87 results about "Streptomyces thioluteus" patented technology

The invention discloses a streptomyces parvus and application thereof for preparing daptomycin. The strain is reserved in the CCTCC and has the reservation number of CCTCC NO: M2010136, and the reservation data is June 4, 2010. The method for preparing the daptomycin is as follows: a, taking streptomyces parvus CCTCC NO: M2010136 as a fermentation strain; b, strain cultivation: inoculating slope lawn into a shake flask seeding tank to cultivate to obtain shake flask seeding liquid; inoculating the shake flask seeding liquid into the seeding tank to be cultivated; inoculating the seeding tank culture solution into fermentation tank culture medium to be cultivated, and collecting fermentation liquor; carrying out feed supplement in the fermentation and cultivation process; and c, extracting a fermentation product. The fermentation technology provided by the invention has stable production capability, high fermentation unit and few fermentation byproducts by the pilot plant test and the experiment in a 10-ton fermentation tank, greatly lowers post-extracting difficulty and is suitable for industrial production.

In accordance with the present invention, a novel aromatic prenyltransferase, Orf2 from Streptomyces sp. strain CL190, involved in naphterpin biosynthesis has been identified and the structure thereof elucidated. This prenyltransferase catalyzes the formation of a C—C bond between a prenyl group and a compound containing an aromatic nucleus, and also displays C—O bond formation activity. Numerous crystallographic structures of the prenyltransferase have been solved and refined, e.g., (1) prenyltransferase complexed with a buffer molecule (TAPS), (2) prenyltransferase as a binary complex with geranyl diphosphate (GPP) and Mg²⁺, and prenyltransferase as ternary complexes with a non-hydrolyzable substrate analogue, geranyl S-thiolodiphosphate (GSPP) and either (3) 1,6-dihydroxynaphthalene (1,6-DHN), or (4) flaviolin (i.e., 2,5,7-trihydroxy-1,4-naphthoquinone, which is the oxidized product of 1,3,6,8-tetrahydroxynaphthalene (THN)). These structures have been solved and refined to 1.5 Å, 2.25 Å, 1.95 Å and 2.02 Å, respectively. This first structure of an aromatic prenyltransferase displays an unexpected and non-canonical (β/α)-barrel architecture. The complexes with both aromatic substrates and prenyl containing substrates and analogs delineate the active site and are consistent with a proposed electrophilic mechanism of prenyl group transfer. These structures also provide a mechanistic basis for understanding prenyl chain length determination and aromatic co-substrate recognition in this structurally unique family of aromatic prenyltransferases. This structural information is useful for predicting the aromatic prenyltransferase activity of proteins.

The present invention provides cloning sequencing, analyzing, function research of a biosynthesis gene cluster of an antibiotic-Azinomycin B having antitumor activity produced by streptomyces, and its application. The whole gene cluster includes 34 genes: one repeatedly using I type polyketide synthase gene; two naphthalene ring modification enzyme genes; 8 non-ribosomal polypeptide skeleton synthesis and modification enzyme genes; 11 non-natural amino acid structure unit synthase genes; 1 resistance gene; 3 post modification enzyme genes and 8 genes which functions are not determined. The genetic operation of the biosynthesis gene breaks the synthesis of Azinomycin B; the precursor compound is produced by the heterologous expression of synthesis gene and modification gene of naphthalene ring. The gene of the invention and the protein can be used for searching and finding compound or gene, protein applied in medical, industry or agriculture.

The invention discloses a detection kit for identifying and diagnosing whether an equine animal is infected with piroplasmosis or not, and a preparation method and a using method thereof. A detection film for detecting equine piroplasmosis and a piroplasmosis universal primer are arranged in the kit for detecting the equine piroplasmosis. The using method of the kit comprises the following steps:extracting DNA (deoxyribonucleic acid) from blood of a horse to be detected, further using the piroplasmosis universal primer to perform amplification, combining an amplification product with the detection film, enabling biotin at the terminal of a PCR (polymerase chain reaction) product to be in action with streptavidin-peroxidase, and then playing a catalysis role in enabling a substrate of peroxidase, namely an enhanced chemiluminescence reagent (ECL-detection) to emit fluorescence, thereby exposing an X-photosensitive film; and performing development and fixing treatment on the film so asto emerge a shadow in a region corresponding to specificity hybridization of a probe on the detection film and the PCR product, and further judging whether the detected animal is infected with the piroplasmosis or not according to whether the shade is left on the film or not.

