1
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Bonhomme S, Contreras-Martel C, Dessen A, Macheboeuf P. Architecture of a PKS-NRPS hybrid megaenzyme involved in the biosynthesis of the genotoxin colibactin. Structure 2023:S0969-2126(23)00095-3. [PMID: 37059096 DOI: 10.1016/j.str.2023.03.012] [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: 07/06/2022] [Revised: 10/21/2022] [Accepted: 03/20/2023] [Indexed: 04/16/2023]
Abstract
The genotoxin colibactin produced by Escherichia coli is involved in the development of colorectal cancers. This secondary metabolite is synthesized by a multi-protein machinery, mainly composed of non-ribosomal peptide synthetase (NRPS)/polyketide synthase (PKS) enzymes. In order to decipher the function of a PKS-NRPS hybrid enzyme implicated in a key step of colibactin biosynthesis, we conducted an extensive structural characterization of the ClbK megaenzyme. Here we present the crystal structure of the complete trans-AT PKS module of ClbK showing structural specificities of hybrid enzymes. In addition, we report the SAXS solution structure of the full-length ClbK hybrid that reveals a dimeric organization as well as several catalytic chambers. These results provide a structural framework for the transfer of a colibactin precursor through a PKS-NRPS hybrid enzyme and can pave the way for re-engineering PKS-NRPS hybrid megaenzymes to generate diverse metabolites with many applications.
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Affiliation(s)
- Sarah Bonhomme
- University Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale (IBS), Bacterial Pathogenesis Group, 38000 Grenoble, France
| | - Carlos Contreras-Martel
- University Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale (IBS), Bacterial Pathogenesis Group, 38000 Grenoble, France
| | - Andréa Dessen
- University Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale (IBS), Bacterial Pathogenesis Group, 38000 Grenoble, France
| | - Pauline Macheboeuf
- University Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale (IBS), Bacterial Pathogenesis Group, 38000 Grenoble, France.
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2
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Fortinez CM, Bloudoff K, Harrigan C, Sharon I, Strauss M, Schmeing TM. Structures and function of a tailoring oxidase in complex with a nonribosomal peptide synthetase module. Nat Commun 2022; 13:548. [PMID: 35087027 PMCID: PMC8795117 DOI: 10.1038/s41467-022-28221-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 12/19/2021] [Indexed: 12/15/2022] Open
Abstract
Nonribosomal peptide synthetases (NRPSs) are large modular enzymes that synthesize secondary metabolites and natural product therapeutics. Most NRPS biosynthetic pathways include an NRPS and additional proteins that introduce chemical modifications before, during or after assembly-line synthesis. The bacillamide biosynthetic pathway is a common, three-protein system, with a decarboxylase that prepares an NRPS substrate, an NRPS, and an oxidase. Here, the pathway is reconstituted in vitro. The oxidase is shown to perform dehydrogenation of the thiazoline in the peptide intermediate while it is covalently attached to the NRPS, as the penultimate step in bacillamide D synthesis. Structural analysis of the oxidase reveals a dimeric, two-lobed architecture with a remnant RiPP recognition element and a dramatic wrapping loop. The oxidase forms a stable complex with the NRPS and dimerizes it. We visualized co-complexes of the oxidase bound to the elongation module of the NRPS using X-ray crystallography and cryo-EM. The three active sites (for adenylation, condensation/cyclization, and oxidation) form an elegant arc to facilitate substrate delivery. The structures enabled a proof-of-principle bioengineering experiment in which the BmdC oxidase domain is embedded into the NRPS.
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Affiliation(s)
- Camille Marie Fortinez
- Department of Biochemistry, McGill University, Montréal, QC, H3G 0B1, Canada.,Centre de recherche en biologie structurale, McGill University, Montréal, QC, H3G 0B1, Canada
| | - Kristjan Bloudoff
- Department of Biochemistry, McGill University, Montréal, QC, H3G 0B1, Canada.,Centre de recherche en biologie structurale, McGill University, Montréal, QC, H3G 0B1, Canada
| | - Connor Harrigan
- Department of Biochemistry, McGill University, Montréal, QC, H3G 0B1, Canada.,Centre de recherche en biologie structurale, McGill University, Montréal, QC, H3G 0B1, Canada
| | - Itai Sharon
- Department of Biochemistry, McGill University, Montréal, QC, H3G 0B1, Canada.,Centre de recherche en biologie structurale, McGill University, Montréal, QC, H3G 0B1, Canada
| | - Mike Strauss
- Centre de recherche en biologie structurale, McGill University, Montréal, QC, H3G 0B1, Canada.,Department of Anatomy and Cell Biology, McGill University, Montréal, QC, H3A 0C7, Canada
| | - T Martin Schmeing
- Department of Biochemistry, McGill University, Montréal, QC, H3G 0B1, Canada. .,Centre de recherche en biologie structurale, McGill University, Montréal, QC, H3G 0B1, Canada.
