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Ahlqvist J, Linares-Pastén JA, Håkansson M, Jasilionis A, Kwiatkowska-Semrau K, Friðjónsson ÓH, Kaczorowska AK, Dabrowski S, Ævarsson A, Hreggviðsson GÓ, Al-Karadaghi S, Kaczorowski T, Nordberg Karlsson E. Crystal structure and initial characterization of a novel archaeal-like Holliday junction-resolving enzyme from Thermus thermophilus phage Tth15-6. Acta Crystallogr D Struct Biol 2022; 78:212-227. [PMID: 35102887 PMCID: PMC8805305 DOI: 10.1107/s2059798321012298] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 11/19/2021] [Indexed: 11/10/2022] Open
Abstract
This study describes the production, characterization and structure determination of a novel Holliday junction-resolving enzyme. The enzyme, termed Hjc_15-6, is encoded in the genome of phage Tth15-6, which infects Thermus thermophilus. Hjc_15-6 was heterologously produced in Escherichia coli and high yields of soluble and biologically active recombinant enzyme were obtained in both complex and defined media. Amino-acid sequence and structure comparison suggested that the enzyme belongs to a group of enzymes classified as archaeal Holliday junction-resolving enzymes, which are typically divalent metal ion-binding dimers that are able to cleave X-shaped dsDNA–Holliday junctions (Hjs). The crystal structure of Hjc_15-6 was determined to 2.5 Å resolution using the selenomethionine single-wavelength anomalous dispersion method. To our knowledge, this is the first crystal structure of an Hj-resolving enzyme originating from a bacteriophage that can be classified as an archaeal type of Hj-resolving enzyme. As such, it represents a new fold for Hj-resolving enzymes from phages. Characterization of the structure of Hjc_15-6 suggests that it may form a dimer, or even a homodimer of dimers, and activity studies show endonuclease activity towards Hjs. Furthermore, based on sequence analysis it is proposed that Hjc_15-6 has a three-part catalytic motif corresponding to E–SD–EVK, and this motif may be common among other Hj-resolving enzymes originating from thermophilic bacteriophages.
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2
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Ishino Y. Studies on DNA-related enzymes to elucidate molecular mechanisms underlying genetic information processing and their application in genetic engineering. Biosci Biotechnol Biochem 2020; 84:1749-1766. [PMID: 32567488 DOI: 10.1080/09168451.2020.1778441] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Recombinant DNA technology, in which artificially "cut and pasted" DNA in vitro is introduced into living cells, contributed extensively to the rapid development of molecular biology over the past 5 decades since the latter half of the 20th century. Although the original technology required special experiences and skills, the development of polymerase chain reaction (PCR) has greatly eased in vitro genetic manipulation for various experimental methods. The current development of a simple genome-editing technique using CRISPR-Cas9 gave great impetus to molecular biology. Genome editing is a major technique for elucidating the functions of many unknown genes. Genetic manipulation technologies rely on enzymes that act on DNA. It involves artificially synthesizing, cleaving, and ligating DNA strands by making good use of DNA-related enzymes present in organisms to maintain their life activities. In this review, I focus on key enzymes involved in the development of genetic manipulation technologies.
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Affiliation(s)
- Yoshizumi Ishino
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University , Fukuoka, Japan
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3
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Zhai B, DuPrez K, Doukov TI, Li H, Huang M, Shang G, Ni J, Gu L, Shen Y, Fan L. Structure and Function of a Novel ATPase that Interacts with Holliday Junction Resolvase Hjc and Promotes Branch Migration. J Mol Biol 2017; 429:1009-1029. [PMID: 28238763 PMCID: PMC5565510 DOI: 10.1016/j.jmb.2017.02.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 01/25/2017] [Accepted: 02/19/2017] [Indexed: 11/15/2022]
Abstract
Holliday junction (HJ) is a hallmark intermediate in DNA recombination and must be processed by dissolution (for double HJ) or resolution to ensure genome stability. Although HJ resolvases have been identified in all domains of life, there is a long-standing effort to search in prokaryotes and eukarya for proteins promoting HJ migration. Here, we report the structural and functional characterization of a novel ATPase, Sulfolobus islandicusPilT N-terminal-domain-containing ATPase (SisPINA), encoded by the gene adjacent to the resolvase Hjc coding gene. PINA is conserved in archaea and vital for S. islandicus viability. Purified SisPINA forms hexameric rings in the crystalline state and in solution, similar to the HJ migration helicase RuvB in Gram-negative bacteria. Structural analysis suggests that ATP binding and hydrolysis cause conformational changes in SisPINA to drive branch migration. Further studies reveal that SisPINA interacts with SisHjc and coordinates HJ migration and cleavage.
