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polyketide synthase

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https://www.readbyqxmd.com/read/28525276/chemoenzymatic-total-synthesis-and-structural-diversification-of-tylactone-based-macrolide-antibiotics-through-late-stage-polyketide-assembly-tailoring-and-c-h-functionalization
#1
Andrew N Lowell, Matthew D DeMars, Samuel T Slocum, Fengan Yu, Krithika Anand, Joseph A Chemler, Nisha Korakavi, Jennifer K Priessnitz, Sung Ryeol Park, Aaron A Koch, Pamela J Schultz, David H Sherman
Polyketide synthases (PKSs) represent a powerful catalytic platform capable of effecting multiple carbon-carbon bond forming reactions and oxidation state adjustments. We explored the functionality of two terminal PKS modules that produce the 16-membered tylosin macrocycle, using them as biocatalysts in the chemoenzymatic synthesis of tylactone and its subsequent elaboration to complete the first total synthesis of the juvenimicin, M-4365, and rosamicin classes of macrolide antibiotics via late-stage diversification...
May 19, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28522339/proteomics-analysis-of-fusarium-proliferatum-under-various-initial-ph-during-fumonisin-production
#2
Taotao Li, Liang Gong, Yong Wang, Feng Chen, Vijai Kumar Gupta, Qijie Jian, Xuewu Duan, Yueming Jiang
Fusarium proliferatum as a fungal pathogen can produce fumonisin which causes a great threat to animal and human health. Proteomic approach was a useful tool for investigation into mycotoxin biosynthesis in fungal pathogens. In this study, we analyzed the fumonisin content and mycelium proteins of Fusarium proliferatum cultivated under the initial pH5 and 10. Fumonisin production after 10days was significantly induced in culture condition at pH10 than pH5. Ninety nine significantly differently accumulated protein spots under the two pH conditions were detected using two dimensional polyacrylamide gel electrophoresis and 89 of these proteins were successfully identified by MALDI-TOF/TOF and LC-ESI-MS/MS analysis...
May 15, 2017: Journal of Proteomics
https://www.readbyqxmd.com/read/28517364/a-cryptic-pigment-biosynthetic-pathway-uncovered-by-heterologous-expression-is-essential-for-conidial-development-in-pestalotiopsis-fici
#3
Peng Zhang, Xiuna Wang, Aili Fan, Yanjing Zheng, Xingzhong Liu, Shihua Wang, Huixi Zou, Berl R Oakley, Nancy P Keller, Wen-Bing Yin
Spore pigmentation is very common in the fungal kingdom. The best studied pigment in fungi is melanin which coats the surface of single cell spores. What and how pigments function in a fungal species with multiple cell conidia is poorly understood. Here, we identified and deleted a polyketide synthase (PKS) gene PfmaE and showed that it is essential for multicellular conidial pigmentation and development in a plant endophytic fungus, Pestalotiopsis fici. To further characterize the melanin pathway, we utilized an advanced Aspergillus nidulans heterologous system for the expression of the PKS PfmaE and the Pfma gene cluster...
May 18, 2017: Molecular Microbiology
https://www.readbyqxmd.com/read/28507698/formicamycins-antibacterial-polyketides-produced-by-streptomyces-formicae-isolated-from-african-tetraponera-plant-ants
#4
Zhiwei Qin, John T Munnoch, Rebecca Devine, Neil A Holmes, Ryan F Seipke, Karl A Wilkinson, Barrie Wilkinson, Matthew I Hutchings
We report a new Streptomyces species named S. formicae that was isolated from the African fungus-growing plant-ant Tetraponera penzigi and show that it produces novel pentacyclic polyketides that are active against MRSA and VRE. The chemical scaffold of these compounds, which we have called the formicamycins, is similar to the fasamycins identified from the heterologous expression of clones isolated from environmental DNA, but has significant differences that allow the scaffold to be decorated with up to four halogen atoms...
