, the conversion rate of D-allose is remarkably improved, the thermal stability of the enzyme is remarkably improved through the design of mutation sites, and the half-life period is effectively prolonged.

The invention relates to the technical field of gene engineering, in particular to an L-rhamnose isomerase mutant, a recombinant plasmid, a mutant strain and application. The amino acid sequence of the mutant is as shown in SEQ ID NO. 2, and the nucleotide sequence of the coding gene is as shown in SEQ ID NO. 1. A specific mutant gene sequence is designed, a recombinant plasmid pET28a (+)-L-Rhi is successfully constructed, the gene sequence is connected between enzyme cutting sites BamH I and Hind III of an escherichia coli expression vector pET-28a (+) to construct a mutant expression vector (the recombinant plasmid pET-28a (+)-L-Rhi), the mutant expression vector is transformed into an escherichia coli BL21 competent cell, a mutant strain is obtained, and the recombinant plasmid pET-28a (+)-L-Rhi is obtained. The obtained mutant strain can overexpress L-rhamnose isomerase, the conversion rate of D-allose is remarkably improved, the thermal stability of the enzyme is remarkably improved through the design of mutation sites, and the half-life period is effectively prolonged.

The invention discloses a bifunctional flavin adenine dinucleotide synthetase mutant and an application of the bifunctional flavin adenine dinucleotide synthetase mutant in FAD synthesis. The mutant disclosed by the invention is RFK / FADSC18R or RFK / FADSC18R-R46H, and the structural formula of the mutant is as shown in the specification. The amino acid sequence of the RFK / FADSC18R is as shown in SEQ ID NO. 15, and the amino acid sequence of the RFK / FADSC18R-R46H is as shown in SEQ ID NO. 16. A genetically engineered bacterium carrying the bifunctional flavin adenine dinucleotide synthetase mutant gene plasmid is used for producing flavin adenine dinucleotide by using glucose as a substrate through a simple fermentation process under a shake flask aerobic condition, and the FAD yields of strains XF02 and XF03 containing mutant genes are 79.31 mg / l and 167.56 mg / l in sequence; and compared with a strain XF01 containing a non-mutated gene, the mutant gene is improved by 58.62% and 235.12% respectively. A microbial'cell factory 'is constructed through a metabolic engineering strategy, and the modified microorganisms can generate required natural products in microbial cells by utilizing low-price raw materials. The progress not only reduces the production cost of the FAD, but also improves the environmental sustainability of the production process of the FAD.

The application discloses a kind of fungal laccase mutant Lcc5-G and its expression strain and application.The application is based on the fungal laccase from Coprinopsis cinerea heterologous expression since, by site-directed mutagenesis, obtain mutant gene.After fungal induction expression containing mutant plasmid, obtain laccase mutant enzyme Lcc5-G with improved specific activity, stability and AFB1 removal efficiency.When ABTS is used as substrate, the specific activity of the mutant is improved by 3 times, and the stability of the mutant enzyme is improved to 5 times of the original enzyme at 45 DEG C and pH 7.The mutant has potential application value in oxidizing aflatoxin.

The invention discloses escherichia coli recombinant engineering bacteria for producing citicoline as well as a construction method and application of the escherichia coli recombinant engineering bacteria, and belongs to the technical field of biology. A genome cytidine deaminase coding gene cdd is knocked out on the basis of Escherichia coli K-12 MG1655, a temperature control expression vector PBV220 is used for expressing a SpnCCT-SpnCKI-pRpLpyrG mutant gene cluster, the expression of choline transporter protein BetT is enhanced, the gene locus of Escherichia coli ptsH-ptsI-crr is destroyed, meanwhile, a glucose permease gene glf and a glucokinase gene glk from Zymomonas mobilis are introduced, and the mutant gene cluster of the Escherichia coli K-12 MG1655 is obtained. The escherichia coli recombinant engineering bacterium ZMCB02NCL capable of efficiently biosynthesizing citicoline is obtained, and the preservation number of the escherichia coli recombinant engineering bacterium ZMCB02NCL is CCTCC NO: M 2025483.

