1
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Zhu X, Wang R, Siitonen V, Vuksanovic N, Silvaggi NR, Melançon III CE, Metsä-Ketelä M. ActVI-ORFA directs metabolic flux towards actinorhodin by preventing intermediate degradation. PLoS One 2024; 19:e0308684. [PMID: 39121077 PMCID: PMC11315284 DOI: 10.1371/journal.pone.0308684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Accepted: 07/29/2024] [Indexed: 08/11/2024] Open
Abstract
The biosynthetic pathway of actinorhodin in Streptomyces coelicolor A3(2) has been studied for decades as a model system of type II polyketide biosynthesis. The actinorhodin biosynthetic gene cluster includes a gene, actVI-orfA, that encodes a protein that belongs to the nuclear transport factor-2-like (NTF-2-like) superfamily. The function of this ActVI-ORFA protein has been a long-standing question in this field. Several hypothetical functions, including pyran ring cyclase, enzyme complex stability enhancer, and gene transcription regulator, have been proposed for ActVI-ORFA in previous studies. However, although the recent structural analysis of ActVI-ORFA revealed a solvent-accessible cavity, the protein displayed structural differences to the well-characterized cyclase SnoaL and did not possess a DNA-binding domain. The obtained crystal structure facilitates an inspection of the previous hypotheses regarding the function of ActVI-ORFA. In the present study, we investigated the effects of a series of actVI-orfA test plasmids with different mutations in an established vector/host system. Time-course analysis of dynamic metabolism profiles demonstrated that ActVI-ORFA prevented formation of shunt metabolites and may have a metabolic flux directing function, which shepherds the flux of unstable intermediates towards actinorhodin. The expression studies resulted in the isolation and structure elucidation of two new shunt metabolites from the actinorhodin pathway. Next, we utilized computational modeling to probe the active site of ActVI-ORFA and confirmed the importance of residues R76 and H78 in the flux directing functionality by expression studies. This is the first time such a function has been observed for a member of NTF-2-like superfamily in Streptomyces secondary metabolism.
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Affiliation(s)
- Xuechen Zhu
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico, United States of America
| | - Rongbin Wang
- Department of Life Technologies, University of Turku, Turku, Finland
| | - Vilja Siitonen
- Department of Life Technologies, University of Turku, Turku, Finland
| | - Nemanja Vuksanovic
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, United States of America
| | - Nicholas R. Silvaggi
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, United States of America
| | - Charles E. Melançon III
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico, United States of America
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2
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Wang R, Nji Wandi B, Schwartz N, Hecht J, Ponomareva L, Paige K, West A, Desanti K, Nguyen J, Niemi J, Thorson JS, Shaaban KA, Metsä-Ketelä M, Nybo SE. Diverse Combinatorial Biosynthesis Strategies for C-H Functionalization of Anthracyclinones. ACS Synth Biol 2024; 13:1523-1536. [PMID: 38662967 PMCID: PMC11101304 DOI: 10.1021/acssynbio.4c00043] [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: 01/22/2024] [Revised: 04/11/2024] [Accepted: 04/16/2024] [Indexed: 05/18/2024]
Abstract
Streptomyces spp. are "nature's antibiotic factories" that produce valuable bioactive metabolites, such as the cytotoxic anthracycline polyketides. While the anthracyclines have hundreds of natural and chemically synthesized analogues, much of the chemical diversity stems from enzymatic modifications to the saccharide chains and, to a lesser extent, from alterations to the core scaffold. Previous work has resulted in the generation of a BioBricks synthetic biology toolbox in Streptomyces coelicolor M1152ΔmatAB that could produce aklavinone, 9-epi-aklavinone, auramycinone, and nogalamycinone. In this work, we extended the platform to generate oxidatively modified analogues via two crucial strategies. (i) We swapped the ketoreductase and first-ring cyclase enzymes for the aromatase cyclase from the mithramycin biosynthetic pathway in our polyketide synthase (PKS) cassettes to generate 2-hydroxylated analogues. (ii) Next, we engineered several multioxygenase cassettes to catalyze 11-hydroxylation, 1-hydroxylation, 10-hydroxylation, 10-decarboxylation, and 4-hydroxyl regioisomerization. We also developed improved plasmid vectors and S. coelicolor M1152ΔmatAB expression hosts to produce anthracyclinones. This work sets the stage for the combinatorial biosynthesis of bespoke anthracyclines using recombinant Streptomyces spp. hosts.
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Affiliation(s)
- Rongbin Wang
- Department
of Life Technologies, University of Turku, FIN-20014 Turku, Finland
| | - Benjamin Nji Wandi
- Department
of Life Technologies, University of Turku, FIN-20014 Turku, Finland
| | - Nora Schwartz
- Department
of Pharmaceutical Sciences, College of Pharmacy, Ferris State University, Big Rapids, Michigan 49307, United States
| | - Jacob Hecht
- Department
of Pharmaceutical Sciences, College of Pharmacy, Ferris State University, Big Rapids, Michigan 49307, United States
| | - Larissa Ponomareva
- Center
for Pharmaceutical Research and Innovation, Department of Pharmaceutical Sciences,
College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Kendall Paige
- Department
of Pharmaceutical Sciences, College of Pharmacy, Ferris State University, Big Rapids, Michigan 49307, United States
| | - Alexis West
- Department
of Pharmaceutical Sciences, College of Pharmacy, Ferris State University, Big Rapids, Michigan 49307, United States
| | - Kathryn Desanti
- Department
of Pharmaceutical Sciences, College of Pharmacy, Ferris State University, Big Rapids, Michigan 49307, United States
| | - Jennifer Nguyen
- Department
of Pharmaceutical Sciences, College of Pharmacy, Ferris State University, Big Rapids, Michigan 49307, United States
| | - Jarmo Niemi
- Department
of Life Technologies, University of Turku, FIN-20014 Turku, Finland
| | - Jon S. Thorson
- Center
for Pharmaceutical Research and Innovation, Department of Pharmaceutical Sciences,
College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Khaled A. Shaaban
- Center
for Pharmaceutical Research and Innovation, Department of Pharmaceutical Sciences,
College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Mikko Metsä-Ketelä
- Department
of Life Technologies, University of Turku, FIN-20014 Turku, Finland
| | - S. Eric Nybo
- Department
of Pharmaceutical Sciences, College of Pharmacy, Ferris State University, Big Rapids, Michigan 49307, United States
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3
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Pal P, Wessely SML, Townsend CA. Normal and Aberrant Methyltransferase Activities Give Insights into the Final Steps of Dynemicin A Biosynthesis. J Am Chem Soc 2023; 145:12935-12947. [PMID: 37276497 PMCID: PMC10985829 DOI: 10.1021/jacs.3c04393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The naturally occurring enediynes are notable for their complex structures, potent DNA cleaving ability, and emerging usefulness in cancer chemotherapy. They can be classified into three distinct structural families, but all are thought to originate from a common linear C15-heptaene. Dynemicin A (DYN) is the paradigm member of anthraquinone-fused enediynes, one of the three main classes and exceptional among them for derivation of both its enediyne and anthraquinone portions from this same early biosynthetic building block. Evidence is growing about how two structurally dissimilar, but biosynthetically related, intermediates combine in two heterodimerization reactions to create a nitrogen-containing C30-coupled product. We report here deletions of two genes that encode biosynthetic proteins that are annotated as S-adenosylmethionine (SAM)-dependent methyltransferases. While one, DynO6, is indeed the required O-methyltransferase implicated long ago in the first studies of DYN biosynthesis, the other, DynA5, functions in an unanticipated manner in the post-heterodimerization events that complete the biosynthesis of DYN. Despite its removal from the genome of Micromonospora chersina, the ΔdynA5 strain retains the ability to synthesize DYN, albeit in reduced titers, accompanied by two unusual co-metabolites. We link the appearance of these unexpected structures to a substantial and contradictory body of other recent experimental data to advance a biogenetic rationale for the downstream steps that lead to the final formation of DYN. A sequence of product-forming transformations that is in line with new and existing experimental results is proposed and supported by a model reaction that also encompasses the formation of the crucial epoxide essential for the activation of DYN for DNA cleavage.
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Affiliation(s)
- Paramita Pal
- Department of Chemistry, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland 21218, United States
| | - Serena M L Wessely
- Department of Chemistry, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland 21218, United States
| | - Craig A Townsend
- Department of Chemistry, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland 21218, United States
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4
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Xu Z, Tian P. Rethinking Biosynthesis of Aclacinomycin A. Molecules 2023; 28:molecules28062761. [PMID: 36985733 PMCID: PMC10054333 DOI: 10.3390/molecules28062761] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 03/01/2023] [Accepted: 03/06/2023] [Indexed: 03/22/2023] Open
Abstract
Aclacinomycin A (ACM-A) is an anthracycline antitumor agent widely used in clinical practice. The current industrial production of ACM-A relies primarily on chemical synthesis and microbial fermentation. However, chemical synthesis involves multiple reactions which give rise to high production costs and environmental pollution. Microbial fermentation is a sustainable strategy, yet the current fermentation yield is too low to satisfy market demand. Hence, strain improvement is highly desirable, and tremendous endeavors have been made to decipher biosynthesis pathways and modify key enzymes. In this review, we comprehensively describe the reported biosynthesis pathways, key enzymes, and, especially, catalytic mechanisms. In addition, we come up with strategies to uncover unknown enzymes and improve the activities of rate-limiting enzymes. Overall, this review aims to provide valuable insights for complete biosynthesis of ACM-A.
