1
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Sharma H, Mondal S, Urquiza U, Esparza C, Bartlett S, Santa-Pinter L, Hill H, White M, Sharma P, Luckett-Chastain L, Cooper A, Rasel M, Gao P, Battaile KP, Shukla SK, Lovell S, Ihnat MA. Synthesis and biological characterization of an orally bioavailable lactate dehydrogenase-A inhibitor against pancreatic cancer. Eur J Med Chem 2024; 275:116598. [PMID: 38925013 DOI: 10.1016/j.ejmech.2024.116598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 06/09/2024] [Accepted: 06/12/2024] [Indexed: 06/28/2024]
Abstract
Lactate dehydrogenase-A (LDHA) is the major isoform of lactate dehydrogenases (LDH) that is overexpressed and linked to poor survival in pancreatic ductal adenocarcinoma (PDAC). Despite some progress, current LDH inhibitors have poor structural and physicochemical properties or exhibit unfavorable pharmacokinetics that have hampered their development. The present study reports the synthesis and biological evaluation of a novel class of LDHA inhibitors comprising a succinic acid monoamide motif. Compounds 6 and 21 are structurally related analogs that demonstrated potent inhibition of LDHA with IC50s of 46 nM and 72 nM, respectively. We solved cocrystal structures of compound 21-bound to LDHA that showed that the compound binds to a distinct allosteric site between the two subunits of the LDHA tetramer. Inhibition of LDHA correlated with reduced lactate production and reduction of glycolysis in MIA PaCa-2 pancreatic cancer cells. The lead compounds inhibit the proliferation of human pancreatic cancer cell lines and patient-derived 3D organoids and exhibit a synergistic cytotoxic effect with the OXPHOS inhibitor phenformin. Unlike current LDHA inhibitors, 6 and 21 have appropriate pharmacokinetics and ligand efficiency metrics, exhibit up to 73% oral bioavailability, and a cumulative half-life greater than 4 h in mice.
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Affiliation(s)
- Horrick Sharma
- Department of Pharmaceutical Sciences, College of Pharmacy, Southwestern Oklahoma State University, Weatherford, OK, USA.
| | - Somrita Mondal
- Department of Pharmaceutical Sciences, College of Pharmacy, Southwestern Oklahoma State University, Weatherford, OK, USA
| | - Uzziah Urquiza
- Department of Biological & Biomedical Sciences, Southwestern Oklahoma State University, Weatherford, OK, USA
| | - Colter Esparza
- Department of Biological & Biomedical Sciences, Southwestern Oklahoma State University, Weatherford, OK, USA
| | - Seth Bartlett
- Department of Pharmaceutical Sciences, College of Pharmacy, Southwestern Oklahoma State University, Weatherford, OK, USA
| | - Landon Santa-Pinter
- Department of Pharmaceutical Sciences, College of Pharmacy, Southwestern Oklahoma State University, Weatherford, OK, USA
| | - Hanna Hill
- Department of Biological & Biomedical Sciences, Southwestern Oklahoma State University, Weatherford, OK, USA
| | - Madalyn White
- Department of Biological & Biomedical Sciences, Southwestern Oklahoma State University, Weatherford, OK, USA
| | - Pragya Sharma
- Department of Biological & Biomedical Sciences, Southwestern Oklahoma State University, Weatherford, OK, USA
| | - Lerin Luckett-Chastain
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Oklahoma Health Sciences Center, Oklahoma City, USA
| | - Anne Cooper
- Protein Structure and X-ray Crystallography Laboratory, The University of Kansas, Lawrence, KS, USA
| | - Mohammad Rasel
- Protein Structure and X-ray Crystallography Laboratory, The University of Kansas, Lawrence, KS, USA
| | - Philip Gao
- Protein Production Group, The University of Kansas, Lawrence, KS, USA
| | | | - Surendra K Shukla
- Department of Oncology Science, OU College of Medicine, Oklahoma City, USA
| | - Scott Lovell
- Protein Structure and X-ray Crystallography Laboratory, The University of Kansas, Lawrence, KS, USA
| | - Michael A Ihnat
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Oklahoma Health Sciences Center, Oklahoma City, USA
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2
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Ren Y, Vettenranta E, Penttinen L, Blomster Andberg M, Koivula A, Rouvinen J, Hakulinen N. Unveiling the importance of the C-terminus in the sugar acid dehydratase of the IlvD/EDD superfamily. Appl Microbiol Biotechnol 2024; 108:436. [PMID: 39126499 DOI: 10.1007/s00253-024-13270-8] [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: 06/05/2024] [Revised: 07/23/2024] [Accepted: 07/27/2024] [Indexed: 08/12/2024]
Abstract
Microbial non-phosphorylative oxidative pathways present promising potential in the biosynthesis of platform chemicals from the hemicellulosic fraction of lignocellulose. An L-arabinonate dehydratase from Rhizobium leguminosarum bv. trifolii catalyzes the rate-limiting step in the non-phosphorylative oxidative pathways, that is, converts sugar acid to 2-dehydro-3-deoxy sugar acid. We have shown earlier that the enzyme forms a dimer of dimers, in which the C-terminal histidine residue from one monomer participates in the formation of the active site of an adjacent monomer. The histidine appears to be conserved across the sequences of sugar acid dehydratases. To study the role of the C-terminus, five variants (H579A, H579F, H579L, H579Q, and H579W) were produced. All variants showed decreased activity for the tested sugar acid substrates, except the variant H579L on D-fuconate, which showed about 20% increase in activity. The reaction kinetic data showed that the substrate preference was slightly modified in H579L compared to the wild-type enzyme, demonstrating that the alternation of the substrate preference of sugar acid dehydratases is possible. In addition, a crystal structure of H579L was determined at 2.4 Å with a product analog 2-oxobutyrate. This is the first enzyme-ligand complex structure from an IlvD/EDD superfamily enzyme. The binding of 2-oxobutyrate suggests how the substrate would bind into the active site in the orientation, which could lead to the dehydration reaction. KEY POINTS: • Mutation of the last histidine at the C-terminus changed the catalytic activity of L-arabinonate dehydratase from R. leguminosarum bv. trifolii against various C5/C6 sugar acids. • The variant H579L of L-arabinonate dehydratase showed an alteration of substrate preferences compared with the wild type. • The first enzyme-ligand complex crystal structure of an IlvD/EDD superfamily enzyme was solved.
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Affiliation(s)
- Yaxin Ren
- Department of Chemistry, University of Eastern Finland, Joensuu Campus, PO BOX 111, 80101, Joensuu, Finland
| | - Elias Vettenranta
- Department of Chemistry, University of Eastern Finland, Joensuu Campus, PO BOX 111, 80101, Joensuu, Finland
| | - Leena Penttinen
- Department of Chemistry, University of Eastern Finland, Joensuu Campus, PO BOX 111, 80101, Joensuu, Finland
| | | | - Anu Koivula
- VTT Technical Research Centre of Finland Ltd, Espoo, Finland
| | - Juha Rouvinen
- Department of Chemistry, University of Eastern Finland, Joensuu Campus, PO BOX 111, 80101, Joensuu, Finland
| | - Nina Hakulinen
- Department of Chemistry, University of Eastern Finland, Joensuu Campus, PO BOX 111, 80101, Joensuu, Finland.
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3
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Rupert PB, Buerger M, Friend DJ, Strong RK. Structural elucidation of the mesothelin-mucin-16/CA125 interaction. Structure 2024; 32:1049-1054.e2. [PMID: 38703776 PMCID: PMC11316652 DOI: 10.1016/j.str.2024.04.011] [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: 01/18/2024] [Revised: 02/24/2024] [Accepted: 04/09/2024] [Indexed: 05/06/2024]
Abstract
Mesothelin (MSLN) is a cell-surface glycoprotein expressed at low levels on normal mesothelium but overexpressed in many cancers. Mesothelin has been implicated to play role/s in cell adhesion and multiple signaling pathways. Mucin-16/CA125 is an enormous cell-surface glycoprotein, also normally expressed on mesothelium and implicated in the progression and metastasis of several cancers, and directly binds mesothelin. However, the precise biological function/s of mesothelin and mucin-16/CA125 remain mysterious. We report protein engineering and recombinant production, qualitative and quantitative binding studies, and a crystal structure determination elucidating the molecular-level details governing recognition of mesothelin by mucin-16/CA125. The interface is small, consistent with the ∼micromolar binding constant and is free of glycan-mediated interactions. Sequence comparisons and modeling suggest that multiple mucin-16/CA125 modules can interact with mesothelin through comparable interactions, potentially generating a high degree of avidity at the cell surface to overcome the weak affinity, with implications for functioning and therapeutic interventions.
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Affiliation(s)
- Peter B Rupert
- Division of Basic Science, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Matthew Buerger
- Division of Basic Science, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Della J Friend
- Division of Basic Science, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Roland K Strong
- Division of Basic Science, Fred Hutchinson Cancer Center, Seattle, WA, USA.
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4
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Ihara M, Tsuchida N, Sumida M, Himiyama T, Kitayama T, Shirasaka N, Fukuta Y. Crystal Structure of the Native Chromoprotein from Pleurotus salmoneostramineus Provides Insights into the Pigmentation Mechanism. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:17626-17632. [PMID: 39073883 PMCID: PMC11311226 DOI: 10.1021/acs.jafc.4c02951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Revised: 06/29/2024] [Accepted: 07/02/2024] [Indexed: 07/31/2024]
Abstract
The pink-colored protein from the fungus Pleurotus salmoneostramineus (PsPCP) possesses unusual primary sequences with little resemblance to those of known proteins and exhibits a red color in aqueous solution. To understand the pigmentation mechanism of PsPCP, we elucidated the X-ray crystal structure of the native PsPCP. We identified a highly conjugated polyene ligand 2-dehydro-3-deoxylaetiporic acid A as a chromophore ligand, whose solution exhibits yellow. The crystal structure of PsPCP indicated that the ligand is secured in the central cavity and anchored at both termini by hydrophilic interactions and that surrounding residues show CH-pi and C-H···O hydrogen bondings. Geometrical analyses of the bound ligand demonstrated that the conjugated C-C and C═C bonds exhibit similar bond distances. The result indicated enhanced electron delocalization within the conjugated CC bond system, resulting in a redshift of the chromophore ligand. The computational estimates of the UV-vis spectra support the view that the electron delocalization within the conjugated CC bonds system of the bound ligand, induced by the specific ligand geometry within a limited space of PsPCP cavity, is responsible for the red pigmentation of PsPCP. Thus, we propose that the coloring mechanism of PsPCP, which constrains the geometry of a highly conjugated polyene ligand, is a novel type of pigment chemistry.
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Affiliation(s)
- Makoto Ihara
- Faculty
of Agriculture, Kindai University, 3327-204 Nakamachi, Nara, Nara 631-8505, Japan
| | - Noriko Tsuchida
- Faculty
of Medicine, Saitama Medical University, 38 Moroyama, Saitama 350-8550, Japan
| | - Marina Sumida
- Faculty
of Agriculture, Kindai University, 3327-204 Nakamachi, Nara, Nara 631-8505, Japan
| | - Tomoki Himiyama
- National
Institute of Advanced Industrial Science and Technology, 1-8-31, Midorigaoka, Ikeda, Osaka 563-8577, Japan
| | - Takashi Kitayama
- Faculty
of Agriculture, Kindai University, 3327-204 Nakamachi, Nara, Nara 631-8505, Japan
| | - Norifumi Shirasaka
- Faculty
of Agriculture, Kindai University, 3327-204 Nakamachi, Nara, Nara 631-8505, Japan
| | - Yasuhisa Fukuta
- Faculty
of Agriculture, Kindai University, 3327-204 Nakamachi, Nara, Nara 631-8505, Japan
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5
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Moriarty NW, Moussa J, Adams PD. Protonation of histidine rings using quantum-mechanical methods. Acta Crystallogr D Struct Biol 2024; 80:639-646. [PMID: 39052316 DOI: 10.1107/s2059798324006314] [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: 03/01/2024] [Accepted: 06/27/2024] [Indexed: 07/27/2024] Open
Abstract
Histidine can be protonated on either or both of the two N atoms of the imidazole moiety. Each of the three possible forms occurs as a result of the stereochemical environment of the histidine side chain. In an atomic model, comparing the possible protonation states in situ, looking at possible hydrogen bonding and metal coordination, it is possible to predict which is most likely to be correct. A more direct method is described that uses quantum-mechanical methods to calculate, also in situ, the minimum geometry and energy for comparison, and therefore to more accurately identify the most likely protonation state.
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Affiliation(s)
- Nigel W Moriarty
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Jonathan Moussa
- Molecular Sciences Software Institute, Virginia Tech, Blacksburg, VA 24060, USA
| | - Paul D Adams
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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6
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Sevrioukova IF. Interaction of CYP3A4 with the inhibitor cobicistat: Structural and mechanistic insights and comparison with ritonavir. Arch Biochem Biophys 2024; 758:110071. [PMID: 38909836 PMCID: PMC11286144 DOI: 10.1016/j.abb.2024.110071] [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: 04/17/2024] [Revised: 06/20/2024] [Accepted: 06/21/2024] [Indexed: 06/25/2024]
Abstract
Cobicistat is a derivative of ritonavir marketed as a pharmacoenhancer for anti-HIV therapy. This study investigated the interaction of cobicistat with the target protein, drug-metabolizing cytochrome P450 3A4 (CYP3A4), at the molecular level using spectral, kinetic, functional, and structural approaches. It was found that, similar to ritonavir, cobicistat directly coordinates to the heme via the thiazole nitrogen but its affinity and the binding rate are 2-fold lower: 0.030 μM and 0.72 s-1, respectively. The newly determined 2.5 Å crystal structure of cobicistat-bound CYP3A4 suggests that these changes arise from the inability of cobicistat to H-bond to the active site S119 and establish multiple stabilizing contacts with the F-F' connecting fragment, which becomes disordered upon steric clashing with the bulky morpholine moiety. Nonetheless, cobicistat inhibits recombinant CYP3A4 as potently as ritonavir (IC50 of 0.24 μM vs 0.22 μM, respectively) due to strong ligation to the heme and formation of extensive hydrophobic/aromatic interactions via the phenyl side-groups. To get insights into the inhibitory mechanism, the K257 residue, known to be solely and irreversibly modified by the reactive ritonavir metabolite, was substituted with alanine. Neither this nor control K266A mutation changed the extent of time-dependent inhibition of CYP3A4 by cobicistat and ritonavir, suggesting the existence of alternative inactivation mechanism(s). More importantly, K257 was found to be functionally important and contributed to CYP3A4 allosterism, possibly by modulating protein-ligand interactions through conformational dynamics.
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Affiliation(s)
- Irina F Sevrioukova
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, 92697-3900, USA.
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7
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Dampalla CS, Kim Y, Zabiegala A, Howard DJ, Nguyen HN, Madden TK, Thurman HA, Cooper A, Liu L, Battaile KP, Lovell S, Chang KO, Groutas WC. Structure-Guided Design of Potent Coronavirus Inhibitors with a 2-Pyrrolidone Scaffold: Biochemical, Crystallographic, and Virological Studies. J Med Chem 2024; 67:11937-11956. [PMID: 38953866 DOI: 10.1021/acs.jmedchem.4c00551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/04/2024]
Abstract
Zoonotic coronaviruses are known to produce severe infections in humans and have been the cause of significant morbidity and mortality worldwide. SARS-CoV-2 was the largest and latest contributor of fatal cases, even though MERS-CoV has the highest case-fatality ratio among zoonotic coronaviruses. These infections pose a high risk to public health worldwide warranting efforts for the expeditious discovery of antivirals. Hence, we hereby describe a novel series of inhibitors of coronavirus 3CLpro embodying an N-substituted 2-pyrrolidone scaffold envisaged to exploit favorable interactions with the S3-S4 subsites and connected to an invariant Leu-Gln P2-P1 recognition element. Several inhibitors showed nanomolar antiviral activity in enzyme and cell-based assays, with no significant cytotoxicity. High-resolution crystal structures of inhibitors bound to the 3CLpro were determined to probe and identify the molecular determinants associated with binding, to inform the structure-guided optimization of the inhibitors, and to confirm the mechanism of action of the inhibitors.
