1
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Tsuge H, Habuka N, Yoshida T. General ADP-Ribosylation Mechanism Based on the Structure of ADP-Ribosyltransferase-Substrate Complexes. Toxins (Basel) 2024; 16:313. [PMID: 39057953 PMCID: PMC11281641 DOI: 10.3390/toxins16070313] [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: 06/05/2024] [Revised: 07/06/2024] [Accepted: 07/09/2024] [Indexed: 07/28/2024] Open
Abstract
ADP-ribosylation is a ubiquitous modification of proteins and other targets, such as nucleic acids, that regulates various cellular functions in all kingdoms of life. Furthermore, these ADP-ribosyltransferases (ARTs) modify a variety of substrates and atoms. It has been almost 60 years since ADP-ribosylation was discovered. Various ART structures have been revealed with cofactors (NAD+ or NAD+ analog). However, we still do not know the molecular mechanisms of ART. It needs to be better understood how ART specifies the target amino acids or bases. For this purpose, more information is needed about the tripartite complex structures of ART, the cofactors, and the substrates. The tripartite complex is essential to understand the mechanism of ADP-ribosyltransferase. This review updates the general ADP-ribosylation mechanism based on ART tripartite complex structures.
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Affiliation(s)
- Hideaki Tsuge
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto 6038555, Japan
| | - Noriyuki Habuka
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto 6038555, Japan
| | - Toru Yoshida
- Faculty of Sciences, Japan Women’s University, Tokyo 1120015, Japan
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2
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Cihlova B, Lu Y, Mikoč A, Schuller M, Ahel I. Specificity of DNA ADP-Ribosylation Reversal by NADARs. Toxins (Basel) 2024; 16:208. [PMID: 38787060 PMCID: PMC11125620 DOI: 10.3390/toxins16050208] [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: 03/18/2024] [Revised: 04/23/2024] [Accepted: 04/24/2024] [Indexed: 05/25/2024] Open
Abstract
Recent discoveries establish DNA and RNA as bona fide substrates for ADP-ribosylation. NADAR ("NAD- and ADP-ribose"-associated) enzymes reverse guanine ADP-ribosylation and serve as antitoxins in the DarT-NADAR operon. Although NADARs are widespread across prokaryotes, eukaryotes, and viruses, their specificity and broader physiological roles remain poorly understood. Using phylogenetic and biochemical analyses, we further explore de-ADP-ribosylation activity and antitoxin functions of NADAR domains. We demonstrate that different subfamilies of NADAR proteins from representative E. coli strains and an E. coli-infecting phage retain biochemical activity while displaying specificity in providing protection from toxic guanine ADP-ribosylation in cells. Furthermore, we identify a myxobacterial enzyme within the YbiA subfamily that functions as an antitoxin for its associated DarT-unrelated ART toxin, which we termed YarT, thus presenting a hitherto uncharacterised ART-YbiA toxin-antitoxin pair. Our studies contribute to the burgeoning field of DNA ADP-ribosylation, supporting its physiological relevance within and beyond bacterial toxin-antitoxin systems. Notably, the specificity and confinement of NADARs to non-mammals infer their potential as highly specific targets for antimicrobial drugs with minimal off-target effects.
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Affiliation(s)
- Bara Cihlova
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK; (B.C.); (Y.L.)
| | - Yang Lu
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK; (B.C.); (Y.L.)
| | - Andreja Mikoč
- Division of Molecular Biology, Ruđer Bošković Institute, 10000 Zagreb, Croatia;
| | - Marion Schuller
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK; (B.C.); (Y.L.)
| | - Ivan Ahel
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK; (B.C.); (Y.L.)