This invention relates to a new class of polyene polyketides, their pharmaceutically acceptable salts and derivatives, and to methods for obtaining the compounds. One method of obtaining these compounds is by cultivation of novel strains of Streptomyces aizunensis; another method involves expression of biosynthetic pathway genes in transformed host cells. The present invention further relates to the novel strains of Streptomyces aizunensis used to produce these compounds, to the use of these compounds and their pharmaceutically acceptable salts and derivatives as pharmaceuticals, in particular to their use as inhibitors of fungal cell growth and cancer cell growth. The invention also relates to pharmaceutical compositions comprising these novel polyketides or a pharmaceutically acceptable salts or derivatives thereof. Finally, the invention relates to novel polynucleotide sequences and their encoded proteins, which are involved in the biosynthesis of these novel polyketides.

The invention relates to an nsdBmgh gene of Streptomyces roseoflavus Men-myco-93-63 as well as a preparation method and application thereof. In the invention, primers Ns8F and Ns8R are designed by utilizing an important negative regulator gene nsdB sequence in a Streptomyces coelicolor A3(2) antibiotic metabolic pathway, and genomic DNA (deoxyribonucleic acid) of Streptomyces roseoflavus Men-myco-93-63 is amplified to obtain a 1121bp segment; and two ends of a target sequence are extended by utilizing a primer anchoring polymerase chain reaction) (NPA-PCR ) method by a non-specific primer, thus obtaining the nsdBmgh gene of Streptomyces roseoflavus Men-myco-93-63. The preparation of the nsdBmgh gene provides an important basis for further researching and verifying the Streptomyces roseoflavus antibiotic metabolic pathway and regulatory mechanism, and establishes an important base for obtaining high-yield antibiotic gene engineering strains.

The invention discloses a recombined streptomycete, a construction method of the recombined streptomycete and a method for increasing the antibiotic yield. The recombined streptomycete over-expresses acetolactic acid synthase small subunit ilvH. The recombined streptomycete over-expresses acetolactic acid synthase to adjust subunit genes, and the yield of products such as antibiotics for conducting secondary metabolism with L-isoleucine and/or L-valine and/or L-leucine as precursors/a precursor can be remarkably increased.

The present invention provides a tomaymycin biosynthetic gene cluster of Streptomyces species FH6421, and its use for producing 11-de-O-methyltomaymycin.

The invention provides a gene engineering strain Streptomyces chattanoogensis. The preservation registration number of the gene engineering strain Streptomyces chattanoogensis is CGMCC No.7182, the nucleotide sequence of the gene engineering strain Streptomyces chattanoogensis is represented by SEQ ID NO.1, and the gene engineering strain Streptomyces chattanoogensis is obtained through the genetic construction of a rate-limiting enzyme in the biosynthetic way of natamycin. Compared with gene engineering strain Streptomyces chattanoogensis L10, the gene engineering strain Streptomyces chattanoogensis L11 has the advantages of more stable hereditary characters, improvement of the natamycin fermentation unit to 3.12g/L from 2.21g/L, shortening of the natamycin fermentation period to 120h from 144h, improvement of the natamycin output by 40%, shortening the fermentation period by 24h, and reduction of the industrialized production process, and can be applied to the generation of natamycin.

This invention relates to an eye use transmission system of macrolide type antibiotic hyaluronic acid natrium. The goal of this invention is to provide a macrolide type antibiotic eye use medicine preparation with carrier is hyaluronic acid or its salt. It is used to cure germ eye region infection. The macrolide type antibiotic in this invention includes antibiotic that has 14 yuan,15yuan, 16yuan large ring construction features , for example, natural antibiotic bring by streptomycete erythromycin, josamycin, spiramycin, medemycin etc. and semisynthesis derivant from by structure modification of natural antibiotic, such as roxithromycin, azithromycin, clarithromycin, rokitamycin, telithromycin.

The invention discloses streptomyces thioluteus St-79, and the preservation number of the streptomyces thioluteus St-79 is CCTCC (China Center for Type Culture Collection) NO: M 2020962. The application of the streptomyces thioluteus St-79 strain is as follows: the germination of rice seeds is promoted, the bacterial blight of rice is prevented and treated, and the pathogenic bacteria of plants are inhibited.

