432 results about "Kanamycin" patented technology

The invention relates to a kanamycin A aptamer electrochemical sensor based on signal probe chain substitution reaction and production and application methods of the kanamycin A aptamer electrochemical sensor. SD-EAB consists of a sulfhydryl-modified capture probe (an aptamer or a short complementary chain) and a signal probe (a short complementary chain or an aptamer) which is complementary to and is hybridized with the capture probe and has an oxidation-reduction mark. When kanamycin A exists, the signal probe is substituted and released from the surface of an electrode, so as to result in decreasing of current, and a decrease value of current is proportional to a logarithm of the concentration of the kanamycin A. The signal transduction of the kanamycin A aptamer electrochemical sensor provided by the invention is only caused by affine competition among target molecules, the short complementary chain and the aptamer, and is not associated with a conformation state of the aptamer, so that the generality of the aptamer is greatly improved. The SD-EAB has the advantages of high sensitivity, good specificity, wide dynamic interval and strong anti-jamming capability, without additional reagents.

A colibacillus-corynebacterium inducible expression carrier pDXW-8 and a building method thereof belong to the technical field of genetic engineering. The inducible expression carrier pDXW-8 can be copied and stably exists in colibacillus and corynebacterium and comprises a tac promoter, a terminator rrnBT1T2, a resistance marker card kanamycin mark resistance gene, a negative regulation gene laclPE104 and a multi-cloning site, wherein the tac promoter plays a transcript promoting function in the colibacillus and the corynebacterium, the terminator rrnBT1T2 has a transcript stopping function, the resistance marker card kanamycin mark resistance gene is used for selecting transformants of the corynebacterium, the negative regulation gene is used for severely controlling expression of the tac promoter, and the multi-cloning site includes 11 signal limited incision enzyme sites. In the corynebacterium, the carrier is moderate in foreign protein expression, and is particularly adaptable to study on corynebacterium metabolic engineering.

The invention provides a strain of Mycobacterium sp.16F for efficiently degrading polycyclic aromatic hydrocarbon and benzene organic matters, which has a preservation number of CGMCC No.6367. The mycobacterium 16F can efficiently, safely and rapidly degrade polycyclic aromatic hydrocarbons and benzene organic matters, can grow and degrade by using fluorene, naphthalene, anthracene, acenaphthene, phenanthrene, pyrene and benzopyrene as the sole carbon source and energy in aerobic condition, and can utilize benzene, m-xylene, toluene, salicylic acid, catechol and other multiple aromatic organic matters. The mycobacterium 16F is sensitive to streptomycin, rifampin, tetracycline, kanamycins and other antibiotics, has good degradation effects to mixed polycyclic aromatic hydrocarbons in aging soils and monocyclic benzene organic matters in water bodies, can be used for restoring and purifying the water-soil environment combinedly polluted by aromatic hydrocarbon organic matters, is important for promoting sustainable development, and has a wide application prospect.

The invention discloses a colorimetric analysis method for detecting kanamycin based on aptamer-modified magnetic beads and gold nanoparticles to simulate enzyme activity, and belongs to the technical field of analytical chemistry. In the present invention, the gold nanoparticles synthesized by tyrosine reduction of chloroauric acid simulate the peroxidase-like activity inherent in the enzyme AuNPs, and the gold nanoparticles modified by kanamycin-specific aptamers modify their complementary single-stranded cDNA The capture of nanoparticles, and the displacement of gold nanoparticles by the combination of kanamycin and aptamer, the peroxidation-like peroxidation of gold nanoparticles AuNPs contained in the supernatant after magnetic separation is related to the concentration of kanamycin The enzyme activity catalyzes the color reaction between the substrate tetramethylbenzidine (TMB) and H2O2, realizes the visual detection of kanamycin, and uses the linear relationship between the absorption value at 450 nm and the concentration of kanamycin to realize the detection of kanamycin. Colorimetric quantitative analysis of kanamycin. This method has the advantages of high sensitivity and good specificity, and is suitable for the quantitative analysis of kanamycin residues in food samples such as honey.

The invention relates to a biosensor for testing kanamycin based on conformational changes of a target-induced nucleic acid aptamer. The biosensor is prepared by sequentially modifying an HAP2 layer, a Helper layer and a homogeneous reaction mixed solution onto an electrode. The biosensor has the advantages that the specificity recognition function of the nucleic acid aptamer is adopted, and the aptamer of kanamycin is utilized as a recognition substance for high specificity detection of kanamycin in a target; through utilization of nucleic acid tool enzymes, the target is recycled and a signal amplification function is achieved, so that the detection sensitivity can be improved.

