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Johan Andersen-Ranberg, Kenneth Thermann Kongstad, Majse Nafisi, Dan Staerk, Finn Okkels, Uffe Hasbro Mortensen, Birger Lindberg Møller, Rasmus John Normand Frandsen, Rubini Kannangara
Carminic acid is a C-glucosylated octaketide anthraquinone and the main constituent of the natural dye carmine (E120) possessing unique coloring, stability and solubility properties. Despite being used since ancient times, longstanding efforts to elucidate its route of biosynthesis have been unsuccessful. Herein is reported a novel combination of enzymes derived from a plant (Aloe arborescens, Aa), a bacterium (Streptomyces sp R1128, St), and an insect (Dactylopius coccus, Dc) that allows for the biosynthesis of the C-glucosylated anthraquinone, dcII, a precursor for carminic acid...
July 18, 2017: Chembiochem: a European Journal of Chemical Biology
Xiaoshu Xu, Chao Wang, Jun Chen, Sheng Yang
Streptomyces virginiae phenylpyruvate decarboxylase (PPDC) has not been identified before. Two putative branched-chain α-keto acid dehydrogenase subunit genes bkdC and bkdD from S. virginiae are similar to halves of other PPDC coding sequences. We cloned and characterized them biochemically in this work. The two proteins formed a stable complex attested by pull-down assay, consistent with the finding that their soluble expression was obtained only when they were coexpressed in Escherichia coli. The subunits were redesignated as SvPPDCα and SvPPDCβ, because the SvPPDCα/β complex catalyzed the conversion of phenylpyruvate to phenylacetaldehyde, reflecting the nature of the enzyme...
July 18, 2017: ACS Chemical Biology
Fengjuan Lu, Yanyan Hou, Heming Zhang, Yiwen Chu, Haiyang Xia, Yongqiang Tian
The numerous secondary metabolites in Streptomyces spp. are crucial for various applications. For example, cephamycin C is used as an antibiotic, and avermectin is used as an insecticide. Specifically, antibiotic yield is closely related to many factors, such as the external environment, nutrition (including nitrogen and carbon sources), biosynthetic efficiency and the regulatory mechanisms in producing strains. There are various types of regulatory genes that work in different ways, such as pleiotropic (or global) regulatory genes, cluster-situated regulators, which are also called pathway-specific regulatory genes, and many other regulators...
August 2017: 3 Biotech
Robert A Hill, Andrew Sutherland
A personal selection of 32 recent papers is presented covering various aspects of current developments in bioorganic chemistry and novel natural products such as svetamycin B from a Streptomyces species.
July 18, 2017: Natural Product Reports
Cristopher A Boya P, Hermógenes Fernández-Marín, Luis C Mejía, Carmenza Spadafora, Pieter C Dorrestein, Marcelino Gutiérrez
The fungus-growing ant-microbe symbiosis is an ideal system to study chemistry-based microbial interactions due to the wealth of microbial interactions described, and the lack of information on the molecules involved therein. In this study, we employed a combination of MALDI imaging mass spectrometry (MALDI-IMS) and MS/MS molecular networking to study chemistry-based microbial interactions in this system. MALDI IMS was used to visualize the distribution of antimicrobials at the inhibition zone between bacteria associated to the ant Acromyrmex echinatior and the fungal pathogen Escovopsis sp...
July 17, 2017: Scientific Reports
Hans-Jörg Frasch, Sander S van Leeuwen, Lubbert Dijkhuizen
Polyfructans are synthesized from sucrose by plants (mostly inulin) and by both Gram-negative and Gram-positive bacteria (mostly levan). In the phylum Actinobacteria only levan synthesis by Actinomyces species has been reported. We have identified a putative fructansucrase gene (hugO) in Streptomyces viridochromogenes DSM40736 (Tü494). HugO was heterologously expressed and biochemically characterized. HPSEC-MALLS and 2D-1H-13C nuclear magnetic resonance (NMR) spectroscopy analysis showed that the fructan polymer produced in vitro has an Molecular Weight of 2...
July 17, 2017: Microbiology
Hildgund Schrempf
Pioneering biochemical, immunological, physiological and microscopic studies in combination with gene cloning allowed uncovering previously unknown genes encoding proteins of streptomycetes to target crystalline chitin and cellulose as well as their soluble degradation-compounds via binding protein dependent transporters. Complementary analyses provoked an understanding of novel regulators governing transcription of selected genes. These discoveries induced detecting close and distant homologues of former orphan proteins encoded by genes from different bacteria...