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Affiliation(s)
- Chamandi S Dampalla
- Department of Chemistry and Biochemistry, Wichita State University, Wichita, Kansas 67260, United States
| | - Yunjeong Kim
- Department of Diagnostic Medicine & Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas 66506, United States
| | - Alexandria Zabiegala
- Department of Diagnostic Medicine & Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas 66506, United States
| | - Dennis J Howard
- Department of Chemistry and Biochemistry, Wichita State University, Wichita, Kansas 67260, United States
| | - Harry Nhat Nguyen
- Department of Chemistry and Biochemistry, Wichita State University, Wichita, Kansas 67260, United States
| | - Trent K Madden
- Department of Chemistry and Biochemistry, Wichita State University, Wichita, Kansas 67260, United States
| | - Hayden A Thurman
- Department of Chemistry and Biochemistry, Wichita State University, Wichita, Kansas 67260, United States
| | - Anne Cooper
- Protein Structure and X-ray Crystallography Laboratory, The University of Kansas, Lawrence, Kansas 66047, United States
| | - Lijun Liu
- Protein Structure and X-ray Crystallography Laboratory, The University of Kansas, Lawrence, Kansas 66047, United States
| | - Kevin P Battaile
- NYX, New York Structural Biology Center, Upton, New York 11973, United States
| | - Scott Lovell
- Protein Structure and X-ray Crystallography Laboratory, The University of Kansas, Lawrence, Kansas 66047, United States
| | - Kyeong-Ok Chang
- Department of Diagnostic Medicine & Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas 66506, United States
| | - William C Groutas
- Department of Chemistry and Biochemistry, Wichita State University, Wichita, Kansas 67260, United States
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8
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Maschio L, Back CR, Alnawah J, Bowen JI, Johns ST, Mbatha SZ, Han LC, Lees NR, Zorn K, Stach JEM, Hayes MA, van der Kamp MW, Pudney CR, Burston SG, Willis CL, Race PR. Delineation of the complete reaction cycle of a natural Diels-Alderase. Chem Sci 2024; 15:11572-11583. [PMID: 39055018 PMCID: PMC11268479 DOI: 10.1039/d4sc02908a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2024] [Accepted: 06/19/2024] [Indexed: 07/27/2024] Open
Abstract
The Diels-Alder reaction is one of the most effective methods for the synthesis of substituted cyclohexenes. The development of protein catalysts for this reaction remains a major priority, affording new sustainable routes to high value target molecules. Whilst a small number of natural enzymes have been shown capable of catalysing [4 + 2] cycloadditions, there is a need for significant mechanistic understanding of how these prospective Diels-Alderases promote catalysis to underpin their development as biocatalysts for use in synthesis. Here we present a molecular description of the complete reaction cycle of the bona fide natural Diels-Alderase AbyU, which catalyses formation of the spirotetronate skeleton of the antibiotic abyssomicin C. This description is derived from X-ray crystallographic studies of AbyU in complex with a non-transformable synthetic substrate analogue, together with transient kinetic analyses of the AbyU catalysed reaction and computational reaction simulations. These studies reveal the mechanistic intricacies of this enzyme system and establish a foundation for the informed reengineering of AbyU and related biocatalysts.
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Affiliation(s)
- Laurence Maschio
- School of Biochemistry, University Walk, University of Bristol BS8 1TD UK
| | - Catherine R Back
- School of Biochemistry, University Walk, University of Bristol BS8 1TD UK
| | - Jawaher Alnawah
- School of Chemistry, University of Bristol Cantock's Close BS8 1TS UK
- Department of Chemistry, King Faisal University, College of Science Al-Ahsa 31982 Saudi Arabia
| | - James I Bowen
- School of Chemistry, University of Bristol Cantock's Close BS8 1TS UK
| | - Samuel T Johns
- School of Biochemistry, University Walk, University of Bristol BS8 1TD UK
| | | | - Li-Chen Han
- School of Chemistry, University of Bristol Cantock's Close BS8 1TS UK
| | - Nicholas R Lees
- School of Chemistry, University of Bristol Cantock's Close BS8 1TS UK
| | - Katja Zorn
- Discovery Sciences, Biopharmaceuticals R&D, AstraZeneca Pepparedsleden 1 431 83 Mölndal Sweden
| | - James E M Stach
- School of Natural and Environmental Sciences, Newcastle University NE1 7RU UK
| | - Martin A Hayes
- Discovery Sciences, Biopharmaceuticals R&D, AstraZeneca Pepparedsleden 1 431 83 Mölndal Sweden
| | | | - Christopher R Pudney
- Department of Biology and Biochemistry, University of Bath Claverton Down BA2 7AY UK
| | - Steven G Burston
- School of Biochemistry, University Walk, University of Bristol BS8 1TD UK
| | | | - Paul R Race
- School of Natural and Environmental Sciences, Newcastle University NE1 7RU UK
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9
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Prester A, Perbandt M, Galchenkova M, Oberthuer D, Werner N, Henkel A, Maracke J, Yefanov O, Hakanpää J, Pompidor G, Meyer J, Chapman H, Aepfelbacher M, Hinrichs W, Rohde H, Betzel C. Time-resolved crystallography of boric acid binding to the active site serine of the β-lactamase CTX-M-14 and subsequent 1,2-diol esterification. Commun Chem 2024; 7:152. [PMID: 38969718 PMCID: PMC11226702 DOI: 10.1038/s42004-024-01236-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Accepted: 06/27/2024] [Indexed: 07/07/2024] Open
Abstract
The emergence and spread of antibiotic resistance represent a growing threat to public health. Of particular concern is the appearance of β-lactamases, which are capable to hydrolyze and inactivate the most important class of antibiotics, the β-lactams. Effective β-lactamase inhibitors and mechanistic insights into their action are central in overcoming this type of resistance, and in this context boronate-based β-lactamase inhibitors were just recently approved to treat multidrug-resistant bacteria. Using boric acid as a simplified inhibitor model, time-resolved serial crystallography was employed to obtain mechanistic insights into binding to the active site serine of β-lactamase CTX-M-14, identifying a reaction time frame of 80-100 ms. In a next step, the subsequent 1,2-diol boric ester formation with glycerol in the active site was monitored proceeding in a time frame of 100-150 ms. Furthermore, the displacement of the crucial anion in the active site of the β-lactamase was verified as an essential part of the binding mechanism of substrates and inhibitors. In total, 22 datasets of β-lactamase intermediate complexes with high spatial resolution of 1.40-2.04 Å and high temporal resolution range of 50-10,000 ms were obtained, allowing a detailed analysis of the studied processes. Mechanistic details captured here contribute to the understanding of molecular processes and their time frames in enzymatic reactions. Moreover, we could demonstrate that time-resolved crystallography can serve as an additional tool for identifying and investigating enzymatic reactions.
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Affiliation(s)
- Andreas Prester
- Institute of Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf UKE, Hamburg, Germany
- Institute of Biochemistry and Signal Transduction, University Medical Center Hamburg-Eppendorf UKE, Hamburg, Germany
| | - Markus Perbandt
- Institute of Biochemistry and Molecular Biology, University of Hamburg, Hamburg, Germany
| | | | | | - Nadine Werner
- Institute of Biochemistry and Molecular Biology, University of Hamburg, Hamburg, Germany
- Centre for Integrative Biology, Department of Integrated Structural Biology, Institute of Genetics, Molecular and Cellular Biology, IGBMC, Illkirch, France
| | | | - Julia Maracke
- Center for Free-Electron Laser Science CFEL, DESY, Hamburg, Germany
| | | | | | | | - Jan Meyer
- Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany
| | - Henry Chapman
- Center for Free-Electron Laser Science CFEL, DESY, Hamburg, Germany
- Hamburg Centre for Ultrafast Imaging CUI, University of Hamburg, Hamburg, Germany
- Department of Physics, University of Hamburg, Hamburg, Germany
| | - Martin Aepfelbacher
- Institute of Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf UKE, Hamburg, Germany
| | - Winfried Hinrichs
- Institute of Biochemistry, University of Greifswald, Greifswald, Germany
| | - Holger Rohde
- Institute of Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf UKE, Hamburg, Germany.
| | - Christian Betzel
- Institute of Biochemistry and Molecular Biology, University of Hamburg, Hamburg, Germany.
- Hamburg Centre for Ultrafast Imaging CUI, University of Hamburg, Hamburg, Germany.
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10
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Umezawa A, Matsumoto M, Handa H, Nakazawa K, Miyagawa M, Seifert GJ, Takahashi D, Fushinobu S, Kotake T. Cytosolic UDP-L-arabinose synthesis by bifunctional UDP-glucose 4-epimerases in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 119:508-524. [PMID: 38678521 DOI: 10.1111/tpj.16779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 03/20/2024] [Accepted: 04/04/2024] [Indexed: 05/01/2024]
Abstract
L-Arabinose (L-Ara) is a plant-specific sugar found in cell wall polysaccharides, proteoglycans, glycoproteins, and small glycoconjugates, which play physiologically important roles in cell proliferation and other essential cellular processes. L-Ara is synthesized as UDP-L-arabinose (UDP-L-Ara) from UDP-xylose (UDP-Xyl) by UDP-Xyl 4-epimerases (UXEs), a type of de novo synthesis of L-Ara unique to plants. In Arabidopsis, the Golgi-localized UXE AtMUR4 is the main contributor to UDP-L-Ara synthesis. However, cytosolic bifunctional UDP-glucose 4-epimerases (UGEs) with UXE activity, AtUGE1, and AtUGE3 also catalyze this reaction. For the present study, we first examined the physiological importance of bifunctional UGEs in Arabidopsis. The uge1 and uge3 mutants enhanced the dwarf phenotype of mur4 and further reduced the L-Ara content in cell walls, suggesting that bifunctional UGEs contribute to UDP-L-Ara synthesis. Through the introduction of point mutations exchanging corresponding amino acid residues between AtUGE1 with high UXE activity and AtUGE2 with low UXE activity, two mutations that increase relative UXE activity of AtUGE2 were identified. The crystal structures of AtUGE2 in complex forms with NAD+ and NAD+/UDP revealed that the UDP-binding domain of AtUGE2 has a more closed conformation and smaller sugar-binding site than bacterial and mammalian UGEs, suggesting that plant UGEs have the appropriate size and shape for binding UDP-Xyl and UDP-L-Ara to exhibit UXE activity. The presented results suggest that the capacity for cytosolic synthesis of UDP-L-Ara was acquired by the small sugar-binding site and several mutations of UGEs, enabling diversified utilization of L-Ara in seed plants.
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Affiliation(s)
- Akira Umezawa
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, 255 Shimo-okubo, Sakura-ku, Saitama, 338-8570, Japan
| | - Mayuko Matsumoto
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, Japan
| | - Hiroto Handa
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, 255 Shimo-okubo, Sakura-ku, Saitama, 338-8570, Japan
| | - Konatsu Nakazawa
- Department of Biochemistry and Molecular Biology, Saitama University, 255 Shimo-okubo, Sakura-ku, Saitama, 338-8570, Japan
| | - Megumi Miyagawa
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, 255 Shimo-okubo, Sakura-ku, Saitama, 338-8570, Japan
| | - Georg J Seifert
- Institute of Plant Biotechnology and Cell biology, University of Natural Resources and Life Science, Muthgasse 18, A-1190, Vienna, Austria
| | - Daisuke Takahashi
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, 255 Shimo-okubo, Sakura-ku, Saitama, 338-8570, Japan
| | - Shinya Fushinobu
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, Japan
| | - Toshihisa Kotake
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, 255 Shimo-okubo, Sakura-ku, Saitama, 338-8570, Japan
- Green Bioscience Research Center, Saitama University, 255 Shimo-okubo, Sakura-ku, Saitama, 338-8570, Japan
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11
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Vallejos A, Katona G, Neutze R. Appraising protein conformational changes by resampling time-resolved serial x-ray crystallography data. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2024; 11:044302. [PMID: 39056073 PMCID: PMC11272219 DOI: 10.1063/4.0000258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Accepted: 06/28/2024] [Indexed: 07/28/2024]
Abstract
With the development of serial crystallography at both x-ray free electron laser and synchrotron radiation sources, time-resolved x-ray crystallography is increasingly being applied to study conformational changes in macromolecules. A successful time-resolved serial crystallography study requires the growth of microcrystals, a mechanism for synchronized and homogeneous excitation of the reaction of interest within microcrystals, and tools for structural interpretation. Here, we utilize time-resolved serial femtosecond crystallography data collected from microcrystals of bacteriorhodopsin to compare results from partial occupancy structural refinement and refinement against extrapolated data. We illustrate the domain wherein the amplitude of refined conformational changes is inversely proportional to the activated state occupancy. We illustrate how resampling strategies allow coordinate uncertainty to be estimated and demonstrate that these two approaches to structural refinement agree within coordinate errors. We illustrate how singular value decomposition of a set of difference Fourier electron density maps calculated from resampled data can minimize phase bias in these maps, and we quantify residual densities for transient water molecules by analyzing difference Fourier and Polder omit maps from resampled data. We suggest that these tools may assist others in judging the confidence with which observed electron density differences may be interpreted as functionally important conformational changes.
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Affiliation(s)
- Adams Vallejos
- Department of Chemistry and Molecular Biology, University of Gothenburg, Box 462, 40530 Gothenburg, Sweden
| | - Gergely Katona
- Department of Chemistry and Molecular Biology, University of Gothenburg, Box 462, 40530 Gothenburg, Sweden
| | - Richard Neutze
- Department of Chemistry and Molecular Biology, University of Gothenburg, Box 462, 40530 Gothenburg, Sweden
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12
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Meeks KR, Bogner AN, Tanner JJ. Screening a knowledge-based library of low molecular weight compounds against the proline biosynthetic enzyme 1-pyrroline-5-carboxylate 1 (PYCR1). Protein Sci 2024; 33:e5072. [PMID: 39133178 DOI: 10.1002/pro.5072] [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: 04/12/2024] [Revised: 05/21/2024] [Accepted: 05/24/2024] [Indexed: 08/13/2024]
Abstract
Δ1-pyrroline-5-carboxylate reductase isoform 1 (PYCR1) is the last enzyme of proline biosynthesis and catalyzes the NAD(P)H-dependent reduction of Δ1-pyrroline-5-carboxylate to L-proline. High PYCR1 gene expression is observed in many cancers and linked to poor patient outcomes and tumor aggressiveness. The knockdown of the PYCR1 gene or the inhibition of PYCR1 enzyme has been shown to inhibit tumorigenesis in cancer cells and animal models of cancer, motivating inhibitor discovery. We screened a library of 71 low molecular weight compounds (average MW of 131 Da) against PYCR1 using an enzyme activity assay. Hit compounds were validated with X-ray crystallography and kinetic assays to determine affinity parameters. The library was counter-screened against human Δ1-pyrroline-5-carboxylate reductase isoform 3 and proline dehydrogenase (PRODH) to assess specificity/promiscuity. Twelve PYCR1 and one PRODH inhibitor crystal structures were determined. Three compounds inhibit PYCR1 with competitive inhibition parameter of 100 μM or lower. Among these, (S)-tetrahydro-2H-pyran-2-carboxylic acid (70 μM) has higher affinity than the current best tool compound N-formyl-l-proline, is 30 times more specific for PYCR1 over human Δ1-pyrroline-5-carboxylate reductase isoform 3, and negligibly inhibits PRODH. Structure-affinity relationships suggest that hydrogen bonding of the heteroatom of this compound is important for binding to PYCR1. The structures of PYCR1 and PRODH complexed with 1-hydroxyethane-1-sulfonate demonstrate that the sulfonate group is a suitable replacement for the carboxylate anchor. This result suggests that the exploration of carboxylic acid isosteres may be a promising strategy for discovering new classes of PYCR1 and PRODH inhibitors. The structure of PYCR1 complexed with l-pipecolate and NADH supports the hypothesis that PYCR1 has an alternative function in lysine metabolism.
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Affiliation(s)
- Kaylen R Meeks
- Department of Biochemistry, University of Missouri, Columbia, Missouri, USA
| | - Alexandra N Bogner
- Department of Biochemistry, University of Missouri, Columbia, Missouri, USA
| | - John J Tanner
- Department of Biochemistry, University of Missouri, Columbia, Missouri, USA
- Department of Chemistry, University of Missouri, Columbia, Missouri, USA
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13
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Burata OE, O'Donnell E, Hyun J, Lucero RM, Thomas JE, Gibbs EM, Reacher I, Carney NA, Stockbridge RB. Peripheral positions encode transport specificity in the small multidrug resistance exporters. Proc Natl Acad Sci U S A 2024; 121:e2403273121. [PMID: 38865266 PMCID: PMC11194549 DOI: 10.1073/pnas.2403273121] [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: 02/19/2024] [Accepted: 05/02/2024] [Indexed: 06/14/2024] Open
Abstract
In secondary active transporters, a relatively limited set of protein folds have evolved diverse solute transport functions. Because of the conformational changes inherent to transport, altering substrate specificity typically involves remodeling the entire structural landscape, limiting our understanding of how novel substrate specificities evolve. In the current work, we examine a structurally minimalist family of model transport proteins, the small multidrug resistance (SMR) transporters, to understand the molecular basis for the emergence of a novel substrate specificity. We engineer a selective SMR protein to promiscuously export quaternary ammonium antiseptics, similar to the activity of a clade of multidrug exporters in this family. Using combinatorial mutagenesis and deep sequencing, we identify the necessary and sufficient molecular determinants of this engineered activity. Using X-ray crystallography, solid-supported membrane electrophysiology, binding assays, and a proteoliposome-based quaternary ammonium antiseptic transport assay that we developed, we dissect the mechanistic contributions of these residues to substrate polyspecificity. We find that substrate preference changes not through modification of the residues that directly interact with the substrate but through mutations peripheral to the binding pocket. Our work provides molecular insight into substrate promiscuity among the SMRs and can be applied to understand multidrug export and the evolution of novel transport functions more generally.
