74 results about "Mutation rate" patented technology

The invention belongs to the technical field of biology and new medicine, and discloses a method for constructing a myxobacteria expression chassis with genetic stability and application of the myxobacteria expression chassis. Through gene deletion and overexpression analysis, it is verified that the spontaneous mutation rate of a strain can be reduced by deletion of a TLS pathway and overexpression of RecA, and a myxobacteria strain 2K7 with genetic stability is further constructed on the basis. The spontaneous mutation rate of the new strain is reduced by 11.5 times, and the transformation capability of growth plasmids of the strain is obviously improved. According to the research, the genetic stability of the myxobacteria is improved for the first time through a repair way after modification and replication, and the research method and the research result are innovative.

The invention discloses a horizontal centrifuge real-time PID gain optimization control method based on an improved adaptive genetic algorithm. The method comprises the steps that a chromosome population is defined based on PID gain of a horizontal centrifuge; constructing a first fitness function based on the first index of the horizontal centrifuge, and calculating the fitness of individuals in the chromosome population; and screening parent individuals by using a champion for genetic generation of offspring, obtaining the crossover rate and mutation rate of the individuals based on the fitness of the individuals in the genetic process, repeating the genetic process until convergence, and applying the PID gain corresponding to the current optimal individual to control the horizontal centrifuge. In the process, the parent is screened, and the genetic crossover rate and the mutation rate are adaptively adjusted, so that the PID parameters are converged more quickly, and the robustness is high.

The invention discloses a construction method of a glycogen accumulation disease type 3 (GSD III) zebrafish F0-generation model and application of the model in drug screening, sgRNA combination and Cas9 protein are mixed, the mixture is jointly injected into a single cell stage embryo of wild type zebrafish, and the F0-generation zebrafish model generating diallele mutation is obtained through cultivation. The sgRNA combination comprises a first targeting sequence and a second targeting sequence aiming at the agla gene, and a third targeting sequence and a fourth targeting sequence aiming at the aglb gene. The technical barrier that the construction period of a traditional GSD III zebrafish double-knockout homozygous strain is as long as 6-12 months is broken through, through the screened high-activity sgRNA combination and the adoption of a high-concentration Cas9 protein co-injection strategy in the single cell period, the extremely high biallele mutation rate is achieved in the F0 generation, and the high-concentration Cas9 protein co-injection strategy is adopted in the single cell period. The defects that the traditional F0 generation is high in chimeric degree and unstable in phenotype are effectively overcome.

The invention belongs to the technical field of job shop scheduling, and particularly relates to a self-learning job shop scheduling method meeting waiting time constraint, which comprises the following steps: S0, constructing a job shop scheduling problem model with waiting time constraint; the method comprises the following steps: S1, acquiring job shop scheduling problem data, a configuration algorithm and operation parameters; s2, constructing chromosome individuals, generating chromosomes and initializing a population; s3, calculating the fitness value of each chromosome individual; s4, forming a new generation of population; s5, combining the fitness information of the current population, dynamically selecting a crossover rate Pc through a Q learning algorithm, and performing crossover operation on the population; s6, dynamically determining a mutation rate Pm in the same parameter combination space by using a Q learning algorithm, and performing mutation operation on the crossover progeny to generate an updated population; and S7, judging whether an iteration termination condition is met or not. According to the method, a feasible and near-optimal scheduling scheme can be efficiently generated on the premise of ensuring that the inter-process waiting time constraint is met.

Provided are a method for large-scale synthesis of a long-chain RNA and a method for site-specific modification of the long-chain RNA. The method for large-scale synthesis of a long-chain RNA comprises: designing short RNA fragments and splint DNA fragments; ligating; capping; and removing the splint DNA fragments and other steps. A large number of short RNA fragments and different splint DNA fragments are chemically synthesized, and then the different short RNA fragments are ligated by a biological method so as to form a target long-chain RNA. The product long-chain RNA has a low mutation rate, a plurality of the short RNA fragments can be assembled in a single reaction, and the long-chain RNA can be synthesized at a high throughput so as to fulfill the large-scale production of the long-chain RNA. In addition, by chemical modification of the short RNA fragments, the site-specific modification of the long-chain RNA can be realized.

