15 results about "Double mutation" patented technology

The invention relates to the technical field of biology, in particular to a cis-trans typing method for drug-resistant gene mutation EGFR T790M / C797S. The invention provides an EGFR (Epidermal Growth Factor Receptor) T790M / C797S cis-trans typing method based on a locked nucleic acid LNA (Low Nucleic Acid) probe, ultrahigh-specificity DNA (Deoxyribose Nucleic Acid) polymerase and a primer probe combination. The typing method can be used for accurately distinguishing EGFR T790M / C797S double-mutation cis-configuration and trans-configuration; meanwhile, the kit has the advantages of high sensitivity, high specificity, simple steps and low cost, is suitable for detecting low-abundance samples such as circulating tumor DNA (ctDNA) and can meet the clinical rapid detection requirement.

According to the wireless network intelligent optimization deployment method and system disclosed by the invention, the network deployment strategy is issued to the edge node, so that the calculation amount of the integrated controller is reduced, and the optimization efficiency of the network deployment strategy is improved; besides, strategy chromosomes are evolved through a double-variation mechanism, and a dynamically changing gene mutation probability and an environment evolution range are introduced, so that the algorithm can quickly jump out of a local optimal solution, dynamically track and adapt to the change of a network environment, and the convergence speed of the evolutionary algorithm is remarkably improved; and finally, analyzing the strategy chromosome according to the network state data, and determining an optimized deployment strategy. According to the method, the overall overhead and delay of a network deployment strategy are remarkably reduced, and the efficiency is improved.

The invention relates to the field of enzyme engineering, and provides a BhrPETase variant capable of improving stability through site-specific replacement under the background of Bhr6M (SEQ ID NO: 1) and application of the BhrPETase variant, and the replacement is M57I and / or S184H, preferably double mutation M57I / S184H. The variant shows remarkable thermal stability and storage stability under a unified measurement caliber: the condition t1 / 2 at 90 DEG C is greater than or equal to 400 minutes, the condition t1 / 2 at 70 DEG C is greater than or equal to 7 days, and the residual activity after 30 days of storage at 30 DEG C is greater than or equal to 90%. The invention also discloses a nucleic acid encoding the variant, a vector, a recombinant host, an enzyme preparation, and a method for depolymerizing PET and a copolymer thereof in a process temperature range of 70-90 DEG C. Compared with a control Bhr6M, the variant maintains more lasting activity in high-temperature and long-period operation, is suitable for PET substrates with different forms and crystallinity, reduces the enzyme supplementing frequency and improves the stability of a device.

To provide a human interferon-beta mutant having a double mutation and a method for improving the safety of the human interferon-beta mutant.SOLUTION: Provided are a human interferon-beta variant comprising an amino acid sequence in which the 17th amino acid cysteine of human interferon-beta is substituted with serine and the 27th amino acid arginine is substituted with threonine, and a method for improving the stability of a human interferon-beta R27T variant, the method comprising the step of changing the 17th amino acid cysteine of a human interferon-beta R27T variant, in which the 27th amino acid arginine of human interferon-beta is substituted with threonine, to serine.SELECTED DRAWING: Figure 1

This invention discloses a method and system for intelligent optimization deployment of wireless networks. By distributing network deployment strategies to edge nodes, the computational load on the central controller is reduced, improving the optimization efficiency of network deployment strategies. Furthermore, by using a "double mutation mechanism" to evolve the strategy chromosome, dynamically changing gene mutation probabilities and environmental evolution ranges are introduced, enabling the algorithm to quickly escape local optima and dynamically track and adapt to changes in the network environment, significantly improving the convergence speed of the evolutionary algorithm. Finally, the strategy chromosome is analyzed based on network state data to determine the optimized deployment strategy. This invention significantly reduces the overall overhead and latency of network deployment strategies and improves efficiency.