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Affiliation(s)
- Olive E Burata
- Program in Chemical Biology, University of Michigan, Ann Arbor, MI 48109
| | - Ever O'Donnell
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109
| | - Jeonghoon Hyun
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109
| | - Rachael M Lucero
- Program in Chemical Biology, University of Michigan, Ann Arbor, MI 48109
| | - Junius E Thomas
- Program in Chemical Biology, University of Michigan, Ann Arbor, MI 48109
| | - Ethan M Gibbs
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109
| | - Isabella Reacher
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109
| | - Nolan A Carney
- Program in Chemical Biology, University of Michigan, Ann Arbor, MI 48109
| | - Randy B Stockbridge
- Program in Chemical Biology, University of Michigan, Ann Arbor, MI 48109
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109
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14
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Muñoz SM, Vallejos-Baccelliere G, Manubens A, Salazar ML, Nascimento AFZ, Tapia-Reyes P, Meneses C, Ambrosio ALB, Becker MI, Guixé V, Castro-Fernandez V. Structural insights into a functional unit from an immunogenic mollusk hemocyanin. Structure 2024; 32:812-823.e4. [PMID: 38513659 DOI: 10.1016/j.str.2024.02.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 01/30/2024] [Accepted: 02/23/2024] [Indexed: 03/23/2024]
Abstract
Mollusk hemocyanins, among the largest known proteins, are used as immunostimulants in biomedical and clinical applications. The hemocyanin of the Chilean gastropod Concholepas concholepas (CCH) exhibits unique properties, which makes it safe and effective for human immunotherapy, as observed in animal models of bladder cancer and melanoma, and dendritical cell vaccine trials. Despite its potential, the structure and amino acid sequence of CCH remain unknown. This study reports two sequence fragments of CCH, representing three complete functional units (FUs). We also determined the high-resolution (1.5 Å) X-ray crystal structure of an "FU-g type" from the CCHB subunit. This structure enables in-depth analysis of chemical interactions at the copper-binding center and unveils an unusual, truncated N-glycosylation pattern. These features are linked to eliciting more robust immunological responses in animals, offering insights into CCH's enhanced immunostimulatory properties and opening new avenues for its potential applications in biomedical research and therapies.
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Affiliation(s)
- Sebastián M Muñoz
- Laboratorio de Bioquímica y Biología Molecular, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago 780003, Chile
| | - Gabriel Vallejos-Baccelliere
- Laboratorio de Bioquímica y Biología Molecular, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago 780003, Chile
| | - Augusto Manubens
- Departamento de Investigación y Desarrollo, Biosonda Corp., Santiago 7750629, Chile; Fundación Ciencia y Tecnología para el Desarrollo (FUCITED), Santiago 7750629, Chile
| | - Michelle L Salazar
- Fundación Ciencia y Tecnología para el Desarrollo (FUCITED), Santiago 7750629, Chile
| | - Andrey F Z Nascimento
- Brazilian Synchrotron Light Laboratory (LNLS), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, Sao Paulo 13083-970, Brazil
| | - Patricio Tapia-Reyes
- Escuela de Biotecnología, Facultad de Ciencias, Universidad Santo Tomás, Santiago 8370003, Chile; Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
| | - Claudio Meneses
- Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile; Departamento de Fruticultura y Enología, Facultad de Agronomía y Sistemas Naturales, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile; Millennium Nucleus Development of Super Adaptable Plants (MN-SAP), Santiago 8331150, Chile; Millennium Institute Center for Genome Regulation (CRG), Santiago 8331150, Chile
| | - Andre L B Ambrosio
- Sao Carlos Institute of Physics (IFSC), University of Sao Paulo (USP), Sao Carlos, Sao Paulo 13563-120, Brazil
| | - María Inés Becker
- Departamento de Investigación y Desarrollo, Biosonda Corp., Santiago 7750629, Chile; Fundación Ciencia y Tecnología para el Desarrollo (FUCITED), Santiago 7750629, Chile
| | - Victoria Guixé
- Laboratorio de Bioquímica y Biología Molecular, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago 780003, Chile.
| | - Victor Castro-Fernandez
- Laboratorio de Bioquímica y Biología Molecular, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago 780003, Chile.
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15
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Fujiwara T, Mano E, Nango E. Structural basis for the minimal bifunctional alginate epimerase AlgE3 from Azotobacter chroococcum. FEBS Lett 2024; 598:1422-1437. [PMID: 38649293 DOI: 10.1002/1873-3468.14886] [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: 01/23/2024] [Revised: 03/15/2024] [Accepted: 03/23/2024] [Indexed: 04/25/2024]
Abstract
Among the epimerases specific to alginate, some of them in Azotobacter genera convert β-d-mannuronic acid to α-l-guluronic acid but also have lyase activity to degrade alginate. The remarkable characteristics of these epimerases make it a promising enzyme for tailoring alginates to meet specific demands. Here, we determined the structure of the bifunctional mannuronan C-5 epimerase AlgE3 from Azotobacter chroococcum (AcAlgE3) in complex with several mannuronic acid oligomers as well as in apo form, which allowed us to elucidate the binding manner of each mannuronic acid oligomer, and the structural plasticity, which is dependent on calcium ions. Moreover, a comprehensive analysis of the lyase activity profiles of AcAlgE3 combined with structural characteristics explained the preference for different chain length oligomers.
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Affiliation(s)
- Takaaki Fujiwara
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai, Japan
| | - Eriko Mano
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai, Japan
| | - Eriko Nango
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai, Japan
- RIKEN SPring-8 Center, Sayo-gun, Japan
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16
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Lublin V, Kauffmann B, Engilberge S, Durola F, Gounel S, Bichon S, Jean C, Mano N, Giraud MF, Chavas L, Thureau A, Thompson A, Stines-Chaumeil C. Does Acinetobacter calcoaceticus glucose dehydrogenase produce self-damaging H2O2? Biosci Rep 2024; 44:BSR20240102. [PMID: 38687614 PMCID: PMC11130540 DOI: 10.1042/bsr20240102] [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: 01/26/2024] [Revised: 04/25/2024] [Accepted: 04/30/2024] [Indexed: 05/02/2024] Open
Abstract
The soluble glucose dehydrogenase (sGDH) from Acinetobacter calcoaceticus has been widely studied and is used, in biosensors, to detect the presence of glucose, taking advantage of its high turnover and insensitivity to molecular oxygen. This approach, however, presents two drawbacks: the enzyme has broad substrate specificity (leading to imprecise blood glucose measurements) and shows instability over time (inferior to other oxidizing glucose enzymes). We report the characterization of two sGDH mutants: the single mutant Y343F and the double mutant D143E/Y343F. The mutants present enzyme selectivity and specificity of 1.2 (Y343F) and 5.7 (D143E/Y343F) times higher for glucose compared with that of the wild-type. Crystallographic experiments, designed to characterize these mutants, surprisingly revealed that the prosthetic group PQQ (pyrroloquinoline quinone), essential for the enzymatic activity, is in a cleaved form for both wild-type and mutant structures. We provide evidence suggesting that the sGDH produces H2O2, the level of production depending on the mutation. In addition, spectroscopic experiments allowed us to follow the self-degradation of the prosthetic group and the disappearance of sGDH's glucose oxidation activity. These studies suggest that the enzyme is sensitive to its self-production of H2O2. We show that the premature aging of sGDH can be slowed down by adding catalase to consume the H2O2 produced, allowing the design of a more stable biosensor over time. Our research opens questions about the mechanism of H2O2 production and the physiological role of this activity by sGDH.
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Affiliation(s)
- Victoria Lublin
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
- Synchrotron SOLEIL (CNRS - CEA), Saint-Aubin, France
| | - Brice Kauffmann
- Institut Européen de Chimie et Biologie (IECB), Univ. Bordeaux, CNRS, INSERM, US1, UAR 3033, Pessac, France
| | - Sylvain Engilberge
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale (IBS), 71 avenue des Martyrs, Grenoble 38044, France
| | - Fabien Durola
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
| | - Sébastien Gounel
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
| | - Sabrina Bichon
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
| | - Cloée Jean
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
| | - Nicolas Mano
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
| | - Marie-France Giraud
- Institute of Chemistry and Biology of Membranes and Nano-objects (CBMN), Pessac, France
| | | | | | | | - Claire Stines-Chaumeil
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
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17
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Vulpetti A, Rondeau JM, Bellance MH, Blank J, Boesch R, Boettcher A, Bornancin F, Buhr S, Connor LE, Dumelin CE, Esser O, Hediger M, Hintermann S, Hommel U, Koch E, Lapointe G, Leder L, Lehmann S, Lehr P, Meier P, Muller L, Ostermeier D, Ramage P, Schiebel-Haddad S, Smith AB, Stojanovic A, Velcicky J, Yamamoto R, Hurth K. Ligandability Assessment of IL-1β by Integrated Hit Identification Approaches. J Med Chem 2024; 67:8141-8160. [PMID: 38728572 DOI: 10.1021/acs.jmedchem.4c00240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2024]
Abstract
Human interleukin-1β (IL-1β) is a pro-inflammatory cytokine that plays a critical role in the regulation of the immune response and the development of various inflammatory diseases. In this publication, we disclose our efforts toward the discovery of IL-1β binders that interfere with IL-1β signaling. To this end, several technologies were used in parallel, including fragment-based screening (FBS), DNA-encoded library (DEL) technology, peptide discovery platform (PDP), and virtual screening. The utilization of distinct technologies resulted in the identification of new chemical entities exploiting three different sites on IL-1β, all of them also inhibiting the interaction with the IL-1R1 receptor. Moreover, we identified lysine 103 of IL-1β as a target residue suitable for the development of covalent, low-molecular-weight IL-1β antagonists.
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Affiliation(s)
- Anna Vulpetti
- Biomedical Research, Novartis, CH-4002 Basel, Switzerland
| | | | | | - Jutta Blank
- Biomedical Research, Novartis, CH-4002 Basel, Switzerland
| | - Ralf Boesch
- Biomedical Research, Novartis, CH-4002 Basel, Switzerland
| | | | | | - Sylvia Buhr
- Biomedical Research, Novartis, CH-4002 Basel, Switzerland
| | | | | | - Oliver Esser
- Biomedical Research, Novartis, CH-4002 Basel, Switzerland
| | | | | | - Ulrich Hommel
- Biomedical Research, Novartis, CH-4002 Basel, Switzerland
| | - Elke Koch
- Biomedical Research, Novartis, CH-4002 Basel, Switzerland
| | | | - Lukas Leder
- Biomedical Research, Novartis, CH-4002 Basel, Switzerland
| | - Sylvie Lehmann
- Biomedical Research, Novartis, CH-4002 Basel, Switzerland
| | - Philipp Lehr
- Biomedical Research, Novartis, CH-4002 Basel, Switzerland
| | - Peter Meier
- Biomedical Research, Novartis, CH-4002 Basel, Switzerland
| | - Lionel Muller
- Biomedical Research, Novartis, CH-4002 Basel, Switzerland
| | | | - Paul Ramage
- Biomedical Research, Novartis, CH-4002 Basel, Switzerland
| | | | | | | | - Juraj Velcicky
- Biomedical Research, Novartis, CH-4002 Basel, Switzerland
| | - Rina Yamamoto
- Biomedical Research, Novartis, CH-4002 Basel, Switzerland
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18
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Smith OB, Frkic RL, Rahman MG, Jackson CJ, Kaczmarski JA. Identification and Characterization of a Bacterial Periplasmic Solute Binding Protein That Binds l-Amino Acid Amides. Biochemistry 2024; 63:1322-1334. [PMID: 38696389 DOI: 10.1021/acs.biochem.4c00096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2024]
Abstract
Periplasmic solute-binding proteins (SBPs) are key ligand recognition components of bacterial ATP-binding cassette (ABC) transporters that allow bacteria to import nutrients and metabolic precursors from the environment. Periplasmic SBPs comprise a large and diverse family of proteins, of which only a small number have been empirically characterized. In this work, we identify a set of 610 unique uncharacterized proteins within the SBP_bac_5 family that are found in conserved operons comprising genes encoding (i) ABC transport systems and (ii) putative amidases from the FmdA_AmdA family. From these uncharacterized SBP_bac_5 proteins, we characterize a representative periplasmic SBP from Mesorhizobium sp. A09 (MeAmi_SBP) and show that MeAmi_SBP binds l-amino acid amides but not the corresponding l-amino acids. An X-ray crystal structure of MeAmi_SBP bound to l-serinamide highlights the residues that impart distinct specificity for l-amino acid amides and reveals a structural Ca2+ binding site within one of the lobes of the protein. We show that the residues involved in ligand and Ca2+ binding are conserved among the 610 SBPs from experimentally uncharacterized FmdA_AmdA amidase-associated ABC transporter systems, suggesting these homologous systems are also likely to be involved in the sensing, uptake, and metabolism of l-amino acid amides across many Gram-negative nitrogen-fixing soil bacteria. We propose that MeAmi_SBP is involved in the uptake of such solutes to supplement pathways such as the citric acid cycle and the glutamine synthetase-glutamate synthase pathway. This work expands our currently limited understanding of microbial interactions with l-amino acid amides and bacterial nitrogen utilization.
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Affiliation(s)
- Oliver B Smith
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 2601, Australia
- ARC Centre of Excellence in Synthetic Biology, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Rebecca L Frkic
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 2601, Australia
- ARC Centre of Excellence for Innovations in Peptide & Protein Science, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Marina G Rahman
- ARC Centre of Excellence in Synthetic Biology, Australian National University, Canberra, Australian Capital Territory 2601, Australia
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Colin J Jackson
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 2601, Australia
- ARC Centre of Excellence in Synthetic Biology, Australian National University, Canberra, Australian Capital Territory 2601, Australia
- ARC Centre of Excellence for Innovations in Peptide & Protein Science, Australian National University, Canberra, Australian Capital Territory 2601, Australia
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Joe A Kaczmarski
- ARC Centre of Excellence in Synthetic Biology, Australian National University, Canberra, Australian Capital Territory 2601, Australia
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory 2601, Australia
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19
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Boverio A, Jamil N, Mannucci B, Mascotti ML, Fraaije MW, Mattevi A. Structure, mechanism, and evolution of the last step in vitamin C biosynthesis. Nat Commun 2024; 15:4158. [PMID: 38755143 PMCID: PMC11099136 DOI: 10.1038/s41467-024-48410-1] [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: 01/30/2024] [Accepted: 04/30/2024] [Indexed: 05/18/2024] Open
Abstract
Photosynthetic organisms, fungi, and animals comprise distinct pathways for vitamin C biosynthesis. Besides this diversity, the final biosynthetic step consistently involves an oxidation reaction carried out by the aldonolactone oxidoreductases. Here, we study the origin and evolution of the diversified activities and substrate preferences featured by these flavoenzymes using molecular phylogeny, kinetics, mutagenesis, and crystallographic experiments. We find clear evidence that they share a common ancestor. A flavin-interacting amino acid modulates the reactivity with the electron acceptors, including oxygen, and determines whether an enzyme functions as an oxidase or a dehydrogenase. We show that a few side chains in the catalytic cavity impart the reaction stereoselectivity. Ancestral sequence reconstruction outlines how these critical positions were affixed to specific amino acids along the evolution of the major eukaryotic clades. During Eukarya evolution, the aldonolactone oxidoreductases adapted to the varying metabolic demands while retaining their overarching vitamin C-generating function.
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Affiliation(s)
- Alessandro Boverio
- Molecular Enzymology group, University of Groningen, Nijenborgh 4, 9747AG, Groningen, The Netherlands
- Department of Biology and Biotechnology, University of Pavia, via Ferrata 9, 27100, Pavia, Italy
| | - Neelam Jamil
- Department of Biology and Biotechnology, University of Pavia, via Ferrata 9, 27100, Pavia, Italy
| | - Barbara Mannucci
- Centro Grandi Strumenti, University of Pavia, Via Bassi 21, 27100, Pavia, Italy
| | - Maria Laura Mascotti
- Molecular Enzymology group, University of Groningen, Nijenborgh 4, 9747AG, Groningen, The Netherlands.
- IMIBIO-SL CONICET, Facultad de Química Bioquímica y Farmacia, Universidad Nacional de San Luis, San Luis, Argentina.
- Instituto de Histología y Embriología de Mendoza (IHEM)-CONICET-Universidad Nacional de Cuyo, 5500, Mendoza, Argentina.
| | - Marco W Fraaije
- Molecular Enzymology group, University of Groningen, Nijenborgh 4, 9747AG, Groningen, The Netherlands.
| | - Andrea Mattevi
- Department of Biology and Biotechnology, University of Pavia, via Ferrata 9, 27100, Pavia, Italy.
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20
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Pulsford SB, Outram MA, Förster B, Rhodes T, Williams SJ, Badger MR, Price GD, Jackson CJ, Long BM. Cyanobacterial α-carboxysome carbonic anhydrase is allosterically regulated by the Rubisco substrate RuBP. SCIENCE ADVANCES 2024; 10:eadk7283. [PMID: 38728392 PMCID: PMC11086599 DOI: 10.1126/sciadv.adk7283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 04/08/2024] [Indexed: 05/12/2024]
Abstract
Cyanobacterial CO2 concentrating mechanisms (CCMs) sequester a globally consequential proportion of carbon into the biosphere. Proteinaceous microcompartments, called carboxysomes, play a critical role in CCM function, housing two enzymes to enhance CO2 fixation: carbonic anhydrase (CA) and Rubisco. Despite its importance, our current understanding of the carboxysomal CAs found in α-cyanobacteria, CsoSCA, remains limited, particularly regarding the regulation of its activity. Here, we present a structural and biochemical study of CsoSCA from the cyanobacterium Cyanobium sp. PCC7001. Our results show that the Cyanobium CsoSCA is allosterically activated by the Rubisco substrate ribulose-1,5-bisphosphate and forms a hexameric trimer of dimers. Comprehensive phylogenetic and mutational analyses are consistent with this regulation appearing exclusively in cyanobacterial α-carboxysome CAs. These findings clarify the biologically relevant oligomeric state of α-carboxysomal CAs and advance our understanding of the regulation of photosynthesis in this globally dominant lineage.