According to an example aspect of the present invention, there is provided a method for generating a transmission timeline, the method comprising: determining, based on SNP information, SNP evolutionary distance from a reference genome for each sample; determining, based on the SNP information, SNP evolutionary distance between each sample; and generating, based on: the SNP information, the SNP evolutionary distances from the reference genome, the SNP evolutionary distance between the samples, the mutation rate, generation rules and the corresponding timestamps; a dated phylogenetic tree, said tree comprising sample nodes) and non-sample nodes, wherein each sample may correspond to a node, for example.

The invention discloses an HTR2 promoter, a CRISPR / Cas9 gene editing vector and application of the CRISPR / Cas9 gene editing vector in plant gene editing, and belongs to the technical field of biology. According to the present invention, the HTR2 promoter having the nucleotide sequence represented by SEQ ID NO: 1 can efficiently drive the transcription of the Cas9 gene in the CRISPR / Cas9 gene editing vector, can edit the target gene, can significantly improve the gene editing efficiency, and can reduce the off-target effect and the chimera generation; the homozygous mutation rate of the CRISPR / Cas9 gene editing vector of the Cas9 gene driven by the HTR2 promoter is obviously higher than that of common promoters such as a CaMV35S promoter, and the CRISPR / Cas9 gene editing vector has a better application prospect in the field of plant gene editing.

The present invention belongs to the technical field of sequencing in gene therapy. Provided is a detection method for a rare-mutation BRAF gene. The sequencing method comprises: during an amplification process of the BRAF gene of a target sample fragment, adding a blocking primer matched with a wild-type template in the target sample fragment, so as to bind the blocking primer to a denatured wild-type template; and performing sequencing to obtain a sequencing result corresponding to the target sample fragment. During the process of making a sequencing template, the present invention uses the blocking primer to inhibit the wild-type template of the BRAF gene during the amplification process, so as to relatively increase the proportion of a mutant product, thereby achieving the purpose of accurately detecting samples with a lower mutation rate. Therefore, the present method is of an important significance for detecting rare mutations by using a Sanger sequencing method.

The application provides a design method and device of a wave-absorbing composite material based on a genetic algorithm, and the method comprises the following steps: based on a plurality of different types of wave-absorbing materials, random coding is performed to obtain a plurality of genetic individuals, and an initial population is formed; the reflectivity of each genetic individual in the population is calculated; the fitness of each genetic individual is evaluated; according to the number of bits corresponding to the data variable in the coding and the current population evolution generation number, the mutation rate of each genetic individual is calculated; the genetic individual with the minimum fitness is retained, and the other genetic individuals are crossed and mutated by using the mutation rate to obtain a new generation population, and the calculation of the reflectivity of each genetic individual in the population is performed on the new generation population, until the termination condition of the genetic algorithm is met, so that the genetic individuals in the new generation population obtained form the wave-absorbing composite material. According to the scheme, the mutation rate can be gradually increased to accelerate the optimization speed under the premise of ensuring the early rapid convergence, and the rapid convergence and rapid optimization of the genetic algorithm are realized.

The application provides a method, device, equipment, medium and program product for determining suspension system parameters. In the method, after obtaining an initial crossover rate, an initial mutation rate and a multi-objective optimization model of a suspension system, an initial population is determined according to a constraint condition of the multi-objective optimization model, and then the multi-objective optimization model is solved according to a non-dominated sorting genetic algorithm, an algorithm parameter dynamic optimization model, the initial population, the initial crossover rate and the initial mutation rate to obtain target suspension system parameters. The algorithm parameter dynamic optimization model is a preselected deep Q network model for determining a crossover rate increment and a mutation rate increment according to state data of the population. In the solving process, the algorithm parameter dynamic optimization model dynamically adjusts the crossover rate and the mutation rate of the non-dominated sorting genetic algorithm according to the state data of the population, which can improve the solving efficiency and thus improve the efficiency of determining the suspension system parameters.