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3
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Schuller M, Raggiaschi R, Mikolcevic P, Rack JGM, Ariza A, Zhang Y, Ledermann R, Tang C, Mikoc A, Ahel I. Molecular basis for the reversible ADP-ribosylation of guanosine bases. Mol Cell 2023:S1097-2765(23)00457-4. [PMID: 37390817 DOI: 10.1016/j.molcel.2023.06.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 04/13/2023] [Accepted: 06/08/2023] [Indexed: 07/02/2023]
Abstract
Modification of nucleic acids by ADP-ribosylation is catalyzed by various ADP-ribosyltransferases, including the DarT enzyme. The latter is part of the bacterial toxin-antitoxin (TA) system DarTG, which was shown to provide control of DNA replication and bacterial growth as well as protection against bacteriophages. Two subfamilies have been identified, DarTG1 and DarTG2, which are distinguished by their associated antitoxins. While DarTG2 catalyzes reversible ADP-ribosylation of thymidine bases employing a macrodomain as antitoxin, the DNA ADP-ribosylation activity of DarTG1 and the biochemical function of its antitoxin, a NADAR domain, are as yet unknown. Using structural and biochemical approaches, we show that DarT1-NADAR is a TA system for reversible ADP-ribosylation of guanosine bases. DarT1 evolved the ability to link ADP-ribose to the guanine amino group, which is specifically hydrolyzed by NADAR. We show that guanine de-ADP-ribosylation is also conserved among eukaryotic and non-DarT-associated NADAR members, indicating a wide distribution of reversible guanine modifications beyond DarTG systems.
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Affiliation(s)
- Marion Schuller
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | | | - Petra Mikolcevic
- Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
| | - Johannes G M Rack
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Antonio Ariza
- School of Biosciences, University of Sheffield, Sheffield, UK
| | - YuGeng Zhang
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | | | - Christoph Tang
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Andreja Mikoc
- Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
| | - Ivan Ahel
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK.
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4
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Henao L, Zade RSH, Restrepo S, Husserl J, Abeel T. Genomes of four Streptomyces strains reveal insights into putative new species and pathogenicity of scab-causing organisms. BMC Genomics 2023; 24:143. [PMID: 36959546 PMCID: PMC10037901 DOI: 10.1186/s12864-023-09190-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 02/15/2023] [Indexed: 03/25/2023] Open
Abstract
Genomes of four Streptomyces isolates, two putative new species (Streptomyces sp. JH14 and Streptomyces sp. JH34) and two non thaxtomin-producing pathogens (Streptomyces sp. JH002 and Streptomyces sp. JH010) isolated from potato fields in Colombia were selected to investigate their taxonomic classification, their pathogenicity, and the production of unique secondary metabolites of Streptomycetes inhabiting potato crops in this region. The average nucleotide identity (ANI) value calculated between Streptomyces sp. JH34 and its closest relatives (92.23%) classified this isolate as a new species. However, Streptomyces sp. JH14 could not be classified as a new species due to the lack of genomic data of closely related strains. Phylogenetic analysis based on 231 single-copy core genes, confirmed that the two pathogenic isolates (Streptomyces sp. JH010 and JH002) belong to Streptomyces pratensis and Streptomyces xiamenensis, respectively, are distant from the most well-known pathogenic species, and belong to two different lineages. We did not find orthogroups of protein-coding genes characteristic of scab-causing Streptomycetes shared by all known pathogenic species. Most genes involved in biosynthesis of known virulence factors are not present in the scab-causing isolates (Streptomyces sp. JH002 and Streptomyces sp. JH010). However, Tat-system substrates likely involved in pathogenicity in Streptomyces sp. JH002 and Streptomyces sp. JH010 were identified. Lastly, the presence of a putative mono-ADP-ribosyl transferase, homologous to the virulence factor scabin, was confirmed in Streptomyces sp. JH002. The described pathogenic isolates likely produce virulence factors uncommon in Streptomyces species, including a histidine phosphatase and a metalloprotease potentially produced by Streptomyces sp. JH002, and a pectinesterase, potentially produced by Streptomyces sp. JH010. Biosynthetic gene clusters (BGCs) showed the presence of clusters associated with the synthesis of medicinal compounds and BGCs potentially linked to pathogenicity in Streptomyces sp. JH010 and JH002. Interestingly, BGCs that have not been previously reported were also found. Our findings suggest that the four isolates produce novel secondary metabolites and metabolites with medicinal properties.
