1
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Kahlert L, Lichstrahl MS, Townsend CA. Colorimetric Determination of Adenylation Domain Activity in Nonribosomal Peptide Synthetases by Using Chrome Azurol S. Chembiochem 2023; 24:e202200668. [PMID: 36511946 PMCID: PMC10041650 DOI: 10.1002/cbic.202200668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 12/12/2022] [Accepted: 12/13/2022] [Indexed: 12/15/2022]
Abstract
Adenylation domains are the main contributor to structural complexity among nonribosomal peptides due to their varied but stringent substrate selection. Several in vitro assays to determine the substrate specificity of these dedicated biocatalysts have been implemented, but high sensitivity is often accompanied by the cost of laborious procedures, expensive reagents or the requirement for auxiliary enzymes. Here, we describe a simple protocol that is based on the removal of ferric iron from a preformed chromogenic complex between ferric iron and Chrome Azurol S. Adenylation activity can be rapidly followed by a decrease in absorbance at 630 nm, visualized by a prominent color change from blue to orange.
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Affiliation(s)
- Lukas Kahlert
- Department of Chemistry, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland, 21218, USA
| | - Michael S Lichstrahl
- Department of Chemistry, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland, 21218, USA
| | - Craig A Townsend
- Department of Chemistry, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland, 21218, USA
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2
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Patel KD, Ahmed SF, MacDonald MR, Gulick AM. Structural Studies of Modular Nonribosomal Peptide Synthetases. Methods Mol Biol 2023; 2670:17-46. [PMID: 37184698 DOI: 10.1007/978-1-0716-3214-7_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The non-ribosomal peptide synthetases (NRPSs) are a family of modular enzymes involved in the production of peptide natural products. Not restricted by the constraints of ribosomal peptide and protein production, the NRPSs are able to incorporate unusual amino acids and other suitable building blocks into the final product. The NRPSs operate with an assembly line strategy in which peptide intermediates are covalently tethered to a peptidyl carrier protein and transported to different catalytic domains for the multiple steps in the biosynthesis. Often the carrier and catalytic domains are joined into a single large multidomain protein. This chapter serves to introduce the NRPS enzymes, using the nocardicin NRPS system as an example that highlights many common features to NRPS biochemistry. We then describe recent advances in the structural biology of NRPSs focusing on large multidomain structures that have been determined.
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Affiliation(s)
- Ketan D Patel
- Department of Structural Biology, University at Buffalo, SUNY, Buffalo, NY, USA
| | - Syed Fardin Ahmed
- Department of Structural Biology, University at Buffalo, SUNY, Buffalo, NY, USA
| | - Monica R MacDonald
- Department of Structural Biology, University at Buffalo, SUNY, Buffalo, NY, USA
| | - Andrew M Gulick
- Department of Structural Biology, University at Buffalo, SUNY, Buffalo, NY, USA.
- Department of Structural Biology, Jacobs School of Medicine & Biomedical Sciences, Buffalo, NY, USA.
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3
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Wang P, Zhang X, Tao Y, Lv X, Cheng S, Liu C. Improved l-phenylglycine synthesis by introducing an engineered cofactor self-sufficient system. Synth Syst Biotechnol 2022; 7:513-521. [PMID: 35024478 PMCID: PMC8715069 DOI: 10.1016/j.synbio.2021.12.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 11/18/2021] [Accepted: 12/16/2021] [Indexed: 11/09/2022] Open
Abstract
l-phenylglycine (L-phg) is a valuable non-proteinogenic amino acid used as a precursor to β-lactam antibiotics, antitumor agent taxol and many other pharmaceuticals. L-phg synthesis through microbial bioconversion allows for high enantioselectivity and sustainable production, which will be of great commercial and environmental value compared with organic synthesis methods. In this work, an L-phg synthesis pathway was built in Escherichia coli resulting in 0.23 mM L-phg production from 10 mM l-phenylalanine. Then, new hydroxymandelate synthases and hydroxymandelate oxidases were applied in the L-phg synthesis leading to a 5-fold increase in L-phg production. To address 2-oxoglutarate, NH4 +, and NADH shortage, a cofactor self-sufficient system was introduced, which converted by-product l-glutamate and NAD+ to these three cofactors simultaneously. In this way, L-phg increased 2.5-fold to 2.82 mM. Additionally, in order to reduce the loss of these three cofactors, a protein scaffold between synthesis pathway and cofactor regeneration modular was built, which further improved the L-phg production to 3.72 mM with a yield of 0.34 g/g L-phe. This work illustrated a strategy applying for whole-cell biocatalyst converting amino acid to its value-added chiral amine in a cofactor self-sufficient manner.
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Affiliation(s)
- Pengchao Wang
- School of Life Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, PR China
- Key Laboratory for Enzymes and Enzyme-like Material Engineering of Heilongjiang, PR China
| | - Xiwen Zhang
- School of Life Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, PR China
| | - Yucheng Tao
- School of Life Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, PR China
| | - Xubing Lv
- School of Life Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, PR China
| | - Shengjie Cheng
- School of Life Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, PR China
| | - Chengwei Liu
- School of Life Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, PR China
- Key Laboratory for Enzymes and Enzyme-like Material Engineering of Heilongjiang, PR China
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4
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Hernández VM, Arteaga A, Dunn MF. Diversity, properties and functions of bacterial arginases. FEMS Microbiol Rev 2021; 45:6308370. [PMID: 34160574 DOI: 10.1093/femsre/fuab034] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 06/17/2021] [Indexed: 02/07/2023] Open
Abstract
The metalloenzyme arginase hydrolyzes L-arginine to produce L-ornithine and urea. In bacteria, arginase has important functions in basic nitrogen metabolism and redistribution, production of the key metabolic precursor L-ornithine, stress resistance and pathogenesis. We describe the regulation and specific functions of the arginase pathway as well as summarize key characteristics of related arginine catabolic pathways. The use of arginase-derived ornithine as a precursor molecule is reviewed. We discuss the biochemical and transcriptional regulation of arginine metabolism, including arginase, with the latter topic focusing on the RocR and AhrC transcriptional regulators in the model organism Bacillus subtilis. Finally, we consider similarities and contrasts in the structure and catalytic mechanism of the arginases from Bacillus caldovelox and Helicobacter pylori. The overall aim of this review is to provide a panorama of the diversity of physiological functions, regulation, and biochemical features of arginases in a variety of bacterial species.
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Affiliation(s)
- Victor M Hernández
- Programa de Genómica Funcional de Procariotes, Centro de Ciencias Genómicas-Universidad Nacional Autonoma de México, Cuernavaca, Morelos, C.P. 62210, Mexico
| | - Alejandra Arteaga
- Programa de Genómica Funcional de Procariotes, Centro de Ciencias Genómicas-Universidad Nacional Autonoma de México, Cuernavaca, Morelos, C.P. 62210, Mexico
| | - Michael F Dunn
- Programa de Genómica Funcional de Procariotes, Centro de Ciencias Genómicas-Universidad Nacional Autonoma de México, Cuernavaca, Morelos, C.P. 62210, Mexico
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5
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Engelbrecht A, Saad H, Gross H, Kaysser L. Natural Products from Nocardia and Their Role in Pathogenicity. Microb Physiol 2021; 31:217-232. [PMID: 34139700 DOI: 10.1159/000516864] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 04/26/2021] [Indexed: 11/19/2022]
Abstract
Nocardia spp. are filamentous Actinobacteria of the order Corynebacteriales and mostly known for their ability to cause localized and systemic infections in humans. However, the onset and progression of nocardiosis is only poorly understood, in particular the mechanisms of strain-specific presentations. Recent genome sequencing has revealed an extraordinary capacity for the production of specialized small molecules. Such secondary metabolites are often crucial for the producing microbe to survive the challenges of different environmental conditions. An interesting question thus concerns the role of these natural products in Nocardia-associated pathogenicity and immune evasion in a human host. In this review, a summary and discussion of Nocardia metabolites is presented, which may play a part in nocardiosis because of their cytotoxic, immunosuppressive and metal-chelating properties or otherwise vitally important functions. This review also contains so far unpublished data concerning the biosynthesis of these molecules that were obtained by detailed bioinformatic analyses.
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Affiliation(s)
- Alicia Engelbrecht
- Department of Pharmaceutical Biology, University of Tübingen, Tübingen, Germany
| | - Hamada Saad
- Department of Pharmaceutical Biology, University of Tübingen, Tübingen, Germany.,Department of Phytochemistry and Plant Systematics, Division of Pharmaceutical Industries, National Research Centre, Cairo, Egypt
| | - Harald Gross
- Department of Pharmaceutical Biology, University of Tübingen, Tübingen, Germany
| | - Leonard Kaysser
- Department of Pharmaceutical Biology, University of Tübingen, Tübingen, Germany.,Institute for Drug Discovery, University of Leipzig, Leipzig, Germany
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6
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Long DH, Townsend CA. Acyl Donor Stringency and Dehydroaminoacyl Intermediates in β-Lactam Formation by a Non-ribosomal Peptide Synthetase. ACS Chem Biol 2021; 16:806-812. [PMID: 33847484 DOI: 10.1021/acschembio.1c00117] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Condensation (C) domains in non-ribosomal peptide synthetases catalyze peptide elongation steps whereby activated amino acid or peptidyl acyl donors are coupled with specific amino acid acceptors. In the biosynthesis of the β-lactam antibiotic nocardicin A, an unusual C domain converts a seryl tetrapeptide into its pentapeptide product containing an integrated β-lactam ring. While indirect evidence for the intermediacy of a dehydroalanyl species has been reported, here we describe observation of the elusive enzyme-bound dehydroamino acyl intermediate generated from the corresponding allo-threonyl tetrapeptide and partitioned into pentapeptide products containing either a dehydrobutyrine residue or an embedded β-lactam. Contrary to trends in the literature where condensation domains have been deemed flexible as to acyl donor structure, this β-lactam synthesizing domain is highly discriminating. The observation of dehydrobutyrine formation links this C domain to related clades associated with natural products containing dehydroamino acid and d-configured residues, suggesting a common mechanistic link.
