137 results about "Resistant mutants" patented technology

This invention relates to inhibitors of NTRK that are active against wild-type NTRK and its resistant mutants.

This invention relates to inhibitors of NTRK that are active against wild-type NTRK and its resistant mutants.

The invention relates to an acid and high temperature resistant alpha-amylase, and its gene, engineering bacterium and preparation method. A technical proposal of the method consists of: utilizing a recombinant DNA technology for site-directed mutagenesis of a high temperature resistant alpha-amylase gene of Bacillus licheniformis, thus obtaining an acid resistant mutant gene of the high temperature resistant alpha-amylase, i.e. an acid and high temperature resistant alpha-amylase gene, and making use of a Bacillus subtilis expression system for secreting expression of the acid and high temperature resistant alpha-amylase. The acid and high temperature resistant alpha-amylase provided in the invention solves the problem of limited application of current high temperature resistant alpha-amylase due to its poor acid resistance and absence of high temperature resistance and acid resistance at the same time, satisfies some requirements for conducting a starch raw material liquefaction process under an acid and high temperature environment, and can improve product yield and quality as well as simplify the process.

Co-administration of a lysostaphin or other anti-staphylococcal agent which cleaves cross-links of peptidoglycans of staphylococci cell walls such as lysostaphin and an antibiotic effective against staphylococci due to antibiotic activity mediated by cell-wall activity is effective against staphylococcal infection, even staphylococci that may be resistant to one or other of lysostaphin or the cell-wall active antibiotic. Co-administration simultaneously suppresses the generation of antibiotic-resistant mutant strains. Effective cell-wall active antibiotics include β-lactams and glycopeptides.

The present invention disclosed a class of pyrimidine or pyridine compounds, pharmaceutically acceptable salts, stereoisomers, prodrugs and solvates thereof, preparation method therefor and pharmaceutical compositions and pharmaceutical uses thereof. The compounds can inhibit the variants of EGFR (Epidermis Growth Factor Receptor) proteinases, and therefore can inhibit the growth of a variety of tumor cells effectively. The compounds can be used to prepare antitumor drugs, used for the treatment, combined therapy or prevention of various different cancers. The compounds can overcome the drug resistance induced by the existing first-generation EGFR inhibitors such as gefitinib, erlotinib and so on. Particularly, the compounds can be used to prepare drugs for treating or preventing diseases, disturbances, disorders or conditions mediated by epidermis growth factor receptor variants (such as L858R activated mutants, Exon19 deletion activated mutants and T790M resistant mutants).

The invention belongs to the fields of biology and medicines and particularly relates to a method for detecting a resistant mutant of mycoplasma pneumoniae. By adopting Real-time PCR (Polymerase Chain Reaction) and a cycling probe technology for distinguishing the difference of monobases and searching a specific primer aiming at the mycoplasma pneumoniae in an upstream and a downstream sequence of 2063 bit/2064 bit of the mycoplasma pneumoniae 23SrRNA gene, specific cycling probes aiming at mutation-free sensitive strains, 2063-bit mutant drug-resistant strains and 2064-bit mutant drug-resistant strains can be respectively designed according to the difference of the bases at the 2063 bit/2064 bit of the mutation-free sensitive strains and mutant drug-resistant 23SrRNA gene of the mycoplasma pneumoniae; the PCR amplification can be carried out by using the specific primer of the mycoplasma pneumoniae; and the fluorescence intensity change can be read by a Real-time PCR thermal cycler in real time to determine the mutant types of samples to be detected. The invention can correctly distinguish the mutation-free sensitive strains from the mutant drug-resistant strains of clinical separation strains of the mycoplasma pneumoniae. The specificity is 100 percent and the sensitivity can reach 102copy/PCR reaction.

The invention provides a herbicide-resistant rape directive breeding method based on acetolactate synthase (ALS) target esterase, which belongs to a plant trait breeding method. The method comprises the following steps of selecting materials needed by production of rape or breeding of the rape, processing seeds with ethylmethane sulfonate (EMS), mutagenizing the seeds to be isolated and propagated to a M2 generation, and directionally screening herbicide-resistant mutant characters in a large group under the selection pressure of the herbicide adopting the ALS as the target esterase. In order to increase the probability for acquiring the mutant characters, the directive screening can be continuously conducted in multiple years, or conducted in multiple places in the same year or conducted in multiple places in multiple years until the needed mutant material is screened out.