April 1, 2017: Chemical Science
https://www.readbyqxmd.com/read/28485098/production-of-a-fungal-furocoumarin-by-a-polyketide-synthase-gene-cluster-confers-the-chemo-resistance-of-neurospora-crassa-to-the-predation-by-fungivorous-arthropods
#5
Yanxia Zhao, Jianing Ding, Weihua Yuan, Jinjin Huang, Wenxiu Huang, Yan Wang, Weifa Zheng
The formation of sexual fruiting bodies and production of polyketides are believed to be the most important strategies for fungal survival in environmental insults. In Neurospora crassa, the backbone gene of polyketide synthase gene cluster 6 (pks-6), which is expressed at lower level under vegetative growth, is highly expressed during perithecia development. Intriguingly, deletion of pks-6 does not affect perithecia maturation. How the expression of pks-6 correlates with fungal sexual development remains to be established...
May 9, 2017: Environmental Microbiology
https://www.readbyqxmd.com/read/28484706/endophytic-actinobacteria-associated-with-dracaena-cochinchinensis-lour-isolation-diversity-and-their-cytotoxic-activities
#6
Nimaichand Salam, Thi-Nhan Khieu, Min-Jiao Liu, Thu-Trang Vu, Son Chu-Ky, Ngoc-Tung Quach, Quyet-Tien Phi, Manik Prabhu Narsing Rao, Angélique Fontana, Samira Sarter, Wen-Jun Li
Dracaena cochinchinensis Lour. is an ethnomedicinally important plant used in traditional Chinese medicine known as dragon's blood. Excessive utilization of the plant for extraction of dragon's blood had resulted in the destruction of the important niche. During a study to provide a sustainable way of utilizing the resources, the endophytic Actinobacteria associated with the plant were explored for potential utilization of their medicinal properties. Three hundred and four endophytic Actinobacteria belonging to the genera Streptomyces, Nocardiopsis, Brevibacterium, Microbacterium, Tsukamurella, Arthrobacter, Brachybacterium, Nocardia, Rhodococcus, Kocuria, Nocardioides, and Pseudonocardia were isolated from different tissues of D...
2017: BioMed Research International
https://www.readbyqxmd.com/read/28484029/polyketide-mimetics-yield-structural-and-mechanistic-insights-into-product-template-domain-function-in-nonreducing-polyketide-synthases
#7
Jesus F Barajas, Gaurav Shakya, Gabriel Moreno, Heriberto Rivera, David R Jackson, Caitlyn L Topper, Anna L Vagstad, James J La Clair, Craig A Townsend, Michael D Burkart, Shiou-Chuan Tsai
Product template (PT) domains from fungal nonreducing polyketide synthases (NR-PKSs) are responsible for controlling the aldol cyclizations of poly-β-ketone intermediates assembled during the catalytic cycle. Our ability to understand the high regioselective control that PT domains exert is hindered by the inaccessibility of intrinsically unstable poly-β-ketones for in vitro studies. We describe here the crystallographic application of "atom replacement" mimetics in which isoxazole rings linked by thioethers mimic the alternating sites of carbonyls in the poly-β-ketone intermediates...
May 8, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28482241/characterization-of-three-chalcone-synthase-like-genes-from-apple-malus-x-domestica-borkh
#8
Mosaab Yahyaa, Samah Ali, Rachel Davidovich-Rikanati, Muhammad Ibdah, Alona Shachtier, Yoram Eyal, Efraim Lewinsohn, Mwafaq Ibdah
Apple (Malus x domestica Brokh.) is a widely cultivated deciduous tree species of significant economic importance. Apple leaves accumulate high levels of flavonoids and dihydrochalcones, and their formation is dependent on enzymes of the chalcone synthase family. Three CHS genes were cloned from apple leaves and expressed in Escherichia coli. The encoded recombinant enzymes were purified and functionally characterized. In-vitro activity assays indicated that MdCHS1, MdCHS2 and MdCHS3 code for proteins exhibiting polyketide synthase activity that accepted either p-dihydrocoumaroyl-CoA, p-coumaroyl-CoA, or cinnamoyl-CoA as starter CoA substrates in the presence of malonyl-CoA, leading to production of phloretin, naringenin chalcone, and pinocembrin chalcone...