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5
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Wang R, Nguyen J, Hecht J, Schwartz N, Brown KV, Ponomareva LV, Niemczura M, van Dissel D, van Wezel GP, Thorson JS, Metsä-Ketelä M, Shaaban KA, Nybo SE. A BioBricks Metabolic Engineering Platform for the Biosynthesis of Anthracyclinones in Streptomyces coelicolor. ACS Synth Biol 2022; 11:4193-4209. [PMID: 36378506 PMCID: PMC9764417 DOI: 10.1021/acssynbio.2c00498] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Actinomycetes produce a variety of clinically indispensable molecules, such as antineoplastic anthracyclines. However, the actinomycetes are hindered in their further development as genetically engineered hosts for the synthesis of new anthracycline analogues due to their slow growth kinetics associated with their mycelial life cycle and the lack of a comprehensive genetic toolbox for combinatorial biosynthesis. In this report, we tackled both issues via the development of the BIOPOLYMER (BIOBricks POLYketide Metabolic EngineeRing) toolbox: a comprehensive synthetic biology toolbox consisting of engineered strains, promoters, vectors, and biosynthetic genes for the synthesis of anthracyclinones. An improved derivative of the production host Streptomyces coelicolor M1152 was created by deleting the matAB gene cluster that specifies extracellular poly-β-1,6-N-acetylglucosamine (PNAG). This resulted in a loss of mycelial aggregation, with improved biomass accumulation and anthracyclinone production. We then leveraged BIOPOLYMER to engineer four distinct anthracyclinone pathways, identifying optimal combinations of promoters, genes, and vectors to produce aklavinone, 9-epi-aklavinone, auramycinone, and nogalamycinone at titers between 15-20 mg/L. Optimization of nogalamycinone production strains resulted in titers of 103 mg/L. We structurally characterized six anthracyclinone products from fermentations, including new compounds 9,10-seco-7-deoxy-nogalamycinone and 4-O-β-d-glucosyl-nogalamycinone. Lastly, we tested the antiproliferative activity of the anthracyclinones in a mammalian cancer cell viability assay, in which nogalamycinone, auramycinone, and aklavinone exhibited moderate cytotoxicity against several cancer cell lines. We envision that BIOPOLYMER will serve as a foundational platform technology for the synthesis of designer anthracycline analogues.
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Affiliation(s)
- Rongbin Wang
- Department
of Life Technologies, University of Turku, FIN-20014 Turku, Finland
| | - Jennifer Nguyen
- Department
of Pharmaceutical Sciences, College of Pharmacy, Ferris State University, Big Rapids, Michigan 49307, United States
| | - Jacob Hecht
- Department
of Pharmaceutical Sciences, College of Pharmacy, Ferris State University, Big Rapids, Michigan 49307, United States
| | - Nora Schwartz
- Department
of Pharmaceutical Sciences, College of Pharmacy, Ferris State University, Big Rapids, Michigan 49307, United States
| | - Katelyn V. Brown
- Department
of Pharmaceutical Sciences, College of Pharmacy, Ferris State University, Big Rapids, Michigan 49307, United States
| | - Larissa V. Ponomareva
- §Center for Pharmaceutical
Research and Innovation, ∥Department of Pharmaceutical Sciences,
College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Magdalena Niemczura
- Department
of Life Technologies, University of Turku, FIN-20014 Turku, Finland
| | - Dino van Dissel
- Institute
of Biology, Leiden University, Sylviusweg 72, 2333
BE Leiden, The Netherlands,Department
of Biotechnology and Nanomedicine, SINTEF
AS, P.O. Box 4760 Torgarden, NO-7465 Trondheim, Norway
| | - Gilles P. van Wezel
- Institute
of Biology, Leiden University, Sylviusweg 72, 2333
BE Leiden, The Netherlands
| | - Jon S. Thorson
- §Center for Pharmaceutical
Research and Innovation, ∥Department of Pharmaceutical Sciences,
College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Mikko Metsä-Ketelä
- Department
of Life Technologies, University of Turku, FIN-20014 Turku, Finland,
| | - Khaled A. Shaaban
- §Center for Pharmaceutical
Research and Innovation, ∥Department of Pharmaceutical Sciences,
College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States,
| | - S. Eric Nybo
- Department
of Pharmaceutical Sciences, College of Pharmacy, Ferris State University, Big Rapids, Michigan 49307, United States,
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6
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Hulst MB, Grocholski T, Neefjes JJC, van Wezel GP, Metsä-Ketelä M. Anthracyclines: biosynthesis, engineering and clinical applications. Nat Prod Rep 2021; 39:814-841. [PMID: 34951423 DOI: 10.1039/d1np00059d] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Covering: January 1995 to June 2021Anthracyclines are glycosylated microbial natural products that harbour potent antiproliferative activities. Doxorubicin has been widely used as an anticancer agent in the clinic for several decades, but its use is restricted due to severe side-effects such as cardiotoxicity. Recent studies into the mode-of-action of anthracyclines have revealed that effective cardiotoxicity-free anthracyclines can be generated by focusing on histone eviction activity, instead of canonical topoisomerase II poisoning leading to double strand breaks in DNA. These developments have coincided with an increased understanding of the biosynthesis of anthracyclines, which has allowed generation of novel compound libraries by metabolic engineering and combinatorial biosynthesis. Coupled to the continued discovery of new congeners from rare Actinobacteria, a better understanding of the biology of Streptomyces and improved production methodologies, the stage is set for the development of novel anthracyclines that can finally surpass doxorubicin at the forefront of cancer chemotherapy.
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Affiliation(s)
- Mandy B Hulst
- Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands.
| | - Thadee Grocholski
- Department of Life Technologies, University of Turku, FIN-20014 Turku, Finland
| | - Jacques J C Neefjes
- Department of Cell and Chemical Biology and Oncode Institute, Leiden University Medical Centre, Leiden, The Netherlands
| | - Gilles P van Wezel
- Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands.
| | - Mikko Metsä-Ketelä
- Department of Life Technologies, University of Turku, FIN-20014 Turku, Finland
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7
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Tsutsumi H, Katsuyama Y, Tezuka T, Miyano R, Inahashi Y, Takahashi Y, Nakashima T, Ohnishi Y. Identification and Analysis of the Biosynthetic Gene Cluster for the Indolizidine Alkaloid Iminimycin in Streptomyces griseus. Chembiochem 2021; 23:e202100517. [PMID: 34767291 DOI: 10.1002/cbic.202100517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 10/27/2021] [Indexed: 11/06/2022]
Abstract
Indolizidine alkaloids, which have versatile bioactivities, are produced by various organisms. Although the biosynthesis of some indolizidine alkaloids has been studied, the enzymatic machinery for their biosynthesis in Streptomyces remains elusive. Here, we report the identification and analysis of the biosynthetic gene cluster for iminimycin, an indolizidine alkaloid with a 6-5-3 tricyclic system containing an iminium cation from Streptomyces griseus. The gene cluster has 22 genes, including four genes encoding polyketide synthases (PKSs), which consist of eight modules in total. In vitro analysis of the first module revealed that its acyltransferase domain selects malonyl-CoA, although predicted to select methylmalonyl-CoA. Inactivation of seven tailoring enzyme-encoding genes and structural elucidation of four compounds accumulated in mutants provided important insights into iminimycin biosynthesis, although some of these compounds appeared to be shunt products. This study expands our knowledge of the biosynthetic machinery of indolizidine alkaloids and the enzymatic chemistry of PKS.
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Affiliation(s)
- Hayama Tsutsumi
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Yohei Katsuyama
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.,Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Takeaki Tezuka
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.,Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Rei Miyano
- Graduate School of Infection Control Sciences, Kitasato University, 5-9-1, Minato-ku, Tokyo, 108-8641, Japan
| | - Yuki Inahashi
- Graduate School of Infection Control Sciences, Kitasato University, 5-9-1, Minato-ku, Tokyo, 108-8641, Japan.,Kitasato Institute for Life Sciences, Present: Ōmura Satoshi Memorial Institute), Kitasato University, 5-9-1, Minato-ku, Tokyo, 108-8641, Japan
| | - Yoko Takahashi
- Kitasato Institute for Life Sciences, Present: Ōmura Satoshi Memorial Institute), Kitasato University, 5-9-1, Minato-ku, Tokyo, 108-8641, Japan
| | - Takuji Nakashima
- Graduate School of Infection Control Sciences, Kitasato University, 5-9-1, Minato-ku, Tokyo, 108-8641, Japan.,Kitasato Institute for Life Sciences, Present: Ōmura Satoshi Memorial Institute), Kitasato University, 5-9-1, Minato-ku, Tokyo, 108-8641, Japan
| | - Yasuo Ohnishi
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.,Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
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8
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Fan S, Zhuang J, Guo C, Lin D, Liao X. 1H, 13C, 15N backbone and side-chain chemical shift assignments of the polyketide cyclase from Mycobacterium tuberculosis. BIOMOLECULAR NMR ASSIGNMENTS 2021; 15:397-402. [PMID: 34247331 DOI: 10.1007/s12104-021-10036-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 06/16/2021] [Indexed: 06/13/2023]
Abstract
Polyketide cyclase from Mycobacterium tuberculosis (MtPC) is related to the formation of sterol derivatives, which may play a role in immune escape in the initial stage of macrophage infection by Mycobacterium tuberculosis. However, the structure and specific functions of MtPC are still unknown. Here we report the backbone and side-chain NMR resonance assignments for the MtPC. Most resonances were assigned and the secondary structure was predicted according to the assigned backbone resonances by TALOS-N and PECAN. These NMR assignments represent a first step towards researching the structure and function of MtPC.
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Affiliation(s)
- Shihui Fan
- Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Jie Zhuang
- Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Chenyun Guo
- Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Donghai Lin
- Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China.
| | - Xinli Liao
- Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China.