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Affiliation(s)
- Binyuan Zhai
- State Key Laboratory of Microbial Technology, Shandong University, 27 Shanda Nan Road, Jinan 250100, PR China
| | - Kevin DuPrez
- Department of Biochemistry, University of California, Riverside, CA 92521, USA
| | - Tzanko I Doukov
- Macromolecular Crystallography Group, Stanford Synchrotron Radiation Light Source, SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94309, USA
| | - Huan Li
- State Key Laboratory of Microbial Technology, Shandong University, 27 Shanda Nan Road, Jinan 250100, PR China
| | - Mengting Huang
- State Key Laboratory of Microbial Technology, Shandong University, 27 Shanda Nan Road, Jinan 250100, PR China
| | - Guijun Shang
- State Key Laboratory of Microbial Technology, Shandong University, 27 Shanda Nan Road, Jinan 250100, PR China
| | - Jinfeng Ni
- State Key Laboratory of Microbial Technology, Shandong University, 27 Shanda Nan Road, Jinan 250100, PR China
| | - Lichuan Gu
- State Key Laboratory of Microbial Technology, Shandong University, 27 Shanda Nan Road, Jinan 250100, PR China
| | - Yulong Shen
- State Key Laboratory of Microbial Technology, Shandong University, 27 Shanda Nan Road, Jinan 250100, PR China.
| | - Li Fan
- Department of Biochemistry, University of California, Riverside, CA 92521, USA.
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4
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Govindaraju A, Cortez JD, Reveal B, Christensen SM. Endonuclease domain of non-LTR retrotransposons: loss-of-function mutants and modeling of the R2Bm endonuclease. Nucleic Acids Res 2016; 44:3276-87. [PMID: 26961309 PMCID: PMC4838377 DOI: 10.1093/nar/gkw134] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 02/22/2016] [Accepted: 02/23/2016] [Indexed: 01/07/2023] Open
Abstract
Non-LTR retrotransposons are an important class of mobile elements that insert into host DNA by target-primed reverse transcription (TPRT). Non-LTR retrotransposons must bind to their mRNA, recognize and cleave their target DNA, and perform TPRT at the site of DNA cleavage. As DNA binding and cleavage are such central parts of the integration reaction, a better understanding of the endonuclease encoded by non-LTR retrotransposons is needed. This paper explores the R2 endonuclease domain from Bombyx mori using in vitro studies and in silico modeling. Mutations in conserved sequences located across the putative PD-(D/E)XK endonuclease domain reduced DNA cleavage, DNA binding and TPRT. A mutation at the beginning of the first α-helix of the modeled endonuclease obliterated DNA cleavage and greatly reduced DNA binding. It also reduced TPRT when tested on pre-cleaved DNA substrates. The catalytic K was located to a non-canonical position within the second α-helix. A mutation located after the fourth β-strand reduced DNA binding and cleavage. The motifs that showed impaired activity form an extensive basic region. The R2 biochemical and structural data are compared and contrasted with that of two other well characterized PD-(D/E)XK endonucleases, restriction endonucleases and archaeal Holliday junction resolvases.