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Affiliation(s)
- Sacha B. Pulsford
- ARC Centre of Excellence in Synthetic Biology, Sydney, NSW, Australia
- Research School of Chemistry, The Australian National University, Canberra, ACT 2601, Australia
| | - Megan A. Outram
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
| | - Britta Förster
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
| | - Timothy Rhodes
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
| | - Simon J. Williams
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
| | - Murray R. Badger
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
| | - G. Dean Price
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
| | - Colin J. Jackson
- ARC Centre of Excellence in Synthetic Biology, Sydney, NSW, Australia
- Research School of Chemistry, The Australian National University, Canberra, ACT 2601, Australia
| | - Benedict M. Long
- ARC Centre of Excellence in Synthetic Biology, Sydney, NSW, Australia
- School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW 2308, Australia
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21
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Korasick DA, Buckley DP, Palpacelli A, Cursio I, Cesaroni E, Cheng J, Tanner JJ. Biochemical, structural, and computational analyses of two new clinically identified missense mutations of ALDH7A1. Chem Biol Interact 2024; 394:110993. [PMID: 38604394 PMCID: PMC11073572 DOI: 10.1016/j.cbi.2024.110993] [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: 02/27/2024] [Revised: 03/30/2024] [Accepted: 04/04/2024] [Indexed: 04/13/2024]
Abstract
Aldehyde dehydrogenase 7A1 (ALDH7A1) catalyzes a step of lysine catabolism. Certain missense mutations in the ALDH7A1 gene cause pyridoxine dependent epilepsy (PDE), a rare autosomal neurometabolic disorder with recessive inheritance that affects almost 1:65,000 live births and is classically characterized by recurrent seizures from the neonatal period. We report a biochemical, structural, and computational study of two novel ALDH7A1 missense mutations that were identified in a child with rare recurrent seizures from the third month of life. The mutations affect two residues in the oligomer interfaces of ALDH7A1, Arg134 and Arg441 (Arg162 and Arg469 in the HGVS nomenclature). The corresponding enzyme variants R134S and R441C (p.Arg162Ser and p.Arg469Cys in the HGVS nomenclature) were expressed in Escherichia coli and purified. R134S and R441C have 10,000- and 50-fold lower catalytic efficiency than wild-type ALDH7A1, respectively. Sedimentation velocity analytical ultracentrifugation shows that R134S is defective in tetramerization, remaining locked in a dimeric state even in the presence of the tetramer-inducing coenzyme NAD+. Because the tetramer is the active form of ALDH7A1, the defect in oligomerization explains the very low catalytic activity of R134S. In contrast, R441C exhibits wild-type oligomerization behavior, and the 2.0 Å resolution crystal structure of R441C complexed with NAD+ revealed no obvious structural perturbations when compared to the wild-type enzyme structure. Molecular dynamics simulations suggest that the mutation of Arg441 to Cys may increase intersubunit ion pairs and alter the dynamics of the active site gate. Our biochemical, structural, and computational data on two novel clinical variants of ALDH7A1 add to the complexity of the molecular determinants underlying pyridoxine dependent epilepsy.
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Affiliation(s)
- David A Korasick
- Department of Biochemistry, University of Missouri, Columbia, MO, 65211, United States
| | - David P Buckley
- Department of Biochemistry, University of Missouri, Columbia, MO, 65211, United States
| | | | - Ida Cursio
- Child Neurology and Psychiatric Unit, Pediatric Hospital G. Salesi, United Hospitals of Marche, Ancona, Italy
| | - Elisabetta Cesaroni
- Child Neurology and Psychiatric Unit, Pediatric Hospital G. Salesi, United Hospitals of Marche, Ancona, Italy
| | - Jianlin Cheng
- Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, MO, 65211, United States
| | - John J Tanner
- Department of Biochemistry, University of Missouri, Columbia, MO, 65211, United States; Department of Chemistry, University of Missouri, Columbia, MO, 65211, United States.
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22
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Tran TTQ, Narayanan C, Loes AN, Click TH, Pham NTH, Létourneau M, Harms MJ, Calmettes C, Agarwal PK, Doucet N. Ancestral sequence reconstruction dissects structural and functional differences among eosinophil ribonucleases. J Biol Chem 2024; 300:107280. [PMID: 38588810 PMCID: PMC11101842 DOI: 10.1016/j.jbc.2024.107280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 03/30/2024] [Accepted: 04/03/2024] [Indexed: 04/10/2024] Open
Abstract
Evolutionarily conserved structural folds can give rise to diverse biological functions, yet predicting atomic-scale interactions that contribute to the emergence of novel activities within such folds remains challenging. Pancreatic-type ribonucleases illustrate this complexity, sharing a core structure that has evolved to accommodate varied functions. In this study, we used ancestral sequence reconstruction to probe evolutionary and molecular determinants that distinguish biological activities within eosinophil members of the RNase 2/3 subfamily. Our investigation unveils functional, structural, and dynamical behaviors that differentiate the evolved ancestral ribonuclease (AncRNase) from its contemporary eosinophil RNase orthologs. Leveraging the potential of ancestral reconstruction for protein engineering, we used AncRNase predictions to design a minimal 4-residue variant that transforms human RNase 2 into a chimeric enzyme endowed with the antimicrobial and cytotoxic activities of RNase 3 members. This work provides unique insights into mutational and evolutionary pathways governing structure, function, and conformational states within the eosinophil RNase subfamily, offering potential for targeted modulation of RNase-associated functions.
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Affiliation(s)
- Thi Thanh Quynh Tran
- Centre Armand-Frappier Santé Biotechnologie, Institut national de la recherche scientifique (INRS), Université du Québec, Laval, Quebec, Canada
| | - Chitra Narayanan
- Department of Chemistry, York College, City University of New York (CUNY), Jamaica, New York, USA
| | - Andrea N Loes
- Institute of Molecular Biology and Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon, USA
| | - Timothy H Click
- Chemistry and Biochemistry, University of Mary, Bismarck, North Dakota, USA
| | - N T Hang Pham
- Centre Armand-Frappier Santé Biotechnologie, Institut national de la recherche scientifique (INRS), Université du Québec, Laval, Quebec, Canada
| | - Myriam Létourneau
- Centre Armand-Frappier Santé Biotechnologie, Institut national de la recherche scientifique (INRS), Université du Québec, Laval, Quebec, Canada
| | - Michael J Harms
- Institute of Molecular Biology and Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon, USA
| | - Charles Calmettes
- Centre Armand-Frappier Santé Biotechnologie, Institut national de la recherche scientifique (INRS), Université du Québec, Laval, Quebec, Canada; PROTEO, The Quebec Network for Research on Protein Function, Engineering, and Applications, UQAM, Montréal, Quebec, Canada
| | - Pratul K Agarwal
- Department of Physiological Sciences and High-Performance Computing Center, Oklahoma State University, Stillwater, Oklahoma, USA
| | - Nicolas Doucet
- Centre Armand-Frappier Santé Biotechnologie, Institut national de la recherche scientifique (INRS), Université du Québec, Laval, Quebec, Canada; PROTEO, The Quebec Network for Research on Protein Function, Engineering, and Applications, UQAM, Montréal, Quebec, Canada.
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23
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Neumann P, Heidemann JL, Wollenhaupt J, Dickmanns A, Agthe M, Weiss MS, Ficner R. A small step towards an important goal: fragment screen of the c-di-AMP-synthesizing enzyme CdaA. Acta Crystallogr D Struct Biol 2024; 80:350-361. [PMID: 38682668 PMCID: PMC11066881 DOI: 10.1107/s205979832400336x] [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: 02/22/2024] [Accepted: 04/16/2024] [Indexed: 05/01/2024] Open
Abstract
CdaA is the most widespread diadenylate cyclase in many bacterial species, including several multidrug-resistant human pathogens. The enzymatic product of CdaA, cyclic di-AMP, is a secondary messenger that is essential for the viability of many bacteria. Its absence in humans makes CdaA a very promising and attractive target for the development of new antibiotics. Here, the structural results are presented of a crystallographic fragment screen against CdaA from Listeria monocytogenes, a saprophytic Gram-positive bacterium and an opportunistic food-borne pathogen that can cause listeriosis in humans and animals. Two of the eight fragment molecules reported here were localized in the highly conserved ATP-binding site. These fragments could serve as potential starting points for the development of antibiotics against several CdaA-dependent bacterial species.
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Affiliation(s)
- Piotr Neumann
- Department of Molecular Structural Biology, Institute of Microbiology and Genetics, GZMB, Georg-August-University Göttingen, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany
| | - Jana L. Heidemann
- Department of Molecular Structural Biology, Institute of Microbiology and Genetics, GZMB, Georg-August-University Göttingen, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany
| | - Jan Wollenhaupt
- Macromolecular Crystallography, Helmholtz-Zentrum Berlin, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - Achim Dickmanns
- Department of Molecular Structural Biology, Institute of Microbiology and Genetics, GZMB, Georg-August-University Göttingen, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany
| | - Michael Agthe
- Institut für Nanostruktur- und Festkörperphysik, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Manfred S. Weiss
- Macromolecular Crystallography, Helmholtz-Zentrum Berlin, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - Ralf Ficner
- Department of Molecular Structural Biology, Institute of Microbiology and Genetics, GZMB, Georg-August-University Göttingen, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany
- Cluster of Excellence ‘Multiscale Bioimaging: From Molecular Machines to Networks of Excitable Cells’ (MBExC), University of Göttingen, 37075 Göttingen, Germany
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24
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Sudol ASL, Crispin M, Tews I. The IgG-specific endoglycosidases EndoS and EndoS2 are distinguished by conformation and antibody recognition. J Biol Chem 2024; 300:107245. [PMID: 38569940 PMCID: PMC11063906 DOI: 10.1016/j.jbc.2024.107245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 03/19/2024] [Accepted: 03/25/2024] [Indexed: 04/05/2024] Open
Abstract
The IgG-specific endoglycosidases EndoS and EndoS2 from Streptococcus pyogenes can remove conserved N-linked glycans present on the Fc region of host antibodies to inhibit Fc-mediated effector functions. These enzymes are therefore being investigated as therapeutics for suppressing unwanted immune activation, and have additional application as tools for antibody glycan remodeling. EndoS and EndoS2 differ in Fc glycan substrate specificity due to structural differences within their catalytic glycosyl hydrolase domains. However, a chimeric EndoS enzyme with a substituted glycosyl hydrolase from EndoS2 loses catalytic activity, despite high structural homology between the two enzymes, indicating either mechanistic divergence of EndoS and EndoS2, or improperly-formed domain interfaces in the chimeric enzyme. Here, we present the crystal structure of the EndoS2-IgG1 Fc complex determined to 3.0 Å resolution. Comparison of complexed and unliganded EndoS2 reveals relative reorientation of the glycosyl hydrolase, leucine-rich repeat and hybrid immunoglobulin domains. The conformation of the complexed EndoS2 enzyme is also different when compared to the earlier EndoS-IgG1 Fc complex, and results in distinct contact surfaces between the two enzymes and their Fc substrate. These findings indicate mechanistic divergence of EndoS2 and EndoS. It will be important to consider these differences in the design of IgG-specific enzymes, developed to enable customizable antibody glycosylation.
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Affiliation(s)
- Abigail S L Sudol
- School of Biological Sciences, University of Southampton, Southampton, UK
| | - Max Crispin
- School of Biological Sciences, University of Southampton, Southampton, UK.
| | - Ivo Tews
- School of Biological Sciences, University of Southampton, Southampton, UK.
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25
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Brosey CA, Link TM, Shen R, Moiani D, Burnett K, Hura GL, Jones DE, Tainer JA. Chemical screening by time-resolved X-ray scattering to discover allosteric probes. Nat Chem Biol 2024:10.1038/s41589-024-01609-1. [PMID: 38671223 DOI: 10.1038/s41589-024-01609-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Accepted: 03/20/2024] [Indexed: 04/28/2024]
Abstract
Drug discovery relies on efficient identification of small-molecule leads and their interactions with macromolecular targets. However, understanding how chemotypes impact mechanistically important conformational states often remains secondary among high-throughput discovery methods. Here, we present a conformational discovery pipeline integrating time-resolved, high-throughput small-angle X-ray scattering (TR-HT-SAXS) and classic fragment screening applied to allosteric states of the mitochondrial import oxidoreductase apoptosis-inducing factor (AIF). By monitoring oxidized and X-ray-reduced AIF states, TR-HT-SAXS leverages structure and kinetics to generate a multidimensional screening dataset that identifies fragment chemotypes allosterically stimulating AIF dimerization. Fragment-induced dimerization rates, quantified with time-resolved SAXS similarity analysis (kVR), capture structure-activity relationships (SAR) across the top-ranked 4-aminoquinoline chemotype. Crystallized AIF-aminoquinoline complexes validate TR-SAXS-guided SAR, supporting this conformational chemotype for optimization. AIF-aminoquinoline structures and mutational analysis reveal active site F482 as an underappreciated allosteric stabilizer of AIF dimerization. This conformational discovery pipeline illustrates TR-HT-SAXS as an effective technology for targeting chemical leads to important macromolecular states.
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Affiliation(s)
- Chris A Brosey
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
| | - Todd M Link
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Runze Shen
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Davide Moiani
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Kathryn Burnett
- MBIB Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Greg L Hura
- MBIB Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, Santa Cruz, CA, USA
| | - Darin E Jones
- Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - John A Tainer
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
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26
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Grosjean N, Yee EF, Kumaran D, Chopra K, Abernathy M, Biswas S, Byrnes J, Kreitler DF, Cheng JF, Ghosh A, Almo SC, Iwai M, Niyogi KK, Pakrasi HB, Sarangi R, van Dam H, Yang L, Blaby IK, Blaby-Haas CE. A hemoprotein with a zinc-mirror heme site ties heme availability to carbon metabolism in cyanobacteria. Nat Commun 2024; 15:3167. [PMID: 38609367 PMCID: PMC11014987 DOI: 10.1038/s41467-024-47486-z] [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: 05/02/2023] [Accepted: 04/02/2024] [Indexed: 04/14/2024] Open
Abstract
Heme has a critical role in the chemical framework of the cell as an essential protein cofactor and signaling molecule that controls diverse processes and molecular interactions. Using a phylogenomics-based approach and complementary structural techniques, we identify a family of dimeric hemoproteins comprising a domain of unknown function DUF2470. The heme iron is axially coordinated by two zinc-bound histidine residues, forming a distinct two-fold symmetric zinc-histidine-iron-histidine-zinc site. Together with structure-guided in vitro and in vivo experiments, we further demonstrate the existence of a functional link between heme binding by Dri1 (Domain related to iron 1, formerly ssr1698) and post-translational regulation of succinate dehydrogenase in the cyanobacterium Synechocystis, suggesting an iron-dependent regulatory link between photosynthesis and respiration. Given the ubiquity of proteins containing homologous domains and connections to heme metabolism across eukaryotes and prokaryotes, we propose that DRI (Domain Related to Iron; formerly DUF2470) functions at the molecular level as a heme-dependent regulatory domain.
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Affiliation(s)
- Nicolas Grosjean
- Biology Department, Brookhaven National Laboratory, Upton, NY, USA
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Estella F Yee
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY, USA
| | - Desigan Kumaran
- Biology Department, Brookhaven National Laboratory, Upton, NY, USA
| | - Kriti Chopra
- Computational Science Initiative, Brookhaven National Laboratory, Upton, NY, USA
| | - Macon Abernathy
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Sandeep Biswas
- Department of Biology, Washington University, St. Louis, MO, USA
| | - James Byrnes
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY, USA
| | - Dale F Kreitler
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY, USA
| | - Jan-Fang Cheng
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Agnidipta Ghosh
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Steven C Almo
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Masakazu Iwai
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Krishna K Niyogi
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Howard Hughes Medical Institute, University of California, Berkeley, CA, USA
| | | | - Ritimukta Sarangi
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Hubertus van Dam
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | - Lin Yang
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY, USA
| | - Ian K Blaby
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Crysten E Blaby-Haas
- Biology Department, Brookhaven National Laboratory, Upton, NY, USA.