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3
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Reprogramming of the antimycin NRPS-PKS assembly lines inspired by gene evolution. Nat Commun 2018; 9:3534. [PMID: 30166552 PMCID: PMC6117356 DOI: 10.1038/s41467-018-05877-z] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 08/01/2018] [Indexed: 11/09/2022] Open
Abstract
Reprogramming of the NRPS/PKS assembly line is an attractive method for the production of new bioactive molecules. However, it is usually hampered by the loss of intimate domain/module interactions required for the precise control of chain transfer and elongation reactions. In this study, we first establish heterologous expression systems of the unique antimycin-type cyclic depsipeptides: JBIR-06 (tri-lactone) and neoantimycin (tetra-lactone), and engineer their biosyntheses by taking advantage of bioinformatic analyses and evolutionary insights. As a result, we successfully accomplish three manipulations: (i) ring contraction of neoantimycin (from tetra-lactone to tri-lactone), (ii) ring expansion of JBIR-06 (from tri-lactone to tetra-lactone), and (iii) alkyl chain diversification of JBIR-06 by the incorporation of various alkylmalonyl-CoA extender units, to generate a set of unnatural derivatives in practical yields. This study presents a useful strategy for engineering NRPS-PKS module enzymes, based on nature’s diversification of the domain and module organizations. Modifying the non-ribosomal peptide synthase (NRPS)/polyketide synthase (PKS) pathway to generate novel non-ribosomal peptides often results in a loss of productivity. Here the authors use evolutionary alignments of NRPS/PKS gene clusters to guide rational design of complexes that can produce novel lactones.
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4
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Chang CY, Lohman JR, Huang T, Michalska K, Bigelow L, Rudolf JD, Jedrzejczak R, Yan X, Ma M, Babnigg G, Joachimiak A, Phillips GN, Shen B. Structural Insights into the Free-Standing Condensation Enzyme SgcC5 Catalyzing Ester-Bond Formation in the Biosynthesis of the Enediyne Antitumor Antibiotic C-1027. Biochemistry 2018. [PMID: 29533601 DOI: 10.1021/acs.biochem.8b00174] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
C-1027 is a chromoprotein enediyne antitumor antibiotic, consisting of the CagA apoprotein and the C-1027 chromophore. The C-1027 chromophore features a nine-membered enediyne core appended with three peripheral moieties, including an ( S)-3-chloro-5-hydroxy-β-tyrosine. In a convergent biosynthesis of the C-1027 chromophore, the ( S)-3-chloro-5-hydroxy-β-tyrosine moiety is appended to the enediyne core by the free-standing condensation enzyme SgcC5. Unlike canonical condensation domains from the modular nonribosomal peptide synthetases that catalyze amide-bond formation, SgcC5 catalyzes ester-bond formation, as demonstrated in vitro, between SgcC2-tethered ( S)-3-chloro-5-hydroxy-β-tyrosine and ( R)-1-phenyl-1,2-ethanediol, a mimic of the enediyne core as an acceptor substrate. Here, we report that (i) genes encoding SgcC5 homologues are widespread among both experimentally confirmed and bioinformatically predicted enediyne biosynthetic gene clusters, forming a new clade of condensation enzymes, (ii) SgcC5 shares a similar overall structure with the canonical condensation domains but forms a homodimer in solution, the active site of which is located in a cavity rather than a tunnel typically seen in condensation domains, and (iii) the catalytic histidine of SgcC5 activates the 2-hydroxyl group, while a hydrogen-bond network in SgcC5 prefers the R-enantiomer of the acceptor substrate, accounting for the regio- and stereospecific ester-bond formation between SgcC2-tethered ( S)-3-chloro-5-hydroxy-β-tyrosine and ( R)-1-phenyl-1,2-ethanediol upon acid-base catalysis. These findings expand the catalytic repertoire and reveal new insights into the structure and mechanism of condensation enzymes.
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Affiliation(s)
- Chin-Yuan Chang
- Department of Chemistry , The Scripps Research Institute , Jupiter , Florida 33458 , United States
| | - Jeremy R Lohman
- Department of Chemistry , The Scripps Research Institute , Jupiter , Florida 33458 , United States
| | - Tingting Huang
- Department of Chemistry , The Scripps Research Institute , Jupiter , Florida 33458 , United States
| | - Karolina Michalska
- Midwest Center for Structural Genomics, Biosciences Division , Argonne National Laboratory , Argonne , Illinois 60439 , United States
| | - Lance Bigelow
- Midwest Center for Structural Genomics, Biosciences Division , Argonne National Laboratory , Argonne , Illinois 60439 , United States
| | - Jeffrey D Rudolf
- Department of Chemistry , The Scripps Research Institute , Jupiter , Florida 33458 , United States
| | - Robert Jedrzejczak
- Midwest Center for Structural Genomics, Biosciences Division , Argonne National Laboratory , Argonne , Illinois 60439 , United States
| | - Xiaohui Yan
- Department of Chemistry , The Scripps Research Institute , Jupiter , Florida 33458 , United States
| | - Ming Ma
- Department of Chemistry , The Scripps Research Institute , Jupiter , Florida 33458 , United States
| | - Gyorgy Babnigg