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9
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Ma GL, Tran HT, Low ZJ, Candra H, Pang LM, Cheang QW, Fang M, Liang ZX. Pathway Retrofitting Yields Insights into the Biosynthesis of Anthraquinone-Fused Enediynes. J Am Chem Soc 2021; 143:11500-11509. [PMID: 34293863 DOI: 10.1021/jacs.1c03911] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Anthraquinone-fused enediynes (AQEs) are renowned for their distinctive molecular architecture, reactive enediyne warhead, and potent anticancer activity. Although the first members of AQEs, i.e., dynemicins, were discovered three decades ago, how their nitrogen-containing carbon skeleton is synthesized by microbial producers remains largely a mystery. In this study, we showed that the recently discovered sungeidine pathway is a "degenerative" AQE pathway that contains upstream enzymes for AQE biosynthesis. Retrofitting the sungeidine pathway with genes from the dynemicin pathway not only restored the biosynthesis of the AQE skeleton but also produced a series of novel compounds likely as the cycloaromatized derivatives of chemically unstable biosynthetic intermediates. The results suggest a cascade of highly surprising biosynthetic steps leading to the formation of the anthraquinone moiety, the hallmark C8-C9 linkage via alkyl-aryl cross-coupling, and the characteristic epoxide functionality. The findings provide unprecedented insights into the biosynthesis of AQEs and pave the way for examining these intriguing biosynthetic enzymes.
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Affiliation(s)
- Guang-Lei Ma
- School of Biological Sciences, Nanyang Technological University, Singapore 637551
| | - Hoa Thi Tran
- School of Biological Sciences, Nanyang Technological University, Singapore 637551
| | - Zhen Jie Low
- School of Biological Sciences, Nanyang Technological University, Singapore 637551
| | - Hartono Candra
- School of Biological Sciences, Nanyang Technological University, Singapore 637551
| | - Li Mei Pang
- School of Biological Sciences, Nanyang Technological University, Singapore 637551
| | - Qing Wei Cheang
- School of Biological Sciences, Nanyang Technological University, Singapore 637551
| | - Mingliang Fang
- School of Civil and Environmental Engineering, Nanyang Technological University, Singapore 639798
| | - Zhao-Xun Liang
- School of Biological Sciences, Nanyang Technological University, Singapore 637551
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10
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Cai X, Li C, Ichinose K, Jiang Y, Liu M, Wang H, Gong C, Li L, Wan J, Zhao Y, Yang Q, Li A. A single-domain small protein Med-ORF10 regulates the production of antitumour agent medermycin in Streptomyces. Microb Biotechnol 2021; 14:1918-1930. [PMID: 34139068 PMCID: PMC8449675 DOI: 10.1111/1751-7915.13834] [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: 01/29/2021] [Revised: 04/19/2021] [Accepted: 05/03/2021] [Indexed: 11/28/2022] Open
Abstract
Med-ORF10, a single-domain protein with unknown function encoded by a gene located in a gene cluster responsible for the biosynthesis of a novel antitumour antibiotic medermycin, shares high homology to a group of small proteins widely distributed in many aromatic polyketide antibiotic pathways. This group of proteins contain a nuclear transport factor-2 (NTF-2) domain and appear to undergo an evolutionary divergence in their functions. Gene knockout and interspecies complementation suggested that Med-ORF10 plays a regulatory role in medermycin biosynthetic pathway. Overexpression of med-ORF10 in its wild-type strain led to significant increase of medermycin production. It was also shown by qRT-PCR and Western blot that Med-ORF10 controls the expression of genes encoding tailoring enzymes involved in medermycin biosynthesis. Transcriptome analysis and qRT-PCR revealed that Med-ORF10 has pleiotropic effects on more targets. However, there is no similar conserved domain available in Med-ORF10 compared to those of mechanistically known regulatory proteins; meanwhile, no direct interaction between Med-ORF10 and its target promoter DNA was detected via gel shift assay. All these studies suggest that Med-ORF10 regulates medermycin biosynthesis probably via an indirect mode.
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Affiliation(s)
- Xiaofeng Cai
- Helmholtz International Lab for Anti-Infectives, Shandong University-Helmholtz Institute of Biotechnology, State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China.,The College of Life Sciences, Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, Central China Normal University, Wuhan, 430079, China.,School of Pharmacy, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Caiyun Li
- Helmholtz International Lab for Anti-Infectives, Shandong University-Helmholtz Institute of Biotechnology, State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China
| | - Koji Ichinose
- Research Institute of Pharmaceutical Sciences, Musashino University, Tokyo, 202-8585, Japan
| | - Yali Jiang
- The College of Life Sciences, Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, Central China Normal University, Wuhan, 430079, China
| | - Ming Liu
- The College of Life Sciences, Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, Central China Normal University, Wuhan, 430079, China
| | - Huili Wang
- The College of Life Sciences, Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, Central China Normal University, Wuhan, 430079, China
| | - Caixia Gong
- The College of Life Sciences, Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, Central China Normal University, Wuhan, 430079, China
| | - Le Li
- The College of Life Sciences, Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, Central China Normal University, Wuhan, 430079, China
| | - Juan Wan
- The College of Life Sciences, Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, Central China Normal University, Wuhan, 430079, China
| | - Yiming Zhao
- Helmholtz International Lab for Anti-Infectives, Shandong University-Helmholtz Institute of Biotechnology, State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China
| | - Qing Yang
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Songhu Road 2005, Shanghai, 200438, China
| | - Aiying Li
- Helmholtz International Lab for Anti-Infectives, Shandong University-Helmholtz Institute of Biotechnology, State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China.,The College of Life Sciences, Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, Central China Normal University, Wuhan, 430079, China
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11
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Jiang C, He BB, Zhao RL, Xu MJ, Houk KN, Zhao YL. Computational Exploration of How Enzyme XimE Converts Natural S-Epoxide to Pyran and R-Epoxide to Furan. ACS Catal 2021. [DOI: 10.1021/acscatal.1c01335] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Chuchu Jiang
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People’s Republic of China
| | - Bei-Bei He
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People’s Republic of China
| | - Rosalinda L. Zhao
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Min-Juan Xu
- Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Centre for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
| | - K. N. Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Yi-Lei Zhao
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People’s Republic of China
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12
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Bikash B, Vilja S, Mitchell L, Keith Y, Mikael I, Mikko MK, Jarmo N. Differential regulation of undecylprodigiosin biosynthesis in the yeast-scavenging Streptomyces strain MBK6. FEMS Microbiol Lett 2021; 368:6244240. [PMID: 33881506 PMCID: PMC8102152 DOI: 10.1093/femsle/fnab044] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 04/19/2021] [Indexed: 12/22/2022] Open
Abstract
Streptomyces are efficient chemists with a capacity to generate diverse and potent chemical scaffolds. The secondary metabolism of these soil-dwelling prokaryotes is stimulated upon interaction with other microbes in their complex ecosystem. We observed such an interaction when a Streptomyces isolate was cultivated in a media supplemented with dead yeast cells. Whole-genome analysis revealed that Streptomyces sp. MBK6 harbors the red cluster that is cryptic under normal environmental conditions. An interactive culture of MBK6 with dead yeast triggered the production of the red pigments metacycloprodigiosin and undecylprodigiosin. Streptomyces sp. MBK6 scavenges dead-yeast cells and preferentially grows in aggregates of sequestered yeasts within its mycelial network. We identified that the activation depends on the cluster-situated regulator, mbkZ, which may act as a cross-regulator. Cloning of this master regulator mbkZ in S. coelicolor with a constitutive promoter and promoter-deprived conditions generated different production levels of the red pigments. These surprising results were further validated by DNA–protein binding assays. The presence of the red cluster in Streptomyces sp. MBK6 provides a vivid example of horizontal gene transfer of an entire metabolic pathway followed by differential adaptation to a new environment through mutations in the receiver domain of the key regulatory protein MbkZ.
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Affiliation(s)
- Baral Bikash
- Department of Biotechnology, University of Turku, FIN-20014 Turku, Finland
| | - Siitonen Vilja
- Department of Biotechnology, University of Turku, FIN-20014 Turku, Finland
| | - Laughlin Mitchell
- Department of Biotechnology, University of Turku, FIN-20014 Turku, Finland
| | - Yamada Keith
- Department of Biotechnology, University of Turku, FIN-20014 Turku, Finland
| | - Ilomäki Mikael
- Department of Biotechnology, University of Turku, FIN-20014 Turku, Finland
| | - Metsä-Ketelä Mikko
- Department of Biotechnology, University of Turku, FIN-20014 Turku, Finland
| | - Niemi Jarmo
- Department of Biotechnology, University of Turku, FIN-20014 Turku, Finland
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13
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Quantitative Proteomics Analysis Reveals the Function of the Putative Ester Cyclase UvEC1 in the Pathogenicity of the Rice False Smut Fungus Ustilaginoidea virens. Int J Mol Sci 2021; 22:ijms22084069. [PMID: 33920773 PMCID: PMC8071170 DOI: 10.3390/ijms22084069] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 04/13/2021] [Accepted: 04/13/2021] [Indexed: 02/06/2023] Open
Abstract
Rice false smut is a fungal disease distributed worldwide and caused by Ustilaginoidea virens. In this study, we identified a putative ester cyclase (named as UvEC1) as being significantly upregulated during U. virens infection. UvEC1 contained a SnoaL-like polyketide cyclase domain, but the functions of ketone cyclases such as SnoaL in plant fungal pathogens remain unclear. Deletion of UvEC1 caused defects in vegetative growth and conidiation. UvEC1 was also required for response to hyperosmotic and oxidative stresses and for maintenance of cell wall integrity. Importantly, ΔUvEC1 mutants exhibited reduced virulence. We performed a tandem mass tag (TMT)-based quantitative proteomic analysis to identify differentially accumulating proteins (DAPs) between the ΔUvEC1-1 mutant and the wild-type isolate HWD-2. Proteomics data revealed that UvEC1 has a variety of effects on metabolism, protein localization, catalytic activity, binding, toxin biosynthesis and the spliceosome. Taken together, our findings suggest that UvEC1 is critical for the development and virulence of U. virens.