May 5, 2017: Phytochemistry
https://www.readbyqxmd.com/read/28475838/potent-nematicidal-activity-and-new-hybrid-metabolite-production-by-disruption-of-a-cytochrome-p450-gene-involved-in-the-biosynthesis-of-morphological-regulatory-arthrosporols-in-nematode-trapping-fungus-arthrobotrys-oligospora
#9
Tian-Yang Song, Zi-Fei Xu, Yong-Hong Chen, Qiu-Yan Ding, Yu-Rong Sun, Yang Miao, Ke-Qin Zhang, Xue-Mei Niu
Types of polyketide synthase-terpenoid synthase (PKS-TPS) hybrid metabolites, including arthrosporols with significant morphological regulatory activity, have been elucidated from nematode-trapping fungus Arthrobotrys oligospora. A previous study suggested that the gene cluster AOL_s00215 in A. oligospora was involved in the production of arthrosporols. Here, we report that disruption of one cytochrome P450 monooxygenase gene AOL_s00215g280 in the cluster resulted in significant phenotypic difference and much aerial hyphae...
May 15, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28471414/melanisation-of-aspergillus-terreus-is-butyrolactone-i-involved-in-the-regulation-of-both-dopa-and-dhn-types-of-pigments-in-submerged-culture
#10
Elina K Palonen, Sheetal Raina, Annika Brandt, Jussi Meriluoto, Tajalli Keshavarz, Juhani T Soini
Pigments and melanins of fungal spores have been investigated for decades, revealing important roles in the survival of the fungus in hostile environments. The key genes and the encoded enzymes for pigment and melanin biosynthesis have recently been found in Ascomycota, including Aspergillus spp. In Aspergillus terreus, the pigmentation has remained mysterious with only one class of melanin biogenesis being found. In this study, we examined an intriguing, partially annotated gene cluster of A. terreus strain NIH2624, utilizing previously sequenced transcriptome and improved gene expression data of strain MUCL 38669, under the influence of a suggested quorum sensing inducing metabolite, butyrolactone I...
May 4, 2017: Microorganisms
https://www.readbyqxmd.com/read/28465214/development-of-a-one-step-gene-knock-out-and-knock-in-method-for-metabolic-engineering-of-aureobasidium-pullulans
#11
Jian Guo, Yuanhua Wang, Baozhong Li, Siyao Huang, Yefu Chen, Xuewu Guo, Dongguang Xiao
Aureobasidium pullulans is an increasingly attractive host for bio-production of pullulan, heavy oil, polymalic acid, and a large spectrum of extracellular enzymes. To date, genetic manipulation of A. pullulans mainly relies on time-consuming conventional restriction enzyme digestion and ligation methods. In this study, we present a one-step homologous recombination-based method for rapid genetic manipulation in A. pullulans. Overlaps measuring >40bp length and 10μg DNA segments for homologous recombination provided maximum benefits to transformation of A...
April 29, 2017: Journal of Biotechnology
https://www.readbyqxmd.com/read/28464455/a-long-range-acting-dehydratase-domain-as-the-missing-link-for-c17-dehydration-in-iso-migrastatin-biosynthesis
#12
Ben Shen, Bo Zhang, Zhengren Xu, Qihui Teng, Guohui Pan, Ming Ma
The dehydratase domains (DHs) of the iso-migrastatin (iso-MGS) polyketide synthase (PKS) were investigated by systematic inactivation of the DHs in module-6, -9, -10 of MgsF (i.e., DH6, DH9, DH10) and module-11 of MgsG (i.e., DH11) in vivo, followed by structural characterization of the metabolites accumulated by the mutants, and biochemical characterization of DH10 in vitro, using polyketide substrate mimics with varying chain lengths. These studies allowed us to assign the functions for all four DHs, identifying DH10 as the dedicated dehydratase that catalyzes the dehydration of the C17 hydroxy group during iso-MGS biosynthesis...