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Affiliation(s)
- Darcie H. Long
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Craig A. Townsend
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
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7
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Dekimpe S, Masschelein J. Beyond peptide bond formation: the versatile role of condensation domains in natural product biosynthesis. Nat Prod Rep 2021; 38:1910-1937. [DOI: 10.1039/d0np00098a] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Condensation domains perform highly diverse functions during natural product biosynthesis and are capable of generating remarkable chemical diversity.
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Affiliation(s)
- Sofie Dekimpe
- Laboratory for Biomolecular Discovery & Engineering
- Department of Biology
- KU Leuven
- Leuven
- Belgium
| | - Joleen Masschelein
- Laboratory for Biomolecular Discovery & Engineering
- Department of Biology
- KU Leuven
- Leuven
- Belgium
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8
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Zhang D, Wang X, Ye Y, He Y, He F, Tian Y, Luo Y, Liang S. Label-free proteomic dissection on dptP-deletion mutant uncovers dptP involvement in strain growth and daptomycin tolerance of Streptomyces roseosporus. Microb Biotechnol 2020; 14:708-725. [PMID: 33369164 PMCID: PMC7936300 DOI: 10.1111/1751-7915.13736] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Accepted: 12/07/2020] [Indexed: 02/05/2023] Open
Abstract
Daptomycin (DAP) is a novel microbial lipopeptide antibiotic synthesized by the DAP biosynthetic gene cluster dpt of Streptomyces roseosporus (S. roseosporus). DptP gene locates upstream of dpt and confers DAP resistance to Streptomyces ambofaciens (S. ambofaciens). So far, the biological functions of dptP gene for S. roseosporus growth are still completely uncovered. We performed label‐free quantification proteomic dissections with loss‐ and gain‐of‐function experiments to decipher dptP‐involved functions. Deletion of dptP gene activated energy metabolism and metabolism of secondary metabolites pathways and enhanced the transcription levels and protein abundance of key members of the dpt cluster. Whereas dptP deletion inhibited transport/signal transduction and drug resistance pathways and protein abundance of cell division‐relative proteins, subsequently decreased mycelia cell growth rate. S. roseosporus strain with dptP deletion was more sensitive to DAP treatment compared to the wild type. In contrast, overexpression of dptP gene decreased transcription levels of DAP biosynthetic genes and enhanced growth rate of Streptomcyes strain upon elevated culture temperature and DAP supplementation. Taken together, dptP gene contributes to Streptomcyes primary growth under elevated temperature and DAP treatment, whereas it plays negative roles on metabolism of secondary metabolites and transcription of DAP biosynthetic genes.
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Affiliation(s)
- Dan Zhang
- State Key Laboratory of Biotherapy and Cancer Center, Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Xixi Wang
- State Key Laboratory of Biotherapy and Cancer Center, Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Yang Ye
- State Key Laboratory of Biotherapy and Cancer Center, Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Yu He
- State Key Laboratory of Biotherapy and Cancer Center, Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Fuqiang He
- State Key Laboratory of Biotherapy and Cancer Center, Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Yongqiang Tian
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education and College of Light Industry, Textile and Food Engineering, Sichuan University, Chengdu, 610065, China
| | - Yunzi Luo
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Shufang Liang
- State Key Laboratory of Biotherapy and Cancer Center, Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu, 610041, China
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9
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Li Y, Tahlan K, Bignell DR. Functional Cross-Talk of MbtH-Like Proteins During Thaxtomin Biosynthesis in the Potato Common Scab Pathogen Streptomyces scabiei. Front Microbiol 2020; 11:585456. [PMID: 33178168 PMCID: PMC7593251 DOI: 10.3389/fmicb.2020.585456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 09/23/2020] [Indexed: 11/13/2022] Open
Abstract
Thaxtomin A is a potent phytotoxin that serves as the principle pathogenicity determinant of the common scab pathogen, Streptomyces scabiei, and is also a promising natural herbicide for agricultural applications. The biosynthesis of thaxtomin A involves the non-ribosomal peptide synthetases (NRPSs) TxtA and TxtB, and an MbtH-like protein (MLP), TxtH, which may function as a chaperone by promoting the proper folding of the two NRPS enzymes in S. scabiei. MLPs are required for the proper function of many NRPS enzymes in bacteria, and they are often capable of interacting with NRPSs from different biosynthetic pathways, though the mechanism by which this occurs is still poorly understood. To gain additional insights into MLP functional cross-talk, we conducted a broad survey of MLPs from diverse phylogenetic lineages to determine if they could functionally replace TxtH. The MLPs were assessed using a protein solubility assay to determine whether they could promote the soluble expression of the TxtA and TxtB adenylation domains. In addition, the MLPs were tested for their ability to restore thaxtomin production in a S. scabiei mutant that lacked TxtH and other endogenous MLPs. Our results showed that the MLPs investigated vary in their ability to exhibit functional cross-talk with TxtH, with two of the MLPs being unable to compensate for the loss of TxtH in the assays performed. The ability of an MLP to serve as a functional partner for the thaxtomin NRPS was not correlated with its overall amino acid similarity with TxtH, but instead with the presence of highly conserved residues. In silico structural analysis of TxtH in association with the TxtA and TxtB adenylation domains revealed that several such residues are situated at the predicted interaction interface, suggesting that they might be critical for promoting functional interactions between MLPs and the thaxtomin NRPS enzymes. Overall, our study provides additional insights into the mechanism of MLP cross-talk, and it enhances our understanding of the thaxtomin biosynthetic machinery. It is anticipated that our findings will have useful applications for both the control of common scab disease and the commercial production of thaxtomin A for agricultural use.
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10
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Bernhardt M, Berman S, Zechel D, Bechthold A. Role of Two Exceptional trans Adenylation Domains and MbtH-like Proteins in the Biosynthesis of the Nonribosomal Peptide WS9324A from Streptomyces calvus ATCC 13382. Chembiochem 2020; 21:2659-2666. [PMID: 32333627 PMCID: PMC7539972 DOI: 10.1002/cbic.202000142] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 04/24/2020] [Indexed: 11/26/2022]
Abstract
Nonribosomal peptide synthetases (NRPS) are organized in a modular arrangement. Usually, the modular order corresponds to the assembly of the amino acids in the respective peptide, following the collinearity rule. The WS9326A biosynthetic gene cluster from Streptomyces calvus shows deviations from this rule. Most interesting is the presence of two trans adenylation domains that are located downstream of the modular NRPS arrangement. Adenylation domains are responsible for the activation of their respective amino acids. In this study, we confirmed the involvement of the trans adenylation domains in WS9326A biosynthesis by performing gene knockout experiments and by observing the selective adenylation of their predicted amino acid substrates in vitro. We conclude that the trans adenylation domains are essential for WS9326A biosynthesis. Moreover, both adenylation domains are observed to have MbtH‐like protein dependency. Overall, we conclude that the trans adenylation domains are essential for WS9326A biosynthesis.
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Affiliation(s)
- Mirjam Bernhardt
- Department of Pharmaceutical Biology and Biotechnology, University of Freiburg, Stefan-Meier-Strass 19, 79104, Freiburg im Breisgau, Germany
| | - Stefanie Berman
- Department of Pharmaceutical Biology and Biotechnology, University of Freiburg, Stefan-Meier-Strass 19, 79104, Freiburg im Breisgau, Germany
| | - David Zechel
- Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, Ontario, K7 L 3 N6, Canada
| | - Andreas Bechthold
- Department of Pharmaceutical Biology and Biotechnology, University of Freiburg, Stefan-Meier-Strass 19, 79104, Freiburg im Breisgau, Germany
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11
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Mori S, Garneau-Tsodikova S, Tsodikov OV. Unimodular Methylation by Adenylation-Thiolation Domains Containing an Embedded Methyltransferase. J Mol Biol 2020; 432:5802-5808. [PMID: 32920052 DOI: 10.1016/j.jmb.2020.09.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 08/16/2020] [Accepted: 09/03/2020] [Indexed: 10/23/2022]
Abstract
Nonribosomal peptides (NRPs) are natural products that are biosynthesized by large multi-enzyme assembly lines called nonribosomal peptide synthetases (NRPSs). We have previously discovered that backbone or side chain methylation of NRP residues is carried out by an interrupted adenylation (A) domain that contains an internal methyltransferase (M) domain, while maintaining a monolithic AMA fold of the bifunctional enzyme. A key question that has remained unanswered is at which step of the assembly line mechanism the methylation by these embedded M domains takes place. Does the M domain methylate an amino acid residue tethered to a thiolation (T) domain on same NRPS module (in cis), or does it methylate this residue on a nascent peptide tethered to a T domain on another module (in trans)? In this study, we investigated the kinetics of methylation by wild-type AMAT tridomains from two NRPSs involved in biosynthesis of anticancer depsipeptides thiocoraline and echinomycin, and by mutants of these domains, for which methylation can occur only in trans. The analysis of the methylation kinetics unequivocally demonstrated that the wild-type AMATs methylate overwhelmingly in cis, strongly suggesting that this is also the case in the context of the entire NRPS assembly line process. The mechanistic insight gained in this study will facilitate rational genetic engineering of NRPS to generate unnaturally methylated NRPs.