The invention discloses a screening method for heavy metal cadmium adsorption mutants of Chlamydomonas reinhardtii. The screening method comprises: selecting a suitable screening concentration for heavy metal cadmium adsorption mutants according to the influence of different cadmium chloride concentrations on the growth of Chlamydomonas reinhardtii; Transformation to obtain Chlamydomonas reinhardtii mutants; screening out heavy metal cadmium adsorption mutants of Chlamydomonas reinhardtii, the screening of heavy metal cadmium adsorption mutants of Chlamydomonas reinhardtii includes screening heavy metal cadmium sensitive mutants and screening heavy metal cadmium resistant mutants; identification screening Mutant genes of heavy metal cadmium adsorption mutants of Chlamydomonas reinhardtii. The invention achieves the technical effect of being able to obtain a large amount of Chlamydomonas heavy metal cadmium adsorption mutants simply and efficiently.

A method for screening the salt-resistant mutant of sweet potato includes such steps as secondary culture of suspended embryonic cells of sweet potato, irradiating them by Co gamma-ray, sequentially culturing in liquid culture media A, B and C, culturing in solid culture medium A to obtain calli, sequentially culturing in solid culture media B, C and D to obtain plantlet, culturing in basic MS culture medium, culturing in liquid culture medium D, and culturing in Hoagland solution containing NaCl.

The invention discloses a pyrimidine compound, a pharmaceutically-acceptable salt, a stereoisomer, a prodrug and a solvate thereof, as well as a preparation method, a pharmaceutical composition and medical application of the pyrimidine compound. This type of compound can generate an inhibitory effect on variant forms of EGFR (epidermal growth factor receptor) protease, so that the compound can effectively inhibit the growth of various tumor cells, can be used for preparing antitumor drugs, can be applied to treatment, combined treatment or prevention of many different cancers, and can overcome drug tolerance induced by first-generation EGFR inhibitors including existing drugs of gefitinib, erlotinib and the like. More particularly, this type of compound can be used for preparing medicines for treating or preventing diseases, obstacles, disorders or illness states mediated by certain epidermal growth-factor receptors with variant forms (for example, L858R active mutants, Exon19 deletion active mutants, and T790M resistant mutants).

The invention discloses an herbicide resistance mutant and an application thereof, belongs to the field of plant biotechnology and relates to a protein nucleic acid mutant sequence capable of producing herbicide resistance in plants and a use of the herbicide resistance mutant in plant breeding. Through the clethodim herbicide, six mutants with ACCase inhibitor herbicide resistance are found in the rice mutant library. The resistance mutants can resist ACCase inhibitor herbicide such as clethodim. The invention discloses a use of a protein having ACCase inhibitor herbicide resistance and a gene encoding the same in transgenic or non-transgenic plant breeding. The herbicide resistance gene and protein can be used for breeding plants having herbicide resistance and especially for breeding grass crops such as rice, corn, wheat, barley, sorghum, millet, foxtail millet, etc., and have a great application value in plant breeding and agricultural production.

Disclosed are peptide nucleic acid (PNA) probes to detect lamivudine resistant mutants of hepatitis B virus (HBV), which causes acute and chronic hepatitis, kits for detecting lamivudine resistant HBV comprising the PNA probes, and methods for detecting lamivudine resistant HBV by using the kits. They can accurately detect mutations of rtL180M, rtM204V, rtM204I and rtV2071 within B and C domains of HBV DNA polymerase gene, the main cause of lamivudine resistance, as well as mixed mutants of more than one mutant. They can detect lamivudine resistant HBV with high specificity and sensitivity.