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
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27
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Rosenberg EM, Jian X, Soubias O, Jackson RA, Gladu E, Andersen E, Esser L, Sodt AJ, Xia D, Byrd RA, Randazzo PA. Point mutations in Arf1 reveal cooperative effects of the N-terminal extension and myristate for GTPase-activating protein catalytic activity. PLoS One 2024; 19:e0295103. [PMID: 38574162 PMCID: PMC10994351 DOI: 10.1371/journal.pone.0295103] [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: 11/13/2023] [Accepted: 03/05/2024] [Indexed: 04/06/2024] Open
Abstract
The ADP-ribosylation factors (Arfs) constitute a family of small GTPases within the Ras superfamily, with a distinguishing structural feature of a hypervariable N-terminal extension of the G domain modified with myristate. Arf proteins, including Arf1, have roles in membrane trafficking and cytoskeletal dynamics. While screening for Arf1:small molecule co-crystals, we serendipitously solved the crystal structure of the non-myristoylated engineered mutation [L8K]Arf1 in complex with a GDP analogue. Like wild-type (WT) non-myristoylated Arf1•GDP, we observed that [L8K]Arf1 exhibited an N-terminal helix that occludes the hydrophobic cavity that is occupied by the myristoyl group in the GDP-bound state of the native protein. However, the helices were offset from one another due to the L8K mutation, with a significant change in position of the hinge region connecting the N-terminus to the G domain. Hypothesizing that the observed effects on behavior of the N-terminus affects interaction with regulatory proteins, we mutated two hydrophobic residues to examine the role of the N-terminal extension for interaction with guanine nucleotide exchange factors (GEFs) and GTPase Activating Proteins (GAPs. Different than previous studies, all mutations were examined in the context of myristoylated Arf. Mutations had little or no effect on spontaneous or GEF-catalyzed guanine nucleotide exchange but did affect interaction with GAPs. [F13A]myrArf1 was less than 1/2500, 1/1500, and 1/200 efficient as substrate for the GAPs ASAP1, ARAP1 and AGAP1; however, [L8A/F13A]myrArf1 was similar to WT myrArf1. Using molecular dynamics simulations, the effect of the mutations on forming alpha helices adjacent to a membrane surface was examined, yet no differences were detected. The results indicate that lipid modifications of GTPases and consequent anchoring to a membrane influences protein function beyond simple membrane localization. Hypothetical mechanisms are discussed.
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Affiliation(s)
- Eric M. Rosenberg
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, United States of America
| | - Xiaoying Jian
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, United States of America
| | - Olivier Soubias
- Section of Macromolecular NMR, Center for Structural Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD, United States of America
| | - Rebekah A. Jackson
- Section of Macromolecular NMR, Center for Structural Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD, United States of America
| | - Erin Gladu
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, United States of America
| | - Emily Andersen
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, United States of America
| | - Lothar Esser
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland, United States of America
| | - Alexander J. Sodt
- Unit of Membrane Chemical Physics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD, United States of America
| | - Di Xia
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland, United States of America
| | - R. Andrew Byrd
- Section of Macromolecular NMR, Center for Structural Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD, United States of America
| | - Paul A. Randazzo
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, United States of America
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28
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Zhou J, Chen Q, Ren R, Yang J, Liu B, Horton JR, Chang C, Li C, Maksoud L, Yang Y, Rotili D, Zhang X, Blumenthal RM, Chen T, Gao Y, Valente S, Mai A, Cheng X. Quinoline-based compounds can inhibit diverse enzymes that act on DNA. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.03.587980. [PMID: 38617249 PMCID: PMC11014617 DOI: 10.1101/2024.04.03.587980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
DNA methylation, as exemplified by cytosine-C5 methylation in mammals and adenine-N6 methylation in bacteria, is a crucial epigenetic mechanism driving numerous vital biological processes. Developing non-nucleoside inhibitors to cause DNA hypomethylation is a high priority, in order to treat a variety of significant medical conditions without the toxicities associated with existing cytidine-based hypomethylating agents. In this study, we have characterized fifteen quinoline-based analogs. Notably, compounds with additions like a methylamine ( 9 ) or methylpiperazine ( 11 ) demonstrate similar low micromolar inhibitory potency against both human DNMT1 (which generates C5-methylcytosine) and Clostridioides difficile CamA (which generates N6-methyladenine). Structurally, compounds 9 and 11 specifically intercalate into CamA-bound DNA via the minor groove, adjacent to the target adenine, leading to a substantial conformational shift that moves the catalytic domain away from the DNA. This study adds to the limited examples of DNA methyltransferases being inhibited by non-nucleotide compounds through DNA intercalation, following the discovery of dicyanopyridine-based inhibitors for DNMT1. Furthermore, our study shows that some of these quinoline-based analogs inhibit other enzymes that act on DNA, such as polymerases and base excision repair glycosylases. Finally, in cancer cells compound 11 elicits DNA damage response via p53 activation. Abstract Figure Highlights Six of fifteen quinoline-based derivatives demonstrated comparable low micromolar inhibitory effects on human cytosine methyltransferase DNMT1, and the bacterial adenine methyltransferases Clostridioides difficile CamA and Caulobacter crescentus CcrM. Compounds 9 and 11 were found to intercalate into a DNA substrate bound by CamA. These quinoline-based derivatives also showed inhibitory activity against various base excision repair DNA glycosylases, and DNA and RNA polymerases. Compound 11 provokes DNA damage response via p53 activation in cancer cells.
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29
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Mydy LS, Hungerford J, Chigumba DN, Konwerski JR, Jantzi SC, Wang D, Smith JL, Kersten RD. An intramolecular macrocyclase in plant ribosomal peptide biosynthesis. Nat Chem Biol 2024; 20:530-540. [PMID: 38355722 PMCID: PMC11049724 DOI: 10.1038/s41589-024-01552-1] [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: 09/06/2023] [Accepted: 01/12/2024] [Indexed: 02/16/2024]
Abstract
The biosynthetic dogma of ribosomally synthesized and posttranslationally modified peptides (RiPP) involves enzymatic intermolecular modification of core peptide motifs in precursor peptides. The plant-specific BURP-domain protein family, named after their four founding members, includes autocatalytic peptide cyclases involved in the biosynthesis of side-chain-macrocyclic plant RiPPs. Here we show that AhyBURP, a representative of the founding Unknown Seed Protein-type BURP-domain subfamily, catalyzes intramolecular macrocyclizations of its core peptide during the sequential biosynthesis of monocyclic lyciumin I via glycine-tryptophan crosslinking and bicyclic legumenin via glutamine-tyrosine crosslinking. X-ray crystallography of AhyBURP reveals the BURP-domain fold with two type II copper centers derived from a conserved stapled-disulfide and His motif. We show the macrocyclization of lyciumin-C(sp3)-N-bond formation followed by legumenin-C(sp3)-O-bond formation requires dioxygen and radical involvement based on enzyme assays in anoxic conditions and isotopic labeling. Our study expands enzymatic intramolecular modifications beyond catalytic moiety and chromophore biogenesis to RiPP biosynthesis.
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Affiliation(s)
- Lisa S Mydy
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI, USA.
| | - Jordan Hungerford
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Desnor N Chigumba
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI, USA
| | | | - Sarah C Jantzi
- Plasma Chemistry Laboratory, Center for Applied Isotope Studies, University of Georgia, Athens, GA, USA
| | - Di Wang
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Janet L Smith
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Roland D Kersten
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI, USA.
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30
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Benson DR, Deng B, Kashipathy MM, Lovell S, Battaile KP, Cooper A, Gao P, Fenton AW, Zhu H. The N-terminal intrinsically disordered region of Ncb5or docks with the cytochrome b 5 core to form a helical motif that is of ancient origin. Proteins 2024; 92:554-566. [PMID: 38041394 DOI: 10.1002/prot.26647] [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: 07/21/2023] [Revised: 11/10/2023] [Accepted: 11/17/2023] [Indexed: 12/03/2023]
Abstract
NADH cytochrome b5 oxidoreductase (Ncb5or) is a cytosolic ferric reductase implicated in diabetes and neurological conditions. Ncb5or comprises cytochrome b5 (b5 ) and cytochrome b5 reductase (b5 R) domains separated by a CHORD-Sgt1 (CS) linker domain. Ncb5or redox activity depends on proper inter-domain interactions to mediate electron transfer from NADH or NADPH via FAD to heme. While full-length human Ncb5or has proven resistant to crystallization, we have succeeded in obtaining high-resolution atomic structures of the b5 domain and a construct containing the CS and b5 R domains (CS/b5 R). Ncb5or also contains an N-terminal intrinsically disordered region of 50 residues that has no homologs in other protein families in animals but features a distinctive, conserved L34 MDWIRL40 motif also present in reduced lateral root formation (RLF) protein in rice and increased recombination center 21 in baker's yeast, all attaching to a b5 domain. After unsuccessful attempts at crystallizing a human Ncb5or construct comprising the N-terminal region naturally fused to the b5 domain, we were able to obtain a high-resolution atomic structure of a recombinant rice RLF construct corresponding to residues 25-129 of human Ncb5or (52% sequence identity; 74% similarity). The structure reveals Trp120 (corresponding to invariant Trp37 in Ncb5or) to be part of an 11-residue α-helix (S116 QMDWLKLTRT126 ) packing against two of the four helices in the b5 domain that surround heme (α2 and α5). The Trp120 side chain forms a network of interactions with the side chains of four highly conserved residues corresponding to Tyr85 and Tyr88 (α2), Cys124 (α5), and Leu47 in Ncb5or. Circular dichroism measurements of human Ncb5or fragments further support a key role of Trp37 in nucleating the formation of the N-terminal helix, whose location in the N/b5 module suggests a role in regulating the function of this multi-domain redox enzyme. This study revealed for the first time an ancient origin of a helical motif in the N/b5 module as reflected by its existence in a class of cytochrome b5 proteins from three kingdoms among eukaryotes.
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Affiliation(s)
- David R Benson
- Department of Chemistry, University of Kansas, Lawrence, Kansas, USA
| | - Bin Deng
- Department of Physical Therapy and Rehabilitation Science, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Maithri M Kashipathy
- Protein Structure and X-ray Crystallography Laboratory, The University of Kansas, Lawrence, Kansas, USA
| | - Scott Lovell
- Protein Structure and X-ray Crystallography Laboratory, The University of Kansas, Lawrence, Kansas, USA
| | | | - Anne Cooper
- Protein Production Group, The University of Kansas, Lawrence, Kansas, USA
| | - Philip Gao
- Protein Production Group, The University of Kansas, Lawrence, Kansas, USA
| | - Aron W Fenton
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Hao Zhu
- Department of Physical Therapy and Rehabilitation Science, University of Kansas Medical Center, Kansas City, Kansas, USA
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, Kansas, USA
- Department of Clinical Laboratory Sciences, University of Kansas Medical Center, Kansas City, Kansas, USA
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31
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Koeppl LH, Popadić D, Saleem-Batcha R, Germer P, Andexer JN. Structure, function and substrate preferences of archaeal S-adenosyl-L-homocysteine hydrolases. Commun Biol 2024; 7:380. [PMID: 38548921 PMCID: PMC10978960 DOI: 10.1038/s42003-024-06078-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 03/20/2024] [Indexed: 04/01/2024] Open
Abstract
S-Adenosyl-L-homocysteine hydrolase (SAHH) reversibly cleaves S-adenosyl-L-homocysteine, the product of S-adenosyl-L-methionine-dependent methylation reactions. The conversion of S-adenosyl-L-homocysteine into adenosine and L-homocysteine plays an important role in the regulation of the methyl cycle. An alternative metabolic route for S-adenosyl-L-methionine regeneration in the extremophiles Methanocaldococcus jannaschii and Thermotoga maritima has been identified, featuring the deamination of S-adenosyl-L-homocysteine to S-inosyl-L-homocysteine. Herein, we report the structural characterisation of different archaeal SAHHs together with a biochemical analysis of various SAHHs from all three domains of life. Homologues deriving from the Euryarchaeota phylum show a higher conversion rate with S-inosyl-L-homocysteine compared to S-adenosyl-L-homocysteine. Crystal structures of SAHH originating from Pyrococcus furiosus in complex with SLH and inosine as ligands, show architectural flexibility in the active site and offer deeper insights into the binding mode of hypoxanthine-containing substrates. Altogether, the findings of our study support the understanding of an alternative metabolic route for S-adenosyl-L-methionine and offer insights into the evolutionary progression and diversification of SAHHs involved in methyl and purine salvage pathways.
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Affiliation(s)
- Lars-Hendrik Koeppl
- Institute of Pharmaceutical Sciences, University of Freiburg, Albertstr. 25, 79104, Freiburg, Germany
| | - Désirée Popadić
- Institute of Pharmaceutical Sciences, University of Freiburg, Albertstr. 25, 79104, Freiburg, Germany
| | - Raspudin Saleem-Batcha
- Institute of Pharmaceutical Sciences, University of Freiburg, Albertstr. 25, 79104, Freiburg, Germany
| | - Philipp Germer
- Institute of Pharmaceutical Sciences, University of Freiburg, Albertstr. 25, 79104, Freiburg, Germany
| | - Jennifer N Andexer
- Institute of Pharmaceutical Sciences, University of Freiburg, Albertstr. 25, 79104, Freiburg, Germany.
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32
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Tan B, Zhang X, Ansari A, Jadhav P, Tan H, Li K, Chopra A, Ford A, Chi X, Ruiz FX, Arnold E, Deng X, Wang J. Design of a SARS-CoV-2 papain-like protease inhibitor with antiviral efficacy in a mouse model. Science 2024; 383:1434-1440. [PMID: 38547259 DOI: 10.1126/science.adm9724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 02/22/2024] [Indexed: 04/02/2024]
Abstract
The emergence of SARS-CoV-2 variants and drug-resistant mutants calls for additional oral antivirals. The SARS-CoV-2 papain-like protease (PLpro) is a promising but challenging drug target. We designed and synthesized 85 noncovalent PLpro inhibitors that bind to a recently discovered ubiquitin binding site and the known BL2 groove pocket near the S4 subsite. Leads inhibited PLpro with the inhibitory constant Ki values from 13.2 to 88.2 nanomolar. The co-crystal structures of PLpro with eight leads revealed their interaction modes. The in vivo lead Jun12682 inhibited SARS-CoV-2 and its variants, including nirmatrelvir-resistant strains with EC50 from 0.44 to 2.02 micromolar. Oral treatment with Jun12682 improved survival and reduced lung viral loads and lesions in a SARS-CoV-2 infection mouse model, suggesting that PLpro inhibitors are promising oral SARS-CoV-2 antiviral candidates.
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Affiliation(s)
- Bin Tan
- Department of Medicinal Chemistry, Ernest Mario School of Pharmacy, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA
| | - Xiaoming Zhang
- Department Physiological Sciences, College of Veterinary Medicine, Oklahoma State University, Stillwater, OK 74078, USA
| | - Ahmadullah Ansari
- Center for Advanced Biotechnology and Medicine, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA
- Department of Chemistry and Chemical Biology, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA
| | - Prakash Jadhav
- Department of Medicinal Chemistry, Ernest Mario School of Pharmacy, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA
| | - Haozhou Tan
- Department of Medicinal Chemistry, Ernest Mario School of Pharmacy, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA
| | - Kan Li
- Department of Medicinal Chemistry, Ernest Mario School of Pharmacy, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA
| | - Ashima Chopra
- Center for Advanced Biotechnology and Medicine, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA
- Department of Chemistry and Chemical Biology, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA
| | - Alexandra Ford
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Oklahoma State University, Stillwater, OK 74078, USA
| | - Xiang Chi
- Department Physiological Sciences, College of Veterinary Medicine, Oklahoma State University, Stillwater, OK 74078, USA
| | - Francesc Xavier Ruiz
- Center for Advanced Biotechnology and Medicine, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA
- Department of Chemistry and Chemical Biology, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA
| | - Eddy Arnold
- Center for Advanced Biotechnology and Medicine, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA
- Department of Chemistry and Chemical Biology, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA
| | - Xufang Deng
- Department Physiological Sciences, College of Veterinary Medicine, Oklahoma State University, Stillwater, OK 74078, USA
- Oklahoma Center for Respiratory and Infectious Diseases, Oklahoma State University, Stillwater, OK 74078, USA
| | - Jun Wang
- Department of Medicinal Chemistry, Ernest Mario School of Pharmacy, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA
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Nagy GN, Zhao XF, Karlsson R, Wang K, Duman R, Harlos K, El Omari K, Wagner A, Clausen H, Miller RL, Giger RJ, Jones EY. Structure and function of Semaphorin-5A glycosaminoglycan interactions. Nat Commun 2024; 15:2723. [PMID: 38548715 PMCID: PMC10978931 DOI: 10.1038/s41467-024-46725-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Accepted: 03/07/2024] [Indexed: 04/01/2024] Open
Abstract
Integration of extracellular signals by neurons is pivotal for brain development, plasticity, and repair. Axon guidance relies on receptor-ligand interactions crosstalking with extracellular matrix components. Semaphorin-5A (Sema5A) is a bifunctional guidance cue exerting attractive and inhibitory effects on neuronal growth through the interaction with heparan sulfate (HS) and chondroitin sulfate (CS) glycosaminoglycans (GAGs), respectively. Sema5A harbors seven thrombospondin type-1 repeats (TSR1-7) important for GAG binding, however the underlying molecular basis and functions in vivo remain enigmatic. Here we dissect the structural basis for Sema5A:GAG specificity and demonstrate the functional significance of this interaction in vivo. Using x-ray crystallography, we reveal a dimeric fold variation for TSR4 that accommodates GAG interactions. TSR4 co-crystal structures identify binding residues validated by site-directed mutagenesis. In vitro and cell-based assays uncover specific GAG epitopes necessary for TSR association. We demonstrate that HS-GAG binding is preferred over CS-GAG and mediates Sema5A oligomerization. In vivo, Sema5A:GAG interactions are necessary for Sema5A function and regulate Plexin-A2 dependent dentate progenitor cell migration. Our study rationalizes Sema5A associated developmental and neurological disorders and provides mechanistic insights into how multifaceted guidance functions of a single transmembrane cue are regulated by proteoglycans.
