1
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Hou A, Dickschat JS. Labelling studies in the biosynthesis of polyketides and non-ribosomal peptides. Nat Prod Rep 2023; 40:470-499. [PMID: 36484402 DOI: 10.1039/d2np00071g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Covering: 2015 to 2022In this review, we discuss the recent advances in the use of isotopically labelled compounds to investigate the biosynthesis of polyketides, non-ribosomally synthesised peptides, and their hybrids. Also, we highlight the use of isotopes in the elucidation of their structures and investigation of enzyme mechanisms. The biosynthetic pathways of selected examples are presented in detail to reveal the principles of the discussed labelling experiments. The presented examples demonstrate that the application of isotopically labelled compounds is still the state of the art and can provide valuable information for the biosynthesis of natural products.
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Affiliation(s)
- Anwei Hou
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, West 7th Avenue No. 32, 300308 Tianjin, China.,Institute of Microbiology, Jiangxi Academy of Sciences, Changdong Road No. 7777, 330096 Nanchang, China
| | - Jeroen S Dickschat
- Kekulé-Institute for Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Straße 1, 53121 Bonn, Germany.
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2
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Becerril A, Pérez-Victoria I, Martín JM, Reyes F, Salas JA, Méndez C. Biosynthesis of Largimycins in Streptomyces argillaceus Involves Transient β-Alkylation and Cryptic Halogenation Steps Unprecedented in the Leinamycin Family. ACS Chem Biol 2022; 17:2320-2331. [PMID: 35830174 PMCID: PMC9396626 DOI: 10.1021/acschembio.2c00416] [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] [Indexed: 11/29/2022]
Abstract
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Largimycins A1 and A2 are key members of a recently identified
family of hybrid nonribosomal peptide polyketides belonging to the
scarcely represented group of antitumor leinamycins. They are encoded
by the gene cluster lrg of Streptomyces argillaceus. This cluster contains a halogenase gene and two sets of genes for
the biosynthesis and incorporation of β branches at C3 and C9.
Noticeably, largimycins A1 and A2 are nonhalogenated compounds and
only contain a β branch at C3. By generating mutants in those
genes and characterizing chemically their accumulated compounds, we
could confirm the existence of a chlorination step at C19, the introduction
of an acetyl-derived olefinic exomethylene group at C9, and a propionyl-derived
β branch at C3 in the biosynthesis pathway. Since the olefinic
exomethylene group and the chlorine atom are absent in the final products,
those biosynthetic steps can be considered cryptic in the overall
pathway but essential to generating keto and epoxide functionalities
at C9 and C18/C19, respectively. We propose that chlorination at C19
is utilized as an activation strategy that creates the precursor halohydrin
to finally yield the epoxy functionality at C18/C19. This represents
a novel strategy to create such functionalities and extends the small
number of natural product biosynthetic pathways that include a cryptic
chlorination step.
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Affiliation(s)
- Adriana Becerril
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, 33006 Oviedo, Spain.,Instituto de Investigación Sanitaria de Asturias (ISPA), 33011 Oviedo, Spain
| | - Ignacio Pérez-Victoria
- Fundación MEDINA, Centro de Excelencia en Investigación de Medicamentos Innovadores en Andalucía, Armilla, 18016 Granada, Spain
| | - Jesús M Martín
- Fundación MEDINA, Centro de Excelencia en Investigación de Medicamentos Innovadores en Andalucía, Armilla, 18016 Granada, Spain
| | - Fernando Reyes
- Fundación MEDINA, Centro de Excelencia en Investigación de Medicamentos Innovadores en Andalucía, Armilla, 18016 Granada, Spain
| | - Jose A Salas
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, 33006 Oviedo, Spain.,Instituto de Investigación Sanitaria de Asturias (ISPA), 33011 Oviedo, Spain
| | - Carmen Méndez
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, 33006 Oviedo, Spain.,Instituto de Investigación Sanitaria de Asturias (ISPA), 33011 Oviedo, Spain
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3
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Stunkard LM, Kick BJ, Lohman JR. Structures of LnmK, a Bifunctional Acyltransferase/Decarboxylase, with Substrate Analogues Reveal the Basis for Selectivity and Stereospecificity. Biochemistry 2021; 60:365-372. [PMID: 33482062 DOI: 10.1021/acs.biochem.0c00893] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
LnmK stereospecifically accepts (2R)-methylmalonyl-CoA, generating propionyl-S-acyl carrier protein to support polyketide biosynthesis. LnmK and its homologues are the only known enzymes that carry out a decarboxylation (DC) and acyl transfer (AT) reaction in the same active site as revealed by structure-function studies. Substrate-assisted catalysis powers LnmK, as decarboxylation of (2R)-methylmalonyl-CoA generates an enolate capable of deprotonating active site Tyr62, and the Tyr62 phenolate subsequently attacks propionyl-CoA leading to a propionyl-O-LnmK acyl-enzyme intermediate. Due to the inherent reactivity of LnmK and methylmalonyl-CoA, a substrate-bound structure could not be obtained. To gain insight into substrate specificity, stereospecificity, and catalytic mechanism, we determined the structures of LnmK with bound substrate analogues that bear malonyl-thioester isosteres where the carboxylate is represented by a nitro or sulfonate group. The nitro-bearing malonyl-thioester isosteres bind in the nitronate form, with specific hydrogen bonds that allow modeling of the (2R)-methylmalonyl-CoA substrate and rationalization of stereospecificity. The sulfonate isosteres bind in multiple conformations, suggesting the large active site of LnmK allows multiple binding modes. Considering the smaller malonyl group has more conformational freedom than the methylmalonyl group, we hypothesized the active site can entropically screen against catalysis with the smaller malonyl-CoA substrate. Indeed, our kinetic analysis reveals malonyl-CoA is accepted at 1% of the rate of methylmalonyl-CoA. This study represents another example of how our nitro- and sulfonate-bearing methylmalonyl-thioester isosteres are of use for elucidating enzyme-substrate binding interactions and revealing insights into catalytic mechanism. Synthesis of a larger panel of analogues presents an opportunity to study enzymes with complicated structure-function relationships such as acyl-CoA carboxylases, trans-carboxytransferases, malonyltransferases, and β-ketoacylsynthases.