A Bacillus strain characterized by (i): sensitivity for ampicillin, vancomycin, gentamicin, kanamycin, streptomycin, erythromycin, clindamycin, tetracycline and chloramphenicol; (ii) antimicrobial activity against E. coli and Clostridium perfringens; and (iii) a sporulation percentage of at least 80 when measured after 2 days of incubation. The invention further relates to a method for selecting such strains. Many of the identified strains according to the invention are of the species Bacillus amyloliquefaciens. Some of the Bacillus amyloliquefaciens were further identified as Bacillus amyloliquefaciens subsp. amyloliquefaciens whereas others were identified as amyloliquefaciens subsp. plantarum. A Bacillus strain of the invention may be used as a feed additive to animal feed where it has a probiotic effect.

The invention discloses a medical composite alginate dressing containing antibacterial drugs and a preparation method thereof. In parts by weight, the medical composite alginate dressing comprises the following components: 50-99.9 parts of alginate and 0.05-10 parts of antibacterial drugs, The antibacterial drug is selected from gentamicin or its salt, neomycin or its salt, amikacin or its salt, fusidic acid or its salt, kanamycin or its salt, polycresol , mupirocin, sulfamethonium or its salt and clindamycin or its salt at least one. The medical composite alginate dressing of the present invention has strong ability to absorb exudate, has good water vapor transmission rate, can be biodegraded and has good biocompatibility, does not adhere to the wound and can quickly form gel after absorbing wound exudate , has strong moisturizing properties, can effectively promote wound healing, shorten wound repair time, can effectively prevent or treat sensitive bacterial infections, and can be widely used in acute and chronic wounds with exudate.

The invention discloses a preparation method and an application of a sensor for simultaneously detecting four aminoglycoside antibiotics and belongs to the technical field of novel function materials and biosensor analysis. According to the invention, a reference electrode is printed by the use of a silver paste and four working electrodes and a counter electrode are printed by the use of a conductive carbon paste on a rectangular substrate surface coated with a layer of a polyester film. Thus, a four-channel screen-printed electrode is prepared. The preparation method is characterized in that antibodies of four aminoglycoside antibiotics including streptomycin, gentamycin, kanamycins and spectinomycin are respectively fixed on surfaces of the four working electrodes by the use of a Pt nanoparticle-sulfated graphene-carboxymethyl chitosan conductive composite nano-material; and after the detection liquids are dripped, the four working electrodes are connected with a multichannel electrochemical workstation detection circuit so as to realize simultaneous detection of the four aminoglycoside antibiotics. The sensor provided by the invention is simple to prepare and convenient to process, requires low cost, and is convenient to carry. The detection method is simple and rapid and has high sensitivity and good specificity.

The invention relates to the technical field of the biosensor and in particular to a biosensor for detecting kanamycin based on nucleic acid aptamer comformational change induced by a target object. The specific preparation method comprises the following steps: pre-processing an electrode; decorating an HAP2 layer on the surface of the electrode; and decorating homogeneous reaction mixed liquid on the surface of the electrode. The biosensor is capable of using the specific recognition of the nucleic acid aptamer, using the aptamer of the kanamycin as a recognition substance for high specific detection of the target object kanamycin, using nucleic acid tool enzyme, and realizing the cyclic utilization of the target object, and has the function of amplifying the signal.

The present invention belongs to the field of plant transgene technology, and is especially agrobacterium mediating method of cultivating transgenic plant of sycamore as one garden tree. The agrobacterium mediating method includes the steps of genetic transformation, PCR detection and Southern hybridization detection, and features that through agrobacterium mediation to transduce GUS reporter gene to acceptor sycamore, adding kanamycin as selecting agent to the basic culture medium, screening the transformed acceptor cell, PCR detection, GUS gene detection, Southern hybridization and other steps, transgenic plant of sycamore is obtained. The present invention provides technological platform for the genetic improvement of tree, especially sycamore.