The invention relates to mutants of a fatty acid adenosine monophosphate (AMP) ligase and application of the mutants, and belongs to the field of bioengineering. The fatty acid AMP ligase comes from streptomyces roseosporus. The 296th glycine of the fatty acid AMP ligase is changed into alanine, and the 302th isoleucine of the fatty acid AMP ligase is changed into valine to respectively obtain the mutants pAL296 and pAL302. The mutants of the fatty acid AMP ligase can improve the binding level with exogenous precursor decanoic acid to enhance the yield of daptomycin. According to the invention, an encoding gene dptE of the fatty acid AMP ligase is subjected to site-directed mutagenesis in vitro by using computer simulation, overlap extension PCR and site-directed mutagenesis technologies to screen out the mutants pAL296 and pAL302 of which the affinities are obviously improved, recombinant shuttle plasmids pAK296 and pAK302 are constructed and sequentially led to the streptomyces roseosporus, and zygotes are screened to obtain streptomyces roseosporus DCE296 and DCE302 of the fatty acid AMP ligase with improved substrate affinities to lay a foundation for improving the production level of daptomycin.

The present invention provides a construction method for efficient biosynthesis of streptomycete drugs. The construction method comprises: based on an inducible promoter O[R]O[lac] and a strong promoter ermEp<*>, firstly constructing a gradient induction expression system in streptomycete; controlling the expression level of target gene through the gradient induction, and carrying out coupled analysis on the relationship between the expression level of the target gene and the yield of the target drug so as to reveal the rate-limiting reaction in the drug biosynthesis path and the suitability of the rate-limiting enzyme; and through a constitutive promoter ermEp<*>, rationally carrying out series coupling on the encoding genes highly expressing the relevant rate-limiting enzyme so as to obtain a strain of the high-yield S Chattanoogensis producing strain L12, and transporting the strain to the China General Microbiological Culture Collection Center to preserve, wherein the preservation number is CGMCC No.10157. According to the present invention, the shake flask fermentation results show that the Natamycin yield in the S Chattanoogensis L12 is 3.3 times the yield in the S Chattanoogensis L10, and the 50 L fermentation tank small test results show that the highest yield achieves 15.7 g/L; and the method of the present invention has characteristics of efficiency, accuracy and simple operation, and is generally suitable for other streptomycetes.

The invention discloses a straw fiber seedling-raising substrate for colonizing biocontrol bacteria, a production method of the straw fiber seedling-raising substrate, and a two-step biocontrol bacteria colonizing method of the straw fiber seedling-raising substrate, and belongs to the technical field of crop colonization biocontrol bacteria. Specifically the two-step biocontrol bacteria colonizing method comprises the following steps: the first step is the colonization of a biocontrol bacteria powder mixed with the substrate, the spray colonization of a biocontrol bacteria water agent, or thespray colonization of a biocontrol bacteria liquid; and the second step is that 10-15 days after the straw fiber substrate colonization biocontrol bacteria, the straw fiber substrate colonized with biocontrol bacteria, and crop seedlings are transplanted into a field simultaneously, and the substrate and crop seedling biocontrol bacteria are colonized in the field, wherein the used biocontrol bacteria are one or a mixture of more than one of Trichoderma aureoviride, Bacillus amyloliquefaciens, Streptomyces parvus, Talaromyces flavus, and Chaetomium aureum. According to the straw fiber seedling-raising substrate for colonizing biocontrol bacteria, the production method of the straw fiber seedling-raising substrate, and the two-step biocontrol bacteria colonizing method of the straw fiber seedling-raising substrate, the biocontrol bacteria can be effectively colonized, thereby the disease resistance of the seedlings is improved, and the stress resistance of seedling transplanting is significantly improved.

The invention relates to a formula for preparing a high-efficiency bio-organic fertilizer from organic materials and a preparation method of the high-efficiency bio-organic fertilizer. The preparation method comprises the steps: firstly, fully mixing livestock manure with auxiliary materials including peanut meal, humic acid, enzyme microorganisms, fishbone dust, soybean leaf powder and amino acid; adding bacillus amyloliquefaciens, bacillus megaterium, bacillus mucilaginosus, bacillus laterosporus, bacillus mucilaginosus, streptomyces jingyangensis, azotobacter chroococcum, actinomycetes, photosynthetic bacteria flora, lactic acid bacteria flora, saccharomycetes, bacillus coagulans, aspergillus oryzae, aspergillus niger and trichoderma viride, coarsely adjusting the moisture content and carbon nitrogen ratio of the materials according to the raw material components, mixing and fermenting; and thus obtaining the bio-organic fertilizer which does not have pesticide residues and naturally improves the crop yield.

The present invention relates to the application of environmental microbe. Especially, by means of molecular technology, one new gene is cloned from Streptomyces ansochromogenes 7100 and the gene encodes one kind of 2-streptomycete dioxyenase. The encoded product has great value in biologically degrading industrial pollutant nitroalkane and in improving environment.