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Affiliation(s)
- Gergely N Nagy
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK.
- Department of Applied Biotechnology and Food Science, Faculty of Chemical Technology and Biotechnology, Budapest University of Technology and Economics, Budapest, Hungary.
- Institute of Molecular Life Sciences, HUN-REN Research Centre for Natural Sciences, Budapest, Hungary.
| | - Xiao-Feng Zhao
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Richard Karlsson
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen-N, Denmark
| | - Karen Wang
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Ramona Duman
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, UK
| | - Karl Harlos
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Kamel El Omari
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, UK
| | - Armin Wagner
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, UK
| | - Henrik Clausen
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen-N, Denmark
| | - Rebecca L Miller
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen-N, Denmark.
| | - Roman J Giger
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA.
- Department of Neurology, Ann Arbor, MI, USA.
| | - E Yvonne Jones
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK.
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34
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Meeks KR, Ji J, Protopopov MV, Tarkhanova OO, Moroz YS, Tanner JJ. Novel Fragment Inhibitors of PYCR1 from Docking-Guided X-ray Crystallography. J Chem Inf Model 2024; 64:1704-1718. [PMID: 38411104 PMCID: PMC11058006 DOI: 10.1021/acs.jcim.3c01879] [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: 02/28/2024]
Abstract
The proline biosynthetic enzyme Δ1-pyrroline-5-carboxylate (P5C) reductase 1 (PYCR1) is one of the most consistently upregulated enzymes across multiple cancer types and central to the metabolic rewiring of cancer cells. Herein, we describe a fragment-based, structure-first approach to the discovery of PYCR1 inhibitors. Thirty-seven fragment-like carboxylic acids in the molecular weight range of 143-289 Da were selected from docking and then screened using X-ray crystallography as the primary assay. Strong electron density was observed for eight compounds, corresponding to a crystallographic hit rate of 22%. The fragments are novel compared to existing proline analog inhibitors in that they block both the P5C substrate pocket and the NAD(P)H binding site. Four hits showed inhibition of PYCR1 in kinetic assays, and one has lower apparent IC50 than the current best proline analog inhibitor. These results show proof-of-concept for our inhibitor discovery approach and provide a basis for fragment-to-lead optimization.
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Affiliation(s)
- Kaylen R Meeks
- Department of Biochemistry, University of Missouri, Columbia, Missouri 65211, United States
| | - Juan Ji
- Department of Biochemistry, University of Missouri, Columbia, Missouri 65211, United States
| | | | - Olga O Tarkhanova
- Chemspace LLC, 85 Chervonotkatska Street, Suite 1, Kyïv 02094, Ukraine
| | - Yurii S Moroz
- Chemspace LLC, 85 Chervonotkatska Street, Suite 1, Kyïv 02094, Ukraine
- Department of Chemistry, Taras Shevchenko National University of Kyïv, Kyïv 01601, Ukraine
| | - John J Tanner
- Department of Biochemistry, University of Missouri, Columbia, Missouri 65211, United States
- Department of Chemistry, University of Missouri, Columbia, Missouri 65211, United States
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35
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Unni S, Kommu P, Aouti S, Nalli Y, Bharath MMS, Ali A, Padmanabhan B. Structural insights into the modulation Of SOD1 aggregation By a fungal metabolite Phialomustin-B: Therapeutic potential in ALS. PLoS One 2024; 19:e0298196. [PMID: 38446760 PMCID: PMC10917278 DOI: 10.1371/journal.pone.0298196] [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: 07/18/2023] [Accepted: 01/19/2024] [Indexed: 03/08/2024] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal human motor neuron disease leading to muscle atrophy and paralysis. Mutations in superoxide dismutase 1 (SOD1) are associated with familial ALS (fALS). The SOD1 mutants in ALS have a toxic-gain of function by destabilizing the functional SOD1 homodimer, consequently inducing fibril-like aggregation with a cytotoxic non-native trimer intermediate. Therefore, reducing SOD1 oligomerization via chemical modulators is an optimal therapy in ALS. Here, we report the discovery of Phialomustin-B, an unsaturated secondary metabolite from the endophytic fungus Phialophora mustea, as a modulator of SOD1 aggregation. The crystal structure of the SOD1-Phialomustin complex refined to 1.90 Å resolution demonstrated for the first time that the ligand binds to the dimer interface and the lateral region near the electrostatic loop. The aggregation analyses of SOD1WT and the disease mutant SOD1A4V revealed that Phialomustin-B reduces cytotoxic trimerization. We propose that Phialomustin-B is a potent lead molecule with therapeutic potential in fALS.
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Affiliation(s)
- Sruthi Unni
- Department of Biophysics, National Institute of Mental Health and Neurosciences, Bengaluru, India
| | - Padmini Kommu
- Department of Biophysics, National Institute of Mental Health and Neurosciences, Bengaluru, India
| | - Snehal Aouti
- Department of Biophysics, National Institute of Mental Health and Neurosciences, Bengaluru, India
| | - Yedukondalu Nalli
- CSIR-Indian Institute of Integrative Medicine, Natural Product Division, Jammu, India
| | - M. M. Srinivas Bharath
- Department of Clinical Psychopharmacology and Neurotoxicology, National Institute of Mental Health and Neurosciences, Bengaluru, India
| | - Asif Ali
- CSIR-Indian Institute of Integrative Medicine, Natural Product Division, Jammu, India
- Medicinal & Process Chemistry Division, CSIR-Central Drug Research Institute, Jankipuram Extension, Lucknow, India
| | - Balasundaram Padmanabhan
- Department of Biophysics, National Institute of Mental Health and Neurosciences, Bengaluru, India
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36
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Ibrahim M, Sun X, de Oliveira VM, Liu R, Clayton J, Kilani HE, Shen J, Hilgenfeld R. Why is the Omicron main protease of SARS-CoV-2 less stable than its wild-type counterpart? A crystallographic, biophysical, and theoretical study of the free enzyme and its complex with inhibitor 13b-K. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.04.583178. [PMID: 38496596 PMCID: PMC10942327 DOI: 10.1101/2024.03.04.583178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
During the continuing evolution of SARS-CoV-2, the Omicron variant of concern emerged in the second half of 2021 and has been dominant since November that year. Along with its sublineages, it has maintained a prominent role ever since. The Nsp5 main protease (Mpro) of the Omicron virus is characterized by a single dominant mutation, P132H. Here we determined the X-ray crystal structures of the P132H mutant (or O-Mpro) as free enzyme and in complex with the Mpro inhibitor, the alpha-ketoamide 13b-K, and we conducted enzymology, biophysical as well as theoretical studies to characterize the O-Mpro. We found that O-Mpro has a similar overall structure and binding with 13b-K; however, it displays lower enzymatic activity and lower thermal stability compared to the WT-Mpro (with "WT" referring to the original Wuhan-1 strain). Intriguingly, the imidazole ring of His132 and the carboxylate plane of Glu240 are in a stacked configuration in the X-ray structures determined here. The empirical folding free energy calculations suggest that the O-Mpro dimer is destabilized relative to the WT-Mpro due to the less favorable van der Waals interactions and backbone conformation in the individual protomers. The all-atom continuous constant pH molecular dynamics (MD) simulations reveal that His132 and Glu240 display coupled titration. At pH 7, His132 is predominantly neutral and in a stacked configuration with respect to Glu240 which is charged. In order to examine whether the Omicron mutation eases the emergence of further Mpro mutations, we also determined crystal structures of the relatively frequent P132H+T169S double mutant but found little evidence for a correlation between the two sites.
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Affiliation(s)
- Mohamed Ibrahim
- Institute of Molecular Medicine, University of Lübeck, 23562 Lübeck, Germany
| | - Xinyuanyuan Sun
- Institute of Molecular Medicine, University of Lübeck, 23562 Lübeck, Germany
| | - Vinicius Martins de Oliveira
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland 21201, USA
| | - Ruibin Liu
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland 21201, USA
| | - Joseph Clayton
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland 21201, USA
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, United States Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Haifa El Kilani
- Institute of Molecular Medicine, University of Lübeck, 23562 Lübeck, Germany
| | - Jana Shen
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland 21201, USA
| | - Rolf Hilgenfeld
- Institute of Molecular Medicine, University of Lübeck, 23562 Lübeck, Germany
- German Center for Infection Research (DZIF), Hamburg - Lübeck - Borstel - Riems Site, University of Lübeck, 23562 Lübeck, Germany
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37
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Afonine PV, Adams PD, Sobolev OV, Urzhumtsev AG. Accounting for nonuniformity of bulk-solvent: A mosaic model. Protein Sci 2024; 33:e4909. [PMID: 38358136 PMCID: PMC10868464 DOI: 10.1002/pro.4909] [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: 07/28/2023] [Revised: 12/08/2023] [Accepted: 01/08/2024] [Indexed: 02/16/2024]
Abstract
A flat mask-based model is almost universally used in macromolecular crystallography to account for disordered (bulk) solvent. This model assumes any voxel of the crystal unit cell that is not occupied by the atomic model is occupied by the solvent. The properties of this solvent are assumed to be exactly the same across the whole volume of the unit cell. While this is a reasonable approximation in practice, there are a number of scenarios where this model becomes suboptimal. In this work, we enumerate several of these scenarios and describe a new generalized approach to modeling the bulk-solvent which we refer to as mosaic bulk-solvent model. The mosaic bulk-solvent model allows nonuniform features of the solvent in the crystal to be accounted for in a computationally efficient way. It is implemented in the computational crystallography toolbox and the Phenix software.
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Affiliation(s)
- Pavel V. Afonine
- Molecular Biophysics & Integrated Bioimaging DivisionLawrence Berkeley National LaboratoryBerkeleyCaliforniaUSA
| | - Paul D. Adams
- Molecular Biophysics & Integrated Bioimaging DivisionLawrence Berkeley National LaboratoryBerkeleyCaliforniaUSA
- Department of BioengineeringUniversity of California BerkeleyBerkeleyCaliforniaUSA
| | - Oleg V. Sobolev
- Molecular Biophysics & Integrated Bioimaging DivisionLawrence Berkeley National LaboratoryBerkeleyCaliforniaUSA
| | - Alexandre G. Urzhumtsev
- Centre for Integrative BiologyInstitut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS–INSERM‐UdSIllkirchFrance
- Université de Lorraine, Faculté des Sciences et TechnologiesVandoeuvre‐les‐NancyFrance
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38
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Nitin K, Rajakumara E. Proxy-approach in understanding the bisubstrate activity of strictosidine synthases. Int J Biol Macromol 2024; 262:130091. [PMID: 38354931 DOI: 10.1016/j.ijbiomac.2024.130091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 01/20/2024] [Accepted: 02/08/2024] [Indexed: 02/16/2024]
Abstract
Besides tryptamine (1) and secologanin (2), non-cognate substrates also undergo a Pictet-Spengler reaction (PSR) catalyzed by strictosidine synthases (STR) with differing catalytic properties. We characterized the bisubstrate binding aspect of catalysis - order, affinity, and cooperativity - with STR orthologs from Rauvolfia serpentina (RsSTR) and Ophiorrhiza pumila (OpSTR) by an isothermal titration calorimetry (ITC) based 'proxy approach' that employed a non-reactive tryptamine analog (m1) to capture its inert ternary complexes with STRs and (2). ITC studies with OpSTR and (2) revealed 'tryptamine-first' cooperative binding with (1) and a simultaneous cooperative binding with (m1). Binding cooperativity among (m1) and (2) towards OpSTR was higher than RsSTR. Crystallographic study of RsSTR-(m1) complex helped to understand the unreactive binding of (m1) in terms of orientation and interactions in the RsSTR pocket. PSR with (m1) was revealed to be energetically unfeasible by the density functional theory (DFT) scans of the first hydrogen abstraction by RsSTR. The effect of pH on the bisubstrate binding to OpSTR was deciphered by molecular dynamics simulations (MDS), which also provided a molecular basis for the stability of complex of OpSTR with (m1) and (2). Therefore, we investigated STRs from a substrate binding perspective to inform drug-design and rational enzyme engineering efforts.
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Affiliation(s)
- Kulhar Nitin
- Macromolecular Structural Biology Laboratory, Department of Biotechnology, Indian Institute of Technology Hyderabad (IITH), Kandi, Sangareddy 502284, Telangana, India.
| | - Eerappa Rajakumara
- Macromolecular Structural Biology Laboratory, Department of Biotechnology, Indian Institute of Technology Hyderabad (IITH), Kandi, Sangareddy 502284, Telangana, India.
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Salvador GHM, Fernandes CAH, Borges RJ, Soares AM, Fontes MRM. Structural studies with crotoxin B from Crotalus durissus collilineatus venom suggest a heterodimeric assembly formed by two new isoforms. Biochimie 2024; 218:46-56. [PMID: 37659716 DOI: 10.1016/j.biochi.2023.08.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 08/07/2023] [Accepted: 08/31/2023] [Indexed: 09/04/2023]
Abstract
In accidents involving Crotalus snakes, the crotoxin complex (CTX) plays lethal action due to its neurotoxic activity. On the other hand, CTX have potential biotechnological application due to its anti-tumoral, anti-inflammatory, antimicrobial, analgesic and immunomodulatory properties. CTX is a heterodimer composed of Crotoxin A (CA or crotapotin), the acidic nontoxic and non-enzymatic component and; Crotoxin B (CB), a basic, toxic and catalytic PLA2. Currently, there are two classes of CTX isoforms, whose differences in their biological activities have been attributed to features presented in CB isoforms. Here, we present the crystal structure of CB isolated from the Crotalus durissus collilineatus venom. It amino acid sequence was assigned using the SEQUENCE SLIDER software, which revealed that the crystal structure is a heterodimer composed of two new CB isoforms (colCB-A and colCB-B). Bioinformatic and biophysical analyses showed that the toxin forms a tetrameric assembly in solution similar to CB from Crotalus durissus terrificus venom, despite some differences observed at the dimeric interface. By the previously proposed classification, the colCB-B presents features of the class I isoforms while colCB-A cannot be classified into classes I and II based on its amino acid sequence. Due to similar features observed for other CB isoforms found in the NCBI database and the results obtained for colCB-A, we suggest that there are more than two classes of CTX and CB isoforms in crotalic venoms.
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Affiliation(s)
- Guilherme H M Salvador
- Departamento de Biofísica e Farmacologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, SP, Brazil
| | - Carlos A H Fernandes
- Departamento de Biofísica e Farmacologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, SP, Brazil; UMR 7590, CNRS, Muséum National d'Histoire Naturelle, IRD, Institut de Minéralogie, Physique des Matériaux et de Cosmochimie (IMPMC), Sorbonne Université, Paris, France
| | - Rafael J Borges
- Departamento de Biofísica e Farmacologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, SP, Brazil; Centro de Química Medicina (CQMED), Centro de Biologia Molecular e Engenharia Genética (CBMEG), Universidade de Estadual de Campinas (UNICAMP), Campinas, SP, Brazil
| | - Andreimar M Soares
- Laboratório de Biotecnologia de Proteínas e Compostos Bioativos Aplicados, Fundação Oswaldo Cruz (FIOCRUZ), Unidade Rondônia, Porto Velho, RO, Brazil; Inst Nac. de Epidemiologia da Amazônia Ocidental (INCT-EPIAMO), Rede de Pesquisa e Conhecimento de Excelência na Amazônia Ocidental (RED-CONEXAO), Brazil
| | - Marcos R M Fontes
- Departamento de Biofísica e Farmacologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, SP, Brazil; Instituto de Estudos Avançados do Mar (IEAMar), Universidade Estadual Paulista (UNESP), São Vicente, SP, Brazil.
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Shi X, Dai Y, Lan Z, Wang S, Cui L, Xiao C, Zhao K, Li X, Liu W, Zhang Q. Interplay between the β-lactam side chain and an active-site mobile loop of NDM-1 in penicillin hydrolysis as a potential target for mechanism-based inhibitor design. Int J Biol Macromol 2024; 262:130041. [PMID: 38336327 DOI: 10.1016/j.ijbiomac.2024.130041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 02/04/2024] [Accepted: 02/06/2024] [Indexed: 02/12/2024]
Abstract
Metallo-β-lactamases (MβLs) stand as significant resistant mechanism against β-lactam antibiotics in Gram-negative bacteria. The worldwide dissemination of New Delhi metallo-β-lactamases (NDMs) intensifies antimicrobial resistance, posing severe threats to human health due to the absence of inhibitors available in clinical therapy. L3, a flexible β-hairpin loop flanking the active site in MβLs, has been proven to wield influence over the reaction process by assuming a crucial role in substrate recognition and intermediate stabilization. In principle, it potentially retards product release from the enzyme, consequently reducing the overall turnover rate although the details regarding this aspect remain inadequately elucidated. In this study, we crystallized NDM-1 in complex with three penicillin substrates, conducted molecular dynamics simulations, and measured the steady-state kinetic parameters. These analyses consistently unveiled substantial disparities in their interactions with loop L3. We further synthesized a penicillin V derivative with increased hydrophobicity in the R1 side chain and co-crystallized it with NDM-1. Remarkably, this compound exhibited much stronger dynamic interplay with L3 during molecular dynamics simulation, showed much lower Km and kcat values, and demonstrated moderate inhibitory capacity to NDM-1 catalyzed meropenem hydrolysis. The data presented here may provide a strategic approach for designing mechanism-based MβL inhibitors focusing on structural elements external to the enzyme's active center.