The invention belongs to the technical field of green chemistry, and particularly relates to a method for modifying a flexible ring region of nitrile hydratase and application of the method. The specific method comprises the following steps: carrying out double mutation on nitrile hydratase sites alpha D38 and alpha I152, or carrying out double mutation on nitrile hydratase sites alpha E157 and beta G197, or carrying out quadruple mutation on the nitrile hydratase sites alpha D38, alpha I152, alpha E157 and beta G197, so as to construct the nitrile hydratase mutant with improved thermal stability. The thermal stability of the nitrile hydratase modified by mutation is greatly improved. The mutant nitrile hydratase can keep the conformation and activity for a longer time, the resistance to external thermal interference is enhanced, and the half-life period for catalyzing an adiponitrile reaction is remarkably prolonged, which is the inherent excellent attribute of the mutant nitrile hydratase as a catalyst, and the mutant nitrile hydratase has important reference significance for research on improvement of the thermal stability of the nitrile hydratase.

The present application relates to the technical field of bioengineering, and particularly relates to a polyphosphate kinase mutant with high catalytic activity and application thereof in synthesis of glutathione. The present application provides a polyphosphate kinase mutant with high catalytic activity, which is characterized in that the polyphosphate kinase mutant is mutated from an amino acid sequence shown in SEQ ID NO: 2 into one of the following: (1) single mutation is made to the 234th amino acid in the amino acid sequence shown in SEQ ID NO: 2; (2) double mutations are made to the 234th and 166th amino acids in the amino acid sequence shown in SEQ ID NO: 2; wherein a nucleotide sequence of a coding gene coding the amino acid sequence shown in SEQ ID NO: 2 is as shown in SEQ ID NO: 1. ch PPK-N234A and double-site mutation polyphosphate kinase mutant ch PPK-N234A / K166D has high activity, and the enzyme activity is increased by 4.19 times and 6.12 times, respectively, compared with wild-type polyphosphate kinase.

Provided in the present invention are a mutant of Burkholderia cepacia lipase, and a recombinant expression vector thereof and the use thereof. The mutant comprises P131S, T132A, T251A, T251S, P131A, P131Q, T132G, Q88S or P113A single mutation, Q88S and P113A double mutation, and combinations of multi-site mutations including combination 1 of Q88S, P113A, T132G and L287S, combination 2 of Q88S, P113A, P131S and L287S, and combination 3 of Q88S, P113A, P131S and T251A.

The invention discloses a leucine transporter mutant capable of reducing methionine transport activity and application of the leucine transporter mutant, and belongs to the technical field of bioengineering. Compared with a wild leucine transporter with an amino acid sequence as shown in SEQ ID NO.1, the mutant provided by the invention contains amino acid mutation at the 30th site, the 108th site or the 123th site, and the amino acid mutation is F30K, F30P, S108F, S108Y or L123R respectively. In order to improve the ACC transfer efficiency, the invention also provides double mutations of S108F / L160Y. Experiments show that compared with a wild type, the Escherichia coli strain of the leucine transporter mutant has the advantages that the sensitivity to methionine analogues is obviously improved, and the concentration of methionine in the strain can be obviously improved. Meanwhile, the double mutants can effectively improve the ACC tolerance of escherichia coli. Therefore, the method has a good application prospect in the field of ACC fermentation preparation.

The invention discloses a Sortase A transpeptidase mutant and application thereof in the technical field of bioengineering, the Sortase A transpeptidase mutant is obtained through single mutation or double mutation on the basis of a protein sequence shown in SEQ ID NO.2, the protein sequence shown in SEQ ID NO.2 is a truncated mutant at the 60th-206th site made on wild type Sortase A transpeptidase shown in SEQ ID NO.1, and the Sortase A transpeptidase mutant is obtained through single mutation or double mutation on the basis of the protein sequence shown in SEQ ID NO.2. The Sortase A transpeptidase mutant provided by the invention has higher yield, activity and thermal stability, and has wider application conditions. Besides, a cysteine is introduced to the C terminal of the Sortase A transpeptidase mutant protein, and the Sortase A transpeptidase mutant is fixed on the magnetic beads by utilizing the principle of sulfydryl covalent coupling, so that the application value of the Sortase A transpeptidase mutant in protein labeling is realized.

