42 results about "Purine nucleoside phosphorylase" patented technology

Purine N⁹-β-D-nucleosides containing 3-amino-3-deoxy-β-D-ribofaranose, 3-amino-2,3-dideoxy-β-D-ribofuranose, and 2-amino-2-deoxy-β-D-ribofuranose as sugar moieties are synthesized by biocatalytic transglycosylation of purine bases and the respective 3′-amino-3′-deoxyuridine, 3′-amino-3′-deoxythymidine and 2′-amino-2′-deoxyuridine as donors of the carbohydrate moiety, and the cells of Escherichia coli as a biocatalyst or glutaraldehyde (GA) treated cells of Escherichia coli as a biocatalyst or a mixture of thymidine (uridine) phosphorylase and purine nucleoside phosphorylase.

The invention relates to an adenosine deaminase detection kit. A vessel is contained in the detection kit and filled with liquid for detection, the liquid for detection is prepared from 50-100 mmol/L of glycine buffer solution, 50-80 mmol/L of sodium benzoate, 12/18 u/L of purine nucleoside phosphorylase, 30-40 u/L of xanthine oxidase, 200-300 u/L of peroxidase, 30-100 g/L of glyceraldehyde, 0.5 g/L of sodium azide, 10-200 mmol/L of disodium hydrogen phosphate, 100-300 mmol/L of KCl, 40-100 mmol/L of mannitol, 0.1-0.3 ml/L of preservative, 100-150 mmol/L of adenosine, 2-4 mmol/L of 4-aminoantipyrine, 10-15 mmol/L of color developing agent, 20-40 mmol/L of adenine nucleoside and 3-5 g/L of bovine serum albumin. The detection kit has the advantages of being high in determination precision, high in antijamming capacity, suitable for automated rapid determination and capable of creating favorable conditions for routine development of ADA detection application in clinic.

The invention provides an assay kit for adenosine deaminase. The assay kit comprises a reagent R1 and a reagent R2. The reagent R1 comprises TRIS, HCL, xanthine oxidase, purine nucleoside phosphorylase, 4-aminoantipyrine, peroxidase and sodium aspartate; and the reagent R2 comprises TRIS, HCL, adenosine, N-ethyl-N-(2-hydroxy-3-sulfopropyl)-3-methylaniline sodium slat and glycerol. The assay kit ofthe invention belongs to the technical field of biological detection, is simple in reagent composition, good in stability, rapid in reaction and low in cost, and can accurately detect adenosine deaminase; and the detection results of the assay kit have no obvious difference from the detection results of listed products.

The invention discloses a method for preparing ribavirin through genetically engineered bacteria and belongs to the technical field of genetic engineering. Particularly, the method comprises the stepsthat a pun gene segment with a nucleotide sequence shown in SEQ ID NO:1 is synthesized; a recombinant plasmid pET20b-BA-pun is established, and then the genetically engineered bacteria BL21/pET20b-BA-pun are established and induced so as to obtain a key enzyme, namely purine nucleoside phosphorylase, for synthesizing the ribavirin. The genetically engineered bacteria are used for synthesizing theribavirin, the conversion rate is high, the cost is low, and the method is environmentally friendly and has important significance in industrial production.

An adenosine deaminase assay kit consists of a reagent R1 and a reagent R2 which are independent from each other, wherein the reagent R1 comprises the following components: a buffer solution, a preservative, a protective agent, an anti-interference agent, a surfactant, a reaction enhancer, peroxidase, purine nucleoside phosphorylase, xanthine oxidase, 4-aminoantipyrine and water; and the reagent R2 comprises the following components: a buffer solution, a protective agent, a reaction enhancer, a preservative, adenosine, a chromogen substance and water. The adenosine deaminase assay kit is highin analysis sensitivity, good in repeatability and high in anti-interference capability, and the linearity can reach 300 U/L or above.

A method for producing cladribine (2-chloro-2′-deoxyadenosine) comprising the steps of:

a) reaction of 2-deoxyuridine with 2-chloroadenine, in the presence of uridine phosphorylase (UPase) and purine nucleoside phosphorylase (PNPase) in an aqueous reaction medium possibly containing up to 40% v/v of an aprotic dipolar solvent, to obtain cladribine dissolved in said reaction medium;

b) isolation of the cladribine by precipitation by means of concentration and alkalinisation of the reaction medium up to pH 11.5-12.5.

The invention belongs to the technical field of medicine and biochemistry and particularly relates to an adenosine deaminase detection kit. The kit comprises a reagent R1 and a reagent R2; the reagentR1 comprises purine nucleoside phosphorylase, xanthine oxidase, peroxidase, a preservative, 4-amino antipyrine and a buffer solution; the reagent R2 comprises adenosine, a color developing agent, a preservative and a buffer solution. The adenosine deaminase detection kit adopts a continuous monitoring method for detection, and the main wavelength is 550 nm; the detection kit has the advantages ofhigh sensitivity and accuracy and the like.

The invention discloses a kit for determining 5'-ribonuclease. The kit is composed of a reagent R1 and a reagent R2 which are independent of each other. The reagent R1 is prepared from the following components: a buffer solution, a preservative, a protective agent, an anti-interference agent, a surfactant, a reaction enhancer, peroxidase, purine nucleoside phosphorylase, xanthine oxidase, a chromogen substance and water; and the reagent R2 is prepared from the following components: a buffer solution, a protective agent, a reaction enhancer, a preservative, disodium inosinate, 4-aminoantipyrineand water. The kit is high in analysis sensitivity, good in repeatability and high in anti-interference capability, the linearity can reach up to 400U/L, the detection of abnormal specimen results conforms to the actual concentration, and the accuracy of normal specimen test results is not affected.