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Affiliation(s)
- Lee M Stunkard
- Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Benjamin J Kick
- Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Jeremy R Lohman
- Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907, United States.,Purdue Center for Cancer Research, Purdue University, West Lafayette, Indiana 47907, United States
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4
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Walker PD, Weir ANM, Willis CL, Crump MP. Polyketide β-branching: diversity, mechanism and selectivity. Nat Prod Rep 2021; 38:723-756. [PMID: 33057534 DOI: 10.1039/d0np00045k] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Covering: 2008 to August 2020 Polyketides are a family of natural products constructed from simple building blocks to generate a diverse range of often complex chemical structures with biological activities of both pharmaceutical and agrochemical importance. Their biosynthesis is controlled by polyketide synthases (PKSs) which catalyse the condensation of thioesters to assemble a functionalised linear carbon chain. Alkyl-branches may be installed at the nucleophilic α- or electrophilic β-carbon of the growing chain. Polyketide β-branching is a fascinating biosynthetic modification that allows for the conversion of a β-ketone into a β-alkyl group or functionalised side-chain. The overall transformation is catalysed by a multi-protein 3-hydroxy-3-methylglutaryl synthase (HMGS) cassette and is reminiscent of the mevalonate pathway in terpene biosynthesis. The first step most commonly involves the aldol addition of acetate to the electrophilic carbon of the β-ketothioester catalysed by a 3-hydroxy-3-methylglutaryl synthase (HMGS). Subsequent dehydration and decarboxylation selectively generates either α,β- or β,γ-unsaturated β-alkyl branches which may be further modified. This review covers 2008 to August 2020 and summarises the diversity of β-branch incorporation and the mechanistic details of each catalytic step. This is extended to discussion of polyketides containing multiple β-branches and the selectivity exerted by the PKS to ensure β-branching fidelity. Finally, the application of HMGS in data mining, additional β-branching mechanisms and current knowledge of the role of β-branches in this important class of biologically active natural products is discussed.
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Affiliation(s)
- P D Walker
- Institute of Metabolism and Systems Research, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - A N M Weir
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
| | - C L Willis
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
| | - M P Crump
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
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5
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Lohman JR, Shen B. The LnmK Bifunctional Acyltransferase/Decarboxylase Specifying (2 R)-Methylmalonyl-CoA and Employing Substrate-Assisted Catalysis for Polyketide Biosynthesis. Biochemistry 2020; 59:4143-4147. [PMID: 33095002 DOI: 10.1021/acs.biochem.0c00749] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
We previously showed that the bifunctional LnmK acyltransferase/decarboxylase (AT/DC) catalyzed the formation of a propionyl-S-acyl carrier protein (ACP) from methylmalonyl-CoA, but its substrate specificity to (2S)-, (2R)-, or (2RS)-methylmalonyl CoA was not known. We subsequently revealed that LnmK AT and DC activities share the same active site, employing a Tyr as the catalytic residue for AT, but failed to identify a general base within the vicinity of the active site for LnmK catalysis. We now show that (i) LnmK specifies (2R)-methylmalonyl-CoA and (ii) the AT and DC activities are coupled, featuring substrate-assisted catalysis via the enolate to account for the missing general base within the LnmK active site. LnmK and its homologues are the only bifunctional AT/DC enzymes known to date and are widespread. These findings, therefore, enrich PKS chemistry and enzymology. Since only the (2S)-methylmalonyl-CoA enantiomer has been established previously as a substrate for polyketide biosynthesis by PKSs, we now establish a role for both (2R)- and (2S)-methylmalonyl-CoA in polyketide biosynthesis, and (2R)-methylmalonyl-CoA should be considered as a substrate in future efforts for engineered production of polyketides by combinatorial biosynthesis or synthetic biology strategies in model hosts.
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Affiliation(s)
- Jeremy R Lohman
- Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907, United States
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6
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Wan X, Yao G, Liu Y, Chen J, Jiang H. Research Progress in the Biosynthetic Mechanisms of Marine Polyether Toxins. Mar Drugs 2019; 17:E594. [PMID: 31652489 PMCID: PMC6835853 DOI: 10.3390/md17100594] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 10/17/2019] [Accepted: 10/18/2019] [Indexed: 12/28/2022] Open
Abstract
Marine polyether toxins, mainly produced by marine dinoflagellates, are novel, complex, and diverse natural products with extensive toxicological and pharmacological effects. Owing to their harmful effects during outbreaks of marine red tides, as well as their potential value for the development of new drugs, marine polyether toxins have been extensively studied, in terms of toxicology, pharmacology, detection, and analysis, structural identification, as well as their biosynthetic mechanisms. Although the biosynthetic mechanisms of marine polyether toxins are still unclear, certain progress has been made. In this review, research progress and current knowledge on the biosynthetic mechanisms of polyether toxins are summarized, including the mechanisms of carbon skeleton deletion, pendant alkylation, and polyether ring formation, along with providing a summary of mined biosynthesis-related genes. Finally, future research directions and applications of marine polyether toxins are discussed.