Using chemical genetic screening, we discovered a small molecule Cellulosin (aka endosidin20 or ES20) that causes cell swollen and inhibits plant growth, but does not disrupt global vesicle trafficking. By doing mutant screening, we obtained multiple alleles of Arabidopsis thaliana that are resistant to Cellulosin inhibition in growth. Those mutated amino acid residues are conserved across plant species. Cellulosin targets a group of cellulose synthases (CesAs) of Arabidopsis thaliana by binding to a conserved domain essential for the catalytic activity of CesA. Cellulosin may target and inhibit all subtypes of CesAs in plants. The present invention relates to Cellulosin, a cellulose synthase inhibitor, its analogs or derivatives as a broad-spectrum herbicide. The mutated genes, their protein products and a cell or a plant having those mutated genes or expressing those protein products are within the scope of this disclosure.

The invention discloses a sorghum brown midrib mutant gene bmr34 related to high digestibility and application of the sorghum brown midrib mutant gene bmr34. The haplotype of the mutant gene bmr34 can specifically reduce the lignin content by 2.99% without affecting the biological yield. The invention provides the KASP marker which can accurately locate the bmr34 gene of sorghum and is closely linked with the bmr34 gene of sorghum, so that the breeding efficiency can be greatly improved, the breeding process is accelerated, and the KASP marker has important theoretical and practical significance for improving the quality of sorghum feed.

The invention discloses a rice seed dormancy gene OsPHS1 and application of a protein encoded by the gene OsPHS1, and belongs to the technical field of plant genetic engineering, and the gene and the protein encoded by the gene are used for regulating the dormancy of rice seeds. The nucleotide sequence of the gene is shown as Seq ID No: 1, the CDS sequence is shown as Seq ID No: 2, and the coded protein sequence is shown as Seq ID No: 3. The function of the rice seed dormancy gene OsPHS1 is verified by cloning and identifying the rice seed dormancy gene OsPHS1, and research finds that the dormancy of rice seeds can be remarkably reduced by knocking out or mutating the OsPHS1 gene, and the dormancy of the rice seeds can be improved to a certain extent by overexpressing the gene; the invention plays an important role in developing rice varieties with moderate dormancy.

Disclosed herein is a novel Cas9 protein. Further described herein are fusion proteins, compositions, and methods comprising the same. The novel Cas9 protein may be used, for example, in compositions and methods for modulating expression of a gene, for correcting a mutant gene, and for treating a disease.

The present invention relates to a MeCP2 gene-specific trans-splicing ribozyme, and a use thereof. The trans-splicing ribozyme according to the present invention replaces the RNA of a mutant MeCP2 gene, which causes Rett syndrome, with a wild type MeCP2 RNA, so as to reduce the expression of the mutant MeCP2 protein and increase the expression of the wild type MeCP2 protein, and enables regulated expression so that wild type MeCP2 expression can be prevented from exceeding physiological levels, and thus can be effectively used for preventing or treating Rett syndrome.

In traditional plant breeding approaches, chemical mutagenesis may be utilized to introduce nucleotide substitutions at random in the genome of a plant, i.e. without possibilities to control the sites of nucleotide changes. Because of genome complexities, the statistical probability is extremely little when it comes to finding a predetermined nucleotide substitution. The present invention, however, demonstrates how a novel, alternative use of digital polymerase chain reaction (dPCR), preferably droplet dPCR (ddPCR), is developed to exploit finding of specific nucleotide substitutions in mutated genes. The entire platform comprises a screening method with a library of mutagenized organisms, digital PCR-based systems and a set-up to propagate and analyze identified, mutated organisms.

The invention relates to a gene ZmILR1 for controlling the size of a corn kernel as well as a molecular identification method and application of the gene ZmILR1, and belongs to the technical field of plant genetic breeding and functional gene research. The ZmILR1 gene encodes an IAA-amino acid hydrolase, mutation of the IAA-amino acid hydrolase causes corn kernels to become smaller, and overexpression of the gene can create a corn material with increased kernel length, kernel width and hundred-kernel weight. A functional molecular marker A1A4 is developed according to the sequence difference of the mutant gene and a wild type gene at the DNA level, and can be used for rapid identification and screening of small-grain corn materials. The invention provides a theoretical basis and an application tool for analyzing a molecular mechanism of the corn grain size and developing molecular marker-assisted breeding and hybrid seed breeding, and provides important gene resources and technical support for high-yield and high-quality molecular breeding of corn.