May 2, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28463421/aromatic-polyketide-gtri-02-is-a-previously-unidentified-product-of-the-act-gene-cluster-in-streptomyces-coelicolor-a3-2
#13
Changsheng Wu, Koji Ichinose, Young Hae Choi, Gilles P van Wezel
The biosynthesis of aromatic polyketides derived from type II polyketide synthase (PKS) is complex, and it is not uncommon that highly similar gene clusters give rise to diverse structural architectures. The act biosynthetic gene cluster (BGC) of the model actinomycete Streptomyces coelicolor A3(2) is an archetypal type II PKS. Here, we show that the act BGC also specifies the aromatic polyketide GTRI-02 (1), and propose a mechanism for the biogenesis of its 3,4-dihydronaphthalen-1(2H)-one backbone. 1 was also produced by Streptomyces sp...
April 30, 2017: Chembiochem: a European Journal of Chemical Biology
https://www.readbyqxmd.com/read/28460065/sbspksv2-structure-based-sequence-analysis-of-polyketide-synthases-and-non-ribosomal-peptide-synthetases
#14
Shradha Khater, Money Gupta, Priyesh Agrawal, Neetu Sain, Jyoti Prava, Priya Gupta, Mansi Grover, Narendra Kumar, Debasisa Mohanty
Genome guided discovery of novel natural products has been a promising approach for identification of new bioactive compounds. SBSPKS web-server has been a valuable resource for analysis of polyketide synthase (PKS) and non-ribosomal peptide synthetase (NRPS) gene clusters. We have developed an updated version - SBSPKSv2 which is based on comprehensive analysis of sequence, structure and secondary metabolite chemical structure data from 311 experimentally characterized PKS/NRPS gene clusters with known biosynthetic products...
April 29, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/28460038/antismash-4-0-improvements-in-chemistry-prediction-and-gene-cluster-boundary-identification
#15
Kai Blin, Thomas Wolf, Marc G Chevrette, Xiaowen Lu, Christopher J Schwalen, Satria A Kautsar, Hernando G Suarez Duran, Emmanuel L C de Los Santos, Hyun Uk Kim, Mariana Nave, Jeroen S Dickschat, Douglas A Mitchell, Ekaterina Shelest, Rainer Breitling, Eriko Takano, Sang Yup Lee, Tilmann Weber, Marnix H Medema
Many antibiotics, chemotherapeutics, crop protection agents and food preservatives originate from molecules produced by bacteria, fungi or plants. In recent years, genome mining methodologies have been widely adopted to identify and characterize the biosynthetic gene clusters encoding the production of such compounds. Since 2011, the 'antibiotics and secondary metabolite analysis shell-antiSMASH' has assisted researchers in efficiently performing this, both as a web server and a standalone tool. Here, we present the thoroughly updated antiSMASH version 4, which adds several novel features, including prediction of gene cluster boundaries using the ClusterFinder method or the newly integrated CASSIS algorithm, improved substrate specificity prediction for non-ribosomal peptide synthetase adenylation domains based on the new SANDPUMA algorithm, improved predictions for terpene and ribosomally synthesized and post-translationally modified peptides cluster products, reporting of sequence similarity to proteins encoded in experimentally characterized gene clusters on a per-protein basis and a domain-level alignment tool for comparative analysis of trans-AT polyketide synthase assembly line architectures...
April 28, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/28453782/sempi-a-genome-based-secondary-metabolite-prediction-and-identification-web-server
#16
Paul F Zierep, Natàlia Padilla, Dimitar G Yonchev, Kiran K Telukunta, Dennis Klementz, Stefan Günther
The secondary metabolism of bacteria, fungi and plants yields a vast number of bioactive substances. The constantly increasing amount of published genomic data provides the opportunity for an efficient identification of gene clusters by genome mining. Conversely, for many natural products with resolved structures, the encoding gene clusters have not been identified yet. Even though genome mining tools have become significantly more efficient in the identification of biosynthetic gene clusters, structural elucidation of the actual secondary metabolite is still challenging, especially due to as yet unpredictable post-modifications...