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Affiliation(s)
- Laura Henao
- Department of Civil and Environmental Engineering, Universidad de los Andes, 111711, Bogotá, Colombia
| | | | - Silvia Restrepo
- Laboratory of Mycology and Phytopathology - (LAMFU), Department of Chemical and Food Engineering, Universidad de los Andes, 111711, Bogotá, Colombia
| | - Johana Husserl
- Department of Civil and Environmental Engineering, Universidad de los Andes, 111711, Bogotá, Colombia
| | - Thomas Abeel
- Delft Bioinformatics Lab, Delft University of Technology, 2628 XE, Delft, Netherlands.
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, MA, 02142, USA.
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5
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Schuller M, Ahel I. Beyond protein modification: the rise of non-canonical ADP-ribosylation. Biochem J 2022; 479:463-477. [PMID: 35175282 PMCID: PMC8883491 DOI: 10.1042/bcj20210280] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 01/18/2022] [Accepted: 01/21/2022] [Indexed: 12/22/2022]
Abstract
ADP-ribosylation has primarily been known as post-translational modification of proteins. As signalling strategy conserved in all domains of life, it modulates substrate activity, localisation, stability or interactions, thereby regulating a variety of cellular processes and microbial pathogenicity. Yet over the last years, there is increasing evidence of non-canonical forms of ADP-ribosylation that are catalysed by certain members of the ADP-ribosyltransferase family and go beyond traditional protein ADP-ribosylation signalling. New macromolecular targets such as nucleic acids and new ADP-ribose derivatives have been established, notably extending the repertoire of ADP-ribosylation signalling. Based on the physiological relevance known so far, non-canonical ADP-ribosylation deserves its recognition next to the traditional protein ADP-ribosylation modification and which we therefore review in the following.
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Affiliation(s)
- Marion Schuller
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, U.K
| | - Ivan Ahel
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, U.K
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6
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McCarthy M, Goncalves M, Powell H, Morey B, Turner M, Merrill AR. A Structural Approach to Anti-Virulence: A Discovery Pipeline. Microorganisms 2021; 9:microorganisms9122514. [PMID: 34946116 PMCID: PMC8704661 DOI: 10.3390/microorganisms9122514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 11/27/2021] [Accepted: 11/30/2021] [Indexed: 11/25/2022] Open
Abstract
The anti-virulence strategy is designed to prevent bacterial virulence factors produced by pathogenic bacteria from initiating and sustaining an infection. One family of bacterial virulence factors is the mono-ADP-ribosyltransferase toxins, which are produced by pathogens as tools to compromise the target host cell. These toxins are bacterial enzymes that exploit host cellular NAD+ as the donor substrate to modify an essential macromolecule acceptor target in the host cell. This biochemical reaction modifies the target macromolecule (often protein or DNA) and functions in a binary fashion to turn the target activity on or off by blocking or impairing a critical process or pathway in the host. A structural biology approach to the anti-virulence method to neutralize the cytotoxic effect of these factors requires the search and design of small molecules that bind tightly to the enzyme active site and prevent catalytic function essentially disarming the pathogen. This method requires a high-resolution structure to serve as the model for small molecule inhibitor development, which illuminates the path to drug development. This alternative strategy to antibiotic therapy represents a paradigm shift that may circumvent multi-drug resistance in the offending microbe through anti-virulence therapy. In this report, the rationale for the anti-virulence structural approach will be discussed along with recent efforts to apply this method to treat honey bee diseases using natural products.
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7
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Mikolčević P, Hloušek-Kasun A, Ahel I, Mikoč A. ADP-ribosylation systems in bacteria and viruses. Comput Struct Biotechnol J 2021; 19:2366-2383. [PMID: 34025930 PMCID: PMC8120803 DOI: 10.1016/j.csbj.2021.04.023] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 04/07/2021] [Accepted: 04/07/2021] [Indexed: 12/30/2022] Open
Abstract
ADP-ribosylation is an ancient posttranslational modification present in all kingdoms of life. The system likely originated in bacteria where it functions in inter- and intra-species conflict, stress response and pathogenicity. It was repeatedly adopted via lateral transfer by eukaryotes, including humans, where it has a pivotal role in epigenetics, DNA-damage repair, apoptosis, and other crucial pathways including the immune response to pathogenic bacteria and viruses. In other words, the same ammunition used by pathogens is adapted by eukaryotes to fight back. While we know quite a lot about the eukaryotic system, expanding rather patchy knowledge on bacterial and viral ADP-ribosylation would give us not only a better understanding of the system as a whole but a fighting advantage in this constant arms race. By writing this review we hope to put into focus the available information and give a perspective on how this system works and can be exploited in the search for therapeutic targets in the future. The relevance of the subject is especially highlighted by the current situation of being amid the world pandemic caused by a virus harbouring and dependent on a representative of such a system.