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14
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Nji Wandi B, Siitonen V, Dinis P, Vukic V, Salminen TA, Metsä-Ketelä M. Evolution-guided engineering of non-heme iron enzymes involved in nogalamycin biosynthesis. FEBS J 2020; 287:2998-3011. [PMID: 31876382 DOI: 10.1111/febs.15192] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 11/20/2019] [Accepted: 12/20/2019] [Indexed: 01/05/2023]
Abstract
Microbes are competent chemists that are able to generate thousands of chemically complex natural products with potent biological activities. The key to the formation of this chemical diversity has been the rapid evolution of secondary metabolism. Many enzymes residing on these metabolic pathways have acquired atypical catalytic properties in comparison with their counterparts found in primary metabolism. The biosynthetic pathway of the anthracycline nogalamycin contains two such proteins, SnoK and SnoN, belonging to nonheme iron and 2-oxoglutarate-dependent mono-oxygenases. In spite of structural similarity, the two proteins catalyze distinct chemical reactions; SnoK is a C2-C5″ carbocyclase, whereas SnoN catalyzes stereoinversion at the adjacent C4″ position. Here, we have identified four structural regions involved in the functional differentiation and generated 30 chimeric enzymes to probe catalysis. Our analyses indicate that the carbocyclase SnoK is the ancestral form of the enzyme from which SnoN has evolved to catalyze stereoinversion at the neighboring carbon. The critical step in the appearance of epimerization activity has likely been the insertion of three residues near the C-terminus, which allow repositioning of the substrate in front of the iron center. The loss of the original carbocyclization activity has then occurred with changes in four amino acids near the iron center that prohibit alignment of the substrate for the formation of the C2-C5″ bond. Our study provides detailed insights into the evolutionary processes that have enabled Streptomyces soil bacteria to become the major source of antibiotics and antiproliferative agents. ENZYMES: EC number 1.14.11.
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Affiliation(s)
| | - Vilja Siitonen
- Department of Biochemistry, University of Turku, Finland
| | - Pedro Dinis
- Department of Biochemistry, University of Turku, Finland
| | - Vladimir Vukic
- Structural Bioinformatics Laboratory, Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland.,Faculty of Technology Novi Sad, University of Novi Sad, Serbia
| | - Tiina A Salminen
- Structural Bioinformatics Laboratory, Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland
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15
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Fewer DP, Metsä‐Ketelä M. A pharmaceutical model for the molecular evolution of microbial natural products. FEBS J 2019; 287:1429-1449. [DOI: 10.1111/febs.15129] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 10/11/2019] [Accepted: 11/05/2019] [Indexed: 12/20/2022]
Affiliation(s)
- David P. Fewer
- Department of Microbiology University of Helsinki Finland
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16
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Drulyte I, Obajdin J, Trinh CH, Kalverda AP, van der Kamp MW, Hemsworth GR, Berry A. Crystal structure of the putative cyclase IdmH from the indanomycin nonribosomal peptide synthase/polyketide synthase. IUCRJ 2019; 6:1120-1133. [PMID: 31709067 PMCID: PMC6830212 DOI: 10.1107/s2052252519012399] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 09/05/2019] [Indexed: 05/08/2023]
Abstract
Indanomycin is biosynthesized by a hybrid nonribosomal peptide synthase/polyketide synthase (NRPS/PKS) followed by a number of 'tailoring' steps to form the two ring systems that are present in the mature product. It had previously been hypothesized that the indane ring of indanomycin was formed by the action of IdmH using a Diels-Alder reaction. Here, the crystal structure of a selenomethionine-labelled truncated form of IdmH (IdmH-Δ99-107) was solved using single-wavelength anomalous dispersion (SAD) phasing. This truncated variant allows consistent and easy crystallization, but importantly the structure was used as a search model in molecular replacement, allowing the full-length IdmH structure to be determined to 2.7 Å resolution. IdmH is a homodimer, with the individual protomers consisting of an α+β barrel. Each protomer contains a deep hydrophobic pocket which is proposed to constitute the active site of the enzyme. To investigate the reaction catalysed by IdmH, 88% of the backbone NMR resonances were assigned, and using chemical shift perturbation of [15N]-labelled IdmH it was demonstrated that indanomycin binds in the active-site pocket. Finally, combined quantum mechanical/molecular mechanical (QM/MM) modelling of the IdmH reaction shows that the active site of the enzyme provides an appropriate environment to promote indane-ring formation, supporting the assignment of IdmH as the key Diels-Alderase catalysing the final step in the biosynthesis of indanomycin through a similar mechanism to other recently characterized Diels-Alderases involved in polyketide-tailoring reactions. An animated Interactive 3D Complement (I3DC) is available in Proteopedia at https://proteopedia.org/w/Journal:IUCrJ:S2052252519012399.
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Affiliation(s)
- Ieva Drulyte
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, England
| | - Jana Obajdin
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, England
| | - Chi H. Trinh
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, England
| | - Arnout P. Kalverda
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, England
| | - Marc W. van der Kamp
- School of Biochemistry, University of Bristol, University Walk, Bristol BS8 1TD, England
| | - Glyn R. Hemsworth
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, England
| | - Alan Berry
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, England
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17
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Characterization and overproduction of cell-associated cholesterol oxidase ChoD from Streptomyces lavendulae YAKB-15. Sci Rep 2019; 9:11850. [PMID: 31413341 PMCID: PMC6694107 DOI: 10.1038/s41598-019-48132-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 07/25/2019] [Indexed: 11/30/2022] Open
Abstract
Cholesterol oxidases are important enzymes with a wide range of applications from basic research to industry. In this study, we have discovered and described the first cell-associated cholesterol oxidase, ChoD, from Streptomyces lavendulae YAKB-15. This strain is a naturally high producer of ChoD, but only produces ChoD in a complex medium containing whole yeast cells. For characterization of ChoD, we acquired a draft genome sequence of S. lavendulae YAKB-15 and identified a gene product containing a flavin adenine dinucleotide binding motif, which could be responsible for the ChoD activity. The enzymatic activity was confirmed in vitro with histidine tagged ChoD produced in Escherichia coli TOP10, which lead to the determination of basic kinetic parameters with Km 15.9 µM and kcat 10.4/s. The optimum temperature and pH was 65 °C and 5, respectively. In order to increase the efficiency of production, we then expressed the cholesterol oxidase, choD, gene heterologously in Streptomyces lividans TK24 and Streptomyces albus J1074 using two different expression systems. In S. albus J1074, the ChoD activity was comparable to the wild type S. lavendulae YAKB-15, but importantly allowed production of ChoD without the presence of yeast cells.
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18
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Grocholski T, Yamada K, Sinkkonen J, Tirkkonen H, Niemi J, Metsä-Ketelä M. Evolutionary Trajectories for the Functional Diversification of Anthracycline Methyltransferases. ACS Chem Biol 2019; 14:850-856. [PMID: 30995392 PMCID: PMC6750894 DOI: 10.1021/acschembio.9b00238] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Microbial natural
products are an important source of chemical
entities for drug discovery. Recent advances in understanding the
biosynthesis of secondary metabolites has revealed how this rich chemical
diversity is generated through functional differentiation of biosynthetic
enzymes. For instance, investigations into anthracycline anticancer
agents have uncovered distinct S-adenosyl methionine (SAM)-dependent
proteins: DnrK is a 4-O-methyltransferase involved in daunorubicin
biosynthesis, whereas RdmB (52% sequence identity) from the rhodomycin
pathway catalyzes 10-hydroxylation. Here, we have mined unknown anthracycline
gene clusters and discovered a third protein subclass catalyzing 10-decarboxylation.
Subsequent isolation of komodoquinone B from two Streptomyces strains verified the biological relevance of the decarboxylation
activity. Phylogenetic analysis inferred two independent routes for
the conversion of methyltransferases into hydroxylases, with a two-step
process involving loss-of-methylation and gain-of-hydroxylation presented
here. Finally, we show that simultaneously with the functional differentiation,
the evolutionary process has led to alterations in substrate specificities.
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19
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He BB, Zhou T, Bu XL, Weng JY, Xu J, Lin S, Zheng JT, Zhao YL, Xu MJ. Enzymatic Pyran Formation Involved in Xiamenmycin Biosynthesis. ACS Catal 2019. [DOI: 10.1021/acscatal.9b01034] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Bei-Bei He
- Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
| | - Ting Zhou
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
| | - Xu-Liang Bu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
| | - Jing-Yi Weng
- Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
| | - Jun Xu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
- School of Oceanography, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
| | - Shuangjun Lin
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
| | - Jian-Ting Zheng
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
| | - Yi-Lei Zhao
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
| | - Min-Juan Xu
- Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
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20
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Affiliation(s)
- Cheng Feng
- College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, P. R. China
| | - Qian Wei
- College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, P. R. China
| | - Changhua Hu
- College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, P. R. China
| | - Yi Zou
- College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, P. R. China
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21
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Siitonen V, Nji Wandi B, Törmänen AP, Metsä-Ketelä M. Enzymatic Synthesis of the C-Glycosidic Moiety of Nogalamycin R. ACS Chem Biol 2018; 13:2433-2437. [PMID: 30114358 PMCID: PMC6203184 DOI: 10.1021/acschembio.8b00658] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Carbohydrate moieties are essential for the biological activity of anthracycline anticancer agents such as nogalamycin, which contains l-nogalose and l-nogalamine units. The former of these is attached through a canonical O-glycosidic linkage, but the latter is connected via an unusual dual linkage composed of C-C and O-glycosidic bonds. In this work, we have utilized enzyme immobilization techniques and synthesized l-rhodosamine-thymidine diphosphate (TDP) from α-d-glucose-1-TDP using seven enzymes. In a second step, we assembled the dual linkage system by attaching the aminosugar to an anthracycline aglycone acceptor using the glycosyl transferase SnogD and the α-ketoglutarate dependent oxygenase SnoK. Furthermore, our work indicates that the auxiliary P450-type protein SnogN facilitating glycosylation is surprisingly associated with attachment of the neutral sugar l-nogalose rather than the aminosugar l-nogalamine in nogalamycin biosynthesis.