The application discloses preparation and application of ketopantoate hydroxymethyltransferase mutants for D-pantoic acid production and belongs to the technical field of genetic engineering and enzyme engineering. By means of genetic engineering and enzyme engineering, the application mutates ketopantoate hydroxymethyltransferase of Escherichia coli, expresses the obtained single mutation and double mutation in an improved chassis cell, and can significantly improve the D-pantoic acid yield of the Escherichia coli, thereby creating conditions for expanding industrial application.

The invention relates to an EGFR mutation inhibitor and application thereof. Particularly, the invention relates to an EGFR mutation inhibitor with a structure shown in a formula (I), a pharmaceutical composition of the EGFR mutation inhibitor, application of the EGFR mutation inhibitor as the EGFR mutation inhibitor and application of the EGFR mutation inhibitor in preparation of drugs for treating cancers, tumors or metastatic diseases which are at least partially related to EGFR Del19 mutation, EGFR L858R mutation, EGFR L858R / C797S double mutation, EGFR Del19 / C797S double mutation, L858R / T790M / C797S three mutation and Del19 / T790M / C797S three mutation, the invention particularly relates to application in preparation of drugs for treating hyperproliferative diseases and cell death disorder inducing diseases. Wherein the definition of each substituent in the formula (I) is the same as the definition in the specification.

The invention belongs to the technical field of green chemistry, and particularly relates to a method for modifying a flexible ring region of nitrile hydratase and application of the method. The specific method comprises the following steps: carrying out double mutation on nitrile hydratase sites alpha D38 and alpha I152, or carrying out double mutation on nitrile hydratase sites alpha E157 and beta G197, or carrying out quadruple mutation on the nitrile hydratase sites alpha D38, alpha I152, alpha E157 and beta G197, so as to construct the nitrile hydratase mutant with improved thermal stability. The thermal stability of the nitrile hydratase modified by mutation is greatly improved. The mutant nitrile hydratase can keep the conformation and activity for a longer time, the resistance to external thermal interference is enhanced, and the half-life period for catalyzing an adiponitrile reaction is remarkably prolonged, which is the inherent excellent attribute of the mutant nitrile hydratase as a catalyst, and the mutant nitrile hydratase has important reference significance for research on improvement of the thermal stability of the nitrile hydratase.

The application discloses an aldolase mutant and application thereof. The aldolase mutant is obtained by double mutation of F184Y and W199F on wild-type aldolase enzyme from Escherichia coli, and the amino acid sequence of the aldolase mutant is shown as SEQ ID No. 4. The specific activity of the aldolase mutant in catalyzing synthesis of (4R, 6S)-6-chloromethyl-2, 4-dihydroxy-2H-pyran is increased to nearly 4 times of that of the wild-type enzyme, and the substrate tolerance is also more superior.

This application relates to a drug lead compound with ALK G1202R / L1196M double mutation inhibitory activity, a virtual screening method, and its application. The method includes: obtaining resolved single-mutant complex structures from a database; constructing screening models based on the complex structures and performing standardized preprocessing on the crystal structures in each model; optimizing the structure and preparing the conformation of the compound library to be screened; determining the docking method, screening the optimal screening model, clustering the optimal screening model, docking it with the compound library to be screened, and obtaining drug lead compounds with ALK G1202R / L1196M double mutation inhibitory activity through drug-like property filtering, ligand structure clustering, and ADMET property prediction. The technical solution of this application can accurately screen ALK G1202R / L1196M double mutation inhibitory lead compounds, shortening the research and development cycle, reducing costs, and has clinical translational value.