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Tessmer I, Margison GP. The DNA Alkyltransferase Family of DNA Repair Proteins: Common Mechanisms, Diverse Functions. Int J Mol Sci 2023; 25:463. [PMID: 38203633 PMCID: PMC10779285 DOI: 10.3390/ijms25010463] [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: 11/30/2023] [Revised: 12/22/2023] [Accepted: 12/27/2023] [Indexed: 01/12/2024] Open
Abstract
DNA alkyltransferase and alkyltransferase-like family proteins are responsible for the repair of highly mutagenic and cytotoxic O6-alkylguanine and O4-alkylthymine bases in DNA. Their mechanism involves binding to the damaged DNA and flipping the base out of the DNA helix into the active site pocket in the protein. Alkyltransferases then directly and irreversibly transfer the alkyl group from the base to the active site cysteine residue. In contrast, alkyltransferase-like proteins recruit nucleotide excision repair components for O6-alkylguanine elimination. One or more of these proteins are found in all kingdoms of life, and where this has been determined, their overall DNA repair mechanism is strictly conserved between organisms. Nevertheless, between species, subtle as well as more extensive differences that affect target lesion preferences and/or introduce additional protein functions have evolved. Examining these differences and their functional consequences is intricately entwined with understanding the details of their DNA repair mechanism(s) and their biological roles. In this review, we will present and discuss various aspects of the current status of knowledge on this intriguing protein family.
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Affiliation(s)
- Ingrid Tessmer
- Rudolf Virchow Center, University of Würzburg, Josef-Schneider-Strasse 2, 97080 Würzburg, Germany
| | - Geoffrey P. Margison
- School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, UK;
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2
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Yin Y, Zhang L. Archaeal DNA alkylation repair conducted by DNA glycosylase and methyltransferase. Appl Microbiol Biotechnol 2023; 107:3131-3142. [PMID: 37036526 DOI: 10.1007/s00253-023-12506-3] [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: 02/17/2023] [Revised: 03/25/2023] [Accepted: 03/28/2023] [Indexed: 04/11/2023]
Abstract
Alkylated bases in DNA created in the presence of endogenous and exogenous alkylating agents are either cytotoxic or mutagenic, or both to a cell. Currently, cells have evolved several strategies for repairing alkylated base. One strategy is a base excision repair process triggered by a specific DNA glycosylase that is used for the repair of the cytotoxic 3-methyladenine. Additionally, the cytotoxic and mutagenic O6-methylguanine (O6-meG) is corrected by O6-methylguanine methyltransferase (MGMT) via directly transferring the methyl group in the lesion to a specific cysteine in this protein. Furthermore, oxidative DNA demethylation catalyzed by DNA dioxygenase is utilized for repairing the cytotoxic 3-methylcytosine (3-meC) and 1-methyladenine (1-meA) in a direct reversal manner. As the third domain of life, Archaea possess 3-methyladenine DNA glycosylase II (AlkA) and MGMT, but no DNA dioxygenase homologue responsible for oxidative demethylation. Herein, we summarize recent progress in structural and biochemical properties of archaeal AlkA and MGMT to gain a better understanding of archaeal DNA alkylation repair, focusing on similarities and differences between the proteins from different archaeal species and between these archaeal proteins and their bacterial and eukaryotic relatives. To our knowledge, it is the first review on archaeal DNA alkylation repair conducted by DNA glycosylase and methyltransferase. KEY POINTS: • Archaeal MGMT plays an essential role in the repair of O 6 -meG • Archaeal AlkA can repair 3-meC and 1-meA.
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Affiliation(s)
- Youcheng Yin
- Marine Science & Technology Institute, College of Environmental Science and Engineering, Yangzhou University, Yangzhou City, China
| | - Likui Zhang
- Marine Science & Technology Institute, College of Environmental Science and Engineering, Yangzhou University, Yangzhou City, China.