The invention discloses a method for efficiently preparing (S)-styrene glycol from a carbonyl reductase recombinant bacterium, belonging to the technical field of biocatalysis asymmetric conversion. The invention provides a novel Candidaparapsiospis carbonyl group reductase gene scr II with Genbank sequence number of GQ411433; the scr II is inserted into a vector pET28a to construct a recombinant plasmid pETSCR II which is converted into E.coli BL21(DE3) competent cell; and a recombinant bacterium E.coli BL21/pETSCR II with the preservation number of CCTCC NO:M209290 can be obtained by the screening of an LB flat plate containing 100 micrograms/ml kanamycin. The (S)-styrene glycol can be prepared by catalyzing 5g/L 2-carbonyl acetophenone obtained by asymmetrically reducing the recombinant bacterium; and the optical purity of products is 100 percent and the yield reaches 98.1 percent. The invention provides a novel functional gene and an effective path for efficiently preparing the (S)-styrene glycol.

The invention discloses a multi-residue colloidal-gold rapid detection kit and a detection method and application thereof, belonging to the field of immunology. The kit provided by the invention mainly comprises a multi-residue colloidal-gold rapid detection card; the detection card comprises a detector bar and a plastic card shell, and the detector bar is composed of a sample pad, a colloidal-gold antibody binding pad, a nitrocellulose membrane and a water absorbing pad. The colloidal-gold antibody binding pad comprises a colloidal gold labeled gentamycin monoclonal antibody, a colloidal gold labeled kanamycin monoclonal antibody and a colloidal gold labeled fluoroquinolone monoclonal antibody. The central part of the nitrocellulose membrane is coated with a detection line and a control line, wherein the detection line is arranged to be a protein conjugate and the control line is a goat anti-mouse IgG monoclonal antibody. The rapid detection kit provided by the invention can realize simultaneous detection of a plurality of residues only through simple pre-treatment, the whole operation process is simple, the kit is convenient to carry, result determination is rapid and accurate, and the kit is applicable to on-site monitoring and to qualitative screening of considerable samples.

The invention relates to an Agrobacterium rhizogenes-mediated transgene Stevia rebaudiana genetic transformation method. The method comprises: pre-cultured Stevia rebaudiana stem apex explant is immersed into an Agrobacterium rhizogenes solution of pRI101-ANDNA plasmid carrying target gene, treatments such as infection, co-culture and sterilization are performed, the hairy root is cultured in a kanamycin-containing screening culture medium, the anti-kanamycin hairy root is formed on the explant through induction, the hairy root is induced to form callus, differentiation of adventitious bud is performed, the adventitious bud continuously grows to form the test-tube plantlet, and a PCR amplification method is adopted to identify the transgene plant carrying out the target gene. With the technical scheme, the target gene can be transformed into the Agrobacterium rhizogenes, such that the steps of separation from the protoplast and culture are eliminated compared with genetic transformation of polyethylene glycol and other chemical methods; and compared with genetic transformation of gene gun and other physical methods, the method of the present invention has characteristics of no requirement of expensive equipment, and simple operation technology.

The invention discloses a method for conservation in vitro of cassava germplasm resources with stability and high efficiency, characterized by sub-culturing an aseptic test-tube plantlet in a growth inhibition medium containing kanamycin having a certain concentration, wherein the formula comprises MS, 0.2mg/L NAA, 80mg/L Kana, 30g/L cane sugar and 9g/L agar, and the pH value is 5.8; under the condition of no pollution, the test-tube plantlet can grow normally and is conserved for more than 22-24 months which is 10-12 times the conservation time of the medium with no addition of growth inhibition substances, the test-tube plantlet growing in the growth inhibition medium has a developed root system, significantly shortened intemode, significantly increased stalk pitch number, obviously thickened stalk, and deeper green leaves, and especially the greenhouse transplanting survival rate reaches more than 90% which is 5-8 times that of the control groups.

The invention pertains to the technical field of bio-treatment of environmental pollutants, particularly relates to a bacterium for degrading o-nitrobenzaldehyde and the applications thereof in bio-treatment of waste water and remediation of soil environmental pollution. The degrading bacterium of o-nitrobenzaldehyde is the strain ND1 of Alcaligenes sp. The bacterium can degrade o-nitrobenzaldehyde with high efficiency under aerobic condition, and utilize albocarbon, p-nitrophenol, o-nitrophenol, ortho-aminophenol, toluene, p-dimethylaminobenzaldehyde, 2, 4-dinitrophenol, para hydroxy benzoic acid, diphenylamine, benzoic acid, xylene and a plurality of other aromatic compounds. The Alcaligenes sp.ND1 is sensitive to five common antibiotics of tetracycline, kanamycin, streptomycin, chloromycetin and ampicillin, thus providing safe guarantees in the application thereof in the bio-treatment of waste water and remediation of soil environmental pollution.