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Affiliation(s)
- Xiukun Wan
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China.
| | - Ge Yao
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China.
| | - Yanli Liu
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China.
| | - Jisheng Chen
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China.
| | - Hui Jiang
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China.
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7
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Liang H, Jiang L, Jiang Q, Shi J, Xiang J, Yan X, Zhu X, Zhao L, Shen B, Duan Y, Huang Y. A 3‐hydroxy‐3‐methylglutaryl‐CoA synthase‐based probe for the discovery of the acyltransferase‐less type I polyketide synthases. Environ Microbiol 2019; 21:4270-4282. [DOI: 10.1111/1462-2920.14787] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 08/08/2019] [Accepted: 08/20/2019] [Indexed: 11/28/2022]
Affiliation(s)
- Haoyu Liang
- Xiangya International Academy of Translational Medicine at Central South University Changsha Hunan China
| | - Lin Jiang
- Xiangya International Academy of Translational Medicine at Central South University Changsha Hunan China
| | - Qiyun Jiang
- School of Geosciences and Info‐physics at Central South University Changsha Hunan China
| | - Jie Shi
- Xiangya International Academy of Translational Medicine at Central South University Changsha Hunan China
| | - Jingxi Xiang
- Xiangya International Academy of Translational Medicine at Central South University Changsha Hunan China
| | - Xiaohui Yan
- Xiangya International Academy of Translational Medicine at Central South University Changsha Hunan China
- National Engineering Research Center of Combinatorial Biosynthesis for Drug Discovery Changsha Hunan China
| | - Xiangcheng Zhu
- Xiangya International Academy of Translational Medicine at Central South University Changsha Hunan China
- National Engineering Research Center of Combinatorial Biosynthesis for Drug Discovery Changsha Hunan China
- Hunan Engineering Research Center of Combinatorial Biosynthesis and Natural Product Drug Discovery Changsha Hunan China
| | - Lixing Zhao
- Yunnan Institute of Microbiology, Yunnan University Kunming Yunnan China
| | - Ben Shen
- Department of Chemistry The Scripps Research Institute Jupiter FL USA
- Molecular Medicine The Scripps Research Institute Jupiter FL USA
- Natural Products Library Initiative at The Scripps Research Institute, The Scripps Research Institute Jupiter FL USA
| | - Yanwen Duan
- Xiangya International Academy of Translational Medicine at Central South University Changsha Hunan China
- National Engineering Research Center of Combinatorial Biosynthesis for Drug Discovery Changsha Hunan China
- Hunan Engineering Research Center of Combinatorial Biosynthesis and Natural Product Drug Discovery Changsha Hunan China
| | - Yong Huang
- Xiangya International Academy of Translational Medicine at Central South University Changsha Hunan China
- National Engineering Research Center of Combinatorial Biosynthesis for Drug Discovery Changsha Hunan China
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8
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Kosol S, Jenner M, Lewandowski JR, Challis GL. Protein-protein interactions in trans-AT polyketide synthases. Nat Prod Rep 2019; 35:1097-1109. [PMID: 30280735 DOI: 10.1039/c8np00066b] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Covering: up to 2018 The construction of polyketide natural products by type I modular polyketide synthases (PKSs) requires the coordinated action of several protein subunits to ensure biosynthetic fidelity. This is particularly the case for trans-AT PKSs, which in contrast to most cis-AT PKSs, contain split modules and employ several trans-acting catalytic domains. This article summarises recent advances in understanding the protein-protein interactions underpinning subunit assembly and intra-subunit communication in such systems and highlights potential avenues and approaches for future research.
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Affiliation(s)
- Simone Kosol
- Department of Chemistry, University of Warwick, Coventry, CV4 7AL, UK.