- Midwest Center for Structural Genomics, Biosciences Division , Argonne National Laboratory , Argonne , Illinois 60439 , United States.,Center for Structural Genomics of Infectious Diseases , University of Chicago , Chicago , Illinois 60637 , United States
| | - Andrzej Joachimiak
- Midwest Center for Structural Genomics, Biosciences Division , Argonne National Laboratory , Argonne , Illinois 60439 , United States.,Center for Structural Genomics of Infectious Diseases , University of Chicago , Chicago , Illinois 60637 , United States.,Structural Biology Center, Biosciences Division , Argonne National Laboratory , Argonne , Illinois 60439 , United States
| | - George N Phillips
- BioSciences at Rice and Department of Chemistry , Rice University , Houston , Texas 77251 , United States
| | - Ben Shen
- Department of Chemistry , The Scripps Research Institute , Jupiter , Florida 33458 , United States.,Department of Molecular Medicine , The Scripps Research Institute , Jupiter , Florida 33458 , United States.,Natural Products Library Initiative at The Scripps Research Institute , The Scripps Research Institute , Jupiter , Florida 33458 , United States
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5
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Kabir K, Deeni YY, Hapca SM, Moore L, Spiers AJ. Uncovering behavioural diversity amongst high-strength Pseudomonas spp. surfactants at the limit of liquid surface tension reduction. FEMS Microbiol Lett 2018; 365:4810749. [DOI: 10.1093/femsle/fny008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 01/15/2018] [Indexed: 11/15/2022] Open
Affiliation(s)
- Kamaluddeen Kabir
- School of Science, Engineering and Technology, Abertay University, Bell Street, Dundee, DD1 1HG, UK
| | - Yusuf Y Deeni
- School of Science, Engineering and Technology, Abertay University, Bell Street, Dundee, DD1 1HG, UK
| | - Simona M Hapca
- School of Science, Engineering and Technology, Abertay University, Bell Street, Dundee, DD1 1HG, UK
| | - Luke Moore
- School of Science, Engineering and Technology, Abertay University, Bell Street, Dundee, DD1 1HG, UK
| | - Andrew J Spiers
- School of Science, Engineering and Technology, Abertay University, Bell Street, Dundee, DD1 1HG, UK
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6
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Miyanaga A, Kudo F, Eguchi T. Protein–protein interactions in polyketide synthase–nonribosomal peptide synthetase hybrid assembly lines. Nat Prod Rep 2018; 35:1185-1209. [DOI: 10.1039/c8np00022k] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The protein–protein interactions in polyketide synthase–nonribosomal peptide synthetase hybrids are summarized and discussed.
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Affiliation(s)
- Akimasa Miyanaga
- Department of Chemistry
- Tokyo Institute of Technology
- Tokyo 152-8551
- Japan
| | - Fumitaka Kudo
- Department of Chemistry
- Tokyo Institute of Technology
- Tokyo 152-8551
- Japan
| | - Tadashi Eguchi
- Department of Chemistry
- Tokyo Institute of Technology
- Tokyo 152-8551
- Japan
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7
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Mapping of the Communication-Mediating Interface in Nonribosomal Peptide Synthetases Using a Genetically Encoded Photocrosslinker Supports an Upside-Down Helix-Hand Motif. J Mol Biol 2016; 428:4345-4360. [DOI: 10.1016/j.jmb.2016.09.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 09/07/2016] [Accepted: 09/09/2016] [Indexed: 12/28/2022]
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8
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Kokona B, Winesett ES, Nikolai von Krusenstiern A, Cryle MJ, Fairman R, Charkoudian LK. Probing the selectivity of β-hydroxylation reactions in non-ribosomal peptide synthesis using analytical ultracentrifugation. Anal Biochem 2016; 495:42-51. [DOI: 10.1016/j.ab.2015.11.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 11/06/2015] [Accepted: 11/09/2015] [Indexed: 12/17/2022]
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9
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The structural biology of biosynthetic megaenzymes. Nat Chem Biol 2015; 11:660-70. [PMID: 26284673 DOI: 10.1038/nchembio.1883] [Citation(s) in RCA: 142] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 07/02/2015] [Indexed: 01/27/2023]
Abstract
The modular polyketide synthases (PKSs) and nonribosomal peptide synthetases (NRPSs) are among the largest and most complicated enzymes in nature. In these biosynthetic systems, independently folding protein domains, which are organized into units called 'modules', operate in assembly-line fashion to construct polymeric chains and tailor their functionalities. Products of PKSs and NRPSs include a number of blockbuster medicines, and this has motivated researchers to understand how they operate so that they can be modified by genetic engineering. Beginning in the 1990s, structural biology has provided a number of key insights. The emerging picture is one of remarkable dynamics and conformational programming in which the chemical states of individual catalytic domains are communicated to the others, configuring the modules for the next stage in the biosynthesis. This unexpected level of complexity most likely accounts for the low success rate of empirical genetic engineering experiments and suggests ways forward for productive megaenzyme synthetic biology.
