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Nature Chemical Biology

Jinru Zhang, Nicholas Liu, Ralph A Cacho, Zhou Gong, Zhu Liu, Wenming Qin, Chun Tang, Yi Tang, Jiahai Zhou
Nonribosomal peptide synthetases (NRPSs) in fungi biosynthesize important pharmaceutical compounds, including penicillin, cyclosporine and echinocandin. To understand the fungal strategy of forging the macrocyclic peptide linkage, we determined the crystal structures of the terminal condensation-like (CT) domain and the holo thiolation (T)-CT complex of Penicillium aethiopicum TqaA. The first, to our knowledge, structural depiction of the terminal module in a fungal NRPS provides a molecular blueprint for generating new macrocyclic peptide natural products...
October 17, 2016: Nature Chemical Biology
Avik Roy, Madhuchhanda Kundu, Malabendu Jana, Rama K Mishra, Yeni Yung, Chi-Hao Luan, Frank J Gonzalez, Kalipada Pahan
Peroxisome proliferator-activated receptor-α (PPARα) regulates hepatic fatty acid catabolism and mediates the metabolic response to starvation. Recently we found that PPARα is constitutively activated in nuclei of hippocampal neurons and controls plasticity via direct transcriptional activation of CREB. Here we report the discovery of three endogenous PPARα ligands-3-hydroxy-(2,2)-dimethyl butyrate, hexadecanamide, and 9-octadecenamide-in mouse brain hippocampus. Mass spectrometric detection of these compounds in mouse hippocampal nuclear extracts, in silico interaction studies, time-resolved FRET analyses, and thermal shift assay results clearly indicated that these three compounds served as ligands of PPARα...
October 17, 2016: Nature Chemical Biology
Björn Over, Pär Matsson, Christian Tyrchan, Per Artursson, Bradley C Doak, Michael A Foley, Constanze Hilgendorf, Stephen E Johnston, Maurice D Lee, Richard J Lewis, Patrick McCarren, Giovanni Muncipinto, Ulf Norinder, Matthew W D Perry, Jeremy R Duvall, Jan Kihlberg
Macrocycles are of increasing interest as chemical probes and drugs for intractable targets like protein-protein interactions, but the determinants of their cell permeability and oral absorption are poorly understood. To enable rational design of cell-permeable macrocycles, we generated an extensive data set under consistent experimental conditions for more than 200 non-peptidic, de novo-designed macrocycles from the Broad Institute's diversity-oriented screening collection. This revealed how specific functional groups, substituents and molecular properties impact cell permeability...
October 17, 2016: Nature Chemical Biology
John Chu, Xavier Vila-Farres, Daigo Inoyama, Melinda Ternei, Louis J Cohen, Emma A Gordon, Boojala Vijay B Reddy, Zachary Charlop-Powers, Henry A Zebroski, Ricardo Gallardo-Macias, Mark Jaskowski, Shruthi Satish, Steven Park, David S Perlin, Joel S Freundlich, Sean F Brady
Here we present a natural product discovery approach, whereby structures are bioinformatically predicted from primary sequence and produced by chemical synthesis (synthetic-bioinformatic natural products, syn-BNPs), circumventing the need for bacterial culture and gene expression. When we applied the approach to nonribosomal peptide synthetase gene clusters from human-associated bacteria, we identified the humimycins. These antibiotics inhibit lipid II flippase and potentiate β-lactam activity against methicillin-resistant Staphylococcus aureus in mice, potentially providing a new treatment regimen...
October 17, 2016: Nature Chemical Biology
Robert W Newberry, Ronald T Raines
Current limitations in de novo protein structure prediction and design suggest an incomplete understanding of the interactions that govern protein folding. Here we demonstrate that previously unappreciated hydrogen bonds occur within proteins between the amide proton and carbonyl oxygen of the same residue. Quantum calculations, infrared spectroscopy, and nuclear magnetic resonance spectroscopy show that these interactions share hallmark features of canonical hydrogen bonds. Biophysical analyses demonstrate that selective attenuation or enhancement of these C5 hydrogen bonds affects the stability of synthetic β-sheets...
October 17, 2016: Nature Chemical Biology
Gahl Levy, Naomi Habib, Maria Angela Guzzardi, Daniel Kitsberg, David Bomze, Elishai Ezra, Basak E Uygun, Korkut Uygun, Martin Trippler, Joerg F Schlaak, Oren Shibolet, Ella H Sklan, Merav Cohen, Joerg Timm, Nir Friedman, Yaakov Nahmias
Viruses lack the basic machinery needed to replicate and therefore must hijack the host's metabolism to propagate. Virus-induced metabolic changes have yet to be systematically studied in the context of host transcriptional regulation, and such studies shoul offer insight into host-pathogen metabolic interplay. In this work we identified hepatitis C virus (HCV)-responsive regulators by coupling system-wide metabolic-flux analysis with targeted perturbation of nuclear receptors in primary human hepatocytes. We found HCV-induced upregulation of glycolysis, ketogenesis and drug metabolism, with glycolysis controlled by activation of HNF4α, ketogenesis by PPARα and FXR, and drug metabolism by PXR...