June 20, 2017: Carbohydrate Research
Jayaram Nanthini, Su Yean Ong, Kumar Sudesh
Rubber materials have greatly contributed to human civilization. However, being a polymeric material does not decompose easily, it has caused huge environmental problems. On the other hand, only few bacteria are known to degrade rubber, with studies pertaining them being intensively focusing on the mechanism involved in microbial rubber degradation. The Streptomyces sp. strain CFMR 7, which was previously confirmed to possess rubber-degrading ability, was subjected to whole genome sequencing using the single molecule sequencing technology of the PacBio® RS II system...
July 12, 2017: Gene
Rachelle El Khoury, Florence Mathieu, Ali Atoui, Hiba Kawtharani, Anthony El Khoury, Charbel Afif, Richard G Maroun, André El Khoury
Ochratoxin A (OTA) is one of the most important mycotoxins, and contaminates several agricultural products, particularly cereals, grapes, maize, barley, spices and coffee. The aim of this project was to reduce the levels of OTA by supplementing the artificially contaminated solutions with seven strains of actinobacteria (AT10, AT8, SN7, MS1, ML5, G10 and PT1) in order to evaluate their capacity for binding and metabolizing the OTA, as well as their ability to reduce the expression of the genes responsible for its production in A...
July 14, 2017: Toxins
Marta Maciejewska, Delphine Adam, Aymeric Naômé, Loïc Martinet, Elodie Tenconi, Magdalena Całusińska, Philippe Delfosse, Marc Hanikenne, Denis Baurain, Philippe Compère, Monique Carnol, Hazel A Barton, Sébastien Rigali
Moonmilk is a karstic speleothem mainly composed of fine calcium carbonate crystals (CaCO3) with different textures ranging from pasty to hard, in which the contribution of biotic rock-building processes is presumed to involve indigenous microorganisms. The real microbial input in the genesis of moonmilk is difficult to assess leading to controversial hypotheses explaining the origins and the mechanisms (biotic vs. abiotic) involved. In this work, we undertook a comprehensive approach in order to assess the potential role of filamentous bacteria, particularly a collection of moonmilk-originating Streptomyces, in the genesis of this speleothem...
2017: Frontiers in Microbiology
Christian Grumaz, Yevhen Vainshtein, Philipp Kirstahler, Stephan Luetz, Matthias Kittelmann, Kirsten Schroer, Fabian K Eggimann, Rico Czaja, Andreas Vogel, Thomas Hilberath, Anne Worsch, Marco Girhard, Vlada B Urlacher, Marcel Sandberg, Kai Sohn
The three Actinobacteria strains Streptomyces platensis DSM 40041, Pseudonocardia autotrophica DSM 535, and Streptomyces fradiae DSM 40063 were described to selectively oxyfunctionalize several drugs. Here, we present their draft genomes to unravel their gene sets encoding promising cytochrome P450 monooxygenases associated with the generation of drug metabolites.
July 13, 2017: Genome Announcements
Richard Donegan-Quick, Zane A Gibbs, Patricia O Amaku, Joshua T Bernal, Dana A M Boyd, Angela R Burr, Rainna E Coelho, Akpedje S Dossou, Ryan M Henry, Mai Huynh, Thalia A Kanani-Hendijani, Guillermina Martinez, Tianeaka O McClendon-Moss, Sergio Orozco, Johnny M San Martin, Kaitlyn E Stoddart, Madison M Stringer, Rachel L Villegas, Subhayu Nayek, Nikita Suri, Rebecca A Garlena, Daniel A Russell, Lee E Hughes
Cluster BG of the actinobacteriophage was formed upon discovery of five novel bacteriophages isolated by enrichment from their host, Streptomyces griseus subsp. griseus strain ATCC 10137. Four members of this cluster (BabyGotBac, Maih, TP1605, and YDN12) share over 89% average nucleotide identity, while the other (Xkcd426) has only 72% similarity to other cluster members.
July 13, 2017: Genome Announcements
Antonella Scaglione, Maria Rosaria Fullone, Linda Celeste Montemiglio, Giacomo Parisi, Carlotta Zamparelli, Beatrice Vallone, Carmelinda Savino, Ingeborg Grgurina
We determined the crystal structure of Thr1, the self-standing adenylation domain involved in the nonribosomal-like biosynthesis of free 4-chlorothreonine in Streptomyces sp. OH-5093. Thr1 shows two monomers in the crystallographic asymmetric unit with different relative orientations of the C- and N-terminal subdomains both in the presence of substrates and in the unliganded form. Co-crystallization with substrates, ATP and L-threonine, yielded one monomer containing the two substrates and the other in complex with L-threonine adenylate, locked in a post-adenylation state...