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3
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Mattossovich R, Merlo R, Miggiano R, Valenti A, Perugino G. O6-alkylguanine-DNA Alkyltransferases in Microbes Living on the Edge: From Stability to Applicability. Int J Mol Sci 2020; 21:E2878. [PMID: 32326075 PMCID: PMC7216122 DOI: 10.3390/ijms21082878] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 04/09/2020] [Accepted: 04/16/2020] [Indexed: 02/06/2023] Open
Abstract
The genome of living cells is continuously exposed to endogenous and exogenous attacks, and this is particularly amplified at high temperatures. Alkylating agents cause DNA damage, leading to mutations and cell death; for this reason, they also play a central role in chemotherapy treatments. A class of enzymes known as AGTs (alkylguanine-DNA-alkyltransferases) protects the DNA from mutations caused by alkylating agents, in particular in the recognition and repair of alkylated guanines in O6-position. The peculiar irreversible self-alkylation reaction of these enzymes triggered numerous studies, especially on the human homologue, in order to identify effective inhibitors in the fight against cancer. In modern biotechnology, engineered variants of AGTs are developed to be used as protein tags for the attachment of chemical ligands. In the last decade, research on AGTs from (hyper)thermophilic sources proved useful as a model system to clarify numerous phenomena, also common for mesophilic enzymes. This review traces recent progress in this class of thermozymes, emphasizing their usefulness in basic research and their consequent advantages for in vivo and in vitro biotechnological applications.
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Affiliation(s)
- Rosanna Mattossovich
- Institute of Bioscience and BioResources, National Research Council of Italy, Via Pietro Castellino 111, 80131 Naples, Italy; (R.M.); (R.M.)
| | - Rosa Merlo
- Institute of Bioscience and BioResources, National Research Council of Italy, Via Pietro Castellino 111, 80131 Naples, Italy; (R.M.); (R.M.)
| | - Riccardo Miggiano
- Department of Pharmaceutical Sciences, University of Piemonte Orientale, Via Bovio 6, 28100 Novara, Italy;
| | - Anna Valenti
- Institute of Bioscience and BioResources, National Research Council of Italy, Via Pietro Castellino 111, 80131 Naples, Italy; (R.M.); (R.M.)
| | - Giuseppe Perugino
- Institute of Bioscience and BioResources, National Research Council of Italy, Via Pietro Castellino 111, 80131 Naples, Italy; (R.M.); (R.M.)
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4
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Mattossovich R, Merlo R, Fontana A, d'Ippolito G, Terns MP, Watts EA, Valenti A, Perugino G. A journey down to hell: new thermostable protein-tags for biotechnology at high temperatures. Extremophiles 2019; 24:81-91. [PMID: 31555904 DOI: 10.1007/s00792-019-01134-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 09/13/2019] [Indexed: 12/14/2022]
Abstract
The specific labelling of proteins in recent years has made use of self-labelling proteins, such as the SNAP-tag® and the Halotag®. These enzymes, by their nature or suitably engineered, have the ability to specifically react with their respective substrates, but covalently retaining a part of them in the catalytic site upon reaction. This led to the synthesis of substrates conjugated with, e.g., fluorophores (proposing them as alternatives to fluorescent proteins), but also with others chemical groups, for numerous biotechnological applications. Recently, a mutant of the OGT from Saccharolobus solfataricus (H5) very stable to high temperatures and in the presence of physical and chemical denaturing agents has been proposed as a thermostable SNAP-tag® for in vivo and in vitro harsh reaction conditions. Here, we show two new thermostable OGTs from Thermotoga neapolitana and Pyrococcus furiosus, which, respectively, display a higher catalytic activity and thermostability respect to H5, proposing them as alternatives for in vivo studies in these extreme model organisms.
