288 results about "Glycosyltransferase Gene" patented technology

Steviol glucosyltransferases and methods for producing steviol glycosides using the enzymes are provided.The present invention provides steviol glucosyltransferases and methods for producing steviol glycosides using the enzymes. The invention also provides transformants into which steviol glucosyltransferase genes are introduced and methods for preparing the transformants.

The invention relates to the clone and the expression of alpha-cyclodextrin glycosyltransferase (alpha-CGTase), which belong to the field of enzyme gene engineering and enzyme engineering. The cgt gene expression method comprises the following steps: obtaining cgt gene SEQ ID NO:1 from total DNA of Peanibacillus macerans JFB05-01; selecting plasmid pET20b(+) as the expression vector of cgt gene; and selecting E.coli BL21(DE3) as the expression host to achieve high-efficiency extracellular expression of the cgt gene, wherein the cgt gene has 2,061 nucleotides and 687 coded amino acids; prokaryotic expression plasmid is constructed; and alpha-CGTase is expressed by transformed E.coli. Recombinase has cyclization activity and can transform starch and relevant matrix into cyclodextrin. The recombined alpha-CGTase has an optimal temperature of 40 to 45 DEG C and an optimal pH value of 5.5, and has higher thermal stability below 40 DEG C and poor thermal stability above 50 DEG C. The alpha-CGTase meets the requirement for industrial application such as food and medicines, and can be used for industrial production of alpha-cyclodextrin and beta-cyclodextrin.

The present invention provides an enzyme which catalyzes a reaction to transfer sugar to a hydroxyl group at position 2′ of chalcones and a gene thereof, and preferably an enzyme which catalyzes a reaction to transfer glucose to a hydroxyl group at position 2′ of the chalcones. Furthermore, the invention provides a plant whose flower color has been changed using the glycosyltransferase. Using probes corresponding to conservative regions of the glycosyltransferase, some tens of glycosyltransferase genes having nucleotide sequences corresponding to the conservative regions were cloned from flower petal cDNA libraries of carnation and the like. Furthermore, each of the glycosyltransferase genes was expressed in Escherichia coli, activity to transfer glucose to position 2′ of the chalcone, i.e., the glycosyltransferase activity at position 2′ of chalcone was confirmed in an extract solution of the Escherichia coli, and it was confirmed that cloned genes encoded the glycosyltransferase at position 2′.

The invention discloses a tulip flavonoid 3-O-glucosyltransferase Tf3GT protein and a coding gene thereof. The protein is a protein composed of amino acid sequence disclosed as SEQ ID NO.2, or a protein with tulip flavonoid 3-O-glucosyltransferase activity obtained by substitution, deletion or addition of one or more amino acids on the basis of the amino acid sequence disclosed as SEQ ID NO.2. The invention also provides a nucleic acid sequence disclosed as SEQ ID NO.1 for coding the protein. When the tulip flavonoid 3-O-glucosyltransferase Tf3GT gene is expressed in Escherichia coli cells, the recombinant flavonoid 3-O-glucosyltransferase protein can promote anthocyanin and UDP-glucose to react and generate the anthocyanin. The Tf3GT coding sequence has application value in modification of varieties by a transgenic technique.

The invention discloses a rhizoma gastrodiae glucosyltransferase gene. The nucleotide sequence of the rhizoma gastrodiae glucosyltransferase gene is shown as SEQID NO:1, and an amino acid sequence asshown in SEQID NO:2 is coded. A glucosyltransferase gene sequence is screened out according to a CDS sequence provided by a rhizoma gastrodiae transcriptome, a nest type PCR primer is designed, and through amplification and splicing, an overall length sequence of the glucosyltransferase gene is obtained; a prokaryotic expression vector pGEX4T-UGT is constructed, proteins are obtained through expression and purification, a eukaryotic expression vector is constructed, subcellular localization is performed on expression of a UGT gene, glucosyltransferase is transferred into monokaryon honey mushroom mycelia by an agrobacterium tumefaciens infection method for the constructed eukaryotic expression vector pH2GW7.0 35S-UGT, transgene honey mushrooms are obtained, biosynthetic gastrodin is used,the rhizoma gastrodiae is artificially cultured by the transgene honey mushrooms, the content of gastrodin in the rhizoma gastrodiae is increased, and besides, the gastrodin can also be produced through culturing genetic engineering honey mushrooms.

The invention discloses recombinant bacteria for producing salidroside and analogue thereof, and a construction method and use. The construction method comprises the steps of synthesizing keto-decarboxylase gene synkdc and glycosyl transferase gene synyjic, and connecting to a vector pRSFDuet-1 to construct a recombinant vector pSynkdc1-yjic; enabling T7RNA polymerase gene to be free or integrated to SyBE-002447 base bacterial strain, and introducing pSynkdc1-yjic to obtain SyBE-218011 and SyBE-218013 bacterial stains; and directly integrating synkdc and synyjic to SyBE-002447 chromosome, and removing feaB and ushA in a knockout manner to obtain a SyBE-218015 bacterial strain. The bacterial strain disclosed in the invention can be used for producing salidroside and analogue thereof through fermentation, so that the problem existing in source of the salidroside and analogue thereof can be solved, and cost can be lowered.