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Affiliation(s)
- Shogo Mori
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596, USA
| | - Sylvie Garneau-Tsodikova
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596, USA.
| | - Oleg V Tsodikov
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596, USA.
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12
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Zhu C, Xie J, Li Y, Xu W. Direct Deoxygenative Intramolecular Acylation of Biarylcarboxylic Acids. Synlett 2020. [DOI: 10.1055/s-0040-1707246] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
A photocatalyzed intramolecular cyclization is developed for the synthesis of fluorenones. In this photoredox reaction, triphenylphosphine is used as an inexpensive and effective deoxygenative reagent for biarylcarboxylic acids to give acyl radicals, which quickly undergo intramolecular radical cyclization. Reactions in the presence of air and continuous flow photoredox technology demonstrate the generality and practicality of this process.
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Affiliation(s)
- Chengjian Zhu
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry
| | - Jin Xie
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University
| | - Yantao Li
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University
| | - Wentao Xu
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University
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13
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Kaniusaite M, Tailhades J, Kittilä T, Fage CD, Goode RJA, Schittenhelm RB, Cryle MJ. Understanding the early stages of peptide formation during the biosynthesis of teicoplanin and related glycopeptide antibiotics. FEBS J 2020; 288:507-529. [PMID: 32359003 DOI: 10.1111/febs.15350] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 04/20/2020] [Accepted: 04/28/2020] [Indexed: 02/02/2023]
Abstract
The biosynthesis of the glycopeptide antibiotics (GPAs) demonstrates the exceptional ability of nonribosomal peptide (NRP) synthesis to generate diverse and complex structures from an expanded array of amino acid precursors. Whilst the heptapeptide cores of GPAs share a conserved C terminus, including the aromatic residues involved cross-linking and that are essential for the antibiotic activity of GPAs, most structural diversity is found within the N terminus of the peptide. Furthermore, the origin of the (D)-stereochemistry of residue 1 of all GPAs is currently unclear, despite its importance for antibiotic activity. Given these important features, we have now reconstituted modules (M) 1-4 of the NRP synthetase (NRPS) assembly lines that synthesise the clinically relevant type IV GPA teicoplanin and the related compound A40926. Our results show that important roles in amino acid modification during the NRPS-mediated biosynthesis of GPAs can be ascribed to the actions of condensation domains present within these modules, including the incorporation of (D)-amino acids at position 1 of the peptide. Our results also indicate that hybrid NRPS assembly lines can be generated in a facile manner by mixing NRPS proteins from different systems and that uncoupling of peptide formation due to different rates of activity seen for NRPS modules can be controlled by varying the ratio of NRPS modules. Taken together, this indicates that NRPS assembly lines function as dynamic peptide assembly lines and not static megaenzyme complexes, which has significant implications for biosynthetic redesign of these important biosynthetic systems.
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Affiliation(s)
- Milda Kaniusaite
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University, Clayton, Australia.,EMBL Australia, Monash University, Clayton, Australia.,ARC Centre of Excellence for Innovations in Peptide and Protein Science, Monash University, Clayton, Australia
| | - Julien Tailhades
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University, Clayton, Australia.,EMBL Australia, Monash University, Clayton, Australia.,ARC Centre of Excellence for Innovations in Peptide and Protein Science, Monash University, Clayton, Australia
| | - Tiia Kittilä
- Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Heidelberg, Germany
| | | | - Robert J A Goode
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University, Clayton, Australia.,Monash Proteomics and Metabolomics Facility, Monash University, Clayton, Australia
| | - Ralf B Schittenhelm
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University, Clayton, Australia.,Monash Proteomics and Metabolomics Facility, Monash University, Clayton, Australia
| | - Max J Cryle
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University, Clayton, Australia.,EMBL Australia, Monash University, Clayton, Australia.,ARC Centre of Excellence for Innovations in Peptide and Protein Science, Monash University, Clayton, Australia
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14
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Lundy TA, Mori S, Thamban Chandrika N, Garneau-Tsodikova S. Characterization of a Unique Interrupted Adenylation Domain That Can Catalyze Three Reactions. ACS Chem Biol 2020; 15:282-289. [PMID: 31887013 DOI: 10.1021/acschembio.9b00929] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Interrupted adenylation (A) domains contain auxiliary domains within their structure and are a subject of growing interest in the field of nonribosomal peptide biosynthesis. They have been shown to possess intriguing functions and structure as well as promising engineering potential. Here, we present the characterization of an unprecedented type of interrupted A domain from the columbamides biosynthetic pathway, ColG(AMsMbA). This interrupted A domain contains two back-to-back methylation (M) domains within the same interruption site in the A domain, whereas previously, naturally occurring reported and characterized interrupted A domains harbored only one M domain. By a series of radiometric and mass spectrometry assays, we show that the first and second M domains site specifically methylate the side-chain oxygen and backbone nitrogen of l-Ser after the substrate is transferred onto a carrier thiolation domain, ColG(T). This is the first reported characterization of a dimethylating back-to-back interrupted A domain. The insights gained by this work lay the foundation for future combinatorial biosynthesis of site specifically methylated nonribosomal peptides.
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Affiliation(s)
- Taylor A. Lundy
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536-0596, United States
| | - Shogo Mori
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536-0596, United States
| | - Nishad Thamban Chandrika
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536-0596, United States
| | - Sylvie Garneau-Tsodikova
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536-0596, United States
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15
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Structure of a bound peptide phosphonate reveals the mechanism of nocardicin bifunctional thioesterase epimerase-hydrolase half-reactions. Nat Commun 2019; 10:3868. [PMID: 31455765 PMCID: PMC6711958 DOI: 10.1038/s41467-019-11740-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Accepted: 08/02/2019] [Indexed: 12/19/2022] Open
Abstract
Nonribosomal peptide synthetases (NRPSs) underlie the biosynthesis of many natural products that have important medicinal utility. Protection of the NRPS peptide products from proteolysis is critical to these pathways and is often achieved by structural modification, principally the introduction of d-amino acid residues into the elongating peptide. These amino acids are generally formed in situ from their l-stereoisomers by epimerization domains or dual-function condensation/epimerization domains. In singular contrast, the thioesterase domain of nocardicin biosynthesis mediates both the effectively complete l- to d-epimerization of its C-terminal amino acid residue (≥100:1) and hydrolytic product release. We report herein high-resolution crystal structures of the nocardicin thioesterase domain in ligand-free form and reacted with a structurally precise fluorophosphonate substrate mimic that identify the complete peptide binding pocket to accommodate both stereoisomers. These structures combined with additional functional studies provide detailed mechanistic insight into this unique dual-function NRPS domain. NocTE is a nonribosomal peptide synthetase thioesterase that completes the biosynthesis of pro-nocardicin G, the precursor for nocardicin β-lactam antibiotics. Here the authors provide mechanistic insights into NocTE by determining its crystal structures in the ligand-free form and covalently linked to a fluorophosphonate substrate mimic.
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16
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The structural basis of N-acyl-α-amino-β-lactone formation catalyzed by a nonribosomal peptide synthetase. Nat Commun 2019; 10:3432. [PMID: 31366889 PMCID: PMC6668435 DOI: 10.1038/s41467-019-11383-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 07/11/2019] [Indexed: 01/19/2023] Open
Abstract
Nonribosomal peptide synthetases produce diverse natural products using a multidomain architecture where the growing peptide, attached to an integrated carrier domain, is delivered to neighboring catalytic domains for bond formation and modification. Investigation of these systems can lead to the discovery of new structures, unusual biosynthetic transformations, and to the engineering of catalysts for generating new products. The antimicrobial β-lactone obafluorin is produced nonribosomally from dihydroxybenzoic acid and a β-hydroxy amino acid that cyclizes into the β-lactone during product release. Here we report the structure of the nonribosomal peptide synthetase ObiF1, highlighting the structure of the β-lactone-producing thioesterase domain and an interaction between the C-terminal MbtH-like domain with an upstream adenylation domain. Biochemical assays examine catalytic promiscuity, provide mechanistic insight, and demonstrate utility for generating obafluorin analogs. These results advance our understanding of the structural cycle of nonribosomal peptide synthetases and provide insights into the production of β-lactone natural products. The antimicrobial β-lactone obafluorin is produced by a Nonribosomal Peptide Synthetase (NRPS). Here the authors present the crystal structure of the obafluorin NRPS and develop a reconstitution assay that allows them to analyse product formation from obafluorin NRPS mutants and alternate substrates.