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Affiliation(s)
- Aruna Govindaraju
- Department of Biology, University of Texas at Arlington, Arlington, TX 76019-0498, USA
| | - Jeremy D. Cortez
- Department of Biology, University of Texas at Arlington, Arlington, TX 76019-0498, USA
| | - Brad Reveal
- Department of Biology, University of Texas at Arlington, Arlington, TX 76019-0498, USA
| | - Shawn M. Christensen
- Department of Biology, University of Texas at Arlington, Arlington, TX 76019-0498, USA
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5
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Abstract
Four-way DNA intermediates, called Holliday junctions (HJs), can form during meiotic and mitotic recombination, and their removal is crucial for chromosome segregation. A group of ubiquitous and highly specialized structure-selective endonucleases catalyze the cleavage of HJs into two disconnected DNA duplexes in a reaction called HJ resolution. These enzymes, called HJ resolvases, have been identified in bacteria and their bacteriophages, archaea, and eukaryotes. In this review, we discuss fundamental aspects of the HJ structure and their interaction with junction-resolving enzymes. This is followed by a brief discussion of the eubacterial RuvABC enzymes, which provide the paradigm for HJ resolvases in other organisms. Finally, we review the biochemical and structural properties of some well-characterized resolvases from archaea, bacteriophage, and eukaryotes.
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Affiliation(s)
- Haley D M Wyatt
- London Research Institute, Cancer Research UK, Clare Hall Laboratories, South Mimms, Herts EN6 3LD, United Kingdom
| | - Stephen C West
- London Research Institute, Cancer Research UK, Clare Hall Laboratories, South Mimms, Herts EN6 3LD, United Kingdom
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Zhang Y, Lin J, Gao Y. In silico identification of a multi-functional regulatory protein involved in Holliday junction resolution in bacteria. BMC SYSTEMS BIOLOGY 2012; 6 Suppl 1:S20. [PMID: 23046553 PMCID: PMC3403352 DOI: 10.1186/1752-0509-6-s1-s20] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Homologous recombination is a fundamental cellular process that is most widely used by cells to rearrange genes and accurately repair DNA double-strand breaks. It may result in the formation of a critical intermediate named Holliday junction, which is a four-way DNA junction and needs to be resolved to allow chromosome segregation. Different Holliday junction resolution systems and enzymes have been characterized from all three domains of life. In bacteria, the RuvABC complex is the most important resolution system. RESULTS In this study, we conducted comparative genomics studies to identify a novel DNA-binding protein, YebC, which may serve as a key transcriptional regulator that mainly regulates the gene expression of RuvABC resolvasome in bacteria. On the other hand, the presence of YebC orthologs in some organisms lacking RuvC implied that it might participate in other biological processes. Further phylogenetic analysis of YebC protein sequences revealed two functionally different subtypes: YebC_I and YebC_II. Distribution of YebC_I is much wider than YebC_II. Only YebC_I proteins may play an important role in regulating RuvABC gene expression in bacteria. Investigation of YebC-like proteins in eukaryotes suggested that they may have originated from YebC_II proteins and evolved a new function as a specific translational activator in mitochondria. Finally, additional phylum-specific genes associated with Holliday junction resolution were predicted. CONCLUSIONS Overall, our data provide new insights into the basic mechanism of Holliday junction resolution and homologous recombination in bacteria.