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Affiliation(s)
- Vilja Siitonen
- Department of Biochemistry, University of Turku, FIN-20014 Turku, Finland
| | - Benjamin Nji Wandi
- Department of Biochemistry, University of Turku, FIN-20014 Turku, Finland
| | | | - Mikko Metsä-Ketelä
- Department of Biochemistry, University of Turku, FIN-20014 Turku, Finland
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22
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Palmu K, Rosenqvist P, Thapa K, Ilina Y, Siitonen V, Baral B, Mäkinen J, Belogurov G, Virta P, Niemi J, Metsä-Ketelä M. Discovery of the Showdomycin Gene Cluster from Streptomyces showdoensis ATCC 15227 Yields Insight into the Biosynthetic Logic of C-Nucleoside Antibiotics. ACS Chem Biol 2017; 12:1472-1477. [PMID: 28418235 DOI: 10.1021/acschembio.7b00078] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Nucleoside antibiotics are a large class of pharmaceutically relevant chemical entities, which exhibit a broad spectrum of biological activities. Most nucleosides belong to the canonical N-nucleoside family, where the heterocyclic unit is connected to the carbohydrate through a carbon-nitrogen bond. However, atypical C-nucleosides were isolated from Streptomyces bacteria over 50 years ago, but the molecular basis for formation of these metabolites has been unknown. Here, we have sequenced the genome of S. showdoensis ATCC 15227 and identified the gene cluster responsible for showdomycin production. Key to the detection was the presence of sdmA, encoding an enzyme of the pseudouridine monophosphate glycosidase family, which could catalyze formation of the C-glycosidic bond. Sequence analysis revealed an unusual combination of biosynthetic genes, while inactivation and subsequent complementation of sdmA confirmed the involvement of the locus in showdomycin formation. The study provides the first steps toward generation of novel C-nucleosides by pathway engineering.
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Affiliation(s)
- Kaisa Palmu
- Departments
of Biochemistry and ‡Chemistry, University of Turku, FIN-20014 Turku, Finland
| | - Petja Rosenqvist
- Departments
of Biochemistry and ‡Chemistry, University of Turku, FIN-20014 Turku, Finland
| | - Keshav Thapa
- Departments
of Biochemistry and ‡Chemistry, University of Turku, FIN-20014 Turku, Finland
| | - Yulia Ilina
- Departments
of Biochemistry and ‡Chemistry, University of Turku, FIN-20014 Turku, Finland
| | - Vilja Siitonen
- Departments
of Biochemistry and ‡Chemistry, University of Turku, FIN-20014 Turku, Finland
| | - Bikash Baral
- Departments
of Biochemistry and ‡Chemistry, University of Turku, FIN-20014 Turku, Finland
| | - Janne Mäkinen
- Departments
of Biochemistry and ‡Chemistry, University of Turku, FIN-20014 Turku, Finland
| | - Georgi Belogurov
- Departments
of Biochemistry and ‡Chemistry, University of Turku, FIN-20014 Turku, Finland
| | - Pasi Virta
- Departments
of Biochemistry and ‡Chemistry, University of Turku, FIN-20014 Turku, Finland
| | - Jarmo Niemi
- Departments
of Biochemistry and ‡Chemistry, University of Turku, FIN-20014 Turku, Finland
| | - Mikko Metsä-Ketelä
- Departments
of Biochemistry and ‡Chemistry, University of Turku, FIN-20014 Turku, Finland
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23
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Structure and function of a broad-specificity chitin deacetylase from Aspergillus nidulans FGSC A4. Sci Rep 2017; 7:1746. [PMID: 28496100 PMCID: PMC5431758 DOI: 10.1038/s41598-017-02043-1] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 04/06/2017] [Indexed: 02/05/2023] Open
Abstract
Enzymatic conversion of chitin, a β-1,4 linked polymer of N-acetylglucosamine, is of major interest in areas varying from the biorefining of chitin-rich waste streams to understanding how medically relevant fungi remodel their chitin-containing cell walls. Although numerous chitinolytic enzymes have been studied in detail, relatively little is known about enzymes capable of deacetylating chitin. We describe the structural and functional characterization of a 237 residue deacetylase (AnCDA) from Aspergillus nidulans FGSC A4. AnCDA acts on chito-oligomers, crystalline chitin, chitosan, and acetylxylan, but not on peptidoglycan. The Km and kcat of AnCDA for the first deacetylation of penta-N-acetyl-chitopentaose are 72 µM and 1.4 s−1, respectively. Combining mass spectrometry and analyses of acetate release, it was shown that AnCDA catalyses mono-deacetylation of (GlcNAc)2 and full deacetylation of (GlcNAc)3–6 in a non-processive manner. Deacetylation of the reducing end sugar was much slower than deacetylation of the other sugars in chito-oligomers. These enzymatic characteristics are discussed in the light of the crystal structure of AnCDA, providing insight into how the chitin deacetylase may interact with its substrates. Interestingly, AnCDA activity on crystalline chitin was enhanced by a lytic polysaccharide monooxygenase that increases substrate accessibility by oxidative cleavage of the chitin chains.
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24
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Biochemical and Genetic Bases of Indole-3-Acetic Acid (Auxin Phytohormone) Degradation by the Plant-Growth-Promoting Rhizobacterium Paraburkholderia phytofirmans PsJN. Appl Environ Microbiol 2016; 83:AEM.01991-16. [PMID: 27795307 DOI: 10.1128/aem.01991-16] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 10/14/2016] [Indexed: 12/16/2022] Open
Abstract
Several bacteria use the plant hormone indole-3-acetic acid (IAA) as a sole carbon and energy source. A cluster of genes (named iac) encoding IAA degradation has been reported in Pseudomonas putida 1290, but the functions of these genes are not completely understood. The plant-growth-promoting rhizobacterium Paraburkholderia phytofirmans PsJN harbors iac gene homologues in its genome, but with a different gene organization and context than those of P. putida 1290. The iac gene functions enable P. phytofirmans to use IAA as a sole carbon and energy source. Employing a heterologous expression system approach, P. phytofirmans iac genes with previously undescribed functions were associated with specific biochemical steps. In addition, two uncharacterized genes, previously unreported in P. putida and found to be related to major facilitator and tautomerase superfamilies, are involved in removal of an IAA metabolite called dioxindole-3-acetate. Similar to the case in strain 1290, IAA degradation proceeds through catechol as intermediate, which is subsequently degraded by ortho-ring cleavage. A putative two-component regulatory system and a LysR-type regulator, which apparently respond to IAA and dioxindole-3-acetate, respectively, are involved in iac gene regulation in P. phytofirmans These results provide new insights about unknown gene functions and complex regulatory mechanisms in IAA bacterial catabolism. IMPORTANCE This study describes indole-3-acetic acid (auxin phytohormone) degradation in the well-known betaproteobacterium P. phytofirmans PsJN and comprises a complete description of genes, some of them with previously unreported functions, and the general basis of their gene regulation. This work contributes to the understanding of how beneficial bacteria interact with plants, helping them to grow and/or to resist environmental stresses, through a complex set of molecular signals, in this case through degradation of a highly relevant plant hormone.
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25
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Abstract
Nogalamycin, an aromatic polyketide displaying high cytotoxicity, has a unique structure, with one of the carbohydrate units covalently attached to the aglycone via an additional carbon-carbon bond. The underlying chemistry, which implies a particularly challenging reaction requiring activation of an aliphatic carbon atom, has remained enigmatic. Here, we show that the unusual C5''-C2 carbocyclization is catalyzed by the non-heme iron α-ketoglutarate (α-KG)-dependent SnoK in the biosynthesis of the anthracycline nogalamycin. The data are consistent with a mechanistic proposal whereby the Fe(IV) = O center abstracts the H5'' atom from the amino sugar of the substrate, with subsequent attack of the aromatic C2 carbon on the radical center. We further show that, in the same metabolic pathway, the homologous SnoN (38% sequence identity) catalyzes an epimerization step at the adjacent C4'' carbon, most likely via a radical mechanism involving the Fe(IV) = O center. SnoK and SnoN have surprisingly similar active site architectures considering the markedly different chemistries catalyzed by the enzymes. Structural studies reveal that the differences are achieved by minor changes in the alignment of the substrates in front of the reactive ferryl-oxo species. Our findings significantly expand the repertoire of reactions reported for this important protein family and provide an illustrative example of enzyme evolution.
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26
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Jackson DR, Yu X, Wang G, Patel AB, Calveras J, Barajas JF, Sasaki E, Metsä-Ketelä M, Liu HW, Rohr J, Tsai SC. Insights into Complex Oxidation during BE-7585A Biosynthesis: Structural Determination and Analysis of the Polyketide Monooxygenase BexE. ACS Chem Biol 2016; 11:1137-47. [PMID: 26813028 DOI: 10.1021/acschembio.5b00913] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Cores of aromatic polyketides are essential for their biological activities. Most type II polyketide synthases (PKSs) biosynthesize these core structures involving the minimal PKS, a PKS-associated ketoreductase (KR) and aromatases/cyclases (ARO/CYCs). Oxygenases (OXYs) are rarely involved. BE-7585A is an anticancer polyketide with an angucyclic core. (13)C isotope labeling experiments suggest that its angucyclic core may arise from an oxidative rearrangement of a linear anthracyclinone. Here, we present the crystal structure and functional analysis of BexE, the oxygenase proposed to catalyze this key oxidative rearrangement step that generates the angucyclinone framework. Biochemical assays using various linear anthracyclinone model compounds combined with docking simulations narrowed down the substrate of BexE to be an immediate precursor of aklaviketone, possibly 12-deoxy-aklaviketone. The structural analysis, docking simulations, and biochemical assays provide insights into the role of BexE in BE-7585A biosynthesis and lay the groundwork for engineering such framework-modifying enzymes in type II PKSs.