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9
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Sato K, Katsuyama Y, Yokota K, Awakawa T, Tezuka T, Ohnishi Y. Involvement of β‐Alkylation Machinery and Two Sets of Ketosynthase‐Chain‐Length Factors in the Biosynthesis of Fogacin Polyketides in
Actinoplanes missouriensis. Chembiochem 2019; 20:1039-1050. [DOI: 10.1002/cbic.201800640] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Indexed: 11/12/2022]
Affiliation(s)
- Kei Sato
- Department of BiotechnologyGraduate School of Agricultural and Life SciencesThe University of Tokyo 1-1-1 Yayoi Bunkyo-ku Tokyo 113-8657 Japan
| | - Yohei Katsuyama
- Department of BiotechnologyGraduate School of Agricultural and Life SciencesThe University of Tokyo 1-1-1 Yayoi Bunkyo-ku Tokyo 113-8657 Japan
- Collaborative Research Institute for Innovative MicrobiologyThe University of Tokyo 1-1-1 Yayoi Bunkyo-ku Tokyo 113-8657 Japan
| | - Kousuke Yokota
- Department of BiotechnologyGraduate School of Agricultural and Life SciencesThe University of Tokyo 1-1-1 Yayoi Bunkyo-ku Tokyo 113-8657 Japan
| | - Takayoshi Awakawa
- Department of BiotechnologyGraduate School of Agricultural and Life SciencesThe University of Tokyo 1-1-1 Yayoi Bunkyo-ku Tokyo 113-8657 Japan
- Collaborative Research Institute for Innovative MicrobiologyThe University of Tokyo 1-1-1 Yayoi Bunkyo-ku Tokyo 113-8657 Japan
| | - Takeaki Tezuka
- Department of BiotechnologyGraduate School of Agricultural and Life SciencesThe University of Tokyo 1-1-1 Yayoi Bunkyo-ku Tokyo 113-8657 Japan
- Collaborative Research Institute for Innovative MicrobiologyThe University of Tokyo 1-1-1 Yayoi Bunkyo-ku Tokyo 113-8657 Japan
| | - Yasuo Ohnishi
- Department of BiotechnologyGraduate School of Agricultural and Life SciencesThe University of Tokyo 1-1-1 Yayoi Bunkyo-ku Tokyo 113-8657 Japan
- Collaborative Research Institute for Innovative MicrobiologyThe University of Tokyo 1-1-1 Yayoi Bunkyo-ku Tokyo 113-8657 Japan
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10
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Kwong T, Ma M, Pan G, Hindra, Yang D, Yang C, Lohman JR, Rudolf JD, Cleveland JL, Shen B. P450-Catalyzed Tailoring Steps in Leinamycin Biosynthesis Featuring Regio- and Stereoselective Hydroxylations and Substrate Promiscuities. Biochemistry 2018; 57:5005-5013. [PMID: 30070831 PMCID: PMC6211295 DOI: 10.1021/acs.biochem.8b00623] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Leinamycin (LNM) is a potent antitumor antibiotic produced by Streptomyces atroolivaceus S-140. Both in vivo and in vitro characterization of the LNM biosynthetic machinery have established the formation of the 18-membered macrolactam backbone and the C-3 alkyl branch; the nascent product, LNM E1, of the hybrid nonribosomal peptide synthetase (NRPS)-acyltransferase (AT)-less type I polyketide synthase (PKS); and the generation of the thiol moiety at C-3 of LNM E1. However, the tailoring steps converting LNM E1 to LNM are still unknown. Based on gene inactivation and chemical investigation of three mutant strains, we investigated the tailoring steps catalyzed by two cytochromes P450 (P450s), LnmA and LnmZ, in LNM biosynthesis. Our studies revealed that (i) LnmA and LnmZ regio- and stereoselectively hydroxylate the C-8 and C-4' positions, respectively, on the scaffold of LNM; (ii) both LnmA and LnmZ exhibit substrate promiscuity, resulting in multiple LNM analogs from several shunt pathways; and (iii) the C-8 and C-4' hydroxyl groups play important roles in the cytotoxicity of LNM analogs against different cancer cell lines, shedding light on the structure-activity relationships of the LNM scaffold and the LNM-type natural products in general. These studies set the stage for future biosynthetic pathway engineering and combinatorial biosynthesis of the LNM family of natural products for structure diversity and drug discovery.
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Affiliation(s)
| | - Ming Ma
- Department of Chemistry,United States
| | | | - Hindra
- Department of Chemistry,United States
| | - Dong Yang
- Department of Chemistry,United States
| | | | | | | | | | - Ben Shen
- Department of Chemistry,United States
- Department of Molecular Medicine,United States
- Natural Products Library Initiative at The Scripps Research Institute, The Scripps Research Institute, Jupiter, Florida 33458, United States
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11
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Discovery of the leinamycin family of natural products by mining actinobacterial genomes. Proc Natl Acad Sci U S A 2017; 114:E11131-E11140. [PMID: 29229819 DOI: 10.1073/pnas.1716245115] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Nature's ability to generate diverse natural products from simple building blocks has inspired combinatorial biosynthesis. The knowledge-based approach to combinatorial biosynthesis has allowed the production of designer analogs by rational metabolic pathway engineering. While successful, structural alterations are limited, with designer analogs often produced in compromised titers. The discovery-based approach to combinatorial biosynthesis complements the knowledge-based approach by exploring the vast combinatorial biosynthesis repertoire found in Nature. Here we showcase the discovery-based approach to combinatorial biosynthesis by targeting the domain of unknown function and cysteine lyase domain (DUF-SH) didomain, specific for sulfur incorporation from the leinamycin (LNM) biosynthetic machinery, to discover the LNM family of natural products. By mining bacterial genomes from public databases and the actinomycetes strain collection at The Scripps Research Institute, we discovered 49 potential producers that could be grouped into 18 distinct clades based on phylogenetic analysis of the DUF-SH didomains. Further analysis of the representative genomes from each of the clades identified 28 lnm-type gene clusters. Structural diversities encoded by the LNM-type biosynthetic machineries were predicted based on bioinformatics and confirmed by in vitro characterization of selected adenylation proteins and isolation and structural elucidation of the guangnanmycins and weishanmycins. These findings demonstrate the power of the discovery-based approach to combinatorial biosynthesis for natural product discovery and structural diversity and highlight Nature's rich biosynthetic repertoire. Comparative analysis of the LNM-type biosynthetic machineries provides outstanding opportunities to dissect Nature's biosynthetic strategies and apply these findings to combinatorial biosynthesis for natural product discovery and structural diversity.