The invention discloses a construction method and application of a kluyveromyces marxianus mutant, and belongs to the field of synthetic biology and molecular biology. According to the method, single-stranded DNA binding protein and cytosine deaminase pmCDA1 are fused, a random base editing system is constructed, and whole-genome efficient C-T / G-A mutation is realized in kluyveromyces marxianus by taking MCM2-7 as a verification target. The system does not need a specific target or an exogenous DNA template, the mutation efficiency is high, the distribution is wide, the mutation rate is improved by 303.1 times compared with that of a control group through optimal combination, and the application potential of kluyveromyces marxianus in industrial production is expanded. The method is combined with an efficient screening system, mutant strains with the intracellular protein expression quantity remarkably improved are screened out, the constructed mutation system is not only suitable for kluyveromyces marxianus cell factory transformation, but also can be popularized to genome evolution of other yeasts or eukaryotic hosts, and a new strategy is provided for industrial microorganism breeding and protein engineering.

The present invention discloses a quality inspection method for adapter primers used for high-throughput sequencing and a high-throughput sequencing method. The quality inspection method comprises: mixing an adapter primer to be tested with a 3' adapter to perform a ligation reaction, adding an extension primer to perform an extension reaction to form a second DNA strand, adding a 5' adapter to perform a ligation reaction, performing PCR amplification to obtain an MGI library, and sequencing and data analysis of the MGI library based on an MGI sequencing platform. The 3' adapter and 5' adapter are adapters that match the MGI sequencing platform. The present invention designs a quality inspection method for adapter primers used for high-throughput sequencing, designs an MGI library construction strategy for the adapter primers to be tested, and performs sequencing and data analysis based on the MGI sequencing platform. The method can accurately analyze the integrity, mutation rate, deletion rate, and insertion rate of the adapter primers, evaluate the quality of the adapter primers, and thus effectively perform quality inspection on high-throughput sequencing adapter primers.

The application discloses a plant and animal evaluation method based on a genetic algorithm, and the method comprises the following steps: determining initial genes to be evaluated according to evaluation indexes, and determining a chromosome where the initial genes are located as an initial chromosome; setting a preset mutation rate for a position where each gene on the initial chromosome is located, and increasing the preset mutation rate corresponding to the position where the initial gene is located to obtain a target mutation rate; performing genetic simulation on the initial chromosome according to a preset crossover rate, the preset mutation rate and the target mutation rate to obtain a target chromosome; inputting gene coding of the target chromosome into a preset neural network model; determining an evaluation score of the target chromosome in the preset neural network model; and if the evaluation score is higher than a preset threshold, determining that a gene code corresponding to the evaluation score is a high-quality gene. According to the method, genetic simulation is performed in a directional manner according to a target mutation direction, and the problem that the number of iterations is too large and the target solution is not high-quality in the prior art is solved.

The present invention belongs to the technical field of microbial mutagenesis, and particularly relates to a microbial mutagenesis breeding device and its application. The microbial mutagenesis breeding device provided by the present invention includes a cube structure and a transmission structure. The cube structure is wrapped with light-impermeable materials around, and ultraviolet lamps are arranged inside. The transmission structure includes a single sorting area and a mutagenesis area. The mutagenesis area is inserted into the cube structure through the insertion opening of the cube structure and is arranged perpendicular to the ultraviolet lamps. Microorganisms can be sorted singly through the first horizontal spiral conveyor pipe in the single sorting area and transported to the second horizontal spiral conveyor pipe in the mutagenesis area, so that the time and intensity of the microorganisms being irradiated by ultraviolet light are uniform, significantly reducing the mutagenesis lethality rate of the microorganisms and significantly increasing the positive mutation rate. The operation is simple, the workload is small, and the cycle is short. Moreover, by treating the microorganisms with a protective agent having a specific composition before single sorting, the mutation uniformity and the positive mutation rate can be further improved.