The invention relates to a method for synthesizing vidarabine by an enzymic method, and provides a method for preparing vidarabine by a two-step method. According to the method, different functions of uridine phosphorylase and purine nucleoside phosphorylase are utilized fully, so that reaction is carried in one direction; reverse reaction is eliminated; and conversion rate of the vidarabine is increased remarkably.

The invention discloses a method for measuring relative content of hypoxanthine riboside and adenosine in samples to be tested. The method includes converting hypoxanthine riboside in an adenosine sample into purple red quinone derivatives by an enzyme-coupled system composed of PNP (purine nucleoside phosphorylase), XTO (xanthine oxidase) and POD (peroxidase), and measuring solution absorbance value A1 under specific wavelength; measuring absorbance value A2 after adding buffer solution containing adenosine deaminase and keeping reaction for some time, and calculating relative content of hypoxanthine riboside and adenosine in adenosine substrate by the values A1 and A2. The method is green and environment friendly, relative content of hypoxanthine riboside and adenosine can be calculated without reference of calibrators, and detection can be realized by a common visible spectrophotometer. The method is high in flexibility, good in linearity and precision, accurate in results and convenient and quick to operate, and can be used for various types of analyzers to meet requirements of testing the samples in large scale.

The invention discloses an apolipoprotein E test kit, comprising a reagent R1 and a reagent R2. The reagent R1 comprises a glycine buffer solution, polyoxyethylene, sodium ethylene diamine tetracetate, purine nucleoside phosphorylase, dodecyl phenol, xanthine oxidase, sodium benzoate, glyceraldehyde, potassium dihydrogen phosphate. The reagent R2 comprises a glycine buffer, a latex particle of apolipoprotein E monoclonal antibody, nonidet p40, potassium chloride, calcium acetate, adenosine, disodium hydrogen phosphate, sodium ethylene diamine tetracetate, hypoxanthine nucleotide. The apolipoprotein E test kit can accurately measure in vitro, and is effectively applied to clinical auxiliary diagnosis and screenings for diseases such as hyperlipemia, coronary heart disease, hepatopathy, acute hepatitis, biliary cirrhosis, etc., and has excellent detecting stability and detecting accuracy.

The present invention relates to a 2'-deoxy-2'-fluoro-beta-D-arabinofuranosyladenine production method, and discloses mutations at a certain specific loci of the amino acid sequences of purine nucleoside phosphorylase (PNP) and pyrimidine nucleoside phosphorylase (PyNP), and a series of obtained mutants, wherein the transglycosylation activities of the mutants are extremely significantly improved.

The present invention provides engineered purine nucleoside phosphorylase (PNP) enzymes, polypeptides having PNP activity, and polynucleotides encoding these enzymes, as well as vectors and host cells comprising these polynucleotides and polypeptides. Methods for producing PNP enzymes are also provided. The present invention further provides compositions comprising the PNP enzymes and methods of using the engineered PNP enzymes. The present invention finds particular use in the production of pharmaceutical compounds.

A glyoxal-guanosine-group compound is prepared either by reacting glyoxal-guanine with any one of ribose-1-phosphate and 2-deoxyribose-1-phosphate in the presence of purine nucleoside phosphorylase, or by reacting glyoxal-guanine with any one selected from the group consisting of uridine, 2′-deoxyuridine and thymidine, together with phosphate ion, in the presence of purine nucleoside phosphorylase and pyrimidine nucleoside phosphorylase. The glyoxal-guanosine-group compound is then decomposed by alkali, whereby a guanosine-group compound consisting of guanosine and 2′-deoxyguanosine is prepared.

The invention is related to phosphorus substituted purine nucleoside phosphorylase inhibitory compounds, compositions containing such compounds, and therapeutic methods that include the administration of such compounds, as well as to processes and intermediates useful for preparing such compounds.

The invention relates to a method for determining the activity of adenosine deaminase, further to an adenosine deaminase detection kit, and belongs to the technical field of medical test determination. According to the method, adenosine used as a substrate is converted and dehydrogenated by using purine nucleoside phosphorylase and xanthine dehydrogenase as tool enzymes, oxidized coenzyme is reduced to form a reduced coenzyme, and the enzyme reaction rate is calculated by detecting the generation amount of the reduced coenzyme I at a wavelength of 340 nm. The method of the present invention has advantages of less reaction steps, less kinds of raw materials, good reagent stability, wide linear range, high sensitivity, good accuracy and convenient promotion.

The invention relates to primers, kit and method to detect transcriptional level of purine nucleotide phosphorylase PNP gene in macaque liver by RT-qPCR (real-time quantitative polymerase chain reaction), and belongs to the technical field of molecular biology. A template is made with cDNA synthesized by reverse transcription of total RNA extracted from fresh macaque liver tissue; a PCR primer combination is used to perform real-time fluorescent quantitative PCR amplification; Ct values of PNP gene fragments and reference gene GAPDH fragments, dissolution peaks, and amplification efficiency are attained; multiple-expressed delta delta C(t) value of the homogenize PNP gene is acquired by conventional treatment; relative expression value of the transcriptional level of PNP gene is acquired finally. An effective means to study PNP functionality of macaque and influence of relevant drugs upon PNP is provided; in addition, the primers, kit and method herein are applicable to real-time quantitative PCR detection and have the advantages of good operational simplicity, high repeatability, low detection cost, high sensitivity, high specificity and good convenience of popularization and application.