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10
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Milano T, Paiardini A, Grgurina I, Pascarella S. Type I pyridoxal 5'-phosphate dependent enzymatic domains embedded within multimodular nonribosomal peptide synthetase and polyketide synthase assembly lines. BMC STRUCTURAL BIOLOGY 2013. [PMID: 24148833 DOI: 10.1186/1472‐6807‐13‐26] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND Pyridoxal 5'-phosphate (PLP)-dependent enzymes of fold type I, the most studied structural class of the PLP-dependent enzyme superfamily, are known to exist as stand-alone homodimers or homotetramers. These enzymes have been found also embedded in multimodular and multidomain assembly lines involved in the biosynthesis of polyketides (PKS) and nonribosomal peptides (NRPS). The aim of this work is to provide a proteome-wide view of the distribution and characteristics of type I domains covalently integrated in these assemblies in prokaryotes. RESULTS An ad-hoc Hidden Markov profile was calculated using a sequence alignment derived from a multiple structural superposition of distantly related PLP-enzymes of fold type I. The profile was utilized to scan the sequence databank and to collect the proteins containing at least one type I domain linked to a component of an assembly line in bacterial genomes. The domains adjacent to a carrier protein were further investigated. Phylogenetic analysis suggested the presence of four PLP-dependent families: Aminotran_3, Beta_elim_lyase and Pyridoxal_deC, occurring mainly within mixed NRPS/PKS clusters, and Aminotran_1_2 found mainly in PKS clusters. Sequence similarity to the reference PLP enzymes with solved structures ranged from 24 to 42% identity. Homology models were built for each representative type I domain and molecular docking simulations with putative substrates were carried out. Prediction of the protein-protein interaction sites evidenced that the surface regions of the type I domains embedded within multienzyme assemblies were different from those of the self-standing enzymes; these structural features appear to be required for productive interactions with the adjacent domains in a multidomain context. CONCLUSIONS This work provides a systematic view of the occurrence of type I domain within NRPS and PKS assembly lines and it predicts their structural characteristics using computational methods. Comparison with the corresponding stand-alone enzymes highlighted the common and different traits related to various aspects of their structure-function relationship. Therefore, the results of this work, on one hand contribute to the understanding of the functional and structural diversity of the PLP-dependent type I enzymes and, on the other, pave the way to further studies aimed at their applications in combinatorial biosynthesis.
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Affiliation(s)
| | | | | | - Stefano Pascarella
- Dipartimento di Scienze Biochimiche "A, Rossi Fanelli", Sapienza - Università di Roma, Roma 00185, Italy.
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11
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Milano T, Paiardini A, Grgurina I, Pascarella S. Type I pyridoxal 5'-phosphate dependent enzymatic domains embedded within multimodular nonribosomal peptide synthetase and polyketide synthase assembly lines. BMC STRUCTURAL BIOLOGY 2013; 13:26. [PMID: 24148833 PMCID: PMC3870968 DOI: 10.1186/1472-6807-13-26] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 10/14/2013] [Indexed: 12/12/2022]
Abstract
BACKGROUND Pyridoxal 5'-phosphate (PLP)-dependent enzymes of fold type I, the most studied structural class of the PLP-dependent enzyme superfamily, are known to exist as stand-alone homodimers or homotetramers. These enzymes have been found also embedded in multimodular and multidomain assembly lines involved in the biosynthesis of polyketides (PKS) and nonribosomal peptides (NRPS). The aim of this work is to provide a proteome-wide view of the distribution and characteristics of type I domains covalently integrated in these assemblies in prokaryotes. RESULTS An ad-hoc Hidden Markov profile was calculated using a sequence alignment derived from a multiple structural superposition of distantly related PLP-enzymes of fold type I. The profile was utilized to scan the sequence databank and to collect the proteins containing at least one type I domain linked to a component of an assembly line in bacterial genomes. The domains adjacent to a carrier protein were further investigated. Phylogenetic analysis suggested the presence of four PLP-dependent families: Aminotran_3, Beta_elim_lyase and Pyridoxal_deC, occurring mainly within mixed NRPS/PKS clusters, and Aminotran_1_2 found mainly in PKS clusters. Sequence similarity to the reference PLP enzymes with solved structures ranged from 24 to 42% identity. Homology models were built for each representative type I domain and molecular docking simulations with putative substrates were carried out. Prediction of the protein-protein interaction sites evidenced that the surface regions of the type I domains embedded within multienzyme assemblies were different from those of the self-standing enzymes; these structural features appear to be required for productive interactions with the adjacent domains in a multidomain context. CONCLUSIONS This work provides a systematic view of the occurrence of type I domain within NRPS and PKS assembly lines and it predicts their structural characteristics using computational methods. Comparison with the corresponding stand-alone enzymes highlighted the common and different traits related to various aspects of their structure-function relationship. Therefore, the results of this work, on one hand contribute to the understanding of the functional and structural diversity of the PLP-dependent type I enzymes and, on the other, pave the way to further studies aimed at their applications in combinatorial biosynthesis.
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Affiliation(s)
| | | | | | - Stefano Pascarella
- Dipartimento di Scienze Biochimiche "A, Rossi Fanelli", Sapienza - Università di Roma, Roma 00185, Italy.
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12
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Zheng J, Fage CD, Demeler B, Hoffman DW, Keatinge-Clay AT. The missing linker: a dimerization motif located within polyketide synthase modules. ACS Chem Biol 2013; 8:1263-70. [PMID: 23489133 PMCID: PMC4365927 DOI: 10.1021/cb400047s] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The dimerization of multimodular polyketide synthases is essential for their function. Motifs that supplement the contacts made by dimeric polyketide synthase enzymes have previously been characterized outside the boundaries of modules, at the N- and C-terminal ends of polyketide synthase subunits. Here we describe a heretofore uncharacterized dimerization motif located within modules. The dimeric state of this dimerization element was elucidated through the 2.6 Å resolution crystal structure of a fragment containing a dimerization element and a ketoreductase. The solution structure of a standalone dimerization element was revealed by nuclear magnetic resonance spectroscopy to be consistent with that of the crystal structure, and its dimerization constant was measured through analytical ultracentrifugation to be ∼20 μM. The dimer buries ∼990 Å(2) at its interface, and its C-terminal helices rigidly connect to ketoreductase domains to constrain their locations within a module. These structural restraints permitted the construction of a common type of polyketide synthase module.