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Affiliation(s)
- Yan Zhang
- Key Laboratory of Systems Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200031 China
| | - Jie Lin
- Key Laboratory of Systems Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200031 China
| | - Yang Gao
- Computer Network Information Center, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005 China
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Hjm/Hel308A DNA helicase from Sulfolobus tokodaii promotes replication fork regression and interacts with Hjc endonuclease in vitro. J Bacteriol 2008; 190:3006-17. [PMID: 18296528 DOI: 10.1128/jb.01662-07] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Hjm and Hel308a are novel, RecQ-like DNA helicases recently identified in the euryarchaeotes Pyrococcus furiosus and Methanothermobacter thermautotrophicus, respectively. In this study, an Hjm/Hel308 homologue (designated StoHjm) from Sulfolobus tokodaii, a hyperthermophilic archaeon belonging to the Crenarchaeota subdomain of archaea, was cloned, purified, and characterized. Unlike Hjm and Hel308a, which unwind DNA in a 3'-to-5' direction, StoHjm unwound DNA in both 3'-to-5' and 5'-to-3' directions. Remarkably, StoHjm exhibited structure-specific single-stranded-DNA-annealing and fork regression activities in vitro. In addition, gel filtration, affinity pulldown, and yeast two-hybrid analyses revealed that StoHjm physically interacted with StoHjc, the Holliday junction-specific endonuclease from S. tokodaii. This interaction may have functional significance, because the unwinding activity of StoHjm was inhibited by StoHjc in vitro. These results may suggest that the Hjm/Hel308 family helicases, in association with Hjc endonucleases, are involved in processing of stalled replication forks.
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Ishino Y, Nishino T, Morikawa K. Mechanisms of maintaining genetic stability by homologous recombination. Chem Rev 2006; 106:324-39. [PMID: 16464008 DOI: 10.1021/cr0404803] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yoshizumi Ishino
- Department of Genetic Resources Technology, Faculty of Agriculture, Kyushu University, Fukukoka-shi, Fukuoka, Japan.
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9
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Biertümpfel C, Basquin J, Birkenbihl RP, Suck D, Sauter C. Characterization of crystals of the Hjc resolvase from Archaeoglobus fulgidus grown in gel by counter-diffusion. Acta Crystallogr Sect F Struct Biol Cryst Commun 2005; 61:684-7. [PMID: 16511128 PMCID: PMC1952446 DOI: 10.1107/s1744309105018269] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2005] [Accepted: 06/09/2005] [Indexed: 11/10/2022]
Abstract
Holliday junction-resolving enzymes are ubiquitous proteins that play a key role in DNA repair and reorganization by homologous recombination. The Holliday junction-cutting enzyme (Hjc) from the archaeon Archaeoglobus fulgidus is a member of this group. The first Hjc crystals were obtained by conventional sparse-matrix screening. They exhibited an unusually elongated unit cell and their X-ray characterization required special care to avoid spot overlaps along the c* axis. The use of an arc appended to the goniometric head allowed proper orientation of plate-like crystals grown in agarose gel by counter-diffusion. Thus, complete diffraction data were collected at 2.7 A resolution using synchrotron radiation. They belong to space group P3(1)21 or P3(2)21, with unit-cell parameters a = b = 37.4, c = 271.8 A.
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Affiliation(s)
- Christian Biertümpfel
- European Molecular Biology Laboratory, Structural and Computational Biology Programme, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Jérôme Basquin
- European Molecular Biology Laboratory, Structural and Computational Biology Programme, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Rainer P. Birkenbihl
- European Molecular Biology Laboratory, Structural and Computational Biology Programme, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Dietrich Suck
- European Molecular Biology Laboratory, Structural and Computational Biology Programme, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Claude Sauter
- European Molecular Biology Laboratory, Structural and Computational Biology Programme, Meyerhofstrasse 1, 69117 Heidelberg, Germany
- Correspondence e-mail:
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10
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Rigden DJ. An inactivated nuclease-like domain in RecC with novel function: implications for evolution. BMC STRUCTURAL BIOLOGY 2005; 5:9. [PMID: 15985153 PMCID: PMC1185551 DOI: 10.1186/1472-6807-5-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2005] [Accepted: 06/28/2005] [Indexed: 02/03/2023]
Abstract
BACKGROUND The PD-(D/E)xK superfamily, containing a wide variety of other exo- and endonucleases, is a notable example of general function conservation in the face of extreme sequence and structural variation. Almost all members employ a small number of shared conserved residues to bind catalytically essential metal ions and thereby effect DNA cleavage. The crystal structure of the RecBCD prokaryotic DNA repair machinery shows that RecB contains such a nuclease domain at its C-terminus. The RecC C-terminal region was reported as having a novel fold. RESULTS The RecC C-terminal region can be divided into an alpha/beta domain and a smaller alpha-helical bundle domain. Here we show that the alpha/beta domain is homologous to the RecB nuclease domain but lacks the features necessary for catalysis. Instead, the domain has a novel function within the nuclease superfamily--providing a hoop through which single-stranded DNA passes. Comparison with other structures of nuclease domains bound to DNA reveals strikingly different modes of ligand binding. The alpha-helical bundle domain contributes the pin which splits the DNA duplex. CONCLUSION The demonstrated homology of RecB and RecC shows how evolution acted to produce the present RecBCD complex through aggregation of new domains as well as functional divergence and structural redeployment of existing domains. Distantly homologous nuclease(-like) domains bind DNA in highly diverse manners.