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17
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Dhakal D, Rayamajhi V, Mishra R, Sohng JK. Bioactive molecules from Nocardia: diversity, bioactivities and biosynthesis. ACTA ACUST UNITED AC 2019; 46:385-407. [DOI: 10.1007/s10295-018-02120-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 12/19/2018] [Indexed: 02/06/2023]
Abstract
Abstract
Nocardia spp. are catalase positive, aerobic, and non-motile Gram-positive filamentous bacteria. Many Nocarida spp. have been reported as unusual causes of diverse clinical diseases in both humans and animals. Therefore, they have been studied for a long time, primarily focusing on strain characterization, taxonomic classification of new isolates, and host pathophysiology. Currently, there are emerging interests in isolating bioactive molecules from diverse actinobacteria including Nocardia spp. and studying their biosynthetic mechanisms. In addition, these species possess significant metabolic capacity, which has been utilized for generating diverse functionalized bioactive molecules by whole cell biotransformation. This review summarizes the structural diversity and biological activities of compounds biosynthesized or biotransformed by Nocardia spp. Furthermore, the recent advances on biosynthetic mechanisms and genetic engineering approaches for enhanced production or structural/functional modification are presented.
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Affiliation(s)
- Dipesh Dhakal
- 0000 0004 0533 4202 grid.412859.3 Department of Life Science and Biochemical Engineering SunMoon University 70 Sunmoon-ro 221, Tangjeong-myeon 31460 Asan-si Chungnam Republic of Korea
| | - Vijay Rayamajhi
- 0000 0004 0533 4202 grid.412859.3 Department of Life Science and Biochemical Engineering SunMoon University 70 Sunmoon-ro 221, Tangjeong-myeon 31460 Asan-si Chungnam Republic of Korea
| | - Ravindra Mishra
- 0000 0004 0533 4202 grid.412859.3 Department of Life Science and Biochemical Engineering SunMoon University 70 Sunmoon-ro 221, Tangjeong-myeon 31460 Asan-si Chungnam Republic of Korea
| | - Jae Kyung Sohng
- 0000 0004 0533 4202 grid.412859.3 Department of Life Science and Biochemical Engineering SunMoon University 70 Sunmoon-ro 221, Tangjeong-myeon 31460 Asan-si Chungnam Republic of Korea
- 0000 0004 0533 4202 grid.412859.3 Department of BT-Convergent Pharmaceutical Engineering SunMoon University 70 Sunmoon-ro 221, Tangjeong-myeon 31460 Asan-si Chungnam Republic of Korea
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18
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Kaysser L. Built to bind: biosynthetic strategies for the formation of small-molecule protease inhibitors. Nat Prod Rep 2019; 36:1654-1686. [DOI: 10.1039/c8np00095f] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The discovery and characterization of natural product protease inhibitors has inspired the development of numerous pharmaceutical agents.
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Affiliation(s)
- Leonard Kaysser
- Department of Pharmaceutical Biology
- University of Tübingen
- 72076 Tübingen
- Germany
- German Centre for Infection Research (DZIF)
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19
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Law BJC, Zhuo Y, Winn M, Francis D, Zhang Y, Samborskyy M, Murphy A, Ren L, Leadlay PF, Micklefield J. A vitamin K-dependent carboxylase orthologue is involved in antibiotic biosynthesis. Nat Catal 2018. [DOI: 10.1038/s41929-018-0178-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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20
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Auerbach D, Yan F, Zhang Y, Müller R. Characterization of an Unusual Glycerate Esterification Process in Vioprolide Biosynthesis. ACS Chem Biol 2018; 13:3123-3130. [PMID: 30286293 DOI: 10.1021/acschembio.8b00826] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Bacteria produce a large number of secondary metabolites with extraordinary chemical structures and bioactivities. Vioprolides are promising anticancer and antifungal lead compounds produced by the myxobacterium Cystobacter violaceus Cb vi35, which are initially synthesized as acylated precursors (previoprolides) by nonribosomal peptide synthetases (NRPS). Here, we describe and characterize an unprecedented glycerate esterification process in the biosynthesis of vioprolides. In vitro biochemical investigations revealed that the fatty acyl chain of previoprolides is adenylated by the starting fatty acyl-AMP ligase (FAAL) domain, while the glycerate moiety is incorporated by the FkbH domain. An unusual ester-bond forming condensation domain is shown responsible for the acylation of glycerate. LC-MS analysis and bioactivity assays suggest that the acylation serves for directed membrane transport rather than representing a prodrug mechanism.
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Affiliation(s)
- David Auerbach
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research and Department of Pharmacy, Saarland University, Saarland University Campus, Building E8.1, 66123 Saarbrücken, Germany
| | - Fu Yan
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research and Department of Pharmacy, Saarland University, Saarland University Campus, Building E8.1, 66123 Saarbrücken, Germany
| | - Youming Zhang
- Shandong University-Helmholtz Joint Institute of Biotechnology, State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Qingdao, People’s Republic of China
| | - Rolf Müller
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research and Department of Pharmacy, Saarland University, Saarland University Campus, Building E8.1, 66123 Saarbrücken, Germany
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21
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Mori S, Green KD, Choi R, Buchko GW, Fried MG, Garneau-Tsodikova S. Using MbtH-Like Proteins to Alter the Substrate Profile of a Nonribosomal Peptide Adenylation Enzyme. Chembiochem 2018; 19:2186-2194. [PMID: 30134012 DOI: 10.1002/cbic.201800240] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Revised: 08/21/2018] [Indexed: 01/19/2023]
Abstract
MbtH-like proteins (MLPs) are required for soluble expression and/or optimal activity of some adenylation (A) domains of nonribosomal peptide synthetases. Because A domains can interact with noncognate MLP partners, how the function of an A domain, TioK, involved in the biosynthesis of the bisintercalator thiocoraline, is altered by noncognate MLPs has been investigated. Measuring TioK activity with 12 different MLPs from a variety of bacterial species by using a radiometric assay suggested that the A domain substrate promiscuity could be altered by foreign MLPs. Kinetic studies and bioinformatics analysis expanded the complexity of MLP functions and interactions.
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Affiliation(s)
- Shogo Mori
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lee T. Todd, Jr. Building, 789 South Limestone St., Lexington, KY, 40536-0596, USA
| | - Keith D Green
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lee T. Todd, Jr. Building, 789 South Limestone St., Lexington, KY, 40536-0596, USA
| | - Ryan Choi
- University of Washington, Center for Emerging and Re-emerging Infectious Diseases, 750 Republican St., Seattle, WA, 98109, USA.,University of Washington, Seattle Structural Genomics Center for Infectious Diseases, 307 Westlake Avenue N, Seattle, WA, 98109, USA
| | - Garry W Buchko
- University of Washington, Seattle Structural Genomics Center for Infectious Diseases, 307 Westlake Avenue N, Seattle, WA, 98109, USA.,Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, P. O. Box 999, Richmond, WA, 99352, USA.,School of Molecular Biosciences, Washington State University, P. O. Box 647520, Pullman, WA, 99164, USA
| | - Michael G Fried
- Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky, Biological Sciences Research Bldg, 741 South Limestone St., Lexington, KY, 40536-0509, USA
| | - Sylvie Garneau-Tsodikova
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lee T. Todd, Jr. Building, 789 South Limestone St., Lexington, KY, 40536-0596, USA
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22
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Rabe P, Kamps JJAG, Schofield CJ, Lohans CT. Roles of 2-oxoglutarate oxygenases and isopenicillin N synthase in β-lactam biosynthesis. Nat Prod Rep 2018; 35:735-756. [PMID: 29808887 PMCID: PMC6097109 DOI: 10.1039/c8np00002f] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Indexed: 01/01/2023]
Abstract
Covering: up to 2017 2-Oxoglutarate (2OG) dependent oxygenases and the homologous oxidase isopenicillin N synthase (IPNS) play crucial roles in the biosynthesis of β-lactam ring containing natural products. IPNS catalyses formation of the bicyclic penicillin nucleus from a tripeptide. 2OG oxygenases catalyse reactions that diversify the chemistry of β-lactams formed by both IPNS and non-oxidative enzymes. Reactions catalysed by the 2OG oxygenases of β-lactam biosynthesis not only involve their typical hydroxylation reactions, but also desaturation, epimerisation, rearrangement, and ring-forming reactions. Some of the enzymes involved in β-lactam biosynthesis exhibit remarkable substrate and product selectivities. We review the roles of 2OG oxygenases and IPNS in β-lactam biosynthesis, highlighting opportunities for application of knowledge of their roles, structures, and mechanisms.