April 27, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/28451290/activation-and-characterization-of-a-cryptic-gene-cluster-reveals-a-cyclization-cascade-for-polycyclic-tetramate-macrolactams
#17
Subhasish Saha, Wenjun Zhang, Guangtao Zhang, Yiguang Zhu, Yuchan Chen, Wei Liu, Chengshan Yuan, Qingbo Zhang, Haibo Zhang, Liping Zhang, Weimin Zhang, Changsheng Zhang
Polycyclic tetramate macrolactams (PTMs) are a growing class of natural products and are derived from a hybrid polyketide synthase (PKS)/non-ribosomal peptide synthetase (NRPS) pathway. PTM biosynthetic gene clusters are conserved and widely distributed in bacteria, however, most of them remain silent. Herein we report the activation of a PTM gene cluster in marine-derived Streptomyces pactum SCSIO 02999 by promoter engineering and heterologous expression, leading to the discovery of six new PTMs, pactamides A-F (11-16), with potent cytotoxic activity upon several human cancer cell lines...
February 1, 2017: Chemical Science
https://www.readbyqxmd.com/read/28451251/substrate-selectivity-of-an-isolated-enoyl-reductase-catalytic-domain-from-an-iterative-highly-reducing-fungal-polyketide-synthase-reveals-key-components-of-programming
#18
Douglas M Roberts, Christoph Bartel, Alan Scott, David Ivison, Thomas J Simpson, Russell J Cox
A cis-acting enoyl reductase (ER) catalytic domain was isolated from a fungal highly reducing iterative polyketide synthase (HR-iPKS) for the first time and studied in vitro. The ER from the squalestatin tetraketide synthase forms a discrete dimeric protein in solution. The ER shows broad substrate selectivity, reducing enoyl species including both natural and unnatural substrates. Pantetheine-bound substrate thiolesters reacted much faster than the corresponding SNAC thiolesters. The unnatural substrates included Z-olefins, 2-ethyl olefins and pentaketides...
February 1, 2017: Chemical Science
https://www.readbyqxmd.com/read/28451186/thioester-reduction-and-aldehyde-transamination-are-universal-steps-in-actinobacterial-polyketide-alkaloid-biosynthesis
#19
U R Awodi, J L Ronan, J Masschelein, E L C de Los Santos, G L Challis
Actinobacteria produce a variety of polyketide alkaloids with unusual structures. Recently, it was shown that a type I modular polyketide synthase (PKS) is involved in the assembly of coelimycin P1, a polyketide alkaloid produced by Streptomyces coelicolor M145. However, the mechanisms for converting the product of the PKS to coelimycin P1 remain to be elucidated. Here we show that the C-terminal thioester reductase (TR) domain of the PKS and an ω-transaminase are responsible for release of the polyketide chain as an aldehyde and its subsequent reductive amination...
January 1, 2017: Chemical Science
https://www.readbyqxmd.com/read/28450524/draft-genome-sequence-of-streptomyces-scabrisporus-nf3-an-endophyte-isolated-from-amphipterygium-adstringens
#20
Melissa Vazquez-Hernandez, Corina Diana Ceapa, Stefany Daniela Rodríguez-Luna, Romina Rodríguez-Sanoja, Sergio Sánchez
We report the draft genome sequence of Streptomyces scabrisporus NF3, an endophyte isolated from Amphipterygium adstringens in Chiapas, Mexico. This strain produces a new modified linaridin peptide. The genome harbors at least 50 gene clusters for synthases of polyketide and nonribosomal peptides, suggesting a prospective production of various secondary metabolites.
April 27, 2017: Genome Announcements
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