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Affiliation(s)
- Rosanna Mattossovich
- Institute of Biosciences and BioResources, National Council of Research of Italy, Via P. Castellino 111, 80131, Naples, Italy
| | - Rosa Merlo
- Institute of Biosciences and BioResources, National Council of Research of Italy, Via P. Castellino 111, 80131, Naples, Italy
| | - Angelo Fontana
- Institute of Biomolecular Chemistry, National Council of Research of Italy, Via Campi Flegrei, 34, 80078, Pozzuoli, NA, Italy
| | - Giuliana d'Ippolito
- Institute of Biomolecular Chemistry, National Council of Research of Italy, Via Campi Flegrei, 34, 80078, Pozzuoli, NA, Italy
| | - Michael P Terns
- Departments of Biochemistry and Molecular Biology, Genetics, and Microbiology, University of Georgia, Athens, GA, USA
| | - Elizabeth A Watts
- Departments of Biochemistry and Molecular Biology, Genetics, and Microbiology, University of Georgia, Athens, GA, USA
| | - Anna Valenti
- Institute of Biosciences and BioResources, National Council of Research of Italy, Via P. Castellino 111, 80131, Naples, Italy
| | - Giuseppe Perugino
- Institute of Biosciences and BioResources, National Council of Research of Italy, Via P. Castellino 111, 80131, Naples, Italy.
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Miggiano R, Valenti A, Rossi F, Rizzi M, Perugino G, Ciaramella M. Every OGT Is Illuminated … by Fluorescent and Synchrotron Lights. Int J Mol Sci 2017; 18:ijms18122613. [PMID: 29206193 PMCID: PMC5751216 DOI: 10.3390/ijms18122613] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 11/28/2017] [Accepted: 11/30/2017] [Indexed: 12/23/2022] Open
Abstract
O6-DNA-alkyl-guanine-DNA-alkyl-transferases (OGTs) are evolutionarily conserved, unique proteins that repair alkylation lesions in DNA in a single step reaction. Alkylating agents are environmental pollutants as well as by-products of cellular reactions, but are also very effective chemotherapeutic drugs. OGTs are major players in counteracting the effects of such agents, thus their action in turn affects genome integrity, survival of organisms under challenging conditions and response to chemotherapy. Numerous studies on OGTs from eukaryotes, bacteria and archaea have been reported, highlighting amazing features that make OGTs unique proteins in their reaction mechanism as well as post-reaction fate. This review reports recent functional and structural data on two prokaryotic OGTs, from the pathogenic bacterium Mycobacterium tuberculosis and the hyperthermophilic archaeon Sulfolobus solfataricus, respectively. These studies provided insight in the role of OGTs in the biology of these microorganisms, but also important hints useful to understand the general properties of this class of proteins.
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Affiliation(s)
- Riccardo Miggiano
- DSF-Dipartimento di Scienze del Farmaco, University of Piemonte Orientale, Via Bovio 6, 28100 Novara, Italy.
| | - Anna Valenti
- Institute of Biosciences and BioResources, National Research Council of Italy, Via Pietro Castellino 111, 80131 Naples, Italy.
| | - Franca Rossi
- DSF-Dipartimento di Scienze del Farmaco, University of Piemonte Orientale, Via Bovio 6, 28100 Novara, Italy.
| | - Menico Rizzi
- DSF-Dipartimento di Scienze del Farmaco, University of Piemonte Orientale, Via Bovio 6, 28100 Novara, Italy.
| | - Giuseppe Perugino
- Institute of Biosciences and BioResources, National Research Council of Italy, Via Pietro Castellino 111, 80131 Naples, Italy.
| | - Maria Ciaramella
- Institute of Biosciences and BioResources, National Research Council of Italy, Via Pietro Castellino 111, 80131 Naples, Italy.