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Affiliation(s)
- Jianting Zheng
- Department of Chemistry & Biochemistry, The University of Texas at Austin, 1 University Station A5300, Austin, TX 78712
| | - Christopher D. Fage
- Department of Chemistry & Biochemistry, The University of Texas at Austin, 1 University Station A5300, Austin, TX 78712
| | - Borries Demeler
- Department of Biochemistry, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229
| | - David W. Hoffman
- Department of Chemistry & Biochemistry, The University of Texas at Austin, 1 University Station A5300, Austin, TX 78712
| | - Adrian T. Keatinge-Clay
- Department of Chemistry & Biochemistry, The University of Texas at Austin, 1 University Station A5300, Austin, TX 78712
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13
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Meneely KM, Lamb AL. Two structures of a thiazolinyl imine reductase from Yersinia enterocolitica provide insight into catalysis and binding to the nonribosomal peptide synthetase module of HMWP1. Biochemistry 2012; 51:9002-13. [PMID: 23066849 DOI: 10.1021/bi3011016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The thiazolinyl imine reductase from Yersinia enterocolitica (Irp3) catalyzes the NADPH-dependent reduction of a thiazoline ring in an intermediate for the formation of the siderophore yersiniabactin. Two structures of Irp3 were determined in the apo (1.85 Å) and NADP(+)-bound (2.31 Å) forms. Irp3 is structurally homologous to sugar oxidoreductases such as glucose-fructose oxidoreductase and 1,5-anhydro-d-fructose reductase, as well as to biliverdin reductase. A homology model of the thiazolinyl imine reductase from Pseudomonas aeruginosa (PchG) was generated. Extensive loop insertions are observed in the C-terminal domain that are unique to Irp3 and PchG and not found in the structural homologues that recognize small molecular substrates. These loops are hypothesized to be important for binding of the nonribosomal peptide synthetase modules (found in HMWP1 and PchF, respectively) to which the substrate of the reductase is covalently attached. A catalytic mechanism for the donation of a proton from a general acid (either histidine 101 or tyrosine 128) and the donation of a hydride from C4 of nicotinamide of the NADPH cofactor is proposed for reduction of the carbon-nitrogen double bond of the thiazoline.
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Affiliation(s)
- Kathleen M Meneely
- Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas 66045, United States
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14
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Crosby J, Crump MP. The structural role of the carrier protein--active controller or passive carrier. Nat Prod Rep 2012; 29:1111-37. [PMID: 22930263 DOI: 10.1039/c2np20062g] [Citation(s) in RCA: 132] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Common to all FASs, PKSs and NRPSs is a remarkable component, the acyl or peptidyl carrier protein (A/PCP). These take the form of small individual proteins in type II systems or discrete folded domains in the multi-domain type I systems and are characterized by a fold consisting of three major α-helices and between 60-100 amino acids. This protein is central to these biosynthetic systems and it must bind and transport a wide variety of functionalized ligands as well as mediate numerous protein-protein interactions, all of which contribute to efficient enzyme turnover. This review covers the structural and biochemical characterization of carrier proteins, as well as assessing their interactions with different ligands, and other synthase components. Finally, their role as an emerging tool in biotechnology is discussed.
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Affiliation(s)
- John Crosby
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
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15
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Van Den Berg M, Gidijala L, Kiela J, Bovenberg R, Vander Keli I. Biosynthesis of active pharmaceuticals: β-lactam biosynthesis in filamentous fungi. Biotechnol Genet Eng Rev 2011; 27:1-32. [PMID: 21415891 DOI: 10.1080/02648725.2010.10648143] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
β-lactam antibiotics (e.g. penicillins, cephalosporins) are of major clinical importance and contribute to over 40% of the total antibiotic market. These compounds are produced as secondary metabolites by certain actinomycetes and filamentous fungi (e.g. Penicillium, Aspergillus and Acremonium species). The industrial producer of penicillin is the fungus Penicillium chrysogenum. The enzymes of the penicillin biosynthetic pathway are well characterized and most of them are encoded by genes that are organized in a cluster in the genome. Remarkably, the penicillin biosynthetic pathway is compartmentalized: the initial steps of penicillin biosynthesis are catalyzed by cytosolic enzymes, whereas the two final steps involve peroxisomal enzymes. Here, we describe the biochemical properties of the enzymes of β-lactam biosynthesis in P. chrysogenum and the role of peroxisomes in this process. An overview is given on strain improvement programs via classical mutagenesis and, more recently, genetic engineering, leading to more productive strains. Also, the potential of using heterologous hosts for the development of novel ß-lactam antibiotics and non-ribosomal peptide synthetase-based peptides is discussed.
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Affiliation(s)
- Marco Van Den Berg
- Molecular Cell Biology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), Kluyver Center for Genomics of Industrial Fermentation, University of Groningen, The Netherlands.