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Affiliation(s)
- Xiangrui Shi
- Department of Obstetrics and Gynecology, Daping Hospital, Army Medical University, Chongqing 400042, China
| | - Yujie Dai
- Department of Obstetrics and Gynecology, Daping Hospital, Army Medical University, Chongqing 400042, China
| | - Zhu Lan
- Institute of Immunology, Army Medical University, Chongqing 400038, China
| | - Sheng Wang
- College of Life Science and Technology, Huazhong University of Science and Technology, 1037 Luoyu Avenue, Wuhan, Hubei 430074, China
| | - Liwei Cui
- Institute of Immunology, Army Medical University, Chongqing 400038, China
| | - Chengliang Xiao
- College of Life Science and Technology, Huazhong University of Science and Technology, 1037 Luoyu Avenue, Wuhan, Hubei 430074, China
| | - Kunhong Zhao
- Key Laboratory of Green Pesticide and Agricultural Bioengineering, Minister of Education, Guizhou University, Guiyang 550025, China
| | - Xiangyang Li
- Key Laboratory of Green Pesticide and Agricultural Bioengineering, Minister of Education, Guizhou University, Guiyang 550025, China.
| | - Wei Liu
- Institute of Immunology, Army Medical University, Chongqing 400038, China.
| | - Qinghua Zhang
- Department of Obstetrics and Gynecology, Daping Hospital, Army Medical University, Chongqing 400042, China.
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Sake SM, Zhang X, Rajak MK, Urbanek-Quaing M, Carpentier A, Gunesch AP, Grethe C, Matthaei A, Rückert J, Galloux M, Larcher T, Le Goffic R, Hontonnou F, Chatterjee AK, Johnson K, Morwood K, Rox K, Elgaher WAM, Huang J, Wetzke M, Hansen G, Fischer N, Eléouët JF, Rameix-Welti MA, Hirsch AKH, Herold E, Empting M, Lauber C, Schulz TF, Krey T, Haid S, Pietschmann T. Drug repurposing screen identifies lonafarnib as respiratory syncytial virus fusion protein inhibitor. Nat Commun 2024; 15:1173. [PMID: 38332002 PMCID: PMC10853176 DOI: 10.1038/s41467-024-45241-y] [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: 12/19/2022] [Accepted: 01/16/2024] [Indexed: 02/10/2024] Open
Abstract
Respiratory syncytial virus (RSV) is a common cause of acute lower respiratory tract infection in infants, older adults and the immunocompromised. Effective directly acting antivirals are not yet available for clinical use. To address this, we screen the ReFRAME drug-repurposing library consisting of 12,000 small molecules against RSV. We identify 21 primary candidates including RSV F and N protein inhibitors, five HSP90 and four IMPDH inhibitors. We select lonafarnib, a licensed farnesyltransferase inhibitor, and phase III candidate for hepatitis delta virus (HDV) therapy, for further follow-up. Dose-response analyses and plaque assays confirm the antiviral activity (IC50: 10-118 nM). Passaging of RSV with lonafarnib selects for phenotypic resistance and fixation of mutations in the RSV fusion protein (T335I and T400A). Lentiviral pseudotypes programmed with variant RSV fusion proteins confirm that lonafarnib inhibits RSV cell entry and that these mutations confer lonafarnib resistance. Surface plasmon resonance reveals RSV fusion protein binding of lonafarnib and co-crystallography identifies the lonafarnib binding site within RSV F. Oral administration of lonafarnib dose-dependently reduces RSV virus load in a murine infection model using female mice. Collectively, this work provides an overview of RSV drug repurposing candidates and establishes lonafarnib as a bona fide fusion protein inhibitor.
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Affiliation(s)
- Svenja M Sake
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Germany
| | - Xiaoyu Zhang
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Germany
| | - Manoj Kumar Rajak
- Institute of Virology, Hannover Medical School, Hannover, Germany
- Center of Structural and Cell Biology in Medicine, Institute of Biochemistry, University of Luebeck, Luebeck, Germany
| | - Melanie Urbanek-Quaing
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Germany
| | - Arnaud Carpentier
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Germany
| | - Antonia P Gunesch
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Germany
| | - Christina Grethe
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Germany
| | - Alina Matthaei
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Germany
| | - Jessica Rückert
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Marie Galloux
- Université Paris-Saclay, INRAE, UVSQ, VIM, Jouy-en-Josas, France
| | | | - Ronan Le Goffic
- Université Paris-Saclay, INRAE, UVSQ, VIM, Jouy-en-Josas, France
| | | | | | | | | | - Katharina Rox
- Department of Chemical Biology, Helmholtz Center of Infection Research, Braunschweig, Germany
- German Centre for Infection Research, Partner site Braunschweig-Hannover, Braunschweig, Germany
| | - Walid A M Elgaher
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS)-HZI, Saarbrücken, Germany
- Department of Pharmacy, Saarland University, Saarbrücken, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
| | - Jiabin Huang
- Insitute for Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Martin Wetzke
- Department for Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany
- German Center for Lung Research, Partner Site Hannover, BREATH, Hannover, Germany
| | - Gesine Hansen
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
- Department for Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany
- German Center for Lung Research, Partner Site Hannover, BREATH, Hannover, Germany
| | - Nicole Fischer
- Insitute for Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | - Marie-Anne Rameix-Welti
- Université Paris-Saclay, Université de Versailles St. Quentin; UMR 1173 (2I), INSERM; Assistance Publique des Hôpitaux de Paris, Hôpital Ambroise Paré, Laboratoire de Microbiologie, DMU15, Versailles, France
| | - Anna K H Hirsch
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS)-HZI, Saarbrücken, Germany
- Department of Pharmacy, Saarland University, Saarbrücken, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
- Helmholtz International Lab for Anti-infectives, HZI, Braunschweig, Germany
| | - Elisabeth Herold
- Center of Structural and Cell Biology in Medicine, Institute of Biochemistry, University of Luebeck, Luebeck, Germany
| | - Martin Empting
- German Centre for Infection Research, Partner site Braunschweig-Hannover, Braunschweig, Germany
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS)-HZI, Saarbrücken, Germany
- Department of Pharmacy, Saarland University, Saarbrücken, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
| | - Chris Lauber
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
| | - Thomas F Schulz
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Centre for Infection Research, Partner site Braunschweig-Hannover, Braunschweig, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
| | - Thomas Krey
- Institute of Virology, Hannover Medical School, Hannover, Germany
- Center of Structural and Cell Biology in Medicine, Institute of Biochemistry, University of Luebeck, Luebeck, Germany
- Centre for Structural Systems Biology (CSSB), Hamburg, Germany
- German Center for Infection Research, Partner Site Hamburg-Luebeck-Borstel-Riems, Luebeck, Germany
| | - Sibylle Haid
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Germany.
| | - Thomas Pietschmann
- Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Germany.
- German Centre for Infection Research, Partner site Braunschweig-Hannover, Braunschweig, Germany.
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany.
- Helmholtz International Lab for Anti-infectives, HZI, Braunschweig, Germany.
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42
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Bustad HJ, Christie MS, Laitaoja M, Aarsand AK, Martinez A, Jänis J, Kallio JP. One ring closer to a closure: the crystal structure of the ES 3 hydroxymethylbilane synthase intermediate. FEBS J 2024; 291:510-526. [PMID: 37863644 DOI: 10.1111/febs.16982] [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: 07/07/2023] [Revised: 09/08/2023] [Accepted: 10/17/2023] [Indexed: 10/22/2023]
Abstract
Hydroxymethylbilane synthase (HMBS), involved in haem biosynthesis, catalyses the head-to-tail coupling of four porphobilinogens (PBGs) via a dipyrromethane (DPM) cofactor. DPM is composed of two PBGs, and a hexapyrrole is built before the tetrapyrrolic 1-hydroxymethylbilane product is released. During this elongation, stable enzyme (E) intermediates are formed from the holoenzyme, with additional PBG substrates (S): ES, ES2 , ES3 and ES4 . Native PAGE and mass spectrometry of the acute intermittent porphyria (AIP)-associated HMBS variant p.Arg167Gln demonstrated an increased amount of ES3 . Kinetic parameters indicated catalytic dysfunction, however, the product release was not entirely prevented. Isolation and crystal structure analysis of the ES3 intermediate (PDB: 8PND) showed that a pentapyrrole was fully retained within the active site, revealing that polypyrrole elongation proceeds within the active site via a third interaction site, intermediate pyrrole site 3 (IPS3). The AIP-associated HMBS variant p.Arg195Cys, located on the opposite side to p.Arg167Gln in the active site, accumulated the ES4 intermediate in the presence of excess PBG, implying that product hydrolysis was obstructed. Arg167 is thus involved in all elongation steps and is a determinant for the rate of enzyme catalysis, whereas Arg195 is important for releasing the product. Moreover, by substituting residues in the vicinity of IPS3, our results indicate that a fully retained hexapyrrole could be hydrolysed in a novel site in proximity of the IPS3.
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Affiliation(s)
- Helene J Bustad
- Norwegian Porphyria Centre (NAPOS), Department for Medical Biochemistry and Pharmacology, Haukeland University Hospital, Bergen, Norway
| | - Marthe S Christie
- Norwegian Porphyria Centre (NAPOS), Department for Medical Biochemistry and Pharmacology, Haukeland University Hospital, Bergen, Norway
| | - Mikko Laitaoja
- Department of Chemistry, University of Eastern Finland, Joensuu, Finland
| | - Aasne K Aarsand
- Norwegian Porphyria Centre (NAPOS), Department for Medical Biochemistry and Pharmacology, Haukeland University Hospital, Bergen, Norway
- Norwegian Organization for Quality Improvement of Laboratory Examinations, Haraldsplass Deaconess Hospital, Bergen, Norway
| | | | - Janne Jänis
- Department of Chemistry, University of Eastern Finland, Joensuu, Finland
| | - Juha P Kallio
- Department of Biomedicine, University of Bergen, Norway
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43
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Guerrero L, Ebrahim A, Riley BT, Kim M, Huang Q, Finke AD, Keedy DA. Pushed to extremes: distinct effects of high temperature versus pressure on the structure of STEP. Commun Biol 2024; 7:59. [PMID: 38216663 PMCID: PMC10786866 DOI: 10.1038/s42003-023-05609-0] [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: 05/09/2023] [Accepted: 11/20/2023] [Indexed: 01/14/2024] Open
Abstract
Protein function hinges on small shifts of three-dimensional structure. Elevating temperature or pressure may provide experimentally accessible insights into such shifts, but the effects of these distinct perturbations on protein structures have not been compared in atomic detail. To quantitatively explore these two axes, we report the first pair of structures at physiological temperature versus. high pressure for the same protein, STEP (PTPN5). We show that these perturbations have distinct and surprising effects on protein volume, patterns of ordered solvent, and local backbone and side-chain conformations. This includes interactions between key catalytic loops only at physiological temperature, and a distinct conformational ensemble for another active-site loop only at high pressure. Strikingly, in torsional space, physiological temperature shifts STEP toward previously reported active-like states, while high pressure shifts it toward a previously uncharted region. Altogether, our work indicates that temperature and pressure are complementary, powerful, fundamental macromolecular perturbations.
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Affiliation(s)
- Liliana Guerrero
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, NY, 10031, USA
- PhD Program in Biochemistry, CUNY Graduate Center, New York, NY, 10016, USA
| | - Ali Ebrahim
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, NY, 10031, USA
| | - Blake T Riley
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, NY, 10031, USA
| | - Minyoung Kim
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, NY, 10031, USA
- Department of Molecular Biology, Princeton University, Princeton, NJ, 08544, USA
| | - Qingqiu Huang
- Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, NY, 14853, USA
| | - Aaron D Finke
- Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, NY, 14853, USA
| | - Daniel A Keedy
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, NY, 10031, USA.
- Department of Chemistry and Biochemistry, City College of New York, New York, NY, 10031, USA.
- PhD Programs in Biochemistry, Biology, & Chemistry, CUNY Graduate Center, New York, NY, 10016, USA.
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44
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Park S, Fan J, Chamakuri S, Palaniappan M, Sharma K, Qin X, Wang J, Tan Z, Judge A, Hu L, Sankaran B, Li F, Prasad BVV, Matzuk MM, Palzkill T. Exploiting the Carboxylate-Binding Pocket of β-Lactamase Enzymes Using a Focused DNA-Encoded Chemical Library. J Med Chem 2024; 67:620-642. [PMID: 38117688 DOI: 10.1021/acs.jmedchem.3c01834] [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: 12/22/2023]
Abstract
β-Lactamase enzymes hydrolyze and thereby provide bacterial resistance to the important β-lactam class of antibiotics. The OXA-48 and NDM-1 β-lactamases cause resistance to the last-resort β-lactams, carbapenems, leading to a serious public health threat. Here, we utilized DNA-encoded chemical library (DECL) technology to discover novel β-lactamase inhibitors. We exploited the β-lactamase enzyme-substrate binding interactions and created a DECL targeting the carboxylate-binding pocket present in all β-lactamases. A library of 106 compounds, each containing a carboxylic acid or a tetrazole as an enzyme recognition element, was designed, constructed, and used to identify OXA-48 and NDM-1 inhibitors with micromolar to nanomolar potency. Further optimization led to NDM-1 inhibitors with increased potencies and biological activities. This work demonstrates that the carboxylate-binding pocket-targeting DECL, designed based on substrate binding information, aids in inhibitor identification and led to the discovery of novel non-β-lactam pharmacophores for the development of β-lactamase inhibitors for enzymes of different structural and mechanistic classes.
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Affiliation(s)
- Suhyeorn Park
- Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, Texas 77030, United States
| | - Jiayi Fan
- Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, Texas 77030, United States
| | - Srinivas Chamakuri
- Center for Drug Discovery, Department of Pathology & Immunology, Baylor College of Medicine, Houston, Texas 77030, United States
| | - Murugesan Palaniappan
- Center for Drug Discovery, Department of Pathology & Immunology, Baylor College of Medicine, Houston, Texas 77030, United States
| | - Kiran Sharma
- Center for Drug Discovery, Department of Pathology & Immunology, Baylor College of Medicine, Houston, Texas 77030, United States
| | - Xuan Qin
- Center for Drug Discovery, Department of Pathology & Immunology, Baylor College of Medicine, Houston, Texas 77030, United States
| | - Jian Wang
- Center for Drug Discovery, Department of Pathology & Immunology, Baylor College of Medicine, Houston, Texas 77030, United States
| | - Zhi Tan
- Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, Texas 77030, United States
- Center for Drug Discovery, Department of Pathology & Immunology, Baylor College of Medicine, Houston, Texas 77030, United States
| | - Allison Judge
- Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, Texas 77030, United States
| | - Liya Hu
- Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, Texas 77030, United States
| | - Banumathi Sankaran
- Berkeley Center for Structural Biology, Advanced Light Source, Lawrence Berkeley National Lab, Berkeley, California 94720, United States
| | - Feng Li
- Center for Drug Discovery, Department of Pathology & Immunology, Baylor College of Medicine, Houston, Texas 77030, United States
| | - B V Venkataram Prasad
- Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, Texas 77030, United States
| | - Martin M Matzuk
- Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, Texas 77030, United States
- Center for Drug Discovery, Department of Pathology & Immunology, Baylor College of Medicine, Houston, Texas 77030, United States
| | - Timothy Palzkill
- Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, Texas 77030, United States
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45
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Sluchanko NN, Maksimov EG, Slonimskiy YB, Varfolomeeva LA, Bukhanko AY, Egorkin NA, Tsoraev GV, Khrenova MG, Ge B, Qin S, Boyko KM, Popov VO. Structural framework for the understanding spectroscopic and functional signatures of the cyanobacterial Orange Carotenoid Protein families. Int J Biol Macromol 2024; 254:127874. [PMID: 37939760 DOI: 10.1016/j.ijbiomac.2023.127874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 10/23/2023] [Accepted: 11/01/2023] [Indexed: 11/10/2023]
Abstract
The Orange Carotenoid Protein (OCP) is a unique photoreceptor crucial for cyanobacterial photoprotection. Best studied Synechocystis sp. PCC 6803 OCP belongs to the large OCP1 family. Downregulated by the Fluorescence Recovery Protein (FRP) in low-light, high-light-activated OCP1 binds to the phycobilisomes and performs non-photochemical quenching. Recently discovered families OCP2 and OCP3 remain structurally and functionally underexplored, and no systematic comparative studies have ever been conducted. Here we present two first crystal structures of OCP2 from morphoecophysiologically different cyanobacteria and provide their comprehensive structural, spectroscopic and functional comparison with OCP1, the recently described OCP3 and all-OCP ancestor. Structures enable correlation of spectroscopic signatures with the effective number of hydrogen and discovered here chalcogen bonds anchoring the ketocarotenoid in OCP, as well as with the rotation of the echinenone's β-ionone ring in the CTD. Structural data also helped rationalize the observed differences in OCP/FRP and OCP/phycobilisome functional interactions. These data are expected to foster OCP research and applications in optogenetics, targeted carotenoid delivery and cyanobacterial biomass engineering.