The invention discloses a salinomycin strain with the class name of streptomycesalbums S-610-11, and the preservation number is CCTCCM2012492. The salinomycin high-yielding strain streptomycesalbums S-610-11 is obtained by combination of plasma mutagenesis at normal temperature under normal pressure with high-throughput synergy screening method, the content of salinomycin can be greatly improved, and the stability is good, after 5 times of continuous passages of the strain, and the salinomycin titer has no obvious change. By use of shake flask fermentation, the yield of salinomycin reaches 56000u / ml, and is improved by 70% compared with that of original strain F2-1#. The salinomycin strain is fully consistent with mutagenesis and screening requirements of industrialization salinomycin production strains, and can be applied in industrial fermentation production, and has great economic value.

The invention belongs to the field of biotechnology and genetic engineering, and specifically discloses a cloning method of antibiotics biosynthetic gene cluster based on site-specific recombination. The method comprises the following steps of: based on the site-specific recombination reaction mediated by the integrase encoded by the streptomycete bacteriophage Phi BT1, firstly, executing genetic modification on the strains, which hare generated by the antibiotics, by means of homologous recombination mode; respectively inserting the BAC (Bacterial Artificial Chromosome) vector, the resistant gene and the site-specific recombination sites attB and attP identified by the Phi T1 integrase at two ends of the targeted gene cluster, and extracting chromosome genome segments; under the action of the Phi T1 integrase, causing site-specific recombination reaction between the sites attB and attP in vitro; enabling the target gene cluster to cyclize itself, thereby realizing clone of dozens or even hundreds of kb of large-segment antibiotics biosynthetic gene clusters. The cloning method of antibiotics biosynthetic gene cluster based on site-specific recombination lays good foundation for further genetic modification of the biosynthetic gene clusters, and has better application foreground.

The invention provides a method for constructing a high-yield neomycin engineering strain streptomyces fradiae. The method comprises: introducing a neomycin biosynthetic gene cluster of streptomyces fradiae into wild streptomyces fradiae. The method can also comprise: carrying out genetic engineering modification on the neomycin biosynthetic gene cluster of streptomyces fradiae to be introduced into wild streptomyces fradiae, wherein genetic engineering modification can comprise: blocking the negative regulatory gene neoI in the neomycin biosynthetic gene cluster or blocking the negative regulatory gene neoI in the neomycin biosynthetic gene cluster while driving the transcription of a key enzyme encoding gene neoE-neoD co-transcription unit by using a strong promoter. The invention also provides high-yield neomycin streptomyces fradiae obtained by the method.

The invention discloses high-stereoselectivity methionine adenosyltransferase as well as a preparation method and application thereof. The preparation method comprises the following steps: extracting a genome of streptomyces xinghaiensis; by taking a genome as a DNA (Deoxyribose Nucleic Acid) template and adopting a PCR (Polymerase Chain Reaction) amplification technology, obtaining a gene sequence of methionine adenosyltransferase in the streptomyces xinghaiensis, namely a metK target fragment; carrying out double enzyme digestion on the metK target fragment and an expression vector pET-32a (+), and then connecting to construct a recombinant plasmid; transforming the recombinant plasmid into competent cells of escherichia coli BL21 by adopting a thermal activation method, and carrying out inducible expression by virtue of isopropyl-beta-D-thiogalactoside, so as to obtain SxMAT. According to the invention, high-stereoselectivity methionine adenosyltransferase is subjected to denaturation and renaturation later to obtain high-purity SxMAT, the SxMAT is good in stability when the temperature is 25-55 DEG C and the pH value is 8-10.5, the optical purity (ee) of the product is higher than 90%, the yield is 80%, and the in-vitro double-enzyme cascade reaction is constructed by combining the SxMAT and the fluorinase, so that the understanding of people on a fluorination pathway in streptomyces is facilitated, and the application of fluorinated natural products is derived.

The invention relates to a gene engineering strain streptomyces diastatochromogenes for high yielding of epsilon-polylysine. The construction of the gene engineering strain comprises the following steps of: step 1, constructing plasmids for expressing the aspartokinase gene ask or the dihydropyridine dicarboxylic acid synthetase gene dhdps, wherein the gene ask or dhdps is controlled by an erythromycin promoter ermE * on pIMEP plasmids; and step 2, obtaining a strain for expressing the ask or dhdps gene, namely the gene engineering strain streptomyces diastatochromogenes for high yielding of epsilon-polylysine. Experiments prove that the epsilon-polylysine production capacity of the streptomyces gene engineering strain is remarkably improved by 17.2%-25.8% compared with that of the original strain streptomyces diastatochromogenes TUST under the same condition, and an excellent strain is provided for epsilon-polylysine production.