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Affiliation(s)
- Daniel John Rigden
- School of Biological Sciences, University of Liverpool, Crown St., Liverpool L69 7ZB, UK.
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11
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Feder M, Bujnicki JM. Identification of a new family of putative PD-(D/E)XK nucleases with unusual phylogenomic distribution and a new type of the active site. BMC Genomics 2005; 6:21. [PMID: 15720711 PMCID: PMC551604 DOI: 10.1186/1471-2164-6-21] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2004] [Accepted: 02/18/2005] [Indexed: 12/18/2022] Open
Abstract
Background Prediction of structure and function for uncharacterized protein families by identification of evolutionary links to characterized families and known structures is one of the cornerstones of genomics. Theoretical assignment of three-dimensional folds and prediction of protein function even at a very general level can facilitate the experimental determination of the molecular mechanism of action and the role that members of a given protein family fulfill in the cell. Here, we predict the three-dimensional fold and study the phylogenomic distribution of members of a large family of uncharacterized proteins classified in the Clusters of Orthologous Groups database as COG4636. Results Using protein fold-recognition we found that members of COG4636 are remotely related to Holliday junction resolvases and other nucleases from the PD-(D/E)XK superfamily. Structure modeling and sequence analyses suggest that most members of COG4636 exhibit a new, unusual variant of the putative active site, in which the catalytic Lys residue migrated in the sequence, but retained similar spatial position with respect to other functionally important residues. Sequence analyses revealed that members of COG4636 and their homologs are found mainly in Cyanobacteria, but also in other bacterial phyla. They undergo horizontal transfer and extensive proliferation in the colonized genomes; for instance in Gloeobacter violaceus PCC 7421 they comprise over 2% of all protein-encoding genes. Thus, members of COG4636 appear to be a new type of selfish genetic elements, which may fulfill an important role in the genome dynamics of Cyanobacteria and other species they invaded. Our analyses provide a platform for experimental determination of the molecular and cellular function of members of this large protein family. Conclusion After submission of this manuscript, a crystal structure of one of the COG4636 members was released in the Protein Data Bank (code 1wdj; Idaka, M., Wada, T., Murayama, K., Terada, T., Kuramitsu, S., Shirouzu, M., Yokoyama, S.: Crystal structure of Tt1808 from Thermus thermophilus Hb8, to be published). Our analysis of the Tt1808 structure reveals that we correctly predicted all functionally important features of the COG4636 family, including the membership in the PD-(D/E)xK superfamily of nucleases, the three-dimensional fold, the putative catalytic residues, and the unusual configuration of the active site.