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Genome stability: recent insights in the topoisomerase reverse gyrase and thermophilic DNA alkyltransferase. Extremophiles 2014; 18:895-904. [DOI: 10.1007/s00792-014-0662-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Accepted: 05/18/2014] [Indexed: 10/24/2022]
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Stefanska A, Kaczorowska AK, Plotka M, Fridjonsson OH, Hreggvidsson GO, Hjorleifsdottir S, Kristjansson JK, Dabrowski S, Kaczorowski T. Discovery and characterization of RecA protein of thermophilic bacterium Thermus thermophilus MAT72 phage Tt72 that increases specificity of a PCR-based DNA amplification. J Biotechnol 2014; 182-183:1-10. [PMID: 24786823 DOI: 10.1016/j.jbiotec.2014.04.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Revised: 03/21/2014] [Accepted: 04/15/2014] [Indexed: 10/25/2022]
Abstract
The recA gene of newly discovered Thermus thermophilus MAT72 phage Tt72 (Myoviridae) was cloned and overexpressed in Escherichia coli. The 1020-bp gene codes for a 339-amino-acid polypeptide with an Mr of 38,155 which shows 38.7% positional identity to the E. coli RecA protein. When expressed in E. coli, the Tt72 recA gene did not confer the ability to complement the ultraviolet light (254nm) sensitivity of an E. coli recA mutant. Tt72 RecA protein has been purified with good yield to catalytic and electrophoretic homogeneity using a three-step chromatography procedure. Biochemical characterization indicated that the protein can pair and promote ATP-dependent strand exchange reaction resulting in formation of a heteroduplex DNA at 60°C under conditions otherwise optimal for E. coli RecA. When the Tt72 RecA protein was included in a standard PCR-based DNA amplification reaction, the specificity of the PCR assays was significantly improved by eliminating non-specific products.
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Affiliation(s)
- Aleksandra Stefanska
- Department of Microbiology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland.
| | - Anna-Karina Kaczorowska
- Collection of Plasmids and Microorganisms, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland.
| | - Magdalena Plotka
- Department of Microbiology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland.
| | | | - Gudmundur O Hreggvidsson
- Matis ohf, Vinlandsleid 12, Reykjavik 113, Iceland; Faculty of Life and Environmental Sciences, University of Iceland, Sæmundargötu 2, Reykjavik 101, Iceland.
| | | | | | | | - Tadeusz Kaczorowski
- Department of Microbiology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland.
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Roberts A, Pelton JG, Wemmer DE. Structural studies of MJ1529, an O6-methylguanine-DNA methyltransferase. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2006; 44 Spec No:S71-82. [PMID: 16826543 DOI: 10.1002/mrc.1823] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The structure of an O6-methylguanine-DNA methyltransferase (MGMT) from the thermophile Methanococcus jannaschii has been determined using multinuclear multidimensional NMR spectroscopy. The structure is similar to homologs from other organisms that have been determined by crystallography, with some variation in the N-terminal domain. The C-terminal domain is more highly conserved in both sequence and structure. Regions of the protein show broadening, reflecting conformational flexibility that is likely related to function.
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Affiliation(s)
- Anne Roberts
- Department of Chemistry, University of California and Physical Biosciences Division, Lawrence Berkeley National Lab, Berkeley, CA 94720-1460, USA
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Kanugula S, Pegg AE. Alkylation damage repair protein O6-alkylguanine-DNA alkyltransferase from the hyperthermophiles Aquifex aeolicus and Archaeoglobus fulgidus. Biochem J 2003; 375:449-55. [PMID: 12892560 PMCID: PMC1223701 DOI: 10.1042/bj20030809] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2003] [Revised: 07/24/2003] [Accepted: 08/01/2003] [Indexed: 10/27/2022]
Abstract
AGT (O6-alkylguanine DNA alkyltransferase) is an important DNA-repair protein that protects cells from killing and mutagenesis by alkylating agents. The AGT genes from two extremely thermophilic organisms, the bacterium Aquifex aeolicus and the archaeon Archaeoglobus fulgidus were PCR-derived and cloned into an expression vector. The nucleotide sequence of the Aq. aeolicus AGT encodes a 201-amino-acid protein with a molecular mass of 23000 Da and Ar. fulgidus AGT codes for a 147-amino-acid protein with a molecular mass of 16718 Da. The Aq. aeolicus and Ar. fulgidus AGTs were expressed at high levels in Escherichia coli fused to an N-terminal polyhistidine tag that allowed single-step isolation and purification by metal-affinity chromatography. Both AGTs formed inclusion bodies and were not soluble under native purification conditions. Therefore AGT isolation was performed under protein-denaturation conditions in the presence of 8.0 M urea. Soluble AGT was obtained by refolding the AGT in the presence of calf thymus DNA. Both AGTs were active in repairing O6-methylguanine and, at a lower rate, O4-methylthymine in DNA. They exhibited thermostability and optimum activity at high temperature. The thermostable AGTs, particularly that from Aq. aeolicus, were readily inactivated by the low-molecular-mass inhibitor O6-benzylguanine, which is currently in clinical trials to enhance cancer chemotherapy.