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Affiliation(s)
- David R. Jackson
- Department
of Molecular Biology and Biochemistry, Department of Chemistry, and
Department of Pharmaceutical Sciences, University of California, Irvine, California 92697, United States
| | - Xia Yu
- Department
of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Guojung Wang
- Department
of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Avinash B. Patel
- Department
of Molecular Biology and Biochemistry, Department of Chemistry, and
Department of Pharmaceutical Sciences, University of California, Irvine, California 92697, United States
| | - Jordi Calveras
- Division
of Medicinal Chemistry, College of Pharmacy and Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Jesus F. Barajas
- Department
of Molecular Biology and Biochemistry, Department of Chemistry, and
Department of Pharmaceutical Sciences, University of California, Irvine, California 92697, United States
| | - Eita Sasaki
- Division
of Medicinal Chemistry, College of Pharmacy and Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | | | - Hung-wen Liu
- Division
of Medicinal Chemistry, College of Pharmacy and Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Jürgen Rohr
- Department
of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Shiou-Chuan Tsai
- Department
of Molecular Biology and Biochemistry, Department of Chemistry, and
Department of Pharmaceutical Sciences, University of California, Irvine, California 92697, United States
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27
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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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28
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Grocholski T, Dinis P, Niiranen L, Niemi J, Metsä-Ketelä M. Divergent evolution of an atypical S-adenosyl-l-methionine-dependent monooxygenase involved in anthracycline biosynthesis. Proc Natl Acad Sci U S A 2015; 112:9866-71. [PMID: 26216966 PMCID: PMC4538628 DOI: 10.1073/pnas.1501765112] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bacterial secondary metabolic pathways are responsible for the biosynthesis of thousands of bioactive natural products. Many enzymes residing in these pathways have evolved to catalyze unusual chemical transformations, which is facilitated by an evolutionary pressure promoting chemical diversity. Such divergent enzyme evolution has been observed in S-adenosyl-L-methionine (SAM)-dependent methyltransferases involved in the biosynthesis of anthracycline anticancer antibiotics; whereas DnrK from the daunorubicin pathway is a canonical 4-O-methyltransferase, the closely related RdmB (52% sequence identity) from the rhodomycin pathways is an atypical 10-hydroxylase that requires SAM, a thiol reducing agent, and molecular oxygen for activity. Here, we have used extensive chimeragenesis to gain insight into the functional differentiation of RdmB and show that insertion of a single serine residue to DnrK is sufficient for introduction of the monooxygenation activity. The crystal structure of DnrK-Ser in complex with aclacinomycin T and S-adenosyl-L-homocysteine refined to 1.9-Å resolution revealed that the inserted serine S297 resides in an α-helical segment adjacent to the substrate, but in a manner where the side chain points away from the active site. Further experimental work indicated that the shift in activity is mediated by rotation of a preceding phenylalanine F296 toward the active site, which blocks a channel to the surface of the protein that is present in native DnrK. The channel is also closed in RdmB and may be important for monooxygenation in a solvent-free environment. Finally, we postulate that the hydroxylation ability of RdmB originates from a previously undetected 10-decarboxylation activity of DnrK.
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Affiliation(s)
- Thadée Grocholski
- Department of Biochemistry, University of Turku, FIN-20014 Turku, Finland
| | - Pedro Dinis
- Department of Biochemistry, University of Turku, FIN-20014 Turku, Finland
| | - Laila Niiranen
- Department of Biochemistry, University of Turku, FIN-20014 Turku, Finland
| | - Jarmo Niemi
- Department of Biochemistry, University of Turku, FIN-20014 Turku, Finland
| | - Mikko Metsä-Ketelä
- Department of Biochemistry, University of Turku, FIN-20014 Turku, Finland
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29
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Klymyshin DA, Stefanyshyn ON, Fedorenko VA. Role of genes snoaM, snoaL, and snoaE in the biosynthesis of nogalamycin in Streptomyces nogalater Lv65. CYTOL GENET+ 2015. [DOI: 10.3103/s0095452715030081] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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30
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Goswami A, Van Lanen SG. Enzymatic strategies and biocatalysts for amide bond formation: tricks of the trade outside of the ribosome. MOLECULAR BIOSYSTEMS 2015; 11:338-53. [PMID: 25418915 PMCID: PMC4304603 DOI: 10.1039/c4mb00627e] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Amide bond-containing (ABC) biomolecules are some of the most intriguing and functionally significant natural products with unmatched utility in medicine, agriculture and biotechnology. The enzymatic formation of an amide bond is therefore a particularly interesting platform for engineering the synthesis of structurally diverse natural and unnatural ABC molecules for applications in drug discovery and molecular design. As such, efforts to unravel the mechanisms involved in carboxylate activation and substrate selection has led to the characterization of a number of structurally and functionally distinct protein families involved in amide bond synthesis. Unlike ribosomal synthesis and thio-templated synthesis using nonribosomal peptide synthetases, which couple the hydrolysis of phosphoanhydride bond(s) of ATP and proceed via an acyl-adenylate intermediate, here we discuss two mechanistically alternative strategies: ATP-dependent enzymes that generate acylphosphate intermediates and ATP-independent transacylation strategies. Several examples highlighting the function and synthetic utility of these amide bond-forming strategies are provided.
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Affiliation(s)
- Anwesha Goswami
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 S. Limestone, Lexington, KY 40536, USA.
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31
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Patrikainen P, Niiranen L, Thapa K, Paananen P, Tähtinen P, Mäntsälä P, Niemi J, Metsä-Ketelä M. Structure-Based Engineering of Angucyclinone 6-Ketoreductases. ACTA ACUST UNITED AC 2014; 21:1381-1391. [DOI: 10.1016/j.chembiol.2014.07.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 07/24/2014] [Accepted: 07/25/2014] [Indexed: 11/27/2022]
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32
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Thapa K, Oja T, Metsä-Ketelä M. Molecular evolution of the bacterial pseudouridine-5′-phosphate glycosidase protein family. FEBS J 2014; 281:4439-49. [DOI: 10.1111/febs.12950] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 06/26/2014] [Accepted: 07/30/2014] [Indexed: 10/25/2022]
Affiliation(s)
- Keshav Thapa
- Department of Biochemistry; University of Turku; Finland
| | - Terhi Oja
- Department of Biochemistry; University of Turku; Finland
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33
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Yuan T, Xie L, Zhu B, Hu Y. Bioconversion of deoxysugar moieties to the biosynthetic intermediates of daunorubicin in an engineered strain of Streptomyces coeruleobidus. Biotechnol Lett 2014; 36:1809-18. [DOI: 10.1007/s10529-014-1542-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Accepted: 04/17/2014] [Indexed: 11/28/2022]
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34
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Paananen P, Patrikainen P, Kallio P, Mäntsälä P, Niemi J, Niiranen L, Metsä-Ketelä M. Structural and Functional Analysis of Angucycline C-6 Ketoreductase LanV Involved in Landomycin Biosynthesis. Biochemistry 2013; 52:5304-14. [DOI: 10.1021/bi400712q] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Pasi Paananen
- Department
of Biochemistry and Food Chemistry, University of Turku, FIN-20014 Turku, Finland
| | - Pekka Patrikainen
- Department
of Biochemistry and Food Chemistry, University of Turku, FIN-20014 Turku, Finland
| | - Pauli Kallio
- Department
of Biochemistry and Food Chemistry, University of Turku, FIN-20014 Turku, Finland
| | - Pekka Mäntsälä
- Department
of Biochemistry and Food Chemistry, University of Turku, FIN-20014 Turku, Finland
| | - Jarmo Niemi
- Department
of Biochemistry and Food Chemistry, University of Turku, FIN-20014 Turku, Finland
| | - Laila Niiranen
- Department
of Biochemistry and Food Chemistry, University of Turku, FIN-20014 Turku, Finland
| | - Mikko Metsä-Ketelä
- Department
of Biochemistry and Food Chemistry, University of Turku, FIN-20014 Turku, Finland
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35
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Valegård K, Iqbal A, Kershaw NJ, Ivison D, Généreux C, Dubus A, Blikstad C, Demetriades M, Hopkinson RJ, Lloyd AJ, Roper DI, Schofield CJ, Andersson I, McDonough MA. Structural and mechanistic studies of the orf12 gene product from the clavulanic acid biosynthesis pathway. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2013; 69:1567-79. [PMID: 23897479 DOI: 10.1107/s0907444913011013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Accepted: 04/23/2013] [Indexed: 11/10/2022]
Abstract
Structural and biochemical studies of the orf12 gene product (ORF12) from the clavulanic acid (CA) biosynthesis gene cluster are described. Sequence and crystallographic analyses reveal two domains: a C-terminal penicillin-binding protein (PBP)/β-lactamase-type fold with highest structural similarity to the class A β-lactamases fused to an N-terminal domain with a fold similar to steroid isomerases and polyketide cyclases. The C-terminal domain of ORF12 did not show β-lactamase or PBP activity for the substrates tested, but did show low-level esterase activity towards 3'-O-acetyl cephalosporins and a thioester substrate. Mutagenesis studies imply that Ser173, which is present in a conserved SXXK motif, acts as a nucleophile in catalysis, consistent with studies of related esterases, β-lactamases and D-Ala carboxypeptidases. Structures of wild-type ORF12 and of catalytic residue variants were obtained in complex with and in the absence of clavulanic acid. The role of ORF12 in clavulanic acid biosynthesis is unknown, but it may be involved in the epimerization of (3S,5S)-clavaminic acid to (3R,5R)-clavulanic acid.