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Affiliation(s)
- Patrick Rabe
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| | - Jos J A G Kamps
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| | - Christopher J Schofield
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| | - Christopher T Lohans
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
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23
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Mori S, Garzan A, Tsodikov OV, Garneau-Tsodikova S. Deciphering Nature’s Intricate Way of N,S-Dimethylating l-Cysteine: Sequential Action of Two Bifunctional Adenylation Domains. Biochemistry 2017; 56:6087-6097. [DOI: 10.1021/acs.biochem.7b00980] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shogo Mori
- Department of Pharmaceutical
Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536-0596, United States
| | - Atefeh Garzan
- Department of Pharmaceutical
Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536-0596, United States
| | - Oleg V. Tsodikov
- Department of Pharmaceutical
Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536-0596, United States
| | - Sylvie Garneau-Tsodikova
- Department of Pharmaceutical
Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536-0596, United States
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24
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Payne JAE, Schoppet M, Hansen MH, Cryle MJ. Diversity of nature's assembly lines - recent discoveries in non-ribosomal peptide synthesis. MOLECULAR BIOSYSTEMS 2017; 13:9-22. [PMID: 27853778 DOI: 10.1039/c6mb00675b] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The biosynthesis of complex natural products by non-ribosomal peptide synthetases (NRPSs) and the related polyketide synthases (PKSs) represents a major source of important bioactive compounds. These large, multi-domain machineries are able to produce a fascinating range of molecules due to the nature of their modular architectures, which allows natural products to be assembled and tailored in a modular, step-wise fashion. In recent years there has been significant progress in characterising the important domains and underlying mechanisms of non-ribosomal peptide synthesis. More significantly, several studies have uncovered important examples of novel activity in many NRPS domains. These discoveries not only greatly increase the structural diversity of the possible products of NRPS machineries but - possibly more importantly - they improve our understanding of what is a highly important, yet complex, biosynthetic apparatus. In this review, several recent examples of novel NRPS function will be introduced, which highlight the range of previously uncharacterised activities that have now been detected in the biosynthesis of important natural products by these mega-enzyme synthetases.
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Affiliation(s)
- Jennifer A E Payne
- EMBL Australia, Monash University, Clayton, Victoria 3800, Australia and The Monash Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology and ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia.
| | - Melanie Schoppet
- EMBL Australia, Monash University, Clayton, Victoria 3800, Australia and The Monash Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology and ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia.
| | | | - Max J Cryle
- EMBL Australia, Monash University, Clayton, Victoria 3800, Australia and The Monash Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology and ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia.
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25
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Waldman AJ, Ng TL, Wang P, Balskus EP. Heteroatom-Heteroatom Bond Formation in Natural Product Biosynthesis. Chem Rev 2017; 117:5784-5863. [PMID: 28375000 PMCID: PMC5534343 DOI: 10.1021/acs.chemrev.6b00621] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Natural products that contain functional groups with heteroatom-heteroatom linkages (X-X, where X = N, O, S, and P) are a small yet intriguing group of metabolites. The reactivity and diversity of these structural motifs has captured the interest of synthetic and biological chemists alike. Functional groups containing X-X bonds are found in all major classes of natural products and often impart significant biological activity. This review presents our current understanding of the biosynthetic logic and enzymatic chemistry involved in the construction of X-X bond containing functional groups within natural products. Elucidating and characterizing biosynthetic pathways that generate X-X bonds could both provide tools for biocatalysis and synthetic biology, as well as guide efforts to uncover new natural products containing these structural features.
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Affiliation(s)
- Abraham J. Waldman
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, United States
| | - Tai L. Ng
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, United States
| | - Peng Wang
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, United States
| | - Emily P. Balskus
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, United States
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26
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Li R, Oliver RA, Townsend CA. Identification and Characterization of the Sulfazecin Monobactam Biosynthetic Gene Cluster. Cell Chem Biol 2017; 24:24-34. [PMID: 28017601 PMCID: PMC5286544 DOI: 10.1016/j.chembiol.2016.11.010] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 10/18/2016] [Accepted: 11/17/2016] [Indexed: 11/16/2022]
Abstract
The monobactams, exemplified by the natural product sulfazecin, are the only class of β-lactam antibiotics not inactivated by metallo-β-lactamases, which confer bacteria with extended-spectrum β-lactam resistance. We screened a transposon mutagenesis library from Pseudomonas acidophila ATCC 31363 and isolated a sulfazecin-deficient mutant that revealed a gene cluster encoding two non-ribosomal peptide synthetases (NRPSs), a methyltransferase, a sulfotransferase, and a dioxygenase. Three modules and an aberrant C-terminal thioesterase (TE) domain are distributed across the two NRPSs. Biochemical examination of the adenylation (A) domains provided evidence that L-2,3-diaminopropionate, not L-serine as previously thought, is the direct source of the β-lactam ring of sulfazecin. ATP/PPi exchange assay also revealed an unusual substrate selectivity shift of one A domain when expressed with or without the immediately upstream condensation domain. Gene inactivation analysis defined a cluster of 13 open reading frames sufficient for sulfazecin production, precursor synthesis, self-resistance, and regulation. The identification of a key intermediate supported a proposed NRPS-mediated mechanism of sulfazecin biosynthesis and β-lactam ring formation distinct from the nocardicins, another NRPS-derived subclass of monocyclic β-lactam. These findings will serve as the basis for further biosynthetic research and potential engineering of these important antibiotics.
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Affiliation(s)
- Rongfeng Li
- Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA
| | - Ryan A Oliver
- Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA
| | - Craig A Townsend
- Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA.
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27
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Trautman EP, Crawford JM. Linking Biosynthetic Gene Clusters to their Metabolites via Pathway- Targeted Molecular Networking. Curr Top Med Chem 2016; 16:1705-16. [PMID: 26456470 PMCID: PMC5055756 DOI: 10.2174/1568026616666151012111046] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 08/25/2015] [Accepted: 09/08/2015] [Indexed: 12/16/2022]
Abstract
The connection of microbial biosynthetic gene clusters to the small molecule metabolites they encode is central to the discovery and characterization of new metabolic pathways with ecological and pharmacological potential. With increasing microbial genome sequence information being deposited into publicly available databases, it is clear that microbes have the coding capacity for many more biologically active small molecules than previously realized. Of increasing interest are the small molecules encoded by the human microbiome, as these metabolites likely mediate a variety of currently uncharacterized human-microbe interactions that influence health and disease. In this mini-review, we describe the ongoing biosynthetic, structural, and functional characterizations of the genotoxic colibactin pathway in gut bacteria as a thematic example of linking biosynthetic gene clusters to their metabolites. We also highlight other natural products that are produced through analogous biosynthetic logic and comment on some current disconnects between bioinformatics predictions and experimental structural characterizations. Lastly, we describe the use of pathway-targeted molecular networking as a tool to characterize secondary metabolic pathways within complex metabolomes and to aid in downstream metabolite structural elucidation efforts.
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Affiliation(s)
| | - Jason M Crawford
- Department of Chemistry, Faculty of Yale University, P.O. Box: 27392, West Haven, CT, 06516, USA.
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28
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Brieke C, Kratzig V, Peschke M, Cryle MJ. Facile Synthetic Access to Glycopeptide Antibiotic Precursor Peptides for the Investigation of Cytochrome P450 Action in Glycopeptide Antibiotic Biosynthesis. Methods Mol Biol 2016; 1401:85-102. [PMID: 26831703 DOI: 10.1007/978-1-4939-3375-4_6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The glycopeptide antibiotics are an important class of complex, medically relevant peptide natural products. Given that the production of such compounds all stems from in vivo biosynthesis, understanding the mechanisms of the natural assembly system--consisting of a nonribosomal-peptide synthetase machinery (NRPS) and further modifying enzymes--is vital. In order to address the later steps of peptide biosynthesis, which are catalyzed by Cytochrome P450s that interact with the peptide-producing nonribosomal peptide synthetase, peptide substrates are required: these peptides must also be in a form that can be conjugated to carrier protein domains of the nonribosomal peptide synthetase machinery. Here, we describe a practical and effective route for the solid phase synthesis of glycopeptide antibiotic precursor peptides as their Coenzyme A (CoA) conjugates to allow enzymatic conjugation to carrier protein domains. This route utilizes Fmoc-chemistry suppressing epimerization of racemization-prone aryl glycine derivatives and affords high yields and excellent purities, requiring only a single step of simple solid phase extraction for chromatographic purification. With this, comprehensive investigations of interactions between various NRPS-bound substrates and Cytochrome P450s are enabled.
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Affiliation(s)
- Clara Brieke
- Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Jahnstrasse 29, Heidelberg, 69120, Germany
| | - Veronika Kratzig
- Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Jahnstrasse 29, Heidelberg, 69120, Germany
| | - Madeleine Peschke
- Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Jahnstrasse 29, Heidelberg, 69120, Germany
| | - Max J Cryle
- Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Jahnstrasse 29, Heidelberg, 69120, Germany.
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29
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Townsend CA. Convergent biosynthetic pathways to β-lactam antibiotics. Curr Opin Chem Biol 2016; 35:97-108. [PMID: 27693891 DOI: 10.1016/j.cbpa.2016.09.013] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 09/14/2016] [Accepted: 09/15/2016] [Indexed: 02/05/2023]
Abstract
Five naturally-occurring families of β-lactams have inspired a class of drugs that constitute >60% of the antimicrobials used in human medicine. Their biosynthetic pathways reveal highly individualized synthetic strategies that yet converge on a common azetidinone ring assembled in structural contexts that confer selective binding and inhibition of d,d-transpeptidases that play essential roles in bacterial cell wall (peptidoglycan) biosynthesis. These enzymes belong to a single 'clan' of evolutionarily distinct serine hydrolases whose active site geometry and mechanism of action is specifically matched by these antibiotics for inactivation that is kinetically competitive with their native function. Unusual enzyme-mediated reactions and catalytic multitasking in these pathways are discussed with particular attention to the diverse ways the β-lactam itself is generated, and more broadly how the intrinsic reactivity of this core structural element is modulated in natural systems through the introduction of ring strain and electronic effects.