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Affiliation(s)
- Petra Mikolčević
- Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
| | | | - Ivan Ahel
- Sir William Dunn School of Pathology, University of Oxford, UK
| | - Andreja Mikoč
- Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
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8
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Wyżewski Z, Gradowski M, Krysińska M, Dudkiewicz M, Pawłowski K. A novel predicted ADP-ribosyltransferase-like family conserved in eukaryotic evolution. PeerJ 2021; 9:e11051. [PMID: 33854844 PMCID: PMC7955679 DOI: 10.7717/peerj.11051] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 02/11/2021] [Indexed: 01/12/2023] Open
Abstract
The presence of many completely uncharacterized proteins, even in well-studied organisms such as humans, seriously hampers full understanding of the functioning of the living cells. ADP-ribosylation is a common post-translational modification of proteins; also nucleic acids and small molecules can be modified by the covalent attachment of ADP-ribose. This modification, important in cellular signalling and infection processes, is usually executed by enzymes from the large superfamily of ADP-ribosyltransferases (ARTs). Here, using bioinformatics approaches, we identify a novel putative ADP-ribosyltransferase family, conserved in eukaryotic evolution, with a divergent active site. The hallmark of these proteins is the ART domain nestled between flanking leucine-rich repeat (LRR) domains. LRRs are typically involved in innate immune surveillance. The novel family appears as putative novel ADP-ribosylation-related actors, most likely pseudoenzymes. Sequence divergence and lack of clearly detectable “classical” ART active site suggests the novel domains are pseudoARTs, yet atypical ART activity, or alternative enzymatic activity cannot be excluded. We propose that this family, including its human member LRRC9, may be involved in an ancient defense mechanism, with analogies to the innate immune system, and coupling pathogen detection to ADP-ribosyltransfer or other signalling mechanisms.
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Affiliation(s)
- Zbigniew Wyżewski
- Institute of Biological Sciences, Cardinal Stefan Wyszynski University in Warsaw, Warszawa, Poland
| | - Marcin Gradowski
- Department of Biochemistry and Microbiology, Warsaw University of Life Sciences - SGGW, Warszawa, Poland
| | - Marianna Krysińska
- Department of Biochemistry and Microbiology, Warsaw University of Life Sciences - SGGW, Warszawa, Poland
| | - Małgorzata Dudkiewicz
- Department of Biochemistry and Microbiology, Warsaw University of Life Sciences - SGGW, Warszawa, Poland
| | - Krzysztof Pawłowski
- Department of Biochemistry and Microbiology, Warsaw University of Life Sciences - SGGW, Warszawa, Poland.,Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, United States.,Department of Translational Medicine, Lund University, Lund, Sweden
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9
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Vatta M, Lyons B, Heney KA, Lidster T, Merrill AR. Mapping the DNA-Binding Motif of Scabin Toxin, a Guanine Modifying Enzyme from Streptomyces scabies. Toxins (Basel) 2021; 13:toxins13010055. [PMID: 33450958 PMCID: PMC7828395 DOI: 10.3390/toxins13010055] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 12/23/2020] [Accepted: 01/09/2021] [Indexed: 11/16/2022] Open
Abstract
Scabin is a mono-ADP-ribosyltransferase toxin/enzyme and possible virulence factor produced by the agriculture pathogen, Streptomyces scabies. Recently, molecular dynamic approaches and MD simulations revealed its interaction with both NAD+ and DNA substrates. An Essential Dynamics Analysis identified a crab-claw-like mechanism, including coupled changes in the exposed motifs, and the Rβ1-RLa-NLc-STTβ2-WPN-WARTT-(QxE)ARTT sequence motif was proposed as a catalytic signature of the Pierisin family of DNA-acting toxins. A new fluorescence assay was devised to measure the kinetics for both RNA and DNA substrates. Several protein variants were prepared to probe the Scabin-NAD-DNA molecular model and to reveal the reaction mechanism for the transfer of ADP-ribose to the guanine base in the DNA substrate. The results revealed that there are several lysine and arginine residues in Scabin that are important for binding the DNA substrate; also, key residues such as Asn110 in the mechanism of ADP-ribose transfer to the guanine base were identified. The DNA-binding residues are shared with ScARP from Streptomyces coelicolor but are not conserved with Pierisin-1, suggesting that the modification of guanine bases by ADP-ribosyltransferases is divergent even in the Pierisin family.