The invention relates to the technical field of strain breeding, in particular to a high-yield beta-glucan Meyrowia guilliermondii strain and application thereof. According to the present invention, the high-yield beta-glucan mutant strain obtained through ARTP mutagenesis has the name of Meyerozyma guilliermondii NCUASD7, has been preserved in Guangdong Microbial Culture Collection Center on November 28, 2025, and has the preservation number of CDMCC NO: 67365; aRTP mutagenesis is high in mutation rate, good in hereditary stability and safer to operate, a large number of mutation libraries can be obtained within a short time, high-throughput primary screening and shake flask secondary screening are conducted through a 24-deep-hole plate, a yeast mutant strain with the high beta-glucan yield capacity is obtained, then subculture is conducted on the high-yield mutant strain, the hereditary stability of the strain is verified, and the high beta-glucan yield is obtained. The mutant strain not only has the characteristic of high yield of beta-glucan, but also can maintain good genetic stability.

The present disclosure aims to provide a technique capable of accurately detecting a mutant gene and a mutation rate using capillary electrophoresis. A method for detecting a mutant gene according to the present disclosure classifies signal peaks included in a detected signal into a first group lower than a first threshold and a second group not lower than the first threshold, increases an injection voltage until the signal peak belonging to the first group becomes higher than or equal to the first threshold, and decreases the injection voltage after increasing the injection voltage until the signal peak belonging to the second group becomes lower than or equal to a second threshold higher than the first threshold.

The invention discloses a tissue culture method for reducing the somatic variation rate of bamboo reed by adding chitosan oligosaccharide. According to the method, 50-200 mg / L of chitosan oligosaccharide with the specific molecular weight of (3000-5000 Da) is added into a callus induction culture medium, and 1.5 mg / L of 2, 4-D and 0.2 mg / L of 6-BA are combined, so that the variation rate of somatic cells is reduced from 23.7% to 9.8%. The SSR molecular marker and flow cytometry prove that the genetic stability is remarkably improved, and the biomass of the regenerated plant is increased by 15-20%. The method is suitable for large-scale cloning propagation of energy plants.

The invention provides a primer and probe combination, a kit and a method for quantitatively detecting the JAK2V617F gene mutation rate, and the primer and probe combination comprises a primer and probe set targeting JAK2V617F mutation sites and a primer and probe set of reference genes GPI, according to the primer probe set targeting JAK2V617F mutation sites, the nucleotide sequence of an upstream primer of a specific mutation site is any one of SEQ ID NO.1-7, the nucleotide sequence of an upstream primer of a specific wild type site is any one of SEQ ID NO.9-14, the nucleotide sequence of a universal downstream primer is SEQ ID NO.8, and the nucleotide sequence of a probe is SEQ ID NO.15. The invention further discloses a kit for detecting the JAK2V617F mutation sites. According to the invention, the JAK2V617F mutation rate can be economically, simply, efficiently, sensitively, accurately and quantitatively detected, and the detection mutation rate is as low as 0.1%.

The invention provides a method for measuring the mutation rate of a sexual reproduction animal whole genome level nucleotide germline. The method comprises the following steps: (1) performing genome sequencing on a to-be-detected species to obtain sequences of all coding proteins of the to-be-detected species; (2) constructing a phylogenetic tree of a to-be-tested species; (3) obtaining the divergence time Tdivergence between the species to be detected and the sibling species; (4) optimizing the phylogenetic tree of the species to be tested; and (5) obtaining the annual germline mutation rate [mu] year of the species to be detected. The principle of the method is as follows: neutral regions or neutral sites are widely distributed in a genome, and mutations generated at the positions are generally not influenced by natural selection; the mutation rate of the germline can be calculated by analyzing the change of the variation frequency of the sites along with time. The method provided by the invention not only is widely applicable to sexual reproduction animal species with obtained genome or transcriptome data, but also is accurate and efficient, fills up the blank of the prior art, and has great significance in theoretical research and practical application of biomedical engineering.

