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Grace Yim, Wenliang Wang, Maulik N Thaker, Stephanie Tan, Gerard D Wright
Modification of natural product backbones is a proven strategy for the development of clinically useful antibiotics. Such modifications have traditionally been achieved through medicinal chemistry strategies or via in vitro enzymatic activities. In an orthogonal approach, engineering of biosynthetic pathways using synthetic biology techniques can generate chemical diversity. Here we report the use of a minimal teicoplanin class glycopeptide antibiotic (GPA) scaffold expressed in a production-optimized Streptomyces coelicolor strain to expand GPA chemical diversity...
September 9, 2016: ACS Infectious Diseases
Renwen Zhang, Xiaoxue Han, Zhanfeng Xia, Xiaoxia Luo, Chuanxing Wan, Lili Zhang
A novel actinomycete strain, designated TRM 49605(T), was isolated from a desert soil sample from Lop Nur, Xinjiang, north-west China, and characterised using a polyphasic taxonomic approach. The strain exhibited antifungal activity against the following strains: Saccharomyces cerevisiae, Curvularia lunata, Aspergillus flavus, Aspergillus niger, Fusarium oxysporum, Penicillium citrinum, Candida albicans and Candida tropicalis; Antibacterial activity against Bacillus subtilis, Staphylococcus epidermidis and Micrococcus luteus; and no antibacterial activity against Escherichia coli...
October 17, 2016: Antonie Van Leeuwenhoek
Jian-Song Li, Min-Na Du, Hui Zhang, Ji Zhang, Shao-Yong Zhang, Hai-Yan Wang, An-Liang Chen, Ji-Dong Wang, Wen-Sheng Xiang
Two new milbemycin derivatives, 27-methoxylmilbemycin α31 (1) and 27-oxomilbemycin α31 (2), were isolated from the genetically engineered strain Streptomyces bingchenggensis BCJ60. Their structures were determined by 1D NMR, 2D NMR and HR-ESI-MS spectral analysis, and comparison with previous reports. The acaricidal and nematocidal capacities of compounds 1 and 2 were evaluated against Tetranychus cinnabarinus and Bursaphelenchus xylophilus, respectively. The results showed that the two new macrocyclic lactones 1 and 2 possessed potent acaricidal and nematocidal activities...
October 16, 2016: Natural Product Research
Yemin Wang, Zhengsheng Tao, Hualiang Zheng, Fei Zhang, Qingshan Long, Zixin Deng, Meifeng Tao
Many high-value secondary metabolites are assembled by very large multifunctional polyketide synthases or non-ribosomal peptide synthetases encoded by giant genes, for instance, natamycin production in an industrial strain of Streptomyces gilvosporeus. In this study, a large operon reporter-based selection system has been developed using the selectable marker gene neo to report the expression both of the large polyketide synthase genes and of the entire gene cluster, thereby facilitating the selection of natamycin-overproducing mutants by iterative random mutagenesis breeding...
October 13, 2016: Metabolic Engineering
Sabitha Papineni, Dale W Fletcher, Gary L Cromwell, Ricardo D Ekmay
Broiler chickens are fast growing monogastric animals considered a sensitive test species to evaluate the safety and nutritional equivalence between transgenic and non-transgenic grains as part of the human safety evaluation process. DAS-44406-6 soybean expresses three herbicide-tolerant proteins: the aryloxyalkanoate dioxygenase-12 (AAD-12) enzyme which provides tolerance to 2,4-dichlorophenoxyacetic acid (2,4-D) herbicides, the double-mutant 5-enolpyruvylshikimate-3-phosphate synthase (2mEPSPS) enzyme encoded by a modified version of the epsps gene from maize (Zea mays), which provides tolerance to glyphosate herbicides, and the phosphinothricin acetyltransferase (PAT) enzyme from Streptomyces viridochromogenes, which provides tolerance to glufosinate herbicides...
October 14, 2016: Poultry Science
Yosra Ben-Fadhel, Sabrina Saltaji, Mohamed Ali Khlifi, Stephane Salmieri, Khanh Dang Vu, Monique Lacroix
The antimicrobial activity of essential oils (EOs), organic acid (OA) salts and natamycin, a natural antifungal produced during fermentation by the bacterium Streptomyces natalensis, was assessed against four pathogens (Escherichia coli O157:H7, Listeria monocytogenes, Salmonella Typhimurium and Aspergillus niger). The Minimum Inhibitory Concentration (MIC) of each antimicrobial (AM) was assessed to determine their efficiency on tested microbial species in order to select the most efficient. Then, the interactions between different antimicrobial compounds showing the lowest MIC were determined by the checkerboard method...
October 11, 2016: International Journal of Food Microbiology
Hisayuki Komaki, Akira Hosoyama, Natsuko Ichikawa, Watanalai Panbangred, Yasuhiro Igarashi
We report here the draft genome sequence of Streptomyces sp. SPMA113 isolated from soil in Thailand. This strain produces a new modified peptide, prajinamide, which has adipocyte differentiation activity. The genome harbors at least 30 gene clusters for synthases of polyketide and nonribosomal peptide, suggesting its potential to produce diverse secondary metabolites.