The invention belongs to the technical field of environmental monitoring, and provides an immobilized enzyme method for improving the stability of horseradish peroxidase and application. At normal temperature and normal pressure, by using a co-precipitation method, a biological composite material of zeolite imidazolate skeleton-8/graphene immobilized natural horseradish peroxidase is synthesized in an aqueous phase. Embedding of the ZIF-8/GO composite material retains the excellent peroxidase catalytic activity of HRP, and meanwhile, the stability of the HRP is enhanced. Compared with a singleZIF-8 mineralized HRP material, the introduction of GO increases the tolerance of the HRP against complex environments such as high temperature, organic solvents and denaturants, and meanwhile, the storage stability and recycling capability of the HRP are enhanced. The peroxidase catalytic activity of the HRP@ZIF-8/GO biological composite material is regulated by utilizing DNA molecules; a non-marked colorimetric sensing method is established, and specific detection of kanamycin is realized.

The invention relates to a recombinant bacillus subtilis for expressing cellobiose-2-epimerase based on a D-alanine defective screening marker, as well as a construction method and an application of the recombinant bacillus subtilis, belonging to the technical field of genetic engineering of enzyme. According to the invention, bacillus subtilis 1A751 is taken as an original strain, D-alanine racemase genes (dal) on the chromosome of the bacillus subtilis 1A751 strain are knocked out, so that D-alanine defective bacillus subtilis 1A751 (dal<->) is obtained; by taking cellobiose-2-epimerase (CE enzyme) from thermoanaerobacter tengcongensis as a parent, fusing a P43 promoter on the upstream of the parent to establish P43-TsCE, establishing P43-TsCE to plasmid pUB110 to obtain pUB-P43-TsCE, and replacing antibiotics resistance genes kanamycin and bleomycin on the plasmid pUB-P43-TsCE with (dal), so as to construct pUB-P43-TsCE-dal; and transforming pUB-P43-TsCE-dal into host 1A751 (dal<->), and thus obtaining the recombinant bacillus subtilis for expressing cellobiose-2-epimerase, wherein the preservation number is CCTCC NO: M 2015582. The total enzyme activity of fermentation liquor reaches 7U/mL, and thus the recombinant bacillus subtilis has an important industrial application value.

The invention provides a method for detecting kanamycin. The kanamycin is detected by using double restriction enzyme cleavage sites and color change caused by G-tetrad. The preparation method specifically comprises the following steps: carrying out specific binding on a hair pin and kanamycin; adding a color developing agent into a homogeneous phase reaction mixed liquor for display detection. According to the method, high specific detection for the target object kanamycin is realized by using the oxidability of the G-tetrad; the effect of signal amplification is reached by using nucleic acid tool enzymes.

The invention discloses a method for detecting residual kanamycin and application thereof, and belongs to the technical field of analysis chemistry, wherein the detection method is based on aptamer initiated cyclic enzyme digestion of exonuclease III (Exo III). According the method, mercapto self-assembly is utilized, single stranded DNA (ssDNA) that is complementary with kanamycin aptamer (K-aptamer) is grafted on the surface of a gold electrode, then a little amount of K-aptamer is added, and the K-aptamer is matched with ssDNA to form a little amount of double stranded DNA (dsDNA). Then Exo III is added, the ssDNA in dsDNA can be specifically digested by Exo III, thus the residual aptamers are released, the released aptamers can combine with ssDNA to form dsDNA, another enzyme digestion is triggered then, and after several circulations, the modified ssDNA is completely digested by enzymes. Kanamycin exists in the system, through the combination between kanamycin and aptamers, the circulation enzyme digestion is inhibited, thus ssDNA is preserved, and the amount of preserved ssDNA is related with the concentration of kanamycin. An electro-analysis method is used to absorb electrical signal molecules namely hexaammine ruthenium (RuHeX) through static electricity absorption so as to quantitatively detect residual kanamycin; and the method has high sensitivity and can sensitively detect residual kanamycin in milk.