The invention provides construction and application of a multiple gene co-expression system containing angolosamine glycosylsynthetase and glycosyltransferase. The invention is characterized by taking a streptomyces genome bank plasmid as a template; amplifying six angolosamine synthetase genes and a glycosyltransferase gene through PCR and connecting the genes in sequence and placing the genes in the lower reaches of a streptomyces promoter PactIII-actI to form a transcription unit; transferring the transcription unit to a streptomyces plasmid carrier pSET152, thus constructing a streptomyces expression plasmid pAYT55 co-expressed by multiple genes; leading the pAYT55 into a host cell streptomyces coelicolor CH999, mixedly culturing obtained engineering bacteria and streptomyces B135 of accumulated polyketide kalafungin, thus realizing bioconversion of kalafungin into a novel antibiotic with angolosamine; or directly leading pAYT55 into the streptomyces B135 and carrying out single culture to realize glycosylation of kalafungin. Therefore, by adopting the system, rare angolosamine can be synthesized in the cell and angolosamine modification can be carried out on polyketide by adopting the low substrate recognition specificity of antibiotic glycosyltransferases.

The invention discloses a method for synthesizing 3-O-glucose-glycyrrhetinic acid with an enzymic method and belongs to the technical field of biological engineering. Glycosyltransferase gene Unigene14953, Unigene20323UGT73C11, UGT73C5 and UGT73C6 from plant licorice, barbarea vulgaris or Arabidopsis are cloned or chemically synthesized, escherichia coli is preferably selected as host bacteria, and genetically engineered bacteria containing glycosyl transferase is established; recombinant glycosyl transferase serves as glycyrrhetinic acid substrate and uridine diphosphate glucose, and 3-O-glucose-glycyrrhetinic acid can be synthesized efficiently in pH value of 5.0-11.0 and at the temperature of 25-55DEG C conditions.

The invention discloses a method for preparing a rice humidity and temperature sensitive type male sterile material and a related gene. The method for preparing the rice humidity and temperature sensitive type male sterile material comprises the following steps: reducing activity of a protein in a target plant, reducing the content of the protein in the target plant, inhibiting expression of an encoding gene of the protein in the target plant, or knocking off the encoding gene of the protein in the target plant, thereby obtaining a rice humidity and temperature sensitive type male sterile plant, wherein the protein is one of which an amino acid sequence A1) or A2): A1) is sequence 2 in a sequence table; and the amino acid sequence of the sequence 2 in the sequence table is substituted and / or deleted and / or added by one or more amino acid residues and has proteins of same functions. By controlling a glycosyl transferase OsUGT gene and an encoding protein of the gene of rice, the rice humidity and temperature sensitive type male sterile material is obtained, and conversion of rice fertility under different humidity and temperature conditions is achieved.

Provided is a polynucleotide encoding a protein having an activity to transfer a sugar to the hydroxy groups at the 4′- and 7-positions of a flavone. The polynucleotide is selected from the group consisting of: (a) a polynucleotide which comprises a base sequence represented by SEQ ID NO: 1, 3, or 12; (b) a polynucleotide which hybridizes to a polynucleotide comprising a base sequence complementary to a base sequence represented by SEQ ID NO: 1, 3, or 12 under high stringency conditions, and encodes a protein having an activity to transfer a sugar to the hydroxy groups at the 4′- and 7-positions of a flavone; (c) a polynucleotide which encodes a protein comprising an amino acid sequence represented by SEQ ID NO: 2, 4, or 13; (d) a polynucleotide which encodes a protein comprising an amino acid sequence in which one or more amino acids have been deleted, substituted, inserted, and / or added in an amino acid sequence represented by SEQ ID NO: 2, 4, or 13 and having an activity to transfer a sugar to the hydroxy groups at the 4′- and 7-positions of a flavone; etc.

The object of the present invention is to provide a novel method for producing a terpene 8-glycoside.The present invention provides a method for producing a terpene 8-glycoside by means of glycosyltransferase acting on the 8-position of terpenes. The present invention provides a transformant transformed with a gene for the glycosyltransferase acting on the 8-position of terpenes and a method for producing such a transformant. The present invention provides a plant modified to suppress the expression of a protein having glycosylation activity on the 8-position of a monoterpene compound.

The invention discloses a method for preparing thermal reversible starch based gelatin with controllable gelatin strength by an enzyme method, and belongs to the technical field of starch modification. The method comprises the steps of cloning 4-alpha-Glyt (Tu alpha GT) in Thermoproteus uzoniensis (Thermoproteus uzoniensis), performing escherichia coli heterologous expression, performing enzymology nature characterization, and determining that the 4-alpha-Glyt (Tu alpha GT) is 4 alpha GT, the enzyme has good temperature stability and substrate tolerance, high-concentration starch can be catalyzed at high temperature for modification, and the side chain of branched chain starch can be prolonged. According to the method for preparing thermal reversible starch based gelatin with controllablegelatin strength by an enzyme method, the starch is used as the raw material, an appropriate amount of the 4-alpha-Glyt is added, an appropriate additive quantity and appropriate action time are selected, and the high strength anabiotic resisting starch based gelatin can be prepared.