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Affiliation(s)
- Craig A Townsend
- Department of Chemistry, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA.
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30
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Saha S, Rokita SE. An Activator of an Adenylation Domain Revealed by Activity but Not Sequence Homology. Chembiochem 2016; 17:1818-1823. [PMID: 27447757 DOI: 10.1002/cbic.201600291] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Indexed: 11/10/2022]
Abstract
Nonribosomal peptide synthetases (NRPSs), which are responsible for synthesizing many medicinally important natural products, frequently use adenylation domain activators (ADAs) to promote substrate loading. Although ADAs are usually MbtH-like proteins (MLPs), a new type of ADA appears to promote an NRPS-dependent incorporation of a dihydropyrrole unit into sibiromycin. The adenylation and thiolation didomain of the NRPS SibD catalyzes the adenylation of a limited number of amino acids including l-Tyr, the precursor in dihydropyrrole biosynthesis, as determined by a standard radioactivity exchange assay. LC-MS/MS analysis confirmed loading of l-Tyr onto the thiolation domain. SibB, a small protein with no prior functional assignment or sequence homology to MLPs, was found to promote the exchange activity. MLPs from bacteria expressing homologous biosynthetic pathways were unable to replace this function of SibB. The discovery of this new type of ADA demonstrates the importance of searching beyond the conventional MLP standard for proteins affecting NRPS activity.
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Affiliation(s)
- Shalini Saha
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, 20742, USA.
| | - Steven E Rokita
- Department of Chemistry, Johns Hopkins University, 3400 N. Charles St, Baltimore, MD, 21218, USA.
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31
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Vij V, Bhalla V, Kumar M. Hexaarylbenzene: Evolution of Properties and Applications of Multitalented Scaffold. Chem Rev 2016; 116:9565-627. [DOI: 10.1021/acs.chemrev.6b00144] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Varun Vij
- Department of Chemistry,
UGC Centre for Advanced Studies, Guru Nanak Dev University, Amritsar, Punjab 143005, India
| | - Vandana Bhalla
- Department of Chemistry,
UGC Centre for Advanced Studies, Guru Nanak Dev University, Amritsar, Punjab 143005, India
| | - Manoj Kumar
- Department of Chemistry,
UGC Centre for Advanced Studies, Guru Nanak Dev University, Amritsar, Punjab 143005, India
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Lee K, Lee B, Ryu J, Kim D, Kim Y, Lim SK. Increased vancomycin production by overexpression of MbtH-like protein in Amycolatopsis orientalis
KFCC10990P. Lett Appl Microbiol 2016; 63:222-8. [DOI: 10.1111/lam.12617] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 07/13/2016] [Accepted: 07/14/2016] [Indexed: 01/18/2023]
Affiliation(s)
- K.S. Lee
- GenoTech Corporation; Daejeon Korea
- College of Pharmacy; Chungnam National University; Daejeon Korea
| | - B.M. Lee
- GenoTech Corporation; Daejeon Korea
| | - J.H. Ryu
- GenoTech Corporation; Daejeon Korea
| | - D.H. Kim
- GenoTech Corporation; Daejeon Korea
| | - Y.H. Kim
- College of Pharmacy; Chungnam National University; Daejeon Korea
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Pang B, Wang M, Liu W. Cyclization of polyketides and non-ribosomal peptides on and off their assembly lines. Nat Prod Rep 2016; 33:162-73. [PMID: 26604034 DOI: 10.1039/c5np00095e] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Modular polyketide synthases (PKSs) and non-ribosomal peptide synthetases (NRPSs) are multifunctional megaenzymes that serve as templates to program the assembly of short carboxylic acids and amino acids in a primarily co-linear manner. The variation, combination, permutation and evolution of their functional units (e.g., modules, domains and proteins) along with their association with external enzymes have resulted in the generation of numerous versions of templates, the roles of which have not been fully recognized in the structural diversification of polyketides, non-ribosomal peptides and their hybrids present in nature. In this Highlight, we focus on the assembly-line enzymology and associated chemistry by providing examples of some newly characterized cyclization reactions that occur on and off the assembly lines during and after chain elongation for the purpose of elucidating the template effects of PKSs and NRPSs. A fundamental understanding of the underlying biosynthetic logic would facilitate the elucidation of chemical information contained within the PKS or NRPS templates and benefit the development of strategies for genome mining, biosynthesis-inspired chemical synthesis and combinatorial biosynthesis.
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Affiliation(s)
- Bo Pang
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China.
| | - Min Wang
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China.
| | - Wen Liu
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China. and Huzhou Center of Bio-Synthetic Innovation, 1366 Hongfeng Road, Huzhou 313000, China
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Shrestha SK, Garneau-Tsodikova S. Expanding Substrate Promiscuity by Engineering a Novel Adenylating-Methylating NRPS Bifunctional Enzyme. Chembiochem 2016; 17:1328-32. [PMID: 27128382 DOI: 10.1002/cbic.201600234] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Indexed: 12/11/2022]
Abstract
Nonribosomal peptides synthetases (NRPSs), which are multifunctional mega-enzymes producing many biologically active metabolites, are ideal targets for enzyme engineering. NRPS adenylation domains play a critical role in selecting/activating the amino acids to be transferred to downstream NRPS domains in the biosynthesis of natural products. Both monofunctional and bifunctional A domains interrupted with an auxiliary domain are found in nature. Here, we show that a bifunctional interrupted A domain can be uninterrupted by deleting its methyltransferase auxiliary domain portion to make an active monofunctional enzyme. We also demonstrate that a portion of an auxiliary domain with almost no sequence identity to the original auxiliary domain can be insert into naturally interrupted A domain to develop a new active bifunctional A domain with increased substrate profile. This work shows promise for the creation of new interrupted A domains in engineered NRPS enzymes.
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Affiliation(s)
- Sanjib K Shrestha
- Department of Pharmaceutical Sciences, University of Kentucky, BioPharm Complex (Room 423), 789 South Limestone Street, Lexington, KY, 40536-0596, USA
| | - Sylvie Garneau-Tsodikova
- Department of Pharmaceutical Sciences, University of Kentucky, BioPharm Complex (Room 423), 789 South Limestone Street, Lexington, KY, 40536-0596, USA.
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Kittilä T, Schoppet M, Cryle MJ. Online Pyrophosphate Assay for Analyzing Adenylation Domains of Nonribosomal Peptide Synthetases. Chembiochem 2016; 17:576-84. [PMID: 26751610 DOI: 10.1002/cbic.201500555] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Indexed: 12/12/2022]
Abstract
Nonribosomal peptide synthetases (NRPSs) produce many important and structurally complex natural products. Because of their architectures, reprogramming NRPSs has long been attempted to access new bioactive compounds. However, detailed characterization of NRPS catalysis and substrate selectivity by adenylation (A) domains is needed to support such efforts. We present a simple coupled NADH/pyrophosphate (PPi ) detection assay for analyzing A domain catalysis in vitro. PPi formation is coupled to the consumption of NADH by four enzymatic steps and is detected spectroscopically (λ=340 nm) for simple analysis. We demonstrate the effectiveness of this assay with several adenylation domains, including a stand-alone A domain (DltA, cell wall biosynthesis) and an embedded A domain (Tcp10, teicoplanin biosynthesis). Substrate acceptance of the Tcp10 A domain was explored for the first time, thus demonstrating the applicability of the assay for complex, multi-domain NRPSs.
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Affiliation(s)
- Tiia Kittilä
- Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Jahnstrasse 29, 69120 Heidelberg, Germany
| | - Melanie Schoppet
- Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Jahnstrasse 29, 69120 Heidelberg, Germany
| | - Max J Cryle
- Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Jahnstrasse 29, 69120 Heidelberg, Germany. .,EMBL Australia, Monash University, Clayton, Victoria, 3800, Australia. .,The Department of Biochemistry and Molecular Biology and, ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, 15 Innovation Walk, Clayton, Victoria, 3800, Australia.
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36
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Directed evolution of the tryptophan synthase β-subunit for stand-alone function recapitulates allosteric activation. Proc Natl Acad Sci U S A 2015; 112:14599-604. [PMID: 26553994 DOI: 10.1073/pnas.1516401112] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Enzymes in heteromeric, allosterically regulated complexes catalyze a rich array of chemical reactions. Separating the subunits of such complexes, however, often severely attenuates their catalytic activities, because they can no longer be activated by their protein partners. We used directed evolution to explore allosteric regulation as a source of latent catalytic potential using the β-subunit of tryptophan synthase from Pyrococcus furiosus (PfTrpB). As part of its native αββα complex, TrpB efficiently produces tryptophan and tryptophan analogs; activity drops considerably when it is used as a stand-alone catalyst without the α-subunit. Kinetic, spectroscopic, and X-ray crystallographic data show that this lost activity can be recovered by mutations that reproduce the effects of complexation with the α-subunit. The engineered PfTrpB is a powerful platform for production of Trp analogs and for further directed evolution to expand substrate and reaction scope.