The invention discloses a synthesis method of amikacin. The synthesis method comprises following steps: firstly, a partially silanization protection product of kanamycin A is prepared; dehydration of the partially silanization protection product with PHBA under the action of DCC is carried out so as to obtain a acylated product; the acylated product is subjected to hydrolysis, nitrilase, and column chromatography purification so as to obtain amikacin. According to the synthesis method, NOP is not used, synthesis of an active ester via esterification is avoided, damage on the health of workers is reduced greatly, solid waste generated in production process is reduced greatly, product yield is increased, and the synthesis method is especially suitable for industrialized production.

The invention discloses a multimeric protein having the effect of brain targeting, and a preparation method and usage thereof. The method comprises the steps: firstly, expressing cholera toxin B subunit and a fusion protein EGFP-CTA2-TAT of three proteins: an enhanced green fluorescent protein, a cholera toxin A subunit and cell-penetrating peptide in escherichia coli by incompatible double plasmid systems to obtain CTB gene by PCR amplification; cloning the gene segment into a carrier pET-28a to obtain a recombinant plasmid pET-28a-CTB; using wild type CTA2, EGFP and TAT amino acid sequences as templates, inserting 3 enzyme cutting sites and linkers between EGFP and CTA2, and optimizing to obtain codons suitable for expression in escherichia coli; cloning the gene segment into a carrier PET-22b (+) to obtain recombinant plasmid PET-22b-EGFP-CTA2-TAT; using different resistances of PET-28a-CTB and PET-22b-EGFP-CTA2-TAT, and co-transforming the different resistances of the PET-28a-CTB and the PET-22b-EGFP-CTA2-TAT into escherichia coli BL21, to obtain engineering bacteria after screening under double resistance selection pressure of penbritin and kanamycin. CTB5/EGFP-CTA2-TAT chimeric proteins can be obtained after inducible expression of the engineering bacteria by IPTG. The invention further discloses the preparation method and usage of the protein.

The invention provides a method for specifically detecting kanamycin based on an electrochemical luminescence aptamer sensor, and particularly belongs to the field of electrochemical luminescence detection. The method comprises the steps of (1) loading silver nanoparticles on a composite material (HLPNs@Ag) of high-luminescence polydopamine nanospheres, and preparing black phosphorus quantum dots;(2) preparing an electrochemical luminescence aptamer sensor; and (3) jointly modifying the surface of a glassy carbon electrode by utilizing electrostatic adsorption combination between the HLPNs@Agand the black phosphorus quantum dots to improve the sensitivity and stability of electrochemical luminescence, and then loading the aptamer to obtain the electrochemical luminescence aptamer sensor.The sensor can specifically recognize kanamycin, the detection range is 1.0*10<-12>mol/L-1.0*10<-7>mol/L, and the lowest detection limit is 1.7*10<-13>mol/L. According to the invention, the kanamycindetection sensitivity is high, the specificity is strong, and the operation is simple.

The invention relates to the field of food safety detection, and in particular discloses a detection method for a kanamycin A enzyme-linked aptamer and an application of the kanamycin A enzyme-linked aptamer. By a streptavidin-biotin-aptamer mode, kanamycin A can be detected; furthermore, a detection condition is optimized; and finally a condition with the lowest detection limit is obtained and the condition is high in sensitivity and specificity. According to the method, the kanamycin A in milk, pork, chicken, pork liver and honey can be detected according to the specificity; and the method has a wide application prospect.

The invention provides a preparation method for an aptamer-molecular imprinting fluorescent sensor having double specific recognition on kanamycin. The method comprises the following steps: firstly, the template molecule kanamycin, a thiol modified kanamycin aptamer and methacrylic acid form a prepolymerized complex; secondly, the prepolymerized complex, a crosslinking agent, allylamine modified CdSe quantum dots, and an initiator form an aptamer-quantum dot complex; and finally, the template molecule kanamycin in the aptamer-quantum dot complex is eluted, and therefore the aptamer-molecular imprinting fluorescent sensor having double specific recognition on the kanamycin is obtained. The invention also provides the aptamer-molecular imprinting fluorescent sensor having double specific recognition on the kanamycin prepared by the above preparation method, and an application of the sensor in detecting the content of the kanamycin in a sample. The aptamer-molecular imprinting fluorescentsensor provided by the invention has double specific recognition on the kanamycin, and very good selectivity on the kanamycin.