The invention discloses a corn ALS mutant gene and application of the corn ALS mutant gene in herbicide resistance. The invention provides a method for improving the herbicide resistance of corn, which comprises the following steps: mutating 493th nucleotides of a ZmALS1 gene and a ZmALS2 gene in a corn genome from C to G so as to improve the herbicide resistance of the corn, the nucleotide sequence of the ZmALS1 gene is shown in SEQ ID No. 1; the nucleotide sequence of the ZmALS2 gene is shown in SEQ ID No. 2. Specific sites in corn ZmALS1 and ZmALS2 serve as sgRNA recognition sites on the basis of the principle of a base editing technology, a single base replacement editing vector capable of simultaneously targeting the ZmALS1 and ZmALS2 is designed, the gene editing vector is stably transformed through agrobacterium to obtain a transgenic plant, and the resistance to herbicides is remarkably improved.

An Interferon Gamma Inducible Protein 16 (IFI16) mutant gene and its use as a marker for predicting, diagnosing, or prognosticating risk or severity of chronic liver disease is described. As a result of performing genomic analysis on NAFLD and NASH patient groups, it was confirmed that the frequency of IFI16 single-nucleotide variants (SNVs) including rs2276404, rs73021847, rs7532207, and rs6940 was increased, and the expression of the IFI16 mutant gene was increased depending on the disease stage of liver disease. The IFI16 SNV was highly expressed in infiltrating macrophages, playing a role in macrophage-induced inflammatory processes, and the IFI16 variant bound more strongly to dsDNA than wild-type IFI16, exacerbating the impaired mitochondrial DNA-sensing response signaling of the IFI16-PYCARD-CASP1 pathway. Thus, the IFI16 mutant gene may be used for predicting, diagnosing, or prognosticating risk or severity of chronic liver disease.

The invention belongs to the field of biotechnology and environmental governance, and particularly relates to a manganese peroxidase mutant modified through semi-rational design and application of the manganese peroxidase mutant to straw degradation. On the basis of Irpex lacteus MnP, a core site G189 is screened out through structural analysis and alanine scanning, a G189A single mutant (glycine-alanine) is constructed, the G189A single mutant is free of Mn < 2 + > dependence, the enzyme activity reaches 15.2 U / mL (about 130% higher than that of a wild type), and the catalytic efficiency is improved by 2.1 times. Meanwhile, the mutant gene is introduced into bacillus subtilis to realize efficient extracellular secretion, the straw lignocellulose depolymerization can be effectively promoted, the application value in the fields of agricultural straw recycling and the like is remarkable, and the wide market application prospect is achieved.

The present invention discloses an EPSPS enzyme mutant, a nucleic acid molecule, an expression cassette, an expression vector, a recombinant bacterium or a recombinant cell and an application thereof, and relates to the technical field of plant genetic engineering. The EPSPS enzyme mutant provided by the present invention can effectively solve the problem of non-selective damage to crops by herbicides such as glyphosate, and provides a new way to cultivate glyphosate-resistant crop varieties. At the same time, the EPSPS enzyme mutant provided by the present invention also has high practicality and promotion value, can improve the weeding effect in agricultural production, reduce the cost of weeding, and promote the increase of crop yield. In addition, the present invention also provides an expression cassette for expressing the EPSPS enzyme mutant, which contains an EPSPS mutant gene that confers glyphosate resistance to various plants such as soybeans and rice.

The present invention relates to a mutant gene of rice OsSPL10 gene and its application. The nucleotide sequence of the mutant gene is shown in SEQ IN NO.1. This mutant gene can endow rice with resistance to glufosinate herbicide. The present invention uses the EMS chemical mutagenesis technology to treat the rice variety "Yangxian 9B", successfully induces the mutation of the OsSPL10 gene, and this mutation causes the 225th amino acid in the amino acid sequence of the encoded protein to change from cysteine to tyrosine. At the same time, the present application develops a KASP molecular marker for this mutation site. Through molecular marker detection, field glufosinate resistance screening and verification, it is proved that rice with this mutant gene can improve glufosinate resistance. This gene has significant application potential in agricultural production, can reduce the use of herbicides and improve crop yield and quality.