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16
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Molecular recognition between ketosynthase and acyl carrier protein domains of the 6-deoxyerythronolide B synthase. Proc Natl Acad Sci U S A 2010; 107:22066-71. [PMID: 21127271 DOI: 10.1073/pnas.1014081107] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Every polyketide synthase module has an acyl carrier protein (ACP) and a ketosynthase (KS) domain that collaborate to catalyze chain elongation. The same ACP then engages the KS domain of the next module to facilitate chain transfer. Understanding the mechanism for this orderly progress of the growing polyketide chain represents a fundamental challenge in assembly line enzymology. Using both experimental and computational approaches, the molecular basis for KS-ACP interactions in the 6-deoxyerythronolide B synthase has been decoded. Surprisingly, KS-ACP recognition is controlled at different interfaces during chain elongation versus chain transfer. In fact, chain elongation is controlled at a docking site remote from the catalytic center. Not only do our findings reveal a new principle in the modular control of polyketide antibiotic biosynthesis, they also provide a rationale for the mandatory homodimeric structure of polyketide synthases, in contrast to the monomeric nonribosomal peptide synthetases.
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Hur GH, Meier JL, Baskin J, Codelli JA, Bertozzi CR, Marahiel MA, Burkart MD. Crosslinking studies of protein-protein interactions in nonribosomal peptide biosynthesis. CHEMISTRY & BIOLOGY 2009; 16:372-81. [PMID: 19345117 PMCID: PMC2743379 DOI: 10.1016/j.chembiol.2009.02.009] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2008] [Revised: 02/09/2009] [Accepted: 02/11/2009] [Indexed: 11/25/2022]
Abstract
Selective protein-protein interactions between nonribosomal peptide synthetase (NRPS) proteins, governed by communication-mediating (COM) domains, are responsible for proper translocation of biosynthetic intermediates to produce the natural product. In this study, we developed a crosslinking assay, utilizing bioorthogonal probes compatible with carrier protein modification, for probing the protein interactions between COM domains of NRPS enzymes. Employing the Huisgen 1,3-dipolar cycloaddition of azides and alkynes, we examined crosslinking of cognate NRPS modules within the tyrocidine pathway and demonstrated the sensitivity of our panel of crosslinking probes toward the selective protein interactions of compatible COM domains. These studies indicate that copper-free crosslinking substrates uniquely offer a diagnostic probe for protein-protein interactions. Likewise, these crosslinking probes serve as ideal chemical tools for structural studies between NRPS modules where functional assays are lacking.
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Affiliation(s)
- Gene H. Hur
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093
| | - Jordan L. Meier
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093
| | - Jeremy Baskin
- Department of Chemistry, University of California, Berkeley, B-84 Hildebrand Hall, Berkeley, California 94720
| | - Julian A. Codelli
- Department of Chemistry, University of California, Berkeley, B-84 Hildebrand Hall, Berkeley, California 94720
| | - Carolyn R. Bertozzi
- Department of Chemistry, University of California, Berkeley, B-84 Hildebrand Hall, Berkeley, California 94720
| | - Mohamed A. Marahiel
- Fachbereich Chemie/Biochemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, 35043 Marburg, Germany
| | - Michael D. Burkart
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093
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Meier JL, Burkart MD. The chemical biology of modular biosynthetic enzymes. Chem Soc Rev 2009; 38:2012-45. [DOI: 10.1039/b805115c] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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19
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Tanovic A, Samel SA, Essen LO, Marahiel MA. Crystal structure of the termination module of a nonribosomal peptide synthetase. Science 2008; 321:659-63. [PMID: 18583577 DOI: 10.1126/science.1159850] [Citation(s) in RCA: 261] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Nonribosomal peptide synthetases (NRPSs) are modular multidomain enzymes that act as an assembly line to catalyze the biosynthesis of complex natural products. The crystal structure of the 144-kilodalton Bacillus subtilis termination module SrfA-C was solved at 2.6 angstrom resolution. The adenylation and condensation domains of SrfA-C associate closely to form a catalytic platform, with their active sites on the same side of the platform. The peptidyl carrier protein domain is flexibly tethered to this platform and thus can move with its substrate-loaded 4'-phosphopantetheine arm between the active site of the adenylation domain and the donor side of the condensation domain. The SrfA-C crystal structure has implications for the rational redesign of NRPSs as a means of producing novel bioactive peptides.
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Affiliation(s)
- Alan Tanovic
- Biochemistry, Department of Chemistry, Philipps University Marburg, Hans-Meerwein-Strasse, D35032 Marburg, Germany
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Hoyer KM, Mahlert C, Marahiel MA. The iterative gramicidin s thioesterase catalyzes peptide ligation and cyclization. ACTA ACUST UNITED AC 2008; 14:13-22. [PMID: 17254948 PMCID: PMC7129787 DOI: 10.1016/j.chembiol.2006.10.011] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2006] [Revised: 09/19/2006] [Accepted: 10/30/2006] [Indexed: 11/30/2022]
Abstract
Here, we present a comprehensive in vitro characterization of the excised iterative, bimodular PCP-TE of the gramicidin S synthetase GrsB, which is able to act both as a ligation and a cyclization catalyst. Using the native pentapeptidyl-thioester substrates, GrsB PCP-TE catalyzes the dimerization and subsequent formation of the decapeptide lactam gramicidin S. Interestingly, the detection of linear decapeptidyl-SNAC as an enzyme-dependent intermediate supports the iterative mechanism in vivo, in which two pentapeptides, one bound as an ester to the active site serine of the TE domain and the second bound as a thioester to the adjacent pan-PCP, are ligated to a decapeptidyl-pan-PCP that subsequently transferred to the adjacent TE domain and cyclized. Moreover, GrsB PCP-TE can handle different substrates length, leading not only to dimerization, but also to trimerization and the formation of different ring sizes.