July 13, 2017: FEBS Journal
Parul Vatsa-Portugal, Aziz Aziz, Marine Rondeau, Sandra Villaume, Hamid Morjani, Christophe Clément, Essaid Ait Barka
Gray mold, caused by Botrytis cinerea, is one of the most destructive diseases of grapevine and is controlled with an intense application of fungicides. As alternatives to chemicals, beneficial microbes may promote plant health by stimulating the plant's immune system. An actinomycete, Streptomyces anulatus S37, has been screened from the rhizosphere microbiome of healthy Vitis vinifera on the basis of its ability to promote grapevine growth and to induce resistance against various phytopathogens, including B...
2017: Frontiers in Plant Science
Dongyang Wang, Cong Wang, Pengyan Gui, Haishan Liu, Sameh M H Khalaf, Elsayed A Elsayed, Mohammed A M Wadaan, Wael N Hozzein, Weiming Zhu
In the process of profiling the secondary metabolites of actinobacteria isolated from the Saudi coastal habitats for production of antibiotics and anti-cancer drugs, the cultures of strain WH1 that was identified as Streptomyces heliomycini exhibited strong antibacterial activity against Staphylococcus aureus. By means of MS and NMR techniques, the active compounds were characterized as actinomycins X0β, X2, and D, respectively. The research on the productivity of this strain for actinomycins revealed that the highest production of actinomycins X0β, X2, and D was reached in the medium MII within 5% salinity and pH 8...
2017: Frontiers in Microbiology
Nicolle F Som, Daniel Heine, Neil A Holmes, John T Munnoch, Govind Chandra, Ryan F Seipke, Paul A Hoskisson, Barrie Wilkinson, Matthew I Hutchings
Streptomyces bacteria make numerous secondary metabolites, including half of all known antibiotics. Production of antibiotics is usually coordinated with the onset of sporulation but the cross regulation of these processes is not fully understood. This is important because most Streptomyces antibiotics are produced at low levels or not at all under laboratory conditions and this makes large scale production of these compounds very challenging. Here, we characterize the highly conserved actinobacterial two-component system MtrAB in the model organism Streptomyces venezuelae and provide evidence that it coordinates production of the antibiotic chloramphenicol with sporulation...
2017: Frontiers in Microbiology
S Anuradha, K Shravan Kumar, S Bhama, V Kishan
Tuberculosis, caused by Mycobacterium tuberculosis, continues to be a serious public health problem around the world, and it urges the need for development of new antitubercular drugs. An antibiotic producing strain, Streptomyces luridus (MTCC 4402) was earlier isolated from soil by our group. In this work, the phylogenic status was established by 16S rRNA gene sequence analysis. The strain was found to be active against clinically resistant strains. The culture was grown in shake flasks in a medium containing cornsteep liquor, glucose, CaCO(3), soyabean meal and starch...
September 2016: Indian Journal of Experimental Biology
Jian Ma, Hui Lei, Xiu Chen, Xiaoxu Bi, Yi Jiang, Li Han, Xueshi Huang
Three new metabolites (2-4), together with one known compound, GTRI-02, (1) were isolated from a fermentation broth of Streptomyces violaceoruber derived from Equus burchelli feces. The structures of the new compounds 2-4 were established using comprehensive NMR spectroscopic data analysis as well as UV, IR and MS data. The anti-inflammatory activity of compounds 1-4 was tested by examining their ability to inhibit nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells...
July 12, 2017: Journal of Antibiotics
Jan Rinkel, Patrick Rabe, Xinlu Chen, Tobias G Köllner, Feng Chen, Jeroen S Dickschat
Two diterpene cyclases, one from the social amoeba Dictyostelium discoideum and the other from the bacterium Streptomyces clavuligerus, with products containing a Z-configured double bond between the original C2 and C3 of geranylgeranyl diphosphate, were extensively investigated for their mechanisms through isotopic labelling experiments. The participation of geranyllinalyl diphosphate, in analogy to the role of linalyl and nerolidyl diphosphate for mono- and sesquiterpene biosynthesis, as an intermediate towards diterpenes with a Z-configured C2=C3 double bond is discussed...
July 11, 2017: Chemistry: a European Journal
Amanda K Chaplin, Michael T Wilson, Jonathan A R Worrall
Dye decolourising peroxidases are the most recent family of haem peroxidases to be discovered. The oxidising potential of these enzymes is driven by the formation of ferryl intermediates that enables them to oxidise synthetic dye molecules that are widely used in the textile industry. We have investigated the catalytic cycle of a dye decolourising peroxidase (DtpA) from a biotechnologically important bacterium Streptomyces lividans. Using a combination of steady-state and stopped-flow kinetic investigations, we have determined the rate constants for all steps in the catalytic cycle with a range of substrate molecules...
July 11, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
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