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Affiliation(s)
- Maritza Vatta
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada;
| | - Bronwyn Lyons
- Department of Biochemistry and Molecular Biology and Center for Blood Research, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3, Canada;
| | - Kayla A. Heney
- Department of Biochemistry, McGill University, Montreal, QC H3G 1Y6, Canada;
| | - Taylor Lidster
- Department of Biological Sciences, Brock University, St. Catherines, ON L2S 3A1, Canada;
| | - A. Rod Merrill
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada;
- Correspondence: ; Fax: +1-519-837-1802
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10
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Lugo MR, Merrill AR. Development of Anti-Virulence Therapeutics against Mono-ADP-Ribosyltransferase Toxins. Toxins (Basel) 2020; 13:toxins13010016. [PMID: 33375750 PMCID: PMC7824265 DOI: 10.3390/toxins13010016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/16/2020] [Accepted: 12/23/2020] [Indexed: 12/27/2022] Open
Abstract
Mono-ADP-ribosyltransferase toxins are often key virulence factors produced by pathogenic bacteria as tools to compromise the target host cell. These toxins are enzymes that use host cellular NAD+ as the substrate to modify a critical macromolecule target in the host cell machinery. This post-translational modification of the target macromolecule (usually protein or DNA) acts like a switch to turn the target activity on or off resulting in impairment of a critical process or pathway in the host. One approach to stymie bacterial pathogens is to curtail the toxic action of these factors by designing small molecules that bind tightly to the enzyme active site and prevent catalytic function. The inactivation of these toxins/enzymes is targeted for the site of action within the host cell and small molecule therapeutics can function as anti-virulence agents by disarming the pathogen. This represents an alternative strategy to antibiotic therapy with the potential as a paradigm shift that may circumvent multi-drug resistance in the offending microbe. In this review, work that has been accomplished during the past two decades on this approach to develop anti-virulence compounds against mono-ADP-ribosyltransferase toxins will be discussed.
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11
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Yoshida T, Tsuge H. Substrate N 2 atom recognition mechanism in pierisin family DNA-targeting, guanine-specific ADP-ribosyltransferase ScARP. J Biol Chem 2018; 293:13768-13774. [PMID: 30072382 DOI: 10.1074/jbc.ac118.004412] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 07/26/2018] [Indexed: 11/06/2022] Open
Abstract
ScARP from the bacterium Streptomyces coelicolor belongs to the pierisin family of DNA-targeting ADP-ribosyltransferases (ARTs). These enzymes ADP-ribosylate the N2 amino groups of guanine residues in DNA to yield N2-(ADP-ribos-1-yl)-2'-deoxyguanosine. Although the structures of pierisin-1 and Scabin were revealed recently, the substrate recognition mechanisms remain poorly understood because of the lack of a substrate-binding structure. Here, we report the apo structure of ScARP and of ScARP bound to NADH and its GDP substrate at 1.50 and 1.57 Å resolutions, respectively. The bound structure revealed that the guanine of GDP is trapped between N-ribose of NADH and Trp-159. Interestingly, N2 and N3 of guanine formed hydrogen bonds with the OE1 and NE2 atoms of Gln-162, respectively. We directly observed that the ADP-ribosylating toxin turn-turn (ARTT)-loop, including Trp-159 and Gln-162, plays a key role in the specificity of DNA-targeting, guanine-specific ARTs as well as protein-targeting ARTs such as the C3 exoenzyme. We propose that the ARTT-loop recognition is a common substrate-recognition mechanism in the pierisin family. Furthermore, this complex structure sheds light on similarities and differences among two subclasses that are distinguished by conserved structural motifs: H-Y-E in the ARTD subfamily and R-S-E in the ARTC subfamily. The spatial arrangements of the electrophile and nucleophile were the same, providing the first evidence for a common reaction mechanism in these ARTs. ARTC (including ScARP) uses the ARTT-loop for substrate recognition, whereas ARTD (represented by Arr) uses the C-terminal helix instead of the ARTT-loop. These observations could help inform efforts to improve ART inhibitors.