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Affiliation(s)
- Marcin Feder
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology, Trojdena 4, 02-109 Warsaw, Poland
| | - Janusz M Bujnicki
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology, Trojdena 4, 02-109 Warsaw, Poland
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Middleton CL, Parker JL, Richard DJ, White MF, Bond CS. Substrate recognition and catalysis by the Holliday junction resolving enzyme Hje. Nucleic Acids Res 2004; 32:5442-51. [PMID: 15479781 PMCID: PMC524281 DOI: 10.1093/nar/gkh869] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Two archaeal Holliday junction resolving enzymes, Holliday junction cleavage (Hjc) and Holliday junction endonuclease (Hje), have been characterized. Both are members of a nuclease superfamily that includes the type II restriction enzymes, although their DNA cleaving activity is highly specific for four-way junction structure and not nucleic acid sequence. Despite 28% sequence identity, Hje and Hjc cleave junctions with distinct cutting patterns--they cut different strands of a four-way junction, at different distances from the junction centre. We report the high-resolution crystal structure of Hje from Sulfolobus solfataricus. The structure provides a basis to explain the differences in substrate specificity of Hje and Hjc, which result from changes in dimer organization, and suggests a viral origin for the Hje gene. Structural and biochemical data support the modelling of an Hje:DNA junction complex, highlighting a flexible loop that interacts intimately with the junction centre. A highly conserved serine residue on this loop is shown to be essential for the enzyme's activity, suggesting a novel variation of the nuclease active site. The loop may act as a conformational switch, ensuring that the active site is completed only on binding a four-way junction, thus explaining the exquisite specificity of these enzymes.
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Affiliation(s)
- Claire L Middleton
- Division of Biological Chemistry and Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
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Makarova KS, Koonin EV. Comparative genomics of Archaea: how much have we learned in six years, and what's next? Genome Biol 2003; 4:115. [PMID: 12914651 PMCID: PMC193635 DOI: 10.1186/gb-2003-4-8-115] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Archaea comprise one of the three distinct domains of life (with bacteria and eukaryotes). With 16 complete archaeal genomes sequenced to date, comparative genomics has revealed a conserved core of 313 genes that are represented in all sequenced archaeal genomes, plus a variable 'shell' that is prone to lineage-specific gene loss and horizontal gene exchange. The majority of archaeal genes have not been experimentally characterized, but novel functional pathways have been predicted.
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Affiliation(s)
- Kira S Makarova
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA.
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15
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Nishino T, Komori K, Ishino Y, Morikawa K. X-ray and biochemical anatomy of an archaeal XPF/Rad1/Mus81 family nuclease: similarity between its endonuclease domain and restriction enzymes. Structure 2003; 11:445-57. [PMID: 12679022 DOI: 10.1016/s0969-2126(03)00046-7] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The XPF/Rad1/Mus81-dependent nuclease family specifically cleaves branched structures generated during DNA repair, replication, and recombination, and is essential for maintaining genome stability. Here, we report the domain organization of an archaeal homolog (Hef) of this family and the X-ray crystal structure of the middle domain, with the nuclease activity. The nuclease domain architecture exhibits remarkable similarity to those of restriction endonucleases, including the correspondence of the GDX(n)ERKX(3)D signature motif in Hef to the PDX(n)(E/D)XK motif in restriction enzymes. This structural study also suggests that the XPF/Rad1/Mus81/ERCC1 proteins form a dimer through each interface of the nuclease domain and the helix-hairpin-helix domain. Simultaneous disruptions of both interfaces result in their dissociation into separate monomers, with strikingly reduced endonuclease activities.