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12
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Dunbar KL, Scharf DH, Litomska A, Hertweck C. Enzymatic Carbon-Sulfur Bond Formation in Natural Product Biosynthesis. Chem Rev 2017; 117:5521-5577. [PMID: 28418240 DOI: 10.1021/acs.chemrev.6b00697] [Citation(s) in RCA: 356] [Impact Index Per Article: 50.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Sulfur plays a critical role for the development and maintenance of life on earth, which is reflected by the wealth of primary metabolites, macromolecules, and cofactors bearing this element. Whereas a large body of knowledge has existed for sulfur trafficking in primary metabolism, the secondary metabolism involving sulfur has long been neglected. Yet, diverse sulfur functionalities have a major impact on the biological activities of natural products. Recent research at the genetic, biochemical, and chemical levels has unearthed a broad range of enzymes, sulfur shuttles, and chemical mechanisms for generating carbon-sulfur bonds. This Review will give the first systematic overview on enzymes catalyzing the formation of organosulfur natural products.
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Affiliation(s)
- Kyle L Dunbar
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI) , Beutenbergstrasse 11a, 07745 Jena, Germany
| | - Daniel H Scharf
- Life Sciences Institute, University of Michigan , 210 Washtenaw Avenue, Ann Arbor, Michigan 48109-2216, United States
| | - Agnieszka Litomska
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI) , Beutenbergstrasse 11a, 07745 Jena, Germany
| | - Christian Hertweck
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI) , Beutenbergstrasse 11a, 07745 Jena, Germany.,Friedrich Schiller University , 07743 Jena, Germany
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13
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Chen FM, Lu DD, Hu LQ, Huang J, Liu FS. Camphyl-based α-diimine palladium complexes: highly efficient precatalysts for direct arylation of thiazoles in open-air. Org Biomol Chem 2017; 15:5731-5736. [DOI: 10.1039/c7ob00856b] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Bulky camphyl-based α-diimine palladium complexes have been developed and exhibited high reactivity for the direct arylation of thiazoles in air.
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Affiliation(s)
- Fu-Min Chen
- School of Chemistry and Chemical Engineering
- Guangdong Cosmetics Engineering and Technology Research Center
- Guangdong Pharmaceutical University
- Zhongshan
- China
| | - Dong-Dong Lu
- School of Chemistry and Chemical Engineering
- Guangdong Cosmetics Engineering and Technology Research Center
- Guangdong Pharmaceutical University
- Zhongshan
- China
| | - Li-Qun Hu
- School of Chemistry and Chemical Engineering
- Guangdong Cosmetics Engineering and Technology Research Center
- Guangdong Pharmaceutical University
- Zhongshan
- China
| | - Ju Huang
- School of Chemistry and Chemical Engineering
- Guangdong Cosmetics Engineering and Technology Research Center
- Guangdong Pharmaceutical University
- Zhongshan
- China
| | - Feng-Shou Liu
- School of Chemistry and Chemical Engineering
- Guangdong Cosmetics Engineering and Technology Research Center
- Guangdong Pharmaceutical University
- Zhongshan
- China
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14
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Huang Y, Tang GL, Pan G, Chang CY, Shen B. Characterization of the Ketosynthase and Acyl Carrier Protein Domains at the LnmI Nonribosomal Peptide Synthetase-Polyketide Synthase Interface for Leinamycin Biosynthesis. Org Lett 2016; 18:4288-91. [PMID: 27541042 PMCID: PMC5013926 DOI: 10.1021/acs.orglett.6b02033] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Leinamycin (LNM) is biosynthesized by a hybrid nonribosomal peptide synthetase (NRPS)-acyltransferase (AT)-less type I polyketide synthase (PKS). Characterization of LnmI revealed ketosynthase (KS)-acyl carrier protein (ACP)-KS domains at the NRPS-PKS interface. Inactivation of the KS domain or ACP domain in vivo abolished LNM production, and the ACP domain can be phosphopantetheinylated in vitro. The LnmI KS-ACP-KS architecture represents a new mechanism for functional crosstalk between NRPS and AT-less type I PKS in the biosynthesis of hybrid peptide-polyketide natural products.
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Affiliation(s)
- Yong Huang
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Wisconsin , Madison, Wisconsin 53705, United States
| | - Gong-Li Tang
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Wisconsin , Madison, Wisconsin 53705, United States
| | | | | | - Ben Shen
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Wisconsin , Madison, Wisconsin 53705, United States
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15
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Helfrich EJN, Piel J. Biosynthesis of polyketides by trans-AT polyketide synthases. Nat Prod Rep 2016; 33:231-316. [DOI: 10.1039/c5np00125k] [Citation(s) in RCA: 230] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
This review discusses the biosynthesis of natural products that are generated bytrans-AT polyketide synthases, a family of catalytically versatile enzymes that represents one of the major group of proteins involved in the production of bioactive polyketides.
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Affiliation(s)
- Eric J. N. Helfrich
- Institute of Microbiology
- Eidgenössische Technische Hochschule (ETH) Zurich
- 8093 Zurich
- Switzerland
| | - Jörn Piel
- Institute of Microbiology
- Eidgenössische Technische Hochschule (ETH) Zurich
- 8093 Zurich
- Switzerland
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Abstract
Polyketides are a structurally and functionally diverse family of bioactive natural products that have found widespread application as pharmaceuticals, agrochemicals, and veterinary medicines. In bacteria complex polyketides are biosynthesized by giant multifunctional megaenzymes, termed modular polyketide synthases (PKSs), which construct their products in a highly coordinated assembly line-like fashion from a pool of simple precursor substrates. Not only is the multifaceted enzymology of PKSs a fascinating target for study, but it also presents considerable opportunities for the reengineering of these systems affording access to functionally optimized unnatural natural products. Here we provide an introductory primer to modular polyketide synthase structure and function, and highlight recent advances in the characterization and exploitation of these systems.