October 10, 2016: Nature Chemical Biology
Orsolya Leidecker, Juan José Bonfiglio, Thomas Colby, Qi Zhang, Ilian Atanassov, Roko Zaja, Luca Palazzo, Anna Stockum, Ivan Ahel, Ivan Matic
ADP-ribosylation (ADPr) is a biologically and clinically important post-translational modification, but little is known about the amino acids it targets on cellular proteins. Here we present a proteomic approach for direct in vivo identification and quantification of ADPr sites on histones. We have identified 12 unique ADPr sites in human osteosarcoma cells and report serine ADPr as a new type of histone mark that responds to DNA damage.
October 10, 2016: Nature Chemical Biology
Paul G Leonard, Nikunj Satani, David Maxwell, Yu-Hsi Lin, Naima Hammoudi, Zhenghong Peng, Federica Pisaneschi, Todd M Link, Gilbert R Lee, Duoli Sun, Basvoju A Bhanu Prasad, Maria Emilia Di Francesco, Barbara Czako, John M Asara, Y Alan Wang, William Bornmann, Ronald A DePinho, Florian L Muller
Despite being crucial for energy generation in most forms of life, few if any microbial antibiotics specifically inhibit glycolysis. To develop a specific inhibitor of the glycolytic enzyme enolase 2 (ENO2) for the treatment of cancers with deletion of ENO1 (encoding enolase 1), we modeled the synthetic tool compound inhibitor phosphonoacetohydroxamate (PhAH) into the active site of human ENO2. A ring-stabilized analog of PhAH, in which the hydroxamic nitrogen is linked to Cα by an ethylene bridge, was predicted to increase binding affinity by stabilizing the inhibitor in a bound conformation...
October 10, 2016: Nature Chemical Biology
Jenny Z Zhang, Katarzyna P Sokol, Nicholas Paul, Elisabet Romero, Rienk van Grondelle, Erwin Reisner
The integration of the water-oxidation enzyme photosystem II (PSII) into electrodes allows the electrons extracted from water oxidation to be harnessed for enzyme characterization and to drive novel endergonic reactions. However, PSII continues to underperform in integrated photoelectrochemical systems despite extensive optimization efforts. Here we carried out protein-film photoelectrochemistry using spinach and Thermosynechococcus elongatus PSII, and we identified a competing charge transfer pathway at the enzyme-electrode interface that short-circuits the known water-oxidation pathway...
October 10, 2016: Nature Chemical Biology
Fuun Kawano, Risako Okazaki, Masayuki Yazawa, Moritoshi Sato
Genome engineering techniques represented by the Cre-loxP recombination system have been used extensively for biomedical research. However, powerful and useful techniques for genome engineering that have high spatiotemporal precision remain elusive. Here we develop a highly efficient photoactivatable Cre recombinase (PA-Cre) to optogenetically control genome engineering in vivo. PA-Cre is based on the reassembly of split Cre fragments by light-inducible dimerization of the Magnet system. PA-Cre enables sharp induction (up to 320-fold) of DNA recombination and is efficiently activated even by low-intensity illumination (∼0...
October 10, 2016: Nature Chemical Biology
Zhewang Lin, Min Dong, Yugang Zhang, Eunyoung Alisa Lee, Hening Lin
Diphthamide and the tRNA wobble uridine modifications both require diphthamide biosynthesis 3 (Dph3) protein as an electron donor for the iron-sulfur clusters in their biosynthetic enzymes. Here, using a proteomic approach, we identified Saccharomyces cerevisiae cytochrome b5 reductase (Cbr1) as a NADH-dependent reductase for Dph3. The NADH- and Cbr1-dependent reduction of Dph3 may provide a regulatory linkage between cellular metabolic state and protein translation.
October 3, 2016: Nature Chemical Biology
Cecilia Lopez-Sambrooks, Shiteshu Shrimal, Carol Khodier, Daniel P Flaherty, Natalie Rinis, Jonathan C Charest, Ningguo Gao, Peng Zhao, Lance Wells, Timothy A Lewis, Mark A Lehrman, Reid Gilmore, Jennifer E Golden, Joseph N Contessa
Asparagine (N)-linked glycosylation is a protein modification critical for glycoprotein folding, stability, and cellular localization. To identify small molecules that inhibit new targets in this biosynthetic pathway, we initiated a cell-based high-throughput screen and lead-compound-optimization campaign that delivered a cell-permeable inhibitor, NGI-1. NGI-1 targets oligosaccharyltransferase (OST), a hetero-oligomeric enzyme that exists in multiple isoforms and transfers oligosaccharides to recipient proteins...
October 3, 2016: Nature Chemical Biology
Chris A Dejong, Gregory M Chen, Haoxin Li, Chad W Johnston, Mclean R Edwards, Philip N Rees, Michael A Skinnider, Andrew L H Webster, Nathan A Magarvey
Polyketides (PKs) and nonribosomal peptides (NRPs) are profoundly important natural products, forming the foundations of many therapeutic regimes. Decades of research have revealed over 11,000 PK and NRP structures, and genome sequencing is uncovering new PK and NRP gene clusters at an unprecedented rate. However, only ∼10% of PK and NRPs are currently associated with gene clusters, and it is unclear how many of these orphan gene clusters encode previously isolated molecules. Therefore, to efficiently guide the discovery of new molecules, we must first systematically de-orphan emergent gene clusters from genomes...