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Affiliation(s)
- Tatsuya Nishino
- Department of Structural Biology, Biomolecular Engineering Research Institute (BERI), 6-2-3 Furuedai, Suita, 565-0874, Osaka, Japan
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16
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Serre MC, Duguet M. Enzymes That Cleave and Religate DNA at High Temperature: The Same Story with Different Actors. ACTA ACUST UNITED AC 2003; 74:37-81. [PMID: 14510073 DOI: 10.1016/s0079-6603(03)01010-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Affiliation(s)
- Marie-Claude Serre
- Laboratoire d'Enzymologie des Acides Nucléiques, Institut de Génétique et Microbiologie, Université Paris-Sud, 91405 Orsay Cedex, France
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17
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Mücke M, Grelle G, Behlke J, Kraft R, Krüger DH, Reuter M. EcoRII: a restriction enzyme evolving recombination functions? EMBO J 2002; 21:5262-8. [PMID: 12356742 PMCID: PMC129036 DOI: 10.1093/emboj/cdf514] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The restriction endonuclease EcoRII requires the cooperative interaction with two copies of the sequence 5'CCWGG for DNA cleavage. We found by limited proteolysis that EcoRII has a two-domain structure that enables this particular mode of protein-DNA interaction. The C-terminal domain is a new restriction endonuclease, EcoRII-C. In contrast to the wild-type enzyme, EcoRII-C cleaves DNA specifically at single 5'CCWGG sites. Moreover, substrates containing two or more cooperative 5'CCWGG sites are cleaved much more efficiently by EcoRII-C than by EcoRII. The N-terminal domain binds DNA specifically and attenuates the activity of EcoRII by making the enzyme dependent on a second 5'CCWGG site. Therefore, we suggest that a precursor EcoRII endonuclease acquired an additional DNA-binding domain to enable the interaction with two 5'CCWGG sites. The current EcoRII molecule could be an evolutionary intermediate between a site-specific endonuclease and a protein that functions specifically with two DNA sites such as recombinases and transposases. The combination of these functions may enable EcoRII to accomplish its own propagation similarly to transposons.
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Affiliation(s)
| | - Gerlinde Grelle
- Institut für Virologie, Medizinische Fakultät (Charité) der Humboldt-Universität zu Berlin, D-10098 Berlin and
Max-Delbrück-Centrum für Molekulare Medizin, Robert-Rössle-Strasse 10, D-13122 Berlin, Germany Corresponding author e-mail:
| | - Joachim Behlke
- Institut für Virologie, Medizinische Fakultät (Charité) der Humboldt-Universität zu Berlin, D-10098 Berlin and
Max-Delbrück-Centrum für Molekulare Medizin, Robert-Rössle-Strasse 10, D-13122 Berlin, Germany Corresponding author e-mail:
| | - Regine Kraft
- Institut für Virologie, Medizinische Fakultät (Charité) der Humboldt-Universität zu Berlin, D-10098 Berlin and
Max-Delbrück-Centrum für Molekulare Medizin, Robert-Rössle-Strasse 10, D-13122 Berlin, Germany Corresponding author e-mail:
| | | | - Monika Reuter
- Institut für Virologie, Medizinische Fakultät (Charité) der Humboldt-Universität zu Berlin, D-10098 Berlin and
Max-Delbrück-Centrum für Molekulare Medizin, Robert-Rössle-Strasse 10, D-13122 Berlin, Germany Corresponding author e-mail:
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18
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Komori K, Fujikane R, Shinagawa H, Ishino Y. Novel endonuclease in Archaea cleaving DNA with various branched structure. Genes Genet Syst 2002; 77:227-41. [PMID: 12419895 DOI: 10.1266/ggs.77.227] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
We identified a novel structure-specific endonuclease in Pyrococcus furiosus. This nuclease contains two distinct domains, which are similar to the DEAH helicase family at the N-terminal two-third and the XPF endonuclease superfamily at the C-terminal one-third of the protein, respectively. The C-terminal domain has an endonuclease activity cleaving the DNA strand at the 5'-side of nicked or flapped positions in the duplex DNA. The nuclease also incises in the proximity of the 5'-side of a branch point in the template strand for leading synthesis in the fork-structured DNA. The N-terminal helicase may work cooperatively to change the fork structure suitable for cleavage by the C-terminal endonuclease. This protein, designated as Hef (helicase-associated endonuclease for fork-structured DNA), may be a prototypical enzyme for resolving stalled forks during DNA replication, as well as working at nucleotide excision repair.
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Affiliation(s)
- Kayoko Komori
- Department of Molecular Biology, Biomolecular Engineering Research Institute, Suita, Osaka, Japan
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19
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Bitinaite J, Schildkraut I. Self-generated DNA termini relax the