October 13, 2016: Genome Announcements
James A deMayo, Kendra R Maas, Jonathan L Klassen, Marcy J Balunas
Streptomyces sp. AVP053U2 is a marine bacterium isolated from Styela clava, a tunicate collected in Long Island Sound. Here, we report a draft genome for this bacterium, which was found to contain a high capacity for secondary metabolite production based on analysis and identification of numerous biosynthetic gene clusters.
October 13, 2016: Genome Announcements
Wenlong Cai, Xiachang Wang, Sherif I Elshahawi, Larissa V Ponomareva, Xiaodong Liu, Matthew R McErlean, Zheng Cui, Ashley L Arlinghaus, Jon S Thorson, Steven G Van Lanen
Four new Y-type actinomycin analogues named Y6-Y9 (1-4) were isolated and characterized from the scale-up fermentation of the Streptomyces sp. strain Gö-GS12, as well as actinomycin Zp (5), which was, for the first time, isolated as a natural product. Structures of the new compounds were elucidated by the cumulative analyses of NMR spectroscopy and HRMS. The 4-hydroxythreonine on the β-ring of 1 uniquely undergoes both a rearrangement by a 2-fold acyl shift and an additional ring closure with the amino group of the phenoxazinone chromophore, and the α-rings of 4 and 5 contain a rare 5-methyl proline...
October 13, 2016: Journal of Natural Products
Si-Sun Choi, Hee-Ju Nah, Hye-Rim Pyeon, Eung-Soo Kim
Tautomycetin (TMC) is a natural product with a linear structure that includes an ester bond connecting a dialkylmaleic moiety to a type I polyketide chain. Although TMC was originally identified as an antifungal antibiotic in the late 1980s, follow-up studies revealed its novel immunosuppressant activity. Specifically, TMC exhibited a mechanistically unique immunosuppressant activity about 100 times higher than that of cyclosporine A, a widely used immunosuppressant drug. Interestingly, a structurally close relative, tautomycin (TTM), was reported to not possess TMC-like immunosuppressant activity, suggesting that a distinctive polyketide moiety of TMC plays a critical role in immunosuppressant activity...
October 12, 2016: Journal of Industrial Microbiology & Biotechnology
Irene Saugar, Brian Molloy, Eloisa Sanz, María Blanca Sánchez, María Fernández-Lobato, Antonio Jiménez
Antibiotic A201A produced by Saccharothrix mutabilis subsp. capreolus NRRL3817 contains an aminonucleoside (N(6), N(6)-dimethyl-3'-amino-3'-deoxyadenosyl), a polyketide (α-methyl-p-coumaric acid) and a disaccharide moiety. The heterologous expression in Streptomyces lividans and Streptomyces coelicolor of a S. mutabilis genomic region of ~34 kb results in the production of A201A, which was identified by microbiological, biochemical and physicochemical approaches, and indicating that this region may contain the entire A201A biosynthetic gene cluster (ata)...
October 12, 2016: Journal of Antibiotics
Zhikai Guo, Guohui Pan, Zhengren Xu, Dong Yang, Hindra, Xiangcheng Zhu, Yong Huang, Li-Xing Zhao, Yi Jiang, Yanwen Duan, Ben Shen
Isofuranonaphthoquinones (IFQs) and Isoindolequinones (IIQs) comprise a small family of natural products, with the latter ones are especially uncommon in nature. Here we report the discovery of seven new IFQs, IFQ A-G (1-7), and three new IIQs, IIQ A-C (8-10), along with the known anthraquinone desoxyerythrolaccin (11), from Streptomyces sp. CB01883, expanding the chemical diversity of this family of natural products. The structures of these natural products were established on the basis of their HR-ESI-MS and nuclear magnetic resonance (NMR) spectroscopic data...
October 12, 2016: Journal of Antibiotics
Yutong Shi, Chengqian Pan, Bibi Nazia Auckloo, Xuegang Chen, Chen-Tung Arthur Chen, Kuiwu Wang, Xiaodan Wu, Ying Ye, Bin Wu
Marine hydrothermal microorganisms respond rapidly to the changes in the concentrations and availability of metals within hydrothermal vent microbial habitats which are strongly influenced by elevated levels of heavy metals. Most hydrothermal vent actinomycetes possess a remarkable capability for the synthesis of a broad variety of biologically active secondary metabolites. Major challenges in the screening of these microorganisms are to activate the expression of cryptic biosynthetic gene clusters and the development of technologies for efficient dereplication of known compounds...
October 11, 2016: Applied Microbiology and Biotechnology
Arshia Amin, Iftikhar Ahmed, Nauman Khalid, Ghenijan Osman, Inam Ullah Khan, Min Xiao, Wen-Jun Li
A Gram-staining positive, non-motile, rod-shaped, catalase positive and oxidase negative bacterium, designated NCCP-1331(T), was isolated from a hot water spring soil collected from Tatta Pani, Kotli, Azad Jammu and Kashmir, Pakistan. The isolate grew at a temperature range of 18-40 °C (optimum 30 °C), pH 6.0-9.0 (optimum 7.0) and with 0-6 % NaCl (optimum 2 % NaCl (w/v)). The phylogenetic analysis based on 16S rRNA gene sequence revealed that strain NCCP-1331(T) belonged to the genus Streptomyces and is closely related to Streptomyces brevispora BK160(T) with 97...