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37
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Labby KJ, Watsula SG, Garneau-Tsodikova S. Interrupted adenylation domains: unique bifunctional enzymes involved in nonribosomal peptide biosynthesis. Nat Prod Rep 2015; 32:641-53. [PMID: 25622971 DOI: 10.1039/c4np00120f] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Nonribosomal peptides (NRPs) account for a large portion of drugs and drug leads currently available in the pharmaceutical industry. They are one of two main families of natural products biosynthesized on megaenzyme assembly-lines composed of multiple modules that are, in general, each comprised of three core domains and on occasion of accompanying auxiliary domains. The core adenylation (A) domains are known to delineate the identity of the specific chemical components to be incorporated into the growing NRPs. Previously believed to be inactive, A domains interrupted by auxiliary enzymes have recently been proven to be active and capable of performing two distinct chemical reactions. This highlight summarizes current knowledge on A domains and presents the various interrupted A domains found in a number of nonribosomal peptide synthetase (NRPS) assembly-lines, their predicted or proven dual functions, and their potential for manipulation and engineering for chemoenzymatic synthesis of new pharmaceutical agents with increased potency.
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Affiliation(s)
- Kristin J Labby
- Beloit College, Department of Chemistry, 700 College Street, Beloit, WI 53511, USA
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Fu C, Keller L, Bauer A, Brönstrup M, Froidbise A, Hammann P, Herrmann J, Mondesert G, Kurz M, Schiell M, Schummer D, Toti L, Wink J, Müller R. Biosynthetic Studies of Telomycin Reveal New Lipopeptides with Enhanced Activity. J Am Chem Soc 2015; 137:7692-705. [DOI: 10.1021/jacs.5b01794] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Chengzhang Fu
- Helmholtz Institute for Pharmaceutical Research Saarland, Helmholtz
Centre for Infection Research, and Department of Pharmaceutical Biotechnology, Saarland University, Building C 2.3, 66123, Saarbrücken, Germany
| | - Lena Keller
- Helmholtz Institute for Pharmaceutical Research Saarland, Helmholtz
Centre for Infection Research, and Department of Pharmaceutical Biotechnology, Saarland University, Building C 2.3, 66123, Saarbrücken, Germany
- German Centre for Infection Research, Inhoffenstraße 7, 38124 Braunschweig, Germany
| | - Armin Bauer
- R&D LGCR, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926 Frankfurt am Main, Germany
| | - Mark Brönstrup
- German Centre for Infection Research, Inhoffenstraße 7, 38124 Braunschweig, Germany
- R&D LGCR, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926 Frankfurt am Main, Germany
| | - Alexandre Froidbise
- TSU Infectious Diseases, Sanofi R&D, 195 Route d‘Espagne, 31036 Toulouse, France
| | - Peter Hammann
- R&D TSU Infectious Diseases, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926 Frankfurt am Main, Germany
| | - Jennifer Herrmann
- Helmholtz Institute for Pharmaceutical Research Saarland, Helmholtz
Centre for Infection Research, and Department of Pharmaceutical Biotechnology, Saarland University, Building C 2.3, 66123, Saarbrücken, Germany
- German Centre for Infection Research, Inhoffenstraße 7, 38124 Braunschweig, Germany
| | - Guillaume Mondesert
- TSU Infectious Diseases, Sanofi R&D, 195 Route d‘Espagne, 31036 Toulouse, France
| | - Michael Kurz
- R&D LGCR, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926 Frankfurt am Main, Germany
| | - Matthias Schiell
- R&D LGCR, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926 Frankfurt am Main, Germany
| | - Dietmar Schummer
- R&D LGCR, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926 Frankfurt am Main, Germany
| | - Luigi Toti
- R&D LGCR, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926 Frankfurt am Main, Germany
| | - Joachim Wink
- R&D LGCR, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926 Frankfurt am Main, Germany
| | - Rolf Müller
- Helmholtz Institute for Pharmaceutical Research Saarland, Helmholtz
Centre for Infection Research, and Department of Pharmaceutical Biotechnology, Saarland University, Building C 2.3, 66123, Saarbrücken, Germany
- German Centre for Infection Research, Inhoffenstraße 7, 38124 Braunschweig, Germany
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Al-Mestarihi AH, Garzan A, Kim JM, Garneau-Tsodikova S. Enzymatic Evidence for a Revised Congocidine Biosynthetic Pathway. Chembiochem 2015; 16:1307-13. [DOI: 10.1002/cbic.201402711] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Indexed: 12/25/2022]
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Gaudelli NM, Long DH, Townsend CA. β-Lactam formation by a non-ribosomal peptide synthetase during antibiotic biosynthesis. Nature 2015; 520:383-7. [PMID: 25624104 PMCID: PMC4401618 DOI: 10.1038/nature14100] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2014] [Accepted: 11/19/2014] [Indexed: 01/23/2023]
Abstract
Non-ribosomal peptide synthetases (NRPSs) are giant enzymes comprised of modules that house repeated sets of functional domains, which select, activate and couple amino acids drawn from a pool of nearly 500 potential building blocks.1 The structurally and stereochemically diverse peptides generated in this manner underlie the biosynthesis of a large sector of natural products. Many of their derived metabolites are bioactive such as the antibiotics vancomycin, bacitracin, daptomycin and the β-lactam-containing penicillins, cephalosporins and nocardicins. Although penicillins and cephalosporins are synthesised from a classically derived NRPS tripeptide (from ACVS, δ-(L-α-aminoadipyl)–L-cysteinyl–D-valine synthetase)2, we now report an unprecedented NRPS activity to both assemble a serine-containing peptide and mediate its cyclisation to the critical β-lactam ring of the nocardicin family of antibiotics. A histidine-rich condensation (C) domain, which typically carries out peptide bond formation during product assembly, was found to also synthesise the embedded 4-membered ring. Here, a mechanism is proposed and supporting experiments are described, which is distinct from the pathways that have evolved to the three other β-lactam antibiotic families: penicillin/cephalosporins, clavams and carbapenems. These findings raise the possibility that β-lactam rings can be regio- and stereospecifically integrated into engineered peptides for application as, for example, targeted protease inactivators.3,4
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Affiliation(s)
- Nicole M Gaudelli
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Darcie H Long
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Craig A Townsend
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, USA
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41
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Al-Mestarihi AH, Villamizar G, Fernández J, Zolova OE, Lombó F, Garneau-Tsodikova S. Adenylation and S-methylation of cysteine by the bifunctional enzyme TioN in thiocoraline biosynthesis. J Am Chem Soc 2014; 136:17350-4. [PMID: 25409494 DOI: 10.1021/ja510489j] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The antitumor agent thiocoraline is a nonribosomally biosynthesized bisintercalator natural product, which contains in its peptidic backbone two S-methylated l-cysteine residues. S-Methylation occurs very rarely in nature, and is observed extremely rarely in nonribosomal peptide scaffolds. We have proposed that during thiocoraline biosynthesis, TioN, a stand-alone adenylation domain interrupted by the S-adenosyl-l-methionine binding region of a methyltransferase enzyme, is capable of performing two functions: the adenylation and S-methylation of l-cysteine. Herein, by preparation of knockouts of TioN and its MbtH-like protein partner TioT, we confirmed their role in thiocoraline biosynthesis. We also co-expressed recombinant TioN and TioT and biochemically investigated three potential pathways involving activation, methylation, and loading of l-cysteine onto the TioN partner thiolation domain, TioS(T4). The valuable insights gained into the pathway(s) followed for the production of S-Me-l-Cys-S-TioS(T4) will serve as a guide for the development of novel engineered interrupted adenylation enzymes for combinatorial biosynthesis.
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Affiliation(s)
- Ahmad H Al-Mestarihi
- Department of Pharmaceutical Sciences, University of Kentucky , Lexington, Kentucky 40536-0596, United States
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Abstract
In this viewpoint highlights are drawn from a deep analysis of the multifaceted problem of aflatoxin biosynthesis, one of the most highly rearranged polyketide natural products known. Fundamental chemical insights have emerged into how cytochrome P450-mediated skeletal rearrangements occur through probable cationic intermediates and oxidative dearomatizations, which are applicable more widely in natural product catabolism. So to where current experimental methods have failed in our hands, bioinformatic tools and fresh experimental strategies have been developed to identify linker regions in large, polydomain proteins and guide the dissection and reassembly of their component parts. It has been possible to deduce individual catalytic roles, how overall synthesis is coordinated and how these enzymes can be re-engineered in a rational manner to prepare non-natural products. These insights and innovations were often not planned or anticipated, but sprung from the inability to answer fundamental questions. Advances in science can take place by chance favoring the prepared mind, other times by refusing to give up and devising new solutions to address hard questions. Both ways forward played important roles in the investigation of aflatoxin biosynthesis. For these contributions I am pleased to share this special issue of NPR with John Vederas and Tom Simpson, who have been leaders in this field for the last third of a century.
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Affiliation(s)
- Craig A Townsend
- Department of Chemistry, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA.