October 3, 2016: Nature Chemical Biology
Hans J Genee, Anne P Bali, Søren D Petersen, Solvej Siedler, Mads T Bonde, Luisa S Gronenberg, Mette Kristensen, Scott J Harrison, Morten O A Sommer
Only 25% of bacterial membrane transporters have functional annotation owing to the difficulty of experimental study and of accurate prediction of their function. Here we report a sequence-independent method for high-throughput mining of novel transporters. The method is based on ligand-responsive biosensor systems that enable selective growth of cells only if they encode a ligand-specific importer. We developed such a synthetic selection system for thiamine pyrophosphate and mined soil and gut metagenomes for thiamine-uptake functions...
October 3, 2016: Nature Chemical Biology
Sibel Kalyoncu, David P Heaner, Zohre Kurt, Casey M Bethel, Chiamaka U Ukachukwu, Srinivas Chakravarthy, Jim C Spain, Raquel L Lieberman
Nitroaromatic compounds are typically toxic and resistant to degradation. Bradyrhizobium species strain JS329 metabolizes 5-nitroanthranilic acid (5NAA), which is a molecule secreted by Streptomyces scabies, the plant pathogen responsible for potato scab. The first biodegradation enzyme is 5NAA-aminohydrolase (5NAA-A), a metalloprotease family member that converts 5NAA to 5-nitrosalicylic acid. We characterized 5NAA-A biochemically and obtained snapshots of its mechanism. 5NAA-A, an octamer that can use several divalent transition metals for catalysis in vitro, employs a nucleophilic aromatic substitution mechanism...
October 3, 2016: Nature Chemical Biology
Isabelle Becher, Thilo Werner, Carola Doce, Esther A Zaal, Ina Tögel, Crystal A Khan, Anne Rueger, Marcel Muelbaier, Elsa Salzer, Celia R Berkers, Paul F Fitzpatrick, Marcus Bantscheff, Mikhail M Savitski
We describe a two-dimensional thermal proteome profiling strategy that can be combined with an orthogonal chemoproteomics approach to enable comprehensive target profiling of the marketed histone deacetylase inhibitor panobinostat. The N-hydroxycinnamide moiety is identified as critical for potent and tetrahydrobiopterin-competitive inhibition of phenylalanine hydroxylase leading to increases in phenylalanine and decreases in tyrosine levels. These findings provide a rationale for adverse clinical observations and suggest repurposing of the drug for treatment of tyrosinemia...
September 26, 2016: Nature Chemical Biology
Amy E Palmer, Jin Zhang
No abstract text is available yet for this article.
September 26, 2016: Nature Chemical Biology
Kunhua Li, Heather L Condurso, Gengnan Li, Yousong Ding, Steven D Bruner
Macrocyclization is a common feature of natural product biosynthetic pathways including the diverse family of ribosomal peptides. Microviridins are architecturally complex cyanobacterial ribosomal peptides that target proteases with potent reversible inhibition. The product structure is constructed via three macrocyclizations catalyzed sequentially by two members of the ATP-grasp family, a unique strategy for ribosomal peptide macrocyclization. Here we describe in detail the structural basis for the enzyme-catalyzed macrocyclizations in the microviridin J pathway of Microcystis aeruginosa...
September 26, 2016: Nature Chemical Biology
Edward A Lilla, Kenichi Yokoyama
Nikkomycins and polyoxins are antifungal peptidylnucleoside antibiotics active against human and plant pathogens. Here we report that during peptidylnucleoside biosynthesis in Streptomyces cacaoi and S. tendae, the C5' extension of the nucleoside essential for downstream structural diversification is catalyzed by a conserved radical S-adenosyl-L-methionine (SAM) enzyme, PolH or NikJ. This is distinct from the nucleophilic mechanism reported for antibacterial nucleosides and represents a new mechanism of nucleoside natural product biosynthesis...
November 2016: Nature Chemical Biology
Mette L Skjoedt, Tim Snoek, Kanchana R Kildegaard, Dushica Arsovska, Michael Eichenberger, Tobias J Goedecke, Arun S Rajkumar, Jie Zhang, Mette Kristensen, Beata J Lehka, Solvej Siedler, Irina Borodina, Michael K Jensen, Jay D Keasling
Whole-cell biocatalysts have proven a tractable path toward sustainable production of bulk and fine chemicals. Yet the screening of libraries of cellular designs to identify best-performing biocatalysts is most often a low-throughput endeavor. For this reason, the development of biosensors enabling real-time monitoring of production has attracted attention. Here we applied systematic engineering of multiple parameters to search for a general biosensor design in the budding yeast Saccharomyces cerevisiae based on small-molecule binding transcriptional activators from the prokaryote superfamily of LysR-type transcriptional regulators (LTTRs)...
November 2016: Nature Chemical Biology
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