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Affiliation(s)
- Marisa Till
- School of Biochemistry, University of Bristol, Medical Sciences Building, University Walk, Bristol, BS8 1TD, UK
- BrisSynBio Synthetic Biology Research Centre, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol, BS8 1TQ, UK
| | - Paul R Race
- School of Biochemistry, University of Bristol, Medical Sciences Building, University Walk, Bristol, BS8 1TD, UK
- BrisSynBio Synthetic Biology Research Centre, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol, BS8 1TQ, UK
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17
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Liu T, Ma M, Ge HM, Yang C, Cleveland J, Shen B. Synthesis and evaluation of 8,4'-dideshydroxy-leinamycin revealing new insights into the structure-activity relationship of the anticancer natural product leinamycin. Bioorg Med Chem Lett 2015; 25:4899-4902. [PMID: 26071634 PMCID: PMC4607584 DOI: 10.1016/j.bmcl.2015.05.078] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 05/21/2015] [Indexed: 10/23/2022]
Abstract
Leinamycin (LNM, 1) is a novel antitumor antibiotic produced by Streptomyces atroolivaceus S-140 and features an unusual 1,3-dioxo-1,2-dithiolane moiety that is spiro-fused to a thiazole-containing 18-membered lactam ring. The 1,3-dioxo-1,2-dithiolane moiety of LNM is essential for its antitumor activity via an episulfonium ion-mediated DNA alkylation upon reductive activation in the presence of cellular thiols. We recently isolated leinamycin E1 (LNM E1, 2) from an engineered strain S. atroolivaceus SB3033, which lacks the 1,3-dioxo-1,2-dithiolane moiety. Here we report the chemical synthesis of 8,4'-dideshydroxy-LNM (5) from 2 and determination of the cytotoxicity of 5 against selected cancer cell lines in comparison with 1; 5 exhibits comparable activity as 1 with the EC50 values between 8.21 and 275 nM. This work reveals new insight into the structure-activity relationship of LNM and highlights the synergy between metabolic pathway engineering and medicinal chemistry for natural product drug discovery.
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Affiliation(s)
- Tao Liu
- Division of Pharmaceutical Sciences, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Ming Ma
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, #3A1, Jupiter, FL 33458, USA
| | - Hui-Ming Ge
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, #3A1, Jupiter, FL 33458, USA
| | - Chunying Yang
- Department of Cancer Biology, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - John Cleveland
- Department of Cancer Biology, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Ben Shen
- Division of Pharmaceutical Sciences, University of Wisconsin-Madison, Madison, WI 53705, USA; Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, #3A1, Jupiter, FL 33458, USA; Department of Molecular Therapeutics, The Scripps Research Institute, 130 Scripps Way, #3A1, Jupiter, FL 33458, USA; Natural Products Library Initiative, The Scripps Research Institute, 130 Scripps Way, #3A1, Jupiter, FL 33458, USA.
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18
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Abstract
Leinamycin (LNM) is a sulfur-containing antitumor antibiotic featuring an unusual 1,3-dioxo-1,2-dithiolane moiety that is spiro-fused to a thiazole-containing 18-membered lactam ring. The 1,3-dioxo-1,2-dithiolane moiety is essential for LNM's antitumor activity, by virtue of its ability to generate an episulfonium ion intermediate capable of alkylating DNA. We have previously cloned and sequenced the lnm gene cluster from Streptomyces atroolivaceus S-140. In vivo and in vitro characterizations of the LNM biosynthetic machinery have since established that: (i) the 18-membered macrolactam backbone is synthesized by LnmP, LnmQ, LnmJ, LnmI, and LnmG, (ii) the alkyl branch at C-3 of LNM is installed by LnmK, LnmL, LnmM, and LnmF, and (iii) leinamycin E1 (LNM E1), bearing a thiol moiety at C-3, is the nascent product of the LNM hybrid nonribosomal peptide synthetase (NRPS)-acyltransferase (AT)-less type I polyketide synthase (PKS). Sulfur incorporation at C-3 of LNM E1, however, has not been addressed. Here we report that: (i) the bioinformatics analysis reveals a pyridoxal phosphate (PLP)-dependent domain, we termed cysteine lyase (SH) domain (LnmJ-SH), within PKS module-8 of LnmJ; (ii) the LnmJ-SH domain catalyzes C-S bond cleavage by using l-cysteine and l-cysteine S-modified analogs as substrates through a PLP-dependent β-elimination reaction, establishing l-cysteine as the origin of sulfur at C-3 of LNM; and (iii) the LnmJ-SH domain, sharing no sequence homology with any other enzymes catalyzing C-S bond cleavage, represents a new family of PKS domains that expands the chemistry and enzymology of PKSs and might be exploited to incorporate sulfur into polyketide natural products by PKS engineering.