The invention discloses a cancer genome variation prediction system based on multiple genetic operators, relates to the technical field of genetic variation detection, and aims to solve the problems that the traditional cancer genome variation prediction is mainly based on a static mutation rate and a single mutation type, the dynamic balance and nonlinear evolution of a tumor in mutation, selection and clone expansion processes are difficult to accurately reproduce, and the accuracy is poor. According to the cancer genome variation prediction method and the cancer genome variation prediction system, high-fidelity simulation and evolution reconstruction of the cancer genome are realized by fusing a multi-type mutation mechanism, fitness feedback and a polyclonal competition strategy. According to the method, through the synergistic effect of multiple genetic operators and dynamic parameter adjustment, the dynamic balance and nonlinear evolution of the tumor in the mutation, selection and clone expansion process can be accurately reproduced, and then the accuracy of cancer genome variation prediction is improved. The application provides a brand new technical approach for early screening of cancers, variation detection and precise medical treatment.

The present invention provides engineered T7 replisomes that contain one or more modified protein components, and E. coli based orthogonal DNA replication systems that contain such engineered T7 replisomes. Relative to known orthogonal replication systems, the engineered DNA replication systems of the invention are capable of evolving target polynucleotide sequence with enhanced mutation rates.

The invention discloses a double-end modified probe for detecting single nucleotide polymorphism as well as a design method and application of the double-end modified probe, and through the synergistic effect of thio-modification and locked nucleic acid modification and in combination with SNP sites and 3 '-end artificial mutation design, the distinction degree and detection sensitivity of the probe to wild types and mutant types are improved. Experiments show that the probe can detect a mutation proportion as low as 0.1%, the melting temperature difference between a wild type and a mutant type is greater than 4 DEG C, and the probe is suitable for multiple detection of drug-resistant genes or strain identification of pathogenic microorganisms such as mycobacterium tuberculosis and the like.

The invention relates to the technical field of biology, in particular to a directed evolution system and method. The system comprises an orthogonal transcription mutant, the orthogonal transcription mutant comprises bacteriophage RNA polymerase, deaminase and a first connecting sequence, and the deaminase is connected with the N end of the bacteriophage RNA polymerase through the first connecting sequence. Leakage expression can be reduced by increasing the number of regulatory elements in the inducible promoter, and controllable mutation is achieved; in addition, the negative screening gene sacB is added in the plasmid containing the orthogonal transcription mutants, the mutation plasmid can be rapidly removed after mutation is realized by adding cane sugar in a culture medium, and continuous mutation of the target gene is avoided. According to the directed evolution system and method, mutation can be rapidly and efficiently generated for a specific target gene, meanwhile, the mutation rate can be accurately regulated and controlled, leakage mutation is reduced, plasmid loss is rapidly achieved, and therefore the protein engineering modification speed is increased, and time and cost are saved.

The purpose of this invention is to provide a method for detecting mutant genes that can comprehensively and without omission measure the mutation rate of genes while suppressing costs. The method for detecting mutant genes of this invention involves performing a base extension reaction using a first pigment group and a second pigment group, respectively. The first pigment group is configured such that one of the bases A and B is not fluorescently labeled, while the other is fluorescently labeled, and GC is fluorescently labeled. The second pigment group is configured such that one of the bases C is not fluorescently labeled, while the other is fluorescently labeled, and AT is fluorescently labeled. Both the first and second pigment groups are configured such that the base extension reaction does not stop at the unlabeled bases but stops at the fluorescently labeled bases (see Figure 6).

The application discloses a DNA polymerase III mutant and application thereof. The mutant contains an amino acid sequence shown in SEQ ID No. 1, and the mutant can be applied to improving the mutation frequency of a host strain genome. In the application, the Escherichia coli is used as a starting strain, a high-efficiency evolution auxiliary plasmid is introduced, and the mutation frequency of the host is improved; combined with competitive pressure directional screening of a tryptophan structural analog 5MT, finally, the Escherichia coli engineering strain with high yield of tryptophan is obtained. The auxiliary plasmid comprises a pBad24 plasmid vector skeleton and an engineered Escherichia coli DNA polymerase III danQ nucleotide fragment. The high-efficiency evolution auxiliary plasmid provided by the application can significantly improve the mutation rate of the host genome, combined with the directional screening of 5MT, the traditional mutagenesis cycle can be greatly shortened, the engineering strain with high yield of tryptophan can be efficiently screened, and the application has important application value.