October 11, 2016: Antonie Van Leeuwenhoek
Marina Borisova, Rosmarie Gaupp, Amanda Duckworth, Alexander Schneider, Désirée Dalügge, Maraike Mühleck, Denise Deubel, Sandra Unsleber, Wenqi Yu, Günther Muth, Markus Bischoff, Friedrich Götz, Christoph Mayer
: Peptidoglycan recycling is a metabolic process by which Gram-negative bacteria reutilize up to half of their cell wall within one generation during vegetative growth. Whether peptidoglycan recycling also occurs in Gram-positive bacteria has so far remained unclear. We show here that three Gram-positive model organisms, Staphylococcus aureus, Bacillus subtilis, and Streptomyces coelicolor, all recycle the sugar N-acetylmuramic acid (MurNAc) of their peptidoglycan during growth in rich medium...
October 11, 2016: MBio
Xiufang Zhang, Xuewei Ye, Weiyun Chai, Xiao-Yuan Lian, Zhizhen Zhang
An extract prepared from the culture of a marine-derived actinomycete Streptomyces sp. ZZ338 was found to have significant antimicrobial and antiproliferative activities. A chemical investigation of this active extract resulted in the isolation of three known bioactive actinomycins (1-3) and two new metabolites (4 and 5). The structures of the isolated compounds were identified as actinomycins D (1), V (2), X0β (3), 2-acetylamino-3-hydroxyl-4-methyl-benzoic acid methyl ester (4), and N-1S-(4-methylaminophenylmethyl)-2-oxo-propyl acetamide (5) based on their nuclear magnetic resonance (NMR) and high resolution electrospray ionization mass spectroscopy (HRESIMS) data as well as their optical rotation...
October 11, 2016: Marine Drugs
Maxime Toussaint, Cyril Bontemps, Arnaud Besserer, Laurence Hotel, Philippe Gérardin, Pierre Leblond
Fungal biodegradation of wood is one of the main threats regarding its use as a material. So far, the detection of this decaying process is empirically assessed by loss of mass, when the fungal attack is advanced and woody structure already damaged. Being able to detect fungal attack on wood in earlier steps is thus of special interest for the wood economy. In this aim, we designed here a new diagnostic tool for wood degradation detection based on the bacterial whole-cell biosensor technology. It was designed in diverting the soil bacteria Streptomyces CebR sensor system devoted to cellobiose detection, a cellulolytic degradation by-product emitted by lignolytic fungi since the onset of wood decaying process...
October 8, 2016: Journal of Biotechnology
Yue Zhang, Chun-Yan Lin, Xiao-Mei Li, Zheng-Kun Tang, Jianjun Qiao, Guang-Rong Zhao
The polyether ionophore antibiotic monensin is produced by Streptomyces cinnamonensis and is used as a coccidiostat for chickens and growth-promoting agent for cattle. Monensin biosynthetic gene cluster has been cloned and partially characterized. The GntR-family transcription factor DasR regulates antibiotic production and morphological development in Streptomyces coelicolor and Saccharopolyspora erythraea. In this study, we identified and characterized the two-level regulatory cascade of DasR to monensin production in S...
October 8, 2016: Journal of Industrial Microbiology & Biotechnology
Mohammad F Mehbub, Jason E Tanner, Stephen J Barnett, Christopher M M Franco, Wei Zhang
Sponge-associated bacteria play a critical role in sponge biology, metabolism and ecology, but how they interact with their host sponges and the role of these interactions are poorly understood. This study investigated the role of the interaction between the sponge Aplysilla rosea and its associated actinobacterium, Streptomyces ACT-52A, in modifying sponge microbial diversity, metabolite profile and bioactivity. A recently developed experimental approach that exposes sponges to bacteria of interest in a controlled aquarium system was improved by including the capture and analysis of secreted metabolites by the addition of an absorbent resin in the seawater...
October 7, 2016: Applied Microbiology and Biotechnology
Xuewei Pang, Yitao Zheng, Xianting Qiao, Quangui Mao, Qian Ma, Ruifang Ye
Lincomycin is a lincosamide antibiotic produced by Streptomyces lincolnensis. Through mutagenesis by ethylmethansulfonate (EMS) and ultraviolet (UV) irradiation repeatedly, M2 was picked out in plate with glutamine and propylproline orderly. In 50-L stirred bioreactor, the production of lincomycin, fermented by M2, was increased to 8136 u/ml under the optimal condition as compared to original strainS. lincolnensis 07-5 (6634 u/ml). Two-dimensional gel electrophoresis (2-D GE) and mass spectrometry (MS) shown LmbG, LmbI and acetohydroxy acid isomeroreductase were remarkably synthesized in M2...
August 15, 2016: Preparative Biochemistry & Biotechnology
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