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Affiliation(s)
- Karin Valegård
- Department of Molecular Biology, Swedish University of Agricultural Sciences, Box 590, S-751 24 Uppsala, Sweden
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36
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Kallio P, Patrikainen P, Belogurov GA, Mäntsälä P, Yang K, Niemi J, Metsä-Ketelä M. Tracing the evolution of angucyclinone monooxygenases: structural determinants for C-12b hydroxylation and substrate inhibition in PgaE. Biochemistry 2013; 52:4507-16. [PMID: 23731237 DOI: 10.1021/bi400381s] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Two functionally distinct homologous flavoprotein hydroxylases, PgaE and JadH, have been identified as branching points in the biosynthesis of the polyketide antibiotics gaudimycin C and jadomycin A, respectively. These evolutionarily related enzymes are both bifunctional and able to catalyze the same initial reaction, C-12 hydroxylation of the common angucyclinone intermediate prejadomycin. The enzymes diverge in their secondary activities, which include hydroxylation at C-12b by PgaE and dehydration at C-4a/C-12b by JadH. A further difference is that the C-12 hydroxylation is subject to substrate inhibition only in PgaE. Here we have identified regions associated with the C-12b hydroxylation in PgaE by extensive chimeragenesis, focusing on regions surrounding the active site. The results highlight the importance of a hairpin-β motif near the dimer interface, with two nonconserved residues, P78 and I79 (corresponding to Q89 and F90, respectively, in JadH), and invariant residue H73 playing key roles. Kinetic characterization of PgaE variants demonstrates that the secondary C-12b hydroxylation and substrate inhibition by prejadomycin are likely to be interlinked. The crystal structure of the PgaE P78Q/I79F variant at 2.4 Å resolution confirms that the changes do not alter the conformation of the β-strand secondary structure and that the side chains of these residues in effect point away from the active site toward the dimer interface. The results support a catalytic model for PgaE containing two binding modes for C-12 and C-12b hydroxylations, where binding of prejadomycin in the orientation for C-12b hydroxylation leads to substrate inhibition. The presence of an allosteric network is evident based on enzyme kinetics.
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Affiliation(s)
- Pauli Kallio
- Department of Biochemistry and Food Chemistry, University of Turku, FIN-20014 Turku, Finland
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37
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Structural basis for C-ribosylation in the alnumycin A biosynthetic pathway. Proc Natl Acad Sci U S A 2013; 110:1291-6. [PMID: 23297194 DOI: 10.1073/pnas.1207407110] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Alnumycin A is an exceptional aromatic polyketide that contains a carbohydrate-like 4'-hydroxy-5'-hydroxymethyl-2',7'-dioxane moiety attached to the aglycone via a carbon-carbon bond. Recently, we have identified the D-ribose-5-phosphate origin of the dioxane unit and demonstrated that AlnA and AlnB are responsible for the overall C-ribosylation reaction. Here, we provide direct evidence that AlnA is a natural C-glycosynthase, which catalyzes the attachment of D-ribose-5-phosphate to prealnumycin by formation of the C(8)-C(1') bond as demonstrated by the structure of the intermediate alnumycin P. This compound is subsequently dephosphorylated by AlnB, an enzyme of the haloacid dehalogenase superfamily. Structure determination of the native trimeric AlnA to 2.1-Å resolution revealed a highly globular fold encompassing an α/β/α sandwich. The crystal structure of the complex with D-ribose-5-phosphate indicated that the phosphosugar is bound in the open-chain configuration. Identification of residues E29, K86, and K159 near the C-1 carbonyl of the ligand led us to propose that the carbon-carbon bond formation proceeds through a Michael-type addition. Determination of the crystal structure of the monomeric AlnB in the open conformation to 1.25-Å resolution showed that the protein consists of core and cap domains. Modeling of alnumycin P inside the cap domain positioned the phosphate group next to a Mg(2+) ion present at the junction of the domains. Mutagenesis data were consistent with the canonical reaction mechanism for this enzyme family revealing the importance of residues D15 and D17 for catalysis. The characterization of the prealnumycin C-ribosylation illustrates an alternative means for attachment of carbohydrates to natural products.
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38
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Boronated tartrolon antibiotic produced by symbiotic cellulose-degrading bacteria in shipworm gills. Proc Natl Acad Sci U S A 2013; 110:E295-304. [PMID: 23288898 DOI: 10.1073/pnas.1213892110] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Shipworms are marine wood-boring bivalve mollusks (family Teredinidae) that harbor a community of closely related Gammaproteobacteria as intracellular endosymbionts in their gills. These symbionts have been proposed to assist the shipworm host in cellulose digestion and have been shown to play a role in nitrogen fixation. The genome of one strain of Teredinibacter turnerae, the first shipworm symbiont to be cultivated, was sequenced, revealing potential as a rich source of polyketides and nonribosomal peptides. Bioassay-guided fractionation led to the isolation and identification of two macrodioloide polyketides belonging to the tartrolon class. Both compounds were found to possess antibacterial properties, and the major compound was found to inhibit other shipworm symbiont strains and various pathogenic bacteria. The gene cluster responsible for the synthesis of these compounds was identified and characterized, and the ketosynthase domains were analyzed phylogenetically. Reverse-transcription PCR in addition to liquid chromatography and high-resolution mass spectrometry and tandem mass spectrometry revealed the transcription of these genes and the presence of the compounds in the shipworm, suggesting that the gene cluster is expressed in vivo and that the compounds may fulfill a specific function for the shipworm host. This study reports tartrolon polyketides from a shipworm symbiont and unveils the biosynthetic gene cluster of a member of this class of compounds, which might reveal the mechanism by which these bioactive metabolites are biosynthesized.
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39
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Patrikainen P, Kallio P, Fan K, Klika KD, Shaaban KA, Mäntsälä P, Rohr J, Yang K, Niemi J, Metsä-Ketelä M. Tailoring enzymes involved in the biosynthesis of angucyclines contain latent context-dependent catalytic activities. ACTA ACUST UNITED AC 2012; 19:647-55. [PMID: 22633416 DOI: 10.1016/j.chembiol.2012.04.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 03/07/2012] [Accepted: 04/04/2012] [Indexed: 10/28/2022]
Abstract
Comparison of homologous angucycline modification enzymes from five closely related Streptomyces pathways (pga, cab, jad, urd, lan) allowed us to deduce the biosynthetic steps responsible for the three alternative outcomes: gaudimycin C, dehydrorabelomycin, and 11-deoxylandomycinone. The C-12b-hydroxylated urdamycin and gaudimycin metabolites appear to be the ancestral representatives from which landomycins and jadomysins have evolved as a result of functional divergence of the ketoreductase LanV and hydroxylase JadH, respectively. Specifically, LanV has acquired affinity for an earlier biosynthetic intermediate resulting in a switch in biosynthetic order and lack of hydroxyls at C-4a and C-12b, whereas in JadH, C-4a/C-12b dehydration has evolved into an independent secondary function replacing C-12b hydroxylation. Importantly, the study reveals that many of the modification enzymes carry several alternative, hidden, or ancestral catalytic functions, which are strictly dependent on the biosynthetic context.
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Affiliation(s)
- Pekka Patrikainen
- Department of Biochemistry and Food Chemistry, University of Turku, 20014 Turku, Finland
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40
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Siitonen V, Blauenburg B, Kallio P, Mäntsälä P, Metsä-Ketelä M. Discovery of a Two-Component Monooxygenase SnoaW/SnoaL2 Involved in Nogalamycin Biosynthesis. ACTA ACUST UNITED AC 2012; 19:638-46. [DOI: 10.1016/j.chembiol.2012.04.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Revised: 03/16/2012] [Accepted: 04/04/2012] [Indexed: 11/30/2022]
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41
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Biosynthetic pathway toward carbohydrate-like moieties of alnumycins contains unusual steps for C-C bond formation and cleavage. Proc Natl Acad Sci U S A 2012; 109:6024-9. [PMID: 22474343 DOI: 10.1073/pnas.1201530109] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Carbohydrate moieties are important components of natural products, which are often imperative for the solubility and biological activity of the compounds. The aromatic polyketide alnumycin A contains an extraordinary sugar-like 4'-hydroxy-5'-hydroxymethyl-2',7'-dioxane moiety attached via a carbon-carbon bond to the aglycone. Here we have extensively investigated the biosynthesis of the dioxane unit through (13)C labeling studies, gene inactivation experiments and enzymatic synthesis. We show that AlnA and AlnB, members of the pseudouridine glycosidase and haloacid dehalogenase enzyme families, respectively, catalyze C-ribosylation conceivably through Michael-type addition of d-ribose-5-phosphate and dephosphorylation. The ribose moiety may be attached both in furanose (alnumycin C) and pyranose (alnumycin D) forms. The C(1')-C(2') bond of alnumycin C is subsequently cleaved and the ribose unit is rearranged into an unprecedented dioxolane (cis-bicyclo[3.3.0]-2',4',6'-trioxaoctan-3'β-ol) structure present in alnumycin B. The reaction is catalyzed by Aln6, which belongs to a previously uncharacterized enzyme family. The conversion was accompanied with consumption of O(2) and formation of H(2)O(2), which allowed us to propose that the reaction may proceed via hydroxylation of C1' followed by retro-aldol cleavage and acetal formation. Interestingly, no cofactors could be detected and the reaction was also conducted in the presence of metal chelating agents. The last step is the conversion of alnumycin B into the final end-product alnumycin A catalyzed by Aln4, an NADPH-dependent aldo-keto reductase. This characterization of the dioxane biosynthetic pathway sets the basis for the utilization of C-C bound ribose, dioxolane and dioxane moieties in the generation of improved biologically active compounds.