The invention relates to a base editing system based on I-E type Cas3 and application of the base editing system in saccharomyces cerevisiae gene editing, and belongs to the technical field of gene editing. An I-E type CRISPR system which is wide in editing window and high in mutation rate is developed in saccharomyces cerevisiae, error-prone DNA polymerase from different sources is selected to be fused with Cas3, the error-prone DNA polymerase is fused at the N end of the Cas3, and a fusion body with the highest mutation activity, namely the fusion body of the error-prone DNA polymerase PO1I5M and the Cas3, is obtained through screening. According to the invention, the operable range of the base editor on the saccharomyces cerevisiae genome is widened, multi-site base editing can be realized, and the editing window is wide.

The purpose of the present disclosure is to provide a technique capable of detecting a mutant gene and a mutation rate with high accuracy using capillary electrophoresis. This mutant gene detection method classifies signal peaks of a detection signal into a first group that is less than a first threshold value and a second group other than the first group, and increases an injection voltage until the signal peaks belonging to the first group are equal to or greater than the first threshold value. The injection voltage is reduced until the signal peak belonging to the second group is equal to or less than a second threshold value greater than the first threshold value (referring to FIG. 7).

The invention provides a method for constructing a multi-copy eukaryotic expression vector based on a programmable enzyme Argonaute and application of the multi-copy eukaryotic expression vector based on the programmable enzyme Argonaute, and belongs to the technical field of biological medicines.The method comprises the following operation steps that DNA assembly is conducted on recombinant plasmids In-pc-CDs based on Argonaute and resistance gene reconstruction, and expression units in the plasmids obtained through assembly are transferred to plasmids Lamp; in R-Arm, the multi-copy expression vector is obtained. A set of in-vitro seamless DNA assembly technology which is low in mutation rate, convenient to operate, easy to screen, short in assembly period, wide in base sequence universality and low in both economic cost and time cost is developed by starting from a novel programmable enzyme Argonaute and combining a resistance reconstruction strategy, and the in-vitro seamless DNA assembly technology is used as an eukaryotic expression platform DNA assembly tool to realize the in-vitro seamless DNA assembly of the eukaryotic expression platform. The invention provides a method for rapidly constructing a multi-copy expression vector and a signal peptide expression plasmid library, so that the construction of the CHO stable transfection cell strain is realized.

The invention provides a temperature-resistant breeding method for a temperature-resistant strain capable of synchronously removing sulfur and nitrogen. The method comprises the following steps: performing susceptible state culture on the strain capable of removing sulfur and nitrogen to change the selectivity and permeability of bacterial cells to a mutagenic agent; then, diethyl sulfate is added, more diethyl sulfate is promoted to enter cells under the action of alternate ice bath and 45 DEG C heat shock, and mutagenesis is carried out on the sulfur and nitrogen removal strains; and inoculating the mutated bacterial liquid into an inorganic culture medium salt solution containing Mg < 2 + >, and repeatedly culturing in a dark environment at 45 DEG C to obtain the temperature-resistant mutant strain with fixed temperature-resistant mutant inheritable characters. The mutation rate of the strain obtained by the breeding method is greatly improved and can reach 24.5% at most, the sulfur removal rate at 45 DEG C can reach 87.8%, and the strain has excellent temperature tolerance and sulfur and nitrogen removal rate.

The application belongs to the technical field of aquatic organism breeding, and discloses a method for creating grass carp resistant to hemorrhagic disease by knocking out dhcr7 a gene and application thereof. dhcr7 The method utilizes CRISPR-Cas9 technology to generate an insertion / deletion mutation in a grass carp dhcr7 gene, so that the gene cannot encode a protein or the encoded protein does not have a function. dhcr7 The application first knocks out the innate immune negative regulation gene dhcr7 in grass carp, obtains a F0 generation population with a high mutation rate, and finds that knocking out significantly improves the resistance of grass carp to GCRV-II virus, thereby providing a method and breeding material for breeding grass carp resistant to hemorrhagic disease and having important industrial application value.