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Affiliation(s)
- Sreenivas Kanugula
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, The Milton S. Hershey Medical Center, P.O. Box 850, 500 University Drive, Hershey, PA 17033, USA
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Sartori AA, Jiricny J. Enzymology of base excision repair in the hyperthermophilic archaeon Pyrobaculum aerophilum. J Biol Chem 2003; 278:24563-76. [PMID: 12730226 DOI: 10.1074/jbc.m302397200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
DNA of all living organisms is constantly modified by exogenous and endogenous reagents. The mutagenic threat of modifications such as methylation, oxidation, and hydrolytic deamination of DNA bases is counteracted by base excision repair (BER). This process is initiated by the action of one of several DNA glycosylases, which removes the aberrant base and thus initiates a cascade of events that involves scission of the DNA backbone, removal of the baseless sugar-phosphate residue, filling in of the resulting single nucleotide gap, and ligation of the remaining nick. We were interested to find out how the BER process functions in hyperthermophiles, organisms growing at temperatures around 100 degrees C, where the rates of these spontaneous reactions are greatly accelerated. In our previous studies, we could show that the crenarchaeon Pyrobaculum aerophilum has at least three uracil-DNA glycosylases, Pa-UDGa, Pa-UDGb, and Pa-MIG, that can initiate the BER process by catalyzing the removal of uracil residues arising through the spontaneous deamination of cytosines. We now report that the genome of P. aerophilum encodes also the remaining functions necessary for BER and show that a system consisting of four P. aerophilum encoded enzymes, Pa-UDGb, AP endonuclease IV, DNA polymerase B2, and DNA ligase, can efficiently repair a G.U mispair in an oligonucleotide substrate to a G.C pair. Interestingly, the efficiency of the in vitro repair reaction was stimulated by Pa-PCNA1, the processivity clamp of DNA polymerases.
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Affiliation(s)
- Alessandro A Sartori
- Institute of Molecular Cancer Research, University of Zürich, August Forel-Strasse 7, Switzerland
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Makarova KS, Aravind L, Grishin NV, Rogozin IB, Koonin EV. A DNA repair system specific for thermophilic Archaea and bacteria predicted by genomic context analysis. Nucleic Acids Res 2002; 30:482-96. [PMID: 11788711 PMCID: PMC99818 DOI: 10.1093/nar/30.2.482] [Citation(s) in RCA: 248] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
During a systematic analysis of conserved gene context in prokaryotic genomes, a previously undetected, complex, partially conserved neighborhood consisting of more than 20 genes was discovered in most Archaea (with the exception of Thermoplasma acidophilum and Halobacterium NRC-1) and some bacteria, including the hyperthermophiles Thermotoga maritima and Aquifex aeolicus. The gene composition and gene order in this neighborhood vary greatly between species, but all versions have a stable, conserved core that consists of five genes. One of the core genes encodes a predicted DNA helicase, often fused to a predicted HD-superfamily hydrolase, and another encodes a RecB family exonuclease; three core genes remain uncharacterized, but one of these might encode a nuclease of a new family. Two more genes that belong to this neighborhood and are present in most of the genomes in which the neighborhood was detected encode, respectively, a predicted HD-superfamily hydrolase (possibly a nuclease) of a distinct family and a predicted, novel DNA polymerase. Another characteristic feature of this neighborhood is the expansion of a superfamily of paralogous, uncharacterized proteins, which are encoded by at least 20-30% of the genes in the neighborhood. The functional features of the proteins encoded in this neighborhood suggest that they comprise a previously undetected DNA repair system, which, to our knowledge, is the first repair system largely specific for thermophiles to be identified. This hypothetical repair system might be functionally analogous to the bacterial-eukaryotic system of translesion, mutagenic repair whose central components are DNA polymerases of the UmuC-DinB-Rad30-Rev1 superfamily, which typically are missing in thermophiles.