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Affiliation(s)
- Nikolai N Sluchanko
- A.N. Bach Institute of Biochemistry, Federal Research Centre of Biotechnology of the Russian Academy of Sciences, Moscow 119071, Russia.
| | - Eugene G Maksimov
- M.V. Lomonosov Moscow State University, Faculty of Biology, Moscow 119991, Russia
| | - Yury B Slonimskiy
- A.N. Bach Institute of Biochemistry, Federal Research Centre of Biotechnology of the Russian Academy of Sciences, Moscow 119071, Russia
| | - Larisa A Varfolomeeva
- A.N. Bach Institute of Biochemistry, Federal Research Centre of Biotechnology of the Russian Academy of Sciences, Moscow 119071, Russia
| | - Antonina Y Bukhanko
- M.V. Lomonosov Moscow State University, Faculty of Biology, Moscow 119991, Russia
| | - Nikita A Egorkin
- A.N. Bach Institute of Biochemistry, Federal Research Centre of Biotechnology of the Russian Academy of Sciences, Moscow 119071, Russia; M.V. Lomonosov Moscow State University, Faculty of Biology, Moscow 119991, Russia
| | - Georgy V Tsoraev
- A.N. Bach Institute of Biochemistry, Federal Research Centre of Biotechnology of the Russian Academy of Sciences, Moscow 119071, Russia
| | - Maria G Khrenova
- A.N. Bach Institute of Biochemistry, Federal Research Centre of Biotechnology of the Russian Academy of Sciences, Moscow 119071, Russia; Lomonosov Moscow State University, Chemistry Department, Moscow 119991, Russia
| | - Baosheng Ge
- China University of Petroleum (Huadong), College of Chemistry and Chemical Engineering, Qingdao 266580, People's Republic of China
| | - Song Qin
- Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, People's Republic of China.
| | - Konstantin M Boyko
- A.N. Bach Institute of Biochemistry, Federal Research Centre of Biotechnology of the Russian Academy of Sciences, Moscow 119071, Russia
| | - Vladimir O Popov
- A.N. Bach Institute of Biochemistry, Federal Research Centre of Biotechnology of the Russian Academy of Sciences, Moscow 119071, Russia; M.V. Lomonosov Moscow State University, Faculty of Biology, Moscow 119991, Russia
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46
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Akutsu Y, Fujiwara T, Suzuki R, Nishigaya Y, Yamazaki T. Juglone, a plant-derived 1,4-naphthoquinone, binds to hydroxylamine oxidoreductase and inhibits the electron transfer to cytochrome c554. Appl Environ Microbiol 2023; 89:e0129123. [PMID: 38009977 PMCID: PMC10734522 DOI: 10.1128/aem.01291-23] [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: 08/10/2023] [Accepted: 09/20/2023] [Indexed: 11/29/2023] Open
Abstract
IMPORTANCE Nitrification, the microbial conversion of ammonia to nitrate via nitrite, plays a pivotal role in the global nitrogen cycle. However, the excessive use of ammonium-based fertilizers in agriculture has disrupted this cycle, leading to groundwater pollution and greenhouse gas emissions. In this study, we have demonstrated the inhibitory effects of plant-derived juglone and related 1,4-naphthoquinones on the nitrification process in Nitrosomonas europaea. Notably, the inhibition mechanism is elucidated in which 1,4-naphthoquinones interact with hydroxylamine oxidoreductase, disrupting the electron transfer to cytochrome c554, a physiological electron acceptor. These findings support the notion that phytochemicals can impede nitrification by interfering with the essential electron transfer process in ammonia oxidation. The findings presented in this article offer valuable insights for the development of strategies aimed at the management of nitrification, reduction of fertilizer utilization, and mitigation of greenhouse gas emissions.
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Affiliation(s)
- Yukie Akutsu
- Research Center for Advanced Analysis, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki, Japan
| | - Takaaki Fujiwara
- Research Center for Advanced Analysis, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki, Japan
| | - Rintaro Suzuki
- Research Center for Advanced Analysis, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki, Japan
| | | | - Toshimasa Yamazaki
- Research Center for Advanced Analysis, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki, Japan
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47
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Simmons CR, Buchberger A, Henry SJW, Novacek A, Fahmi NE, MacCulloch T, Stephanopoulos N, Yan H. Site-Specific Arrangement and Structure Determination of Minor Groove Binding Molecules in Self-Assembled Three-Dimensional DNA Crystals. J Am Chem Soc 2023; 145:26075-26085. [PMID: 37987645 PMCID: PMC10789492 DOI: 10.1021/jacs.3c07802] [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: 11/22/2023]
Abstract
The structural analysis of guest molecules in rationally designed and self-assembling DNA crystals has proven an elusive goal since its conception. Oligonucleotide frameworks provide an especially attractive route toward studying DNA-binding molecules by using three-dimensional lattices with defined sequence and structure. In this work, we site-specifically position a suite of minor groove binding molecules, and solve their structures via X-ray crystallography as a proof-of-principle toward scaffolding larger guest species. Two crystal motifs were used to precisely immobilize the molecules DAPI, Hoechst, and netropsin at defined positions in the lattice, allowing us to control occupancy within the crystal. We also solved the structure of a three-ring imidazole-pyrrole-pyrrole polyamide molecule, which sequence-specifically packs in an antiparallel dimeric arrangement within the minor groove. Finally, we engineered a crystal designed to position both netropsin and the polyamide at two distinct locations within the same lattice. Our work elucidates the design principles for the spatial arrangement of functional guests within lattices and opens new potential opportunities for the use of DNA crystals to display and structurally characterize small molecules, peptides, and ultimately proteins of unknown structure.
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Affiliation(s)
- Chad R Simmons
- Biodesign Center for Molecular Design and Biomimetics, Arizona State University 1001 S. McAllister Ave., Tempe, Arizona 85287, United States
| | - Alex Buchberger
- Biodesign Center for Molecular Design and Biomimetics, Arizona State University 1001 S. McAllister Ave., Tempe, Arizona 85287, United States
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287,United States
| | - Skylar J W Henry
- Biodesign Center for Molecular Design and Biomimetics, Arizona State University 1001 S. McAllister Ave., Tempe, Arizona 85287, United States
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287,United States
| | - Alexandra Novacek
- Biodesign Center for Molecular Design and Biomimetics, Arizona State University 1001 S. McAllister Ave., Tempe, Arizona 85287, United States
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287,United States
| | - Nour Eddine Fahmi
- Biodesign Center for Molecular Design and Biomimetics, Arizona State University 1001 S. McAllister Ave., Tempe, Arizona 85287, United States
| | - Tara MacCulloch
- Biodesign Center for Molecular Design and Biomimetics, Arizona State University 1001 S. McAllister Ave., Tempe, Arizona 85287, United States
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287,United States
| | - Nicholas Stephanopoulos
- Biodesign Center for Molecular Design and Biomimetics, Arizona State University 1001 S. McAllister Ave., Tempe, Arizona 85287, United States
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287,United States
| | - Hao Yan
- Biodesign Center for Molecular Design and Biomimetics, Arizona State University 1001 S. McAllister Ave., Tempe, Arizona 85287, United States
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287,United States
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48
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Tan B, Zhang X, Ansari A, Jadhav P, Tan H, Li K, Chopra A, Ford A, Chi X, Ruiz FX, Arnold E, Deng X, Wang J. Design of SARS-CoV-2 papain-like protease inhibitor with antiviral efficacy in a mouse model. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.01.569653. [PMID: 38076941 PMCID: PMC10705561 DOI: 10.1101/2023.12.01.569653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/18/2023]
Abstract
The emergence of SARS-CoV-2 variants and drug-resistant mutants calls for additional oral antivirals. The SARS-CoV-2 papain-like protease (PLpro) is a promising but challenging drug target. In this study, we designed and synthesized 85 noncovalent PLpro inhibitors that bind to the newly discovered Val70Ub site and the known BL2 groove pocket. Potent compounds inhibited PLpro with inhibitory constant Ki values from 13.2 to 88.2 nM. The co-crystal structures of PLpro with eight leads revealed their interaction modes. The in vivo lead Jun12682 inhibited SARS-CoV-2 and its variants, including nirmatrelvir-resistant strains with EC50 from 0.44 to 2.02 μM. Oral treatment with Jun12682 significantly improved survival and reduced lung viral loads and lesions in a SARS-CoV-2 infection mouse model, suggesting PLpro inhibitors are promising oral SARS-CoV-2 antiviral candidates.
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Affiliation(s)
- Bin Tan
- Department of Medicinal Chemistry, Ernest Mario School of Pharmacy, Rutgers, the State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Xiaoming Zhang
- Department Physiological Sciences, College of Veterinary Medicine, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Ahmadullah Ansari
- Center for Advanced Biotechnology and Medicine, Rutgers, the State University of New Jersey, Piscataway, NJ, 08854, USA
- Department of Chemistry and Chemical Biology, Rutgers, the State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Prakash Jadhav
- Department of Medicinal Chemistry, Ernest Mario School of Pharmacy, Rutgers, the State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Haozhou Tan
- Department of Medicinal Chemistry, Ernest Mario School of Pharmacy, Rutgers, the State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Kan Li
- Department of Medicinal Chemistry, Ernest Mario School of Pharmacy, Rutgers, the State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Ashima Chopra
- Center for Advanced Biotechnology and Medicine, Rutgers, the State University of New Jersey, Piscataway, NJ, 08854, USA
- Department of Chemistry and Chemical Biology, Rutgers, the State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Alexandra Ford
- Deprtment of Veterinary Pathobiology, College of Veterinary Medicine, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Xiang Chi
- Department Physiological Sciences, College of Veterinary Medicine, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Francesc Xavier Ruiz
- Center for Advanced Biotechnology and Medicine, Rutgers, the State University of New Jersey, Piscataway, NJ, 08854, USA
- Department of Chemistry and Chemical Biology, Rutgers, the State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Eddy Arnold
- Center for Advanced Biotechnology and Medicine, Rutgers, the State University of New Jersey, Piscataway, NJ, 08854, USA
- Department of Chemistry and Chemical Biology, Rutgers, the State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Xufang Deng
- Department Physiological Sciences, College of Veterinary Medicine, Oklahoma State University, Stillwater, OK, 74078, USA
- Oklahoma Center for Respiratory and Infectious Diseases, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Jun Wang
- Department of Medicinal Chemistry, Ernest Mario School of Pharmacy, Rutgers, the State University of New Jersey, Piscataway, NJ, 08854, USA
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49
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Christou NE, Apostolopoulou V, Melo DVM, Ruppert M, Fadini A, Henkel A, Sprenger J, Oberthuer D, Günther S, Pateras A, Rahmani Mashhour A, Yefanov OM, Galchenkova M, Reinke PYA, Kremling V, Scheer TES, Lange ER, Middendorf P, Schubert R, De Zitter E, Lumbao-Conradson K, Herrmann J, Rahighi S, Kunavar A, Beale EV, Beale JH, Cirelli C, Johnson PJM, Dworkowski F, Ozerov D, Bertrand Q, Wranik M, Bacellar C, Bajt S, Wakatsuki S, Sellberg JA, Huse N, Turk D, Chapman HN, Lane TJ. Time-resolved crystallography captures light-driven DNA repair. Science 2023; 382:1015-1020. [PMID: 38033070 DOI: 10.1126/science.adj4270] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 10/05/2023] [Indexed: 12/02/2023]
Abstract
Photolyase is an enzyme that uses light to catalyze DNA repair. To capture the reaction intermediates involved in the enzyme's catalytic cycle, we conducted a time-resolved crystallography experiment. We found that photolyase traps the excited state of the active cofactor, flavin adenine dinucleotide (FAD), in a highly bent geometry. This excited state performs electron transfer to damaged DNA, inducing repair. We show that the repair reaction, which involves the lysis of two covalent bonds, occurs through a single-bond intermediate. The transformation of the substrate into product crowds the active site and disrupts hydrogen bonds with the enzyme, resulting in stepwise product release, with the 3' thymine ejected first, followed by the 5' base.
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Affiliation(s)
- Nina-Eleni Christou
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Virginia Apostolopoulou
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Diogo V M Melo
- European XFEL GmbH, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Matthias Ruppert
- Institute for Nanostructure and Solid-State Physics, CFEL Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Alisia Fadini
- Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, UK
| | - Alessandra Henkel
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Janina Sprenger
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Dominik Oberthuer
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Sebastian Günther
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Anastasios Pateras
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Aida Rahmani Mashhour
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Oleksandr M Yefanov
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Marina Galchenkova
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Patrick Y A Reinke
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Viviane Kremling
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - T Emilie S Scheer
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Esther R Lange
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Philipp Middendorf
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Robin Schubert
- European XFEL GmbH, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Elke De Zitter
- Université Grenoble Alpes, CEA, CNRS, Institut de Biologie Structurale, 38000 Grenoble, France
| | - Koya Lumbao-Conradson
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Rd, Menlo Park, CA 94025, USA
| | - Jonathan Herrmann
- Department of Structural Biology, Stanford University, 318 Campus Drive West, Stanford, CA 94305-5151, USA
| | - Simin Rahighi
- Department of Structural Biology, Stanford University, 318 Campus Drive West, Stanford, CA 94305-5151, USA
| | - Ajda Kunavar
- Laboratory for Fluid Dynamics and Thermodynamics, Faculty of Mechanical Engineering, University of Ljubljana, Aškerčeva 6, 1000 Ljubljana, Slovenia
| | - Emma V Beale
- Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - John H Beale
- Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | | | | | | | - Dmitry Ozerov
- Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | | | | | | | - Saša Bajt
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Soichi Wakatsuki
- Department of Structural Biology, Stanford University, 318 Campus Drive West, Stanford, CA 94305-5151, USA
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Rd, Menlo Park, CA 94025, USA
| | - Jonas A Sellberg
- Biomedical and X-ray Physics, Department of Applied Physics, AlbaNova University Center, KTH Royal Institute of Technology, S-106 91 Stockholm, Sweden
| | - Nils Huse
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
- Institute for Nanostructure and Solid-State Physics, CFEL Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Dušan Turk
- Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia
- Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins, Jamova 39, 1000 Ljubljana, Slovenia
| | - Henry N Chapman
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
- Department of Physics, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Thomas J Lane
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
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50
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Rathbone HW, Laos AJ, Michie KA, Iranmanesh H, Biazik J, Goodchild SC, Thordarson P, Green BR, Curmi PMG. Molecular dissection of the soluble photosynthetic antenna from the cryptophyte alga Hemiselmis andersenii. Commun Biol 2023; 6:1158. [PMID: 37957226 PMCID: PMC10643455 DOI: 10.1038/s42003-023-05508-4] [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: 07/27/2023] [Accepted: 10/25/2023] [Indexed: 11/15/2023] Open
Abstract
Cryptophyte algae have a unique phycobiliprotein light-harvesting antenna that fills a spectral gap in chlorophyll absorption from photosystems. However, it is unclear how the antenna transfers energy efficiently to these photosystems. We show that the cryptophyte Hemiselmis andersenii expresses an energetically complex antenna comprising three distinct spectrotypes of phycobiliprotein, each composed of two αβ protomers but with different quaternary structures arising from a diverse α subunit family. We report crystal structures of the major phycobiliprotein from each spectrotype. Two-thirds of the antenna consists of open quaternary form phycobiliproteins acting as primary photon acceptors. These are supplemented by a newly discovered open-braced form (~15%), where an insertion in the α subunit produces ~10 nm absorbance red-shift. The final components (~15%) are closed forms with a long wavelength spectral feature due to substitution of a single chromophore. This chromophore is present on only one β subunit where asymmetry is dictated by the corresponding α subunit. This chromophore creates spectral overlap with chlorophyll, thus bridging the energetic gap between the phycobiliprotein antenna and the photosystems. We propose that the macromolecular organization of the cryptophyte antenna consists of bulk open and open-braced forms that transfer excitations to photosystems via this bridging closed form phycobiliprotein.
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Affiliation(s)
- Harry W Rathbone
- School of Physics, The University of New South Wales, Sydney, NSW, 2052, Australia
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, 2052, Australia
- UMR144 Cell Biology and Cancer, Institut Curie, Paris, 75005, France
| | - Alistair J Laos
- UNSW RNA Institute and School of Chemistry, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - Katharine A Michie
- School of Physics, The University of New South Wales, Sydney, NSW, 2052, Australia
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, 2052, Australia
- Mark Wainwright Analytical Centre, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - Hasti Iranmanesh
- School of Physics, The University of New South Wales, Sydney, NSW, 2052, Australia
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - Joanna Biazik
- Mark Wainwright Analytical Centre, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - Sophia C Goodchild
- School of Molecular Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Pall Thordarson
- UNSW RNA Institute and School of Chemistry, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - Beverley R Green
- Department of Botany, University of British Columbia, Vancouver, BC, Canada
| | - Paul M G Curmi
- School of Physics, The University of New South Wales, Sydney, NSW, 2052, Australia.
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, 2052, Australia.
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