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19
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Leinamycin E1 acting as an anticancer prodrug activated by reactive oxygen species. Proc Natl Acad Sci U S A 2015; 112:8278-83. [PMID: 26056295 DOI: 10.1073/pnas.1506761112] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Leinamycin (LNM) is a potent antitumor antibiotic produced by Streptomyces atroolivaceus S-140, featuring an unusual 1,3-dioxo-1,2-dithiolane moiety that is spiro-fused to a thiazole-containing 18-membered lactam ring. Upon reductive activation in the presence of cellular thiols, LNM exerts its antitumor activity by an episulfonium ion-mediated DNA alkylation. Previously, we have cloned the lnm gene cluster from S. atroolivaceus S-140 and characterized the biosynthetic machinery responsible for the 18-membered lactam backbone and the alkyl branch at C3 of LNM. We now report the isolation and characterization of leinamycin E1 (LNM E1) from S. atroolivacues SB3033, a ΔlnmE mutant strain of S. atroolivaceus S-140. Complementary to the reductive activation of LNM by cellular thiols, LNM E1 can be oxidatively activated by cellular reactive oxygen species (ROS) to generate a similar episulfonium ion intermediate, thereby alkylating DNA and leading to eventual cell death. The feasibility of exploiting LNM E1 as an anticancer prodrug activated by ROS was demonstrated in two prostate cancer cell lines, LNCaP and DU-145. Because many cancer cells are under higher cellular oxidative stress with increased levels of ROS than normal cells, these findings support the idea of exploiting ROS as a means to target cancer cells and highlight LNM E1 as a novel lead for the development of anticancer prodrugs activated by ROS. The structure of LNM E1 also reveals critical new insights into LNM biosynthesis, setting the stage to investigate sulfur incorporation, as well as the tailoring steps that convert the nascent hybrid peptide-polyketide biosynthetic intermediate into LNM.
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Van Wagoner RM, Satake M, Wright JLC. Polyketide biosynthesis in dinoflagellates: what makes it different? Nat Prod Rep 2014; 31:1101-37. [DOI: 10.1039/c4np00016a] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Ye Z, Musiol EM, Weber T, Williams GJ. Reprogramming acyl carrier protein interactions of an Acyl-CoA promiscuous trans-acyltransferase. ACTA ACUST UNITED AC 2014; 21:636-46. [PMID: 24726832 DOI: 10.1016/j.chembiol.2014.02.019] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Revised: 01/27/2014] [Accepted: 02/06/2014] [Indexed: 11/29/2022]
Abstract
Protein interactions between acyl carrier proteins (ACPs) and trans-acting acyltransferase domains (trans-ATs) are critical for regioselective extender unit installation by many polyketide synthases, yet little is known regarding the specificity of these interactions, particularly for trans-ATs with unusual extender unit specificities. Currently, the best-studied trans-AT with nonmalonyl specificity is KirCII from kirromycin biosynthesis. Here, we developed an assay to probe ACP interactions based on leveraging the extender unit promiscuity of KirCII. The assay allows us to identify residues on the ACP surface that contribute to specific recognition by KirCII. This information proved sufficient to modify a noncognate ACP from a different biosynthetic system to be a substrate for KirCII. The findings form a foundation for further understanding the specificity of trans-AT:ACP protein interactions and for engineering modular polyketide synthases to produce analogs.
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Affiliation(s)
- Zhixia Ye
- Department of Chemistry, North Carolina State University, Raleigh, NC 27695-8204, USA
| | - Ewa M Musiol
- Interfaculty Institute of Microbiology and Infection Medicine, Eberhard Karls University of Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany; German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen, Germany
| | - Tilmann Weber
- Interfaculty Institute of Microbiology and Infection Medicine, Eberhard Karls University of Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany; German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen, Germany
| | - Gavin J Williams
- Department of Chemistry, North Carolina State University, Raleigh, NC 27695-8204, USA.
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22
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Waldman AJ, Balskus EP. Lomaiviticin biosynthesis employs a new strategy for starter unit generation. Org Lett 2014; 16:640-3. [PMID: 24383813 PMCID: PMC3965344 DOI: 10.1021/ol403714g] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Lomaiviticin biosynthesis is thought to utilize a propionyl starter unit for a type II polyketide synthase (PKS). Discovery of the lomaiviticin (lom) biosynthetic gene cluster suggested an unusual method for starter unit generation involving a bifunctional acyltransferase/decarboxylase (AT/DC) thus far observed only in type I PKS pathways. In vitro biochemical characterization of AT/DC Lom62 confirmed its ability to generate a propionyl-acyl carrier protein (ACP), revealing a new role for this enzymatic activity within natural product biosynthesis.
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Affiliation(s)
- Abraham J Waldman
- Department of Chemistry and Chemical Biology, Harvard University , Cambridge, Massachusetts 02138, United States
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Lohman JR, Bingman CA, Phillips GN, Shen B. Structure of the bifunctional acyltransferase/decarboxylase LnmK from the leinamycin biosynthetic pathway revealing novel activity for a double-hot-dog fold. Biochemistry 2013; 52:902-11. [PMID: 23320975 PMCID: PMC3567400 DOI: 10.1021/bi301652y] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The β-branched C3 unit in leinamycin biosynthesis is installed by a set of four proteins, LnmFKLM. In vitro biochemical investigation confirmed that LnmK is a bifunctional acyltransferase/decarboxylase (AT/DC) that catalyzes first self-acylation using methylmalonyl-CoA as a substrate and subsequently transacylation of the methylmalonyl group to the phosphopantetheinyl group of the LnmL acyl carrier protein [Liu, T., Huang, Y., and Shen, B. (2009) J. Am. Chem. Soc. 131, 6900-6901]. LnmK shows no sequence homology to proteins of known function, representing a new family of AT/DC enzymes. Here we report the X-ray structure of LnmK. LnmK is homodimer with each of the monomers adopting a double-hot-dog fold. Cocrystallization of LnmK with methylmalonyl-CoA revealed an active site tunnel terminated by residues from the dimer interface. In contrast to canonical AT and ketosynthase enzymes that employ Ser or Cys as an active site residue, none of these residues are found in the vicinity of the LnmK active site. Instead, three tyrosines were identified, one of which, Tyr62, was established, by site-directed mutagenesis, to be the most likely active site residue for the AT activity of LnmK. LnmK represents the first AT enzyme that employs a Tyr as an active site residue and the first member of the family of double-hot-dog fold enzymes that displays an AT activity known to date. The LnmK structure sets the stage for probing of the DC activity of LnmK through site-directed mutagenesis. These findings highlight natural product biosynthetic machinery as a rich source of novel enzyme activities, mechanisms, and structures.