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MESH Headings
- Amino Acid Sequence
- Archaea/enzymology
- Archaea/genetics
- Bacteria/enzymology
- Bacteria/genetics
- Conserved Sequence/genetics
- DNA Helicases/genetics
- DNA Repair/genetics
- DNA-Directed DNA Polymerase/chemistry
- DNA-Directed DNA Polymerase/genetics
- Databases, Nucleic Acid
- Evolution, Molecular
- Exonucleases/chemistry
- Exonucleases/genetics
- Gene Order/genetics
- Gene Transfer, Horizontal
- Genes, Archaeal/genetics
- Genes, Bacterial/genetics
- Genome, Archaeal
- Genome, Bacterial
- Hydrolases/genetics
- Models, Molecular
- Molecular Sequence Data
- Operon/genetics
- Phylogeny
- Protein Structure, Secondary
- Protein Structure, Tertiary
- Sequence Alignment
- Species Specificity
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Affiliation(s)
- Kira S Makarova
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Building 380, Bethesda, MD 20894, USA
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Raychaudhuri S, Karmakar P, Thakur AR. γ -Ray-Induced DNA Damage and Repair in Methanosarcina barkeri. Anaerobe 2000. [DOI: 10.1006/anae.2000.0359] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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13
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Abstract
Hyperthermophilic archaea grow at temperatures that destabilize the primary structure of DNA and in evolutionary terms they are highly divergent from other well studied microorganisms. These prokaryotes should therefore require DNA damage repair to be unusually effective, and could employ novel mechanisms for this repair. Recent genome sequence analyses and biochemical and genetic assays suggest a distribution of DNA repair strategies that raises intriguing questions for future study.
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Affiliation(s)
- D W Grogan
- Dept of Biological Sciences, University of Cincinnati, PO Box 210006, Cincinnati OH 45221-0006, USA.
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14
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Abstract
The ability to recognize and repair abnormal DNA structures is common to all forms of life. Studies in a variety of species have identified an incredible diversity of DNA repair pathways. Documenting and characterizing the similarities and differences in repair between species has important value for understanding the origin and evolution of repair pathways as well as for improving our understanding of phenotypes affected by repair (e.g., mutation rates, lifespan, tumorigenesis, survival in extreme environments). Unfortunately, while repair processes have been studied in quite a few species, the ecological and evolutionary diversity of such studies has been limited. Complete genome sequences can provide potential sources of new information about repair in different species. In this paper, we present a global comparative analysis of DNA repair proteins and processes based upon the analysis of available complete genome sequences. We use a new form of analysis that combines genome sequence information and phylogenetic studies into a composite analysis we refer to as phylogenomics. We use this phylogenomic analysis to study the evolution of repair proteins and processes and to predict the repair phenotypes of those species for which we now know the complete genome sequence.
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Affiliation(s)
- J A Eisen
- Department of Biological Sciences, Stanford University, Stanford, CA 94305-5020, USA.
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