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Gaudelli NM, Townsend CA. Epimerization and substrate gating by a TE domain in β-lactam antibiotic biosynthesis. Nat Chem Biol 2014; 10:251-8. [PMID: 24531841 PMCID: PMC3961552 DOI: 10.1038/nchembio.1456] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2013] [Accepted: 12/30/2013] [Indexed: 12/01/2022]
Abstract
Nonribosomal peptide synthetases are versatile engines of bioactive natural product biosynthesis that function according to the multiple carrier thiotemplate mechanism. C-terminal thioesterase (TE) domains of these giant modular proteins typically catalyze product release by hydrolysis or macrocyclization. We now report an unprecedented, dual-function TE that is involved in the biosynthesis of nocardicin A, which is the paradigm monocyclic β-lactam antibiotic. Contrary to our expectation, a stereodefined series of potential peptide substrates for the nocardicin TE domain failed to undergo hydrolysis. The stringent discrimination against peptide intermediates was overcome by prior monocyclic β-lactam formation at an L-seryl site. Kinetic data are interpreted such that the TE domain acts as a gatekeeper to hold the assembling peptide on an upstream domain until β-lactam formation takes place and then rapidly catalyzes epimerization, which has not been observed previously as a TE catalytic function, and thioesterase cleavage to discharge a fully fledged pentapeptide β-lactam harboring nocardicin G, the universal precursor of the nocardicins.
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Affiliation(s)
- Nicole M. Gaudelli
- Department of Chemistry, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218
| | - Craig A. Townsend
- Department of Chemistry, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218
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Wilson MC, Mori T, Rückert C, Uria AR, Helf MJ, Takada K, Gernert C, Steffens UAE, Heycke N, Schmitt S, Rinke C, Helfrich EJN, Brachmann AO, Gurgui C, Wakimoto T, Kracht M, Crüsemann M, Hentschel U, Abe I, Matsunaga S, Kalinowski J, Takeyama H, Piel J. An environmental bacterial taxon with a large and distinct metabolic repertoire. Nature 2014. [PMID: 24476823 DOI: 10.1038/nature12959.erratum.in:nature507:262] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Abstract
Cultivated bacteria such as actinomycetes are a highly useful source of biomedically important natural products. However, such 'talented' producers represent only a minute fraction of the entire, mostly uncultivated, prokaryotic diversity. The uncultured majority is generally perceived as a large, untapped resource of new drug candidates, but so far it is unknown whether taxa containing talented bacteria indeed exist. Here we report the single-cell- and metagenomics-based discovery of such producers. Two phylotypes of the candidate genus 'Entotheonella' with genomes of greater than 9 megabases and multiple, distinct biosynthetic gene clusters co-inhabit the chemically and microbially rich marine sponge Theonella swinhoei. Almost all bioactive polyketides and peptides known from this animal were attributed to a single phylotype. 'Entotheonella' spp. are widely distributed in sponges and belong to an environmental taxon proposed here as candidate phylum 'Tectomicrobia'. The pronounced bioactivities and chemical uniqueness of 'Entotheonella' compounds provide significant opportunities for ecological studies and drug discovery.
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Affiliation(s)
- Micheal C Wilson
- 1] Institute of Microbiology, Eidgenössische Technische Hochschule Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland [2] Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany [3]
| | - Tetsushi Mori
- 1] Faculty of Science and Engineering, Waseda University Center for Advanced Biomedical Sciences, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan [2]
| | - Christian Rückert
- Institute for Genome Research and Systems Biology, Center for Biotechnology, Universität Bielefeld, Universitätstrasse 25, 33594 Bielefeld, Germany
| | - Agustinus R Uria
- 1] Institute of Microbiology, Eidgenössische Technische Hochschule Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland [2] Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany
| | - Maximilian J Helf
- 1] Institute of Microbiology, Eidgenössische Technische Hochschule Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland [2] Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany
| | - Kentaro Takada
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Christine Gernert
- Department of Botany II, Julius-von-Sachs Institute for Biological Sciences, University of Würzburg, Julius-von-Sachs-Platz 3, 97082 Würzburg, Germany
| | - Ursula A E Steffens
- Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany
| | - Nina Heycke
- Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany
| | - Susanne Schmitt
- Department of Earth and Environmental Sciences, Palaeontology and Geobiology, Ludwig Maximilians University Munich, Richard-Wagner-Strasse 10, 80333 Munich, Germany
| | - Christian Rinke
- Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, California 94598, USA
| | - Eric J N Helfrich
- 1] Institute of Microbiology, Eidgenössische Technische Hochschule Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland [2] Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany
| | - Alexander O Brachmann
- Institute of Microbiology, Eidgenössische Technische Hochschule Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland
| | - Cristian Gurgui
- Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany
| | - Toshiyuki Wakimoto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Matthias Kracht
- Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany
| | - Max Crüsemann
- Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany
| | - Ute Hentschel
- Department of Botany II, Julius-von-Sachs Institute for Biological Sciences, University of Würzburg, Julius-von-Sachs-Platz 3, 97082 Würzburg, Germany
| | - Ikuro Abe
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Shigeki Matsunaga
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Jörn Kalinowski
- Institute for Genome Research and Systems Biology, Center for Biotechnology, Universität Bielefeld, Universitätstrasse 25, 33594 Bielefeld, Germany
| | - Haruko Takeyama
- Faculty of Science and Engineering, Waseda University Center for Advanced Biomedical Sciences, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Jörn Piel
- 1] Institute of Microbiology, Eidgenössische Technische Hochschule Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland [2] Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany
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Baltz RH. MbtH homology codes to identify gifted microbes for genome mining. ACTA ACUST UNITED AC 2014; 41:357-69. [DOI: 10.1007/s10295-013-1360-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2013] [Accepted: 09/30/2013] [Indexed: 11/24/2022]
Abstract
Abstract
Advances in DNA sequencing technologies have made it possible to sequence large numbers of microbial genomes rapidly and inexpensively. In recent years, genome sequencing initiatives have demonstrated that actinomycetes with large genomes generally have the genetic potential to produce many secondary metabolites, most of which remain cryptic. Since the numbers of new and novel pathways vary considerably among actinomycetes, and the correct assembly of secondary metabolite pathways containing type I polyketide synthase or nonribosomal peptide synthetase (NRPS) genes is costly and time consuming, it would be advantageous to have simple genetic predictors for the number and potential novelty of secondary metabolite pathways in targeted microorganisms. For secondary metabolite pathways that utilize NRPS mechanisms, the small chaperone-like proteins related to MbtH encoded by Mycobacterium tuberculosis offer unique probes or beacons to identify gifted microbes encoding large numbers of diverse NRPS pathways because of their unique function(s) and small size. The small size of the mbtH-homolog genes makes surveying large numbers of genomes straight-forward with less than ten-fold sequencing coverage. Multiple MbtH orthologs and paralogs have been coupled to generate a 24-mer multiprobe to assign numerical codes to individual MbtH homologs by BLASTp analysis. This multiprobe can be used to identify gifted microbes encoding new and novel secondary metabolites for further focused exploration by extensive DNA sequencing, pathway assembly and annotation, and expression studies in homologous or heterologous hosts.
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Affiliation(s)
- Richard H Baltz
- CognoGen Biotechnology Consulting 7636 Andora Drive 34238 Sarasota FL USA
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46
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An environmental bacterial taxon with a large and distinct metabolic repertoire. Nature 2014; 506:58-62. [DOI: 10.1038/nature12959] [Citation(s) in RCA: 454] [Impact Index Per Article: 45.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Accepted: 12/18/2013] [Indexed: 12/11/2022]
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KtzJ-dependent serine activation and O-methylation by KtzH for kutznerides biosynthesis. J Antibiot (Tokyo) 2013; 67:59-64. [DOI: 10.1038/ja.2013.98] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Revised: 08/28/2013] [Accepted: 09/03/2013] [Indexed: 12/11/2022]
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Pu JY, Peng C, Tang MC, Zhang Y, Guo JP, Song LQ, Hua Q, Tang GL. Naphthyridinomycin Biosynthesis Revealing the Use of Leader Peptide to Guide Nonribosomal Peptide Assembly. Org Lett 2013; 15:3674-7. [DOI: 10.1021/ol401549y] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Jin-Yue Pu
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China, and State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Chao Peng
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China, and State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Man-Cheng Tang
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China, and State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Yue Zhang
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China, and State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Jian-Ping Guo
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China, and State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Li-Qiang Song
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China, and State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Qiang Hua
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China, and State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Gong-Li Tang
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China, and State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
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Gaudelli NM, Townsend CA. Stereocontrolled syntheses of peptide thioesters containing modified seryl residues as probes of antibiotic biosynthesis. J Org Chem 2013; 78:6412-26. [PMID: 23758494 PMCID: PMC3898789 DOI: 10.1021/jo4007893] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Methods have been developed to synthesize tri- and pentapeptide thioesters containing one or more p-(hydroxyphenyl)glycine (pHPG) residues and L-serine, some where the latter is O-phosphorylated, O-acetylated, or exists as a β-lactam. Selection of orthogonal protection strategies and development of conditions to achieve seryl O-phosphorylation without β-elimination and to maintain stereochemical control, especially simultaneously at exceptionally base-labile pHPG α-carbons, are described. Intramolecular closure of a seryl peptide to a β-lactam-containing peptide and the syntheses of corresponding thioester analogues are also reported. Modification of classical Mitsunobu conditions is described in the synthesis of the β-lactam-containing products, and in a broadly useful observation, it was found that simple exclusion of light from the P(OEt)3-mediated Mitsunobu ring closure afforded yields of >95%, presumably owing to reduced photodegradation of the azodicarboxylate used. These sensitive potential substrates and products will be used in mechanistic studies of the two nonribosomal peptide synthetases NocA and NocB that lie at the heart of nocardicin biosynthesis, a family of monocyclic β-lactam antibiotics.
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Affiliation(s)
| | - Craig A. Townsend
- Department of Chemistry, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218
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