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Affiliation(s)
- Katharina M. Hoyer
- Fachbereich Chemie/Biochemie, Philipps-Universität Marburg, Hans-Meerwein Strasse, 35032 Marburg, Germany
| | - Christoph Mahlert
- Fachbereich Chemie/Biochemie, Philipps-Universität Marburg, Hans-Meerwein Strasse, 35032 Marburg, Germany
| | - Mohamed A. Marahiel
- Fachbereich Chemie/Biochemie, Philipps-Universität Marburg, Hans-Meerwein Strasse, 35032 Marburg, Germany
- Corresponding author
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21
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Weissman KJ, Müller R. Protein–Protein Interactions in Multienzyme Megasynthetases. Chembiochem 2008; 9:826-48. [DOI: 10.1002/cbic.200700751] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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22
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Richter CD, Nietlispach D, Broadhurst RW, Weissman KJ. Multienzyme docking in hybrid megasynthetases. Nat Chem Biol 2007; 4:75-81. [DOI: 10.1038/nchembio.2007.61] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2007] [Accepted: 10/30/2007] [Indexed: 11/09/2022]
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23
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Fullone MR, Paiardini A, Gross DC, Lu SE, Fiore A, Grgurina I. Mutational analysis and homology modelling of SyrC, the aminoacyltransferase in the biosynthesis of syringomycin. Biochem Biophys Res Commun 2007; 364:201-7. [DOI: 10.1016/j.bbrc.2007.09.116] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2007] [Accepted: 09/23/2007] [Indexed: 11/27/2022]
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24
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Wenzel SC, Müller R. Myxobacterial natural product assembly lines: fascinating examples of curious biochemistry. Nat Prod Rep 2007; 24:1211-24. [DOI: 10.1039/b706416k] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Chiocchini C, Linne U, Stachelhaus T. In Vivo Biocombinatorial Synthesis of Lipopeptides by COM Domain-Mediated Reprogramming of the Surfactin Biosynthetic Complex. ACTA ACUST UNITED AC 2006; 13:899-908. [PMID: 16931339 DOI: 10.1016/j.chembiol.2006.06.015] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2006] [Revised: 05/30/2006] [Accepted: 06/26/2006] [Indexed: 10/24/2022]
Abstract
The intermolecular communication within NRPS complexes relies on the coordinated interplay of donor and acceptor communication-mediating (COM) domains. In this study, the potential of COM domains was exploited in vivo by establishing a system for the true biocombinatorial synthesis of lipopeptides via directed reprogramming of a natural NRP biosynthetic assembly line (i.e., surfactin). By means of COM domain swapping, these experiments verified the decisive role of COM domains for the control of protein-protein interactions between NRPSs, demonstrated the functionality of COM domain pairs even in the context of a heterologous host and NRPS system, and allowed for the intended skipping of a biosynthetic enzyme within a multienzymatic biosynthetic complex. Ultimately, abrogation of the selectivity barrier provided by COM domains afforded the successful simultaneous, biocombinatorial synthesis of distinct lipopeptide products.
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Affiliation(s)
- Claudia Chiocchini
- Philipps-University Marburg, Faculty of Chemistry/Biochemistry, Hans-Meerwein-Strasse, D-35032 Marburg, Germany
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Hicks LM, Balibar CJ, Walsh CT, Kelleher NL, Hillson NJ. Probing intra- versus interchain kinetic preferences of L-Thr acylation on dimeric VibF with mass spectrometry. Biophys J 2006; 91:2609-19. [PMID: 16815901 PMCID: PMC1562378 DOI: 10.1529/biophysj.106.084848] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We present a method to probe intra- and interchain activities within dimeric nonribosomal peptide synthetases. Utilizing domain inactivation and analytical mass mutants in conjunction with rapid-quench, mass spectrometry, and a probabilistic kinetic model, we have elucidated the pre-steady-state intra- and interchain rates and the corresponding flux of the acylation of L-Thr onto VibF. Although the intra rate is significantly faster than the inter rate, the data are most consistent with an even flux of covalent substrate loading where neither pathway dominates. These pre-steady-state results confirm previous steady-state in vitro mutant complementation studies of VibF. Extension of this methodology to other dimeric nonribosomal peptide synthetases, and to the related fatty acid and polyketide synthases, will further our biophysical understanding of their acyl-intermediate-processing pathways.
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Affiliation(s)
- Leslie M Hicks
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
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Sieber SA, Marahiel MA. Molecular mechanisms underlying nonribosomal peptide synthesis: approaches to new antibiotics. Chem Rev 2005; 105:715-38. [PMID: 15700962 DOI: 10.1021/cr0301191] [Citation(s) in RCA: 442] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Stephan A Sieber
- Philipps-Universität Marburg, Fachbereich Chemie/Biochemie, Hans-Meerwein-Strasse, 35032 Marburg, Germany
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28
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Abstract
Bacteria and fungi use large multifunctional enzymes, the so-called nonribosomal peptide synthetases (NRPSs), to produce peptides of broad structural and biological activity. Biochemical studies have contributed substantially to the understanding of the key principles of these modular enzymes that can draw on a much larger number of catalytic tools for the incorporation of unusual features compared with the ribosomal system. Several crystal structures of NRPS-domains have yielded deep insight into the catalytic mechanisms involved and have led to a better prediction of the products assembled and to the construction of hybrid enzymes. In addition to the structure-function relationship of the core- and tailoring-domains of NRPSs, which is the main focus of this review, different biosynthetic strategies and essential enzymes for posttranslational modification and editing are discussed.