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Affiliation(s)
- Toru Yoshida
- From the Department of Bioresource and Environmental Sciences, Faculty of Life Sciences.,Institute for Protein Dynamics, and
| | - Hideaki Tsuge
- From the Department of Bioresource and Environmental Sciences, Faculty of Life Sciences, .,Institute for Protein Dynamics, and.,Center for Molecular Research in Infectious Diseases, Kyoto Sangyo University, Kyoto 603-8555, Japan
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12
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Lugo MR, Lyons B, Lento C, Wilson DJ, Merrill AR. Dynamics of Scabin toxin. A proposal for the binding mode of the DNA substrate. PLoS One 2018; 13:e0194425. [PMID: 29543870 PMCID: PMC5854381 DOI: 10.1371/journal.pone.0194425] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 03/04/2018] [Indexed: 12/29/2022] Open
Abstract
Scabin is a mono-ADP-ribosyltransferase enzyme and is a putative virulence factor produced by the plant pathogen, Streptomyces scabies. Previously, crystal structures of Scabin were solved in the presence and absence of substrate analogues and inhibitors. Herein, experimental (hydrogen-deuterium exchange), simulated (molecular dynamics), and theoretical (Gaussian Network Modeling) approaches were systematically applied to study the dynamics of apo-Scabin in the context of a Scabin·NAD+·DNA model. MD simulations revealed that the apo-Scabin solution conformation correlates well with the X-ray crystal structure, beyond the conformation of the exposed, mobile regions. In turn, the MD fluctuations correspond with the crystallographic B-factors, with the fluctuations derived from a Gaussian network model, and with the experimental H/D exchange rates. An Essential Dynamics Analysis identified the dynamic aspects of the toxin as a crab-claw-like mechanism of two topological domains, along with coupled deformations of exposed motifs. The “crab-claw” movement resembles the motion of C3-like toxins and emerges as a property of the central β scaffold of catalytic single domain toxins. The exposure and high mobility of the cis side motifs in the Scabin β-core suggest involvement in DNA substrate binding. A ternary Scabin·NAD+·DNA model was produced via an independent docking methodology, where the intermolecular interactions correspond to the region of high mobility identified by dynamics analyses and agree with binding and kinetic data reported for wild-type and Scabin variants. Based on data for the Pierisin-like toxin group, the sequence motif Rβ1–RLa–NLc–STTβ2–WPN–WARTT–(QxE)ARTT emerges as a catalytic signature involved in the enzymatic activity of these DNA-acting toxins. However, these results also show that Scabin possesses a unique DNA-binding motif within the Pierisin-like toxin group.
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Affiliation(s)
- Miguel R Lugo
- Department of Molecular and Cell Biology, University of Guelph, Guelph, Ontario, Canada
| | - Bronwyn Lyons
- Department of Molecular and Cell Biology, University of Guelph, Guelph, Ontario, Canada.,Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Cristina Lento
- Chemistry Department, York University, Toronto, Ontario, Canada.,The Centre for Research in Mass Spectrometry, York University, Toronto, Ontario, Canada
| | - Derek J Wilson
- Chemistry Department, York University, Toronto, Ontario, Canada.,The Centre for Research in Mass Spectrometry, York University, Toronto, Ontario, Canada
| | - A Rod Merrill
- Department of Molecular and Cell Biology, University of Guelph, Guelph, Ontario, Canada
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