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42
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Characterization of the two-component monooxygenase system AlnT/AlnH reveals early timing of quinone formation in alnumycin biosynthesis. J Bacteriol 2012; 194:2829-36. [PMID: 22467789 DOI: 10.1128/jb.00228-12] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Alnumycin A is an aromatic polyketide with a strong resemblance to related benzoisochromanequinone (BIQ) antibiotics, such as the model antibiotic actinorhodin. One intriguing difference between these metabolites is that the positions of the benzene and quinone rings are reversed in alnumycin A in comparison to the BIQ polyketides. In this paper we demonstrate that inactivation of either the monooxygenase alnT gene or the flavin reductase alnH gene results in the accumulation of a novel nonquinoid metabolite, thalnumycin A (ThA), in the culture medium. Additionally, two other previously characterized metabolites, K1115 A and 1,6-dihydroxy-8-propylanthraquinone (DHPA), were identified, which had oxidized into quinones putatively nonenzymatically at the incorrect position in the central ring. None of the compounds isolated contained correctly formed pyran rings, which suggests that on the alnumycin pathway quinone biosynthesis occurs prior to third ring cyclization. The regiochemistry of the two-component monooxygenase system AlnT/AlnH was finally confirmed in vitro by using ThA, FMN, and NADH in enzymatic synthesis, where the reaction product, thalnumycin B (ThB), was verified to contain the expected p-hydroquinone structure in the lateral ring.
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43
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Amrein B, Schmid M, Collet G, Cuniasse P, Gilardoni F, Seebeck FP, Ward TR. Identification of two-histidines one-carboxylate binding motifs in proteins amenable to facial coordination to metals. Metallomics 2012; 4:379-88. [DOI: 10.1039/c2mt20010d] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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44
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Kallio P, Patrikainen P, Suomela JP, Mäntsälä P, Metsä-Ketelä M, Niemi J. Flavoprotein hydroxylase PgaE catalyzes two consecutive oxygen-dependent tailoring reactions in angucycline biosynthesis. Biochemistry 2011; 50:5535-43. [PMID: 21595438 DOI: 10.1021/bi200600k] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A simplified model system composed of a NADPH-dependent flavoprotein hydroxylase PgaE and a short-chain alcohol dehydrogenase/reductase (SDR) CabV was used to dissect a multistep angucycline modification redox cascade into several subreactions in vitro. We demonstrate that the two enzymes are sufficient for the conversion of angucycline substrate 2,3-dehydro-UWM6 to gaudimycin C. The flavoenzyme PgaE is shown to be responsible for two consecutive NADPH- and O(2)-dependent reactions, consistent with the enzyme-catalyzed incorporation of oxygen atoms at C-12 and C-12b in gaudimycin C. The two reactions do not significantly overlap, and the second catalytic cycle is initiated only after the original substrate 2,3-dehydro-UWM6 is nearly depleted. This allowed us to isolate the product of the first reaction at limiting NADPH concentrations and allowed the study of the qualitative and kinetic properties of the separated reactions. Dissection of the reaction cascade also allowed us to establish that the SDR reductase CabV catalyzes the final biosynthetic step, which is closely coupled to the second PgaE reaction. In the absence of CabV, the complete PgaE reaction leads invariably to product degradation, whereas in its presence, the reaction yields the final product, gaudimycin C. The result implies that the C-6 ketoreduction step catalyzed by CabV is required for stabilization of a reactive intermediate. The close relationship between PgaE and CabV would explain previous in vivo observations: why the absence of a reductase gene may result in the lack of C-12b-oxygenated species and, vice versa, why all C-12b-oxygenated angucyclines appear to have undergone reduction at position C-6.
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Affiliation(s)
- Pauli Kallio
- Department of Biochemistry and Food Chemistry, University of Turku, FIN-20014 Turku, Finland
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Crystal structure of γ-hexachlorocyclohexane Dehydrochlorinase LinA from Sphingobium japonicum UT26. J Mol Biol 2010; 403:260-9. [PMID: 20813114 DOI: 10.1016/j.jmb.2010.08.043] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2010] [Revised: 08/19/2010] [Accepted: 08/23/2010] [Indexed: 10/19/2022]
Abstract
LinA from Sphingobium japonicum UT26 catalyzes two steps of dehydrochlorination from γ hexachlorocyclohexane (HCH) to 1,3,4,6-tetrachloro-1,4-cyclohexadiene via γ-pentachlorocyclohexene. We determined the crystal structure of LinA at 2.25 Å by single anomalous dispersion. LinA exists as a homotrimer, and each protomer forms a cone-shaped α+β barrel fold. The C-terminal region of LinA is extended to the neighboring subunit, unlike that of scytalone dehydratase from Magnaporthe grisea, which is one of the most structurally similar proteins identified by the DALI server. The structure we obtained in this study is in open form, in which γ-HCH can enter the active site. There is a hydrophobic cavity inside the barrel fold, and the active site is largely surrounded by the side chains of K20, L21, V24, D25, W42, L64, F68, C71, H73, V94, L96, I109, F113, and R129. H73 was considered to function as a base that abstracts the proton of γ-HCH through its interaction with D25. Docking simulations with γ-HCH and γ-pentachlorocyclohexene suggest that 11 residues (K20, I44, L64, V94, L96, I109, A111, F113, A131, C132, and T133) are involved in the binding of these compounds and support the degradation mechanism.
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Zhou H, Li Y, Tang Y. Cyclization of aromatic polyketides from bacteria and fungi. Nat Prod Rep 2010; 27:839-68. [PMID: 20358042 DOI: 10.1039/b911518h] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Hui Zhou
- Department of Chemical and Biomolecular Engineering, University of California, Los Angles, 420 Westwood Plaza, Los Angeles, CA 90095, USA
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Olano C, Méndez C, Salas JA. Post-PKS tailoring steps in natural product-producing actinomycetes from the perspective of combinatorial biosynthesis. Nat Prod Rep 2010; 27:571-616. [DOI: 10.1039/b911956f] [Citation(s) in RCA: 134] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Lindqvist Y, Koskiniemi H, Jansson A, Sandalova T, Schnell R, Liu Z, Mäntsälä P, Niemi J, Schneider G. Structural basis for substrate recognition and specificity in aklavinone-11-hydroxylase from rhodomycin biosynthesis. J Mol Biol 2009; 393:966-77. [PMID: 19744497 DOI: 10.1016/j.jmb.2009.09.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Revised: 08/28/2009] [Accepted: 09/02/2009] [Indexed: 11/19/2022]
Abstract
In the biosynthesis of several anthracyclines, aromatic polyketides produced by many Streptomyces species, the aglycone core is modified by a specific flavin adenine dinucleotide (FAD)- and NAD(P)H-dependent aklavinone-11-hydroxylase. Here, we report the crystal structure of a ternary complex of this enzyme from Streptomyces purpurascens, RdmE, with FAD and the substrate aklavinone. The enzyme is built up of three domains, a FAD-binding domain, a domain involved in substrate binding, and a C-terminal thioredoxin-like domain of unknown function. RdmE exhibits structural similarity to aromatic hydroxylases from the p-hydroxybenzoate hydroxylase family, but unlike most other related enzymes, RdmE is a monomer. The substrate is bound in a hydrophobic pocket in the interior of the enzyme, and access to this pocket is provided through a different route than for the isoalloxazine ring of FAD-the backside of the ligand binding cleft. The architecture of the substrate binding pocket and the observed enzyme-aklavinone interactions provide a structural explanation for the specificity of the enzyme for non-glycosylated substrates with C9-R stereochemistry. The isoalloxazine ring of the flavin cofactor is bound in the "out" conformation but can be modeled in the "in" conformation without invoking large conformational changes of the enzyme. This model places the flavin ring in a position suitable for catalysis, almost perpendicular to the tetracyclic ring system of the substrate and with a distance of the C4a carbon atom of the isoalloxazine ring to the C-11 carbon atom of the substrate of 4.8 A. The structure suggested that a Tyr224-Arg373 pair might be involved in proton abstraction at the C-6 hydroxyl group, thereby increasing the nucleophilicity of the aromatic ring system and facilitating electrophilic attack by the perhydroxy-flavin intermediate. Replacement of Tyr224 by phenylalanine results in inactive enzyme, whereas mutants at position Arg373 retain catalytic activity close to wild-type level. These data establish an essential role of residue Tyr224 in catalysis, possibly in aligning the substrate in a position suitable for catalysis.
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Affiliation(s)
- Ylva Lindqvist
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm S-171 77, Sweden
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Ranieri DI, Hofstetter H, Hofstetter O. Computational structural analysis of an anti-L-amino acid antibody and inversion of its stereoselectivity. J Sep Sci 2009; 32:1686-95. [PMID: 19472280 DOI: 10.1002/jssc.200800694] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The binding site of a monoclonal anti-L-amino acid antibody (anti-L-AA) was modeled using the program SWISS-MODEL. Docking experiments with the enantiomers of phenylalanine revealed that the antibody interacts with L-phenylalanine via hydrogen bonds and hydrophobic contacts, whereas the D-enantiomer is rejected due to steric hindrance. Comparison of the sequences of this antibody and an anti-D-amino acid antibody (anti-D-AA) indicates that both immunoglobulins derived from the same germline progenitor. Substitution of four amino acids residues, three in the framework and one in the complementarity determining regions (CDRs), allowed in silico conversion of the anti-L-AA into an antibody that stereoselectively binds D-phenylalanine.
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Affiliation(s)
- Daniel I Ranieri
- Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb 60115-2862, USA
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Silvennoinen L, Sandalova T, Schneider G. The polyketide cyclase RemF from Streptomyces resistomycificus
contains an unusual octahedral zinc binding site. FEBS Lett 2009; 583:2917-21. [DOI: 10.1016/j.febslet.2009.07.061] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Revised: 07/30/2009] [Accepted: 07/30/2009] [Indexed: 11/28/2022]
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