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Affiliation(s)
- Robert Finking
- Philipps-Universität Marburg, Fachbereich Chemie/Biochemie, Hans-Meerwein-Strasse, 35043 Marburg, Germany.
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Liu F, Garneau S, Walsh CT. Hybrid Nonribosomal Peptide-Polyketide Interfaces in Epothilone Biosynthesis. ACTA ACUST UNITED AC 2004; 11:1533-42. [PMID: 15556004 DOI: 10.1016/j.chembiol.2004.08.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2004] [Revised: 08/14/2004] [Accepted: 08/23/2004] [Indexed: 11/21/2022]
Abstract
Epothilone (Epo) D, an antitumor agent currently in clinical trials, is a hybrid natural product produced by the combined action of nonribosomal peptide synthetases (NRPS) and polyketide synthases (PKS). In the epothilone biosynthetic pathway, EpoB, a 165 kDa NRPS is inserted into an otherwise entirely PKS assembly line, forming two hybrid NRPS-PKS interfaces. In light of the terminal linker effect previously identified in PKS, the N- and C-terminal sequences of EpoB were examined for their roles in propagating the incipient natural product. Eight amino acid residues at EpoB C terminus, in which six are positively charged, were found to be a key component of the C-terminal linker effect. A minimal sequence of 56 residues at EpoB N terminus was required for elongating the acetyl group from the acyl carrier protein (ACP) of EpoA to form methylthiazolyl-S-EpoB.
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Affiliation(s)
- Fei Liu
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA
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Abstract
Combinatorial biosynthesis involves the genetic manipulation of natural product biosynthetic enzymes to produce potential new drug candidates that would otherwise be difficult to obtain. In either a theoretical or practical sense, the number of combinations possible from different types of natural product pathways ranges widely. Enzymes that have been the most amenable to this technology synthesize the polyketides, nonribosomal peptides, and hybrids of the two. The number of polyketide or peptide natural products theoretically possible is huge, but considerable work remains before these large numbers can be realized. Nevertheless, many analogs have been created by this technology, providing useful structure-activity relationship data and leading to a few compounds that may reach the clinic in the next few years. In this review the focus is on recent advances in our understanding of how different enzymes for natural product biosynthesis can be used successfully in this technology.
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Reiber K, Neuhof T, Ozegowski JH, von Döhrend H, Schwecke T. A nonribosomal peptide synthetase involved in the biosynthesis of ampullosporins inSepedonium ampullosporum. J Pept Sci 2003; 9:701-13. [PMID: 14658790 DOI: 10.1002/psc.529] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Recently, the saprophytic ascomycete Sepedonium ampullosporum strain HKI-0053 was isolated from a basidiomycete on account of its premature induction of pigment formation in Phoma destructiva, a process often related to the neuroleptic activity of the inducing compound. The active substance was identified as the 15-membered peptaibol type peptide Ampullosporin. Although to date more than 300 peptaibols have been discovered, their biosynthetic machinery has not been characterized yet. By improving the culture conditions it was possible to grow S. ampullosporum in a submerged culture and to increase Ampullosporin production by more than three times to 33 mg/l at reduced fermentation times. The appearance of two high molecular weight proteins, HMWP1 (1.5 MDa) and HMWP2 (350 kDa) was closely related to the production of Ampullosporin during the course of fermentation. Both proteins showed a cross-reaction with antibodies against a core fragment of nonribosomal peptide synthetases (NRPSs). Biochemical characterization of the partially purified enzymes exhibited selectivity for the substrate amino acid alpha-aminoisobutyric acid (Aib). substantiating their involvement in Ampullosporin biosynthesis. Our data suggest that Ampullosporin synthetase has been isolated, and provides the basis for the characterization of the entire biosynthetic gene cluster. Furthermore, this knowledge will enable the manipulation of its NRPS template, in order to engineer mutant strains of Sepedonium ampullosporum which could produce more potent analogues of Ampullosporin.
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Affiliation(s)
- Kathrin Reiber
- Hans-Knöll-Institut für Naturstoff-Forschung, Beutenbergstrasse 11a, D-07745 Jena, Germany
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32
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Davis BG. 2 Synthetic methods : Part (iii) Biocatalysis and enzymes in organic synthesis. ACTA ACUST UNITED AC 2003. [DOI: 10.1039/b211999b] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Abstract
NRPSs, PKSs, and hybrid NRPS/PKSs are modular proteins with similar assembly-line organizations. Although PKSs function as dimers, new data demonstrate that functional NRPSs are monomeric. This discovery has significant implications for engineering artificial assemblies for the production of novel biotherapeutics.
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Affiliation(s)
- Stuart Smith
- Children's Hospital Oakland Research Institute, 5700 Martin Luther King Jr. Way, Oakland, CA 94609, USA
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