The invention relates to the technical field of biology, and particularly discloses a method for reducing the plant height of corn. The corn contains the ZmD9 mutant gene or the protein coded by the ZmD9 mutant gene, so that the plant height and the ear height of the plant can be reduced; the ZmD9 mutant gene takes a nucleotide sequence of a wild type ZmD9 gene as a reference sequence, and comprises 64-91 base deletion mutation in a CDS (Coding Sequence) region. The method is beneficial to improving the plant height and density tolerance characters of corn varieties, and has important breeding application potential.

The invention discloses yarrowia lipolytica with high yield of beta-carotene as well as a construction method and application of the yarrowia lipolytica. According to the yarrowia lipolytica engineering bacterium, geranyl diphosphate synthase gene xdGPS, phytoene dehydrogenase gene CarB, phytoene cyclization / phytoene synthesis bifunctional enzyme mutant gene GarRPY27R, acetyl-coenzyme A synthetase mutant gene ACSL641P and pyruvate ferredoxin oxidoreductase gene nifJ are integrated and expressed on a chromosome, and the yarrowia lipolytica engineering bacterium is obtained. Meanwhile, a 3-hydroxy-3-methylglutaryl CoA reductase gene HMGR (3-hydroxy-3-methylglutaryl CoA reductase) derived from the yarrowia lipolytica strain is subjected to overexpression; the yield of the beta-carotene is increased to 13.186 g / L, and the production efficiency is 0.14 g / L / h.

The invention discloses a method for improving citrus liberobacter asiaticum resistance by using a CsZRK1 gene, the CsZRK1 gene is mutated to improve the liberobacter asiaticum resistance of citrus plants, and the nucleotide sequence of the CsZRK1 gene is as shown in SEQ ID NO: 1. The CsZRK1 gene coding sequence is cloned, the CRISPR / Cas9 mutant vector is constructed, and then the citrus is converted, so that the incidence degree of the hairy root huanglongbing of the obtained transgenic plant is obviously reduced, and the CsZRK1 gene has a great application value for huanglongbing-resistant breeding of the citrus, and can be used as a candidate gene for huanglongbing-resistant breeding with a plurality of huanglongbing-resistant and susceptible genes.

The application discloses a carbonyl reductase mutant and application thereof in preparation of (R)-8-chloro-6-hydroxyoctanoate compounds. The application relates to a mutant of carbonyl reductase with improved catalytic performance and stereoselectivity after rational molecular modification, a recombinant expression plasmid containing the mutant gene of the enzyme, a recombinant expression transformant, a preparation method of the recombinant enzyme, and application of the recombinant enzyme or the recombinant cell as a catalyst in asymmetric reduction of 8-chloro-6-carbonyloctanoate compounds (I) to prepare (R)-8-chloro-6-hydroxyoctanoate compounds (II), in particular, in an intermediate (R)-8-chloro-6-hydroxyoctanoate methyl ester of thioctic acid. The disclosed carbonyl reductase SsCR mutant has the advantages of high reaction efficiency and high catalytic activity, and exhibits the advantages of high substrate concentration, low catalyst consumption and short reaction time in the process of catalytic preparation of the compound (II).

The invention discloses an N-acetyl glucosamine 2-epimerase mutant as well as preparation and application of the N-acetyl glucosamine 2-epimerase mutant. The mutant enzyme comprises an amino acid sequence as shown in SEQ ID No.3. The preparation method comprises the following steps: by taking a recombinant vector containing a Sumo enhancing element and a wild type N-acetyl glucosamine 2-epimerase gene as a template, carrying out PCR (Polymerase Chain Reaction) by adopting a mutation primer to obtain a mutant gene segment; transforming the mutant gene segment into an engineering bacterium to obtain a recombinant bacterium for expressing the N-acetyl glucosamine 2-epimerase mutant protein; culturing recombinant bacteria, collecting and crushing thalli, centrifuging thallus crushing liquid, and taking supernatant, so as to obtain crude enzyme liquid containing the enzyme mutant; the thermal stability of the wild-type enzyme is improved through point mutation of specific amino acid sites, and the substrate affinity and the catalytic efficiency of the mutant are superior to those of the wild-type enzyme. The mutant can be used for efficient catalytic preparation of lactulose, and has the advantages of few byproducts, high product yield and the like.