The invention discloses an O-type foot and mouth disease virus acid-resistant mutant strain, a capsid protein carried by the O-type foot and mouth disease virus acid-resistant mutant strain and a coding gene of the capsid protein and also discloses a key amino acid site for determining O-type foot and mouth disease virus acid-resistant characteristics and a use of the key amino acid site. An O-type foot and mouth disease virus parent strain is subjected to serial passage screening under acid stress so that a mutant strain having strong acid resistance is obtained, and an analysis result shows that a VP1 N17D mutational site is a key amino acid site for determining O-type foot and mouth disease virus acid-resistant characteristics, the O-type foot and mouth disease virus only with the VP1 N17D mutational site has the acid resistance the same as that of the mutant strain and also has a good replication capability and immunogenicity. The key amino acid site for determining O-type foot and mouth disease virus acid-resistant characteristics can be used for reconstruction of acid resistance of a foot and mouth disease virus vaccine and for exploitation of a novel foot and mouth disease gene engineering vaccine. The acid-resistant mutant strain rN17D can be used as a high-quality inactivated vaccine-production parent strain, can improve content of a 146S effective antigen in the inactivated vaccine and can improve vaccine immune efficacy.

The invention discloses a breeding method for resistant super-male polyploidy asparagus based on flow cytometry. The method comprises the following steps: (1) choosing excellent male plants in a field and carrying out indoor planting and microscopic examination; (2) mechanically separating microspores; (3) carrying out flow sorting; (4) carrying out suspension culture; (5) screening resistant mutants; (6) carrying out artificial doubling; (7) carrying out flow analysis; (8) subjecting the microspores obtained in step (7) respectively to field selective matching and cross combination and to in vitro rapid propagation; and (9) carrying out variety comparative tests on plants obtained after field selective matching and cross combination and plants obtained after in vitro rapid propagation, and applying plants obtained in the tests in production in the field. The method provided by the invention has the following beneficial effects: (1) a breeding period is shorter, breeding efficiency is higher, and operation is simpler; (2) an obtained variety has comprehensiveness; and (3) a breeding technology is novel.

A method for producing mutant of hemerocallis middendorffii by in vitro mutagenesis of ethyl methane sulfonate (EMS) amis to provide an EMS in vitro mutagenesis method for breed improvement of hemerocallis and creation of new germplasm resources and to obtain a target variant strain. The method for producing the mutant of the hemerocallis middendorffii by the in vitro mutagenesis of the ethyl methane sulfonate adopts the 1 to 2cm flower buds in normal growth and development state of the hemerocallis middendorffii as materials, inoculates callus induced by taking ovaries as explants to a differential medium, and green buds are differentiated. After the callus with buds is subjected to differentiation culture for 10 days, a callus block is treated with EMS semi-lethal dose at a concentration of 0.75-1.0 percent (w/v). The treated callus is inoculated to the differentiation medium for differentiation culture to obtain regenerated plants. When the regenerated plants grow to 1 to 2 cm high, the regenerated plants are cut down from the callus and put in a subculture medium to conduct subculture for 15 days, hemerocallis septoria tritici toxin semi-lethal dose at a concentration of 40 percent (v/v) is taken as directional selection pressure for stress screening, and disease-resistant mutant plants are obtained.

The invention discloses a polysubstituted quinazoline compound and an application thereof, and belongs to the field of chemical medicines. The substituted quinazoline compound represented by the general formula (I) and the pharmaceutically acceptable salt thereof have excellent brain barrier permeability, enhanced metabolic stability and longer metabolic half-life period, show higher inhibitory activity on an activated or drug-resistant mutant form EGFR than a wild type EGFR, and can effectively reduce side effects.

The present invention relates to certain 2-(2,4,5-substituted-anilino)pyrimidine compounds and pharmaceutically acceptable salts thereof which may be useful in the treatment or prevention of a disease or medical condition mediated through certain mutated forms of epidermal growth factor receptor (for example the L858R activating mutant, the Exon19 deletion activating mutant and the T790M resistance mutant). Such compounds and salts thereof may be useful in the treatment or prevention of a number of different cancers. The invention also relates to pharmaceutical compositions comprising said compounds and salts thereof, especially useful polymorphic forms of these compounds and salts, intermediates useful in the manufacture of said compounds and to methods of treatment of diseases mediated by various different forms of EGFR using said compounds and salts thereof.

The invention relates to a halogenated salicylanilide selected from closantel, rafoxanide, oxyclozanide and niclosamide and derivatives thereof including salts, hydrates, esters and the like for use in the topical treatment or prevention of infections caused by Gram-positive bacteria such as Staphylococcus, in particular Staphylococcus aureus, and Streptococcus, in particular Streptococcus pyogenes. Gram positive bacteria treated with the halogenated salicylanilides exhibit a very low frequency of appearance of resistant mutants compared to commonly used topical antibiotics.