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Affiliation(s)
- Jeremy R. Lohman
- Department of Chemistry The Scripps Research institute, Jupiter, Florida 33485
| | - Craig A. Bingman
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - George N. Phillips
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706
,Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77251
| | - Ben Shen
- Department of Chemistry The Scripps Research institute, Jupiter, Florida 33485
,Department of Molecular Therapeutics The Scripps Research institute, Jupiter, Florida 33485
,Department of Natural Products Library Initiative at The Scripps Research Institute, The Scripps Research institute, Jupiter, Florida 33485
,To whom correspondence should be addressed: The Scripps Research Institute, 130 Scripps Way, #3A1, Jupiter, FL 33458; Tel: (561) 228-2456; Fax: (561) 228-2472;
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24
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Musiol EM, Weber T. Discrete acyltransferases involved in polyketide biosynthesis. MEDCHEMCOMM 2012. [DOI: 10.1039/c2md20048a] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Gulder TAM, Freeman MF, Piel J. The Catalytic Diversity of Multimodular Polyketide Synthases: Natural Product Biosynthesis Beyond Textbook Assembly Rules. Top Curr Chem (Cham) 2011. [PMID: 21360321 DOI: 10.1007/128_2010_113] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Bacterial multimodular polyketide synthases (PKSs) are responsible for the biosynthesis of a wide range of pharmacologically active natural products. These megaenzymes contain numerous catalytic and structural domains and act as biochemical templates to generate complex polyketides in an assembly line-like fashion. While the prototypical PKS is composed of only a few different domain types that are fused together in a combinatorial fashion, an increasing number of enzymes is being found that contain additional components. These domains can introduce remarkably diverse modifications into polyketides. This review discusses our current understanding of such noncanonical domains and their role in expanding the biosynthetic versatility of bacterial PKSs.
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Buchholz TJ, Rath CM, Lopanik NB, Gardner NP, Håkansson K, Sherman DH. Polyketide β-branching in bryostatin biosynthesis: identification of surrogate acetyl-ACP donors for BryR, an HMG-ACP synthase. ACTA ACUST UNITED AC 2011; 17:1092-100. [PMID: 21035732 DOI: 10.1016/j.chembiol.2010.08.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2010] [Revised: 08/10/2010] [Accepted: 08/17/2010] [Indexed: 10/18/2022]
Abstract
In vitro analysis of natural product biosynthetic gene products isolated from unculturable symbiotic bacteria is necessary to probe the functionalities of these enzymes. Herein, we report the biochemical characterization of BryR, the 3-hydroxy-3-methylglutaryl (HMG)-CoA synthase (HMGS) homolog implicated in β-branching at C13 and C21 of the core ring system from the bryostatin metabolic pathway (Bry). We confirmed the activity of BryR using two complementary methods, radio-SDS PAGE, and Fourier transform ion cyclotron resonance-mass spectrometry (FTICR-MS). The activity of BryR depended on pairing of the native acetoacetyl-BryM3 acceptor acyl carrier protein (ACP) with an appropriate donor acetyl-ACP from a heterologous HMGS cassette. Additionally, the ability of BryR to discriminate between various ACPs was assessed using a surface plasmon resonance (SPR)-based protein-protein binding assay. Our data suggest that specificity for a protein-bound acyl group is a distinguishing feature between HMGS homologs found in PKS or PKS/NRPS biosynthetic pathways and those of primary metabolism. These findings reveal an important example of molecular recognition between protein components that are essential for biosynthetic fidelity in natural product assembly and modification.
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Affiliation(s)
- Tonia J Buchholz
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
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Huang Y, Huang SX, Ju J, Tang G, Liu T, Shen B. Characterization of the lnmKLM genes unveiling key intermediates for β-alkylation in leinamycin biosynthesis. Org Lett 2010; 13:498-501. [PMID: 21192727 DOI: 10.1021/ol102838y] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Leinamycin (LNM, 1) biosynthesis is proposed to involve β-alkylation of the polyketide intermediate, catalyzed by LnmKLM. Inactivation of lnmK, lnmL, or lnmM afforded mutant strains that accumulated LNM K-1 (2), K-2 (3), K-3 (4), and isomers LNM K-1' (5), K-2' (6), and K-3' (7) whose polyketide origin was established by feeding experiments with sodium [1-(13)C]acetate. These findings confirm the indispensability of LnmKLM in 1 biosynthesis and suggest that β-alkylation proceeds on the growing polyketide intermediate while bound to the LNM polyketide synthase.
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Affiliation(s)
- Yong Huang
- Division of Pharmaceutical Sciences, University of Wisconsin, Madison, Wisconsin 53705-2222, USA
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