This invention discloses a laccase mutant, Lcc5-I479T, its expression strain, and its applications. Using laccase from *Coprinopsis cinerea* as the starting enzyme, this invention obtained the mutant gene through molecular docking and positional analysis. After induction expression in engineered bacteria containing the mutant gene, the stable laccase mutant enzyme Lcc5-I479T was obtained. Using ABTS as a substrate, the mutant enzyme Lcc5-I479T showed a stable increase in activity to 8-20 times that of the starting enzyme at 35-50℃. This mutant enzyme has potential application value in the oxidative transformation of aflatoxin.

The invention relates to the technical field of molecular biology, in particular to a multiplex PCR (polymerase chain reaction) molecular marker amplification system for identifying Waxy mutant genes of wheat, a product and application of the multiplex PCR molecular marker amplification system. The multiple PCR molecular marker amplification system developed by the invention has the advantages of stable amplification and good specificity, realizes simultaneous genotype identification of three waxy genes Wx-A1, Wx-B1 and Wx-D1 through one-time PCR, is simple, convenient and rapid in detection process and high in flux, can accurately and efficiently screen out waxy wheat materials containing Waxy mutant genes, and has good application prospects. The waxy wheat breeding molecular marker-assisted selection efficiency and accuracy can be improved, the breeding process is shortened, and technical support can be provided for waxy wheat breeding work.

Compositions and methods for detecting structural variations (SVs) in target genes or for genetic mapping of movable transposable elements are disclosed, the target genes relating to disease pathologies commonly found in large Mendelian genomics projects, and the movable transposable elements relating to genetic diseases, cancer, and aging. The method comprises: (i) contacting a sample containing genomic DNA with a DNA endonuclease for an effective amount of time to cleave the genomic DNA into fragments, the genomic DNA being uncrosslinked; (ii) subjecting the fragments obtained from step (b) to a DNA ligase to obtain circularized DNA; (iii) subjecting the circularized DNA to reverse PCR amplification containing a reverse primer, wherein the reverse primer is designed to match a expected wild-type sequence near a suspected mutant locus in the gene; and (iv) sequencing the amplified products. Exemplary conditions include Bardet-Biedel syndrome; severe upper and lower limb defects; retinitis pigmentosa; syndromic microcephaly; spastic paraplegia; and atypical hemolytic uremic syndrome.

The invention discloses an organ-like drug resistance prediction method and device and a storage medium, and relates to the technical field of bioinformatics, and the method comprises the steps: S1, constructing an initial prediction model; s2, acquiring a training data set; s3, training an optimization prediction model; s4, acquiring related data of a to-be-predicted drug; s5, obtaining a prediction result of the drug resistance of the to-be-predicted drug; according to the method, the drug resistance of the organoid to the drug can be predicted more accurately. By fusing multi-dimensional features of gene mutation, target mutation and drug functional groups, the understanding and learning ability of the model to the drug resistance mechanism is enhanced, and the reliability of drug resistance prediction is improved. The method not only can accurately capture key information of influence of gene and target mutation on drug resistance, but also can highlight unique mutant genes of the organoid on drug resistance by comparing feature differences of the organoid and a common cell line, so that an efficient and accurate calculation framework is provided for drug resistance detection.

The invention belongs to the field of genetic engineering, and relates to a mung bean VrLAL1 (LANCEOLATE LEAVES1) protein, a mung bean VrLAL1 gene and application of the mung bean VrLAL1 protein and the mung bean VrLAL1 gene in regulation and control of leaf size and pod length, M5311 wild species and al1 mutant species are hybridized, and the VrLAL1 gene is finely positioned on the basis of an existing mung bean molecular marker. The method comprises the following steps: selecting a plurality of candidate genes in a candidate interval, simultaneously performing transcriptome sequencing analysis on a mutant, screening and identifying a plurality of candidate genes in the candidate interval according to a transcriptome result, finding a mutant gene VrLAL1 gene, designing a primer, and performing PCR (Polymerase Chain Reaction) first cloning to obtain the VrLAL1 gene. The VrLAL1 gene has an obvious effect on regulation and control of organ size, leaf development and pod development, and can be used for variety improvement of legume crops.