Disclosed is a method for identifying an essential gene which serves as an antibiotic target in a bacterium, the method comprising the steps of:

• • (a) generating an antibiotic resistant mutant of said bacterium by a method comprising the step of selecting for growth in the presence of said antibiotic to produce an antibiotic resistant mutant clone (Ab^R mutant);
  • (b) transforming the Ab^R mutant with: (i) one or more essential genes of said bacterium; and (ii) a transposon which insertionally inactivates bacterial DNA, to produce a pool of transposon mutants which are merodiploid for said one or more essential genes;
  • (c) growing bacteria from the merodiploid pool in the presence of different amounts of said antibiotic to produce two or more test cultures; and
  • (d) comparing the distribution of transposon insertions between test cultures to identify a putative essential gene serving as a target of said antibiotic in said bacterium.

The invention provides a mutant XYNH of an extreme heat-resistant xylanase 1VBR. The mutant XYNH is prepared through mutation of phenylalanine at the 290th of an amino acid sequence of the xylanase 1VBR into histidine and has an amino acid sequence shown in the formula of SEQ ID NO.1. The invention also provides a gene for encoding the mutant XYNH. The gene has a nucleotide sequence shown in the formula of SEQ ID NO.2. The invention also provides a recombinant expression vector pPIC9K-XYNH with the gene for encoding the mutant XYNH and a recombinant strain with the recombinant expression vector. After the amino acid sequence of the xylanase 1VBR is subjected to site-directed mutagenesis, the high heat-resistant mutant XYNH is obtained, is highly expressed in a pichia pastoris expression system and has a wide application prospect in the fields of feed additives, health foods, papermaking, washing, brewing, textiles and pharmacy.

The present invention relates to certain 2-(2,4,5-substituted-anilino)pyrimidine compounds and pharmaceutically acceptable salts thereof which may be useful in the treatment or prevention of a disease or medical condition mediated through certain mutated forms of epidermal growth factor receptor (for example the L858R activating mutant, the Exon19 deletion activating mutant and the T790M resistance mutant). Such compounds and salts thereof may be useful in the treatment or prevention of a number of different cancers. The invention also relates to pharmaceutical compositions comprising said compounds and salts thereof, especially useful polymorphic forms of these compounds and salts, intermediates useful in the manufacture of said compounds and to methods of treatment of diseases mediated by various different forms of EGFR using said compounds and salts thereof.

The invention relates to a screening method for inducing successive cropping obstacle resistant mutants of strawberry with the mixed liquor of oxysporum toxin and autotoxin p-hydroxybenzoic acid as selection pressure and belongs to the agricultural biological technical field. The strawberry blight caused by fusarium oxysporum and the root system autotoxin p-hydroxybenzoic acid are important factors causing serious successive cropping obstacle of strawberry. The screening method employs seedling leaf sections of a strawberry group as the induction materials; and in the optimal callus induction medium (MS solid culture medium, maltose (10-30 g/L), TDZ (1-4 mg/L) and AgNO3 1mg/L) containing the mixed liquor of the toxin and p-hydroxybenzoic acid in the medial lethal concentration (10% of toxin+1.0*10-4 mol L-1), three resistant mutants high in differentiation rate, good in hereditary stability and high in firmness are selected. The screening method provides new technical way and theoretical support for realizing breakthrough and innovation of resisting continuous cropping germplasm resources under the successive cropping condition of strawberry.

The invention relates to the technical field of gene detection equipment, in particular to a helicobacter pylori typing and drug-resistant mutant gene detection method and device. A lifting assembly is located above a base, a detection table is located above the lifting assembly, a heat preservation box is located above the detection table, a partition plate is located in a heat preservation box, a refrigeration assembly is located below the partition plate, and a detection box is located on the side edge of the heat preservation box. An object needing to be detected is placed above the partition plate in the heat preservation box, then the refrigeration assembly is started, the interior of the heat preservation box is refrigerated, then the lifting assembly is started, a worker holds a handle, a rotating rod drives a rotating shaft, the rotating shaft enables a gear to rotate clockwise on the side edge of a lead screw, the lead screw moves upwards in a sleeve, and the height of the detection table fixedly connected with the lead screw is adjusted, so that detection personnel can detect the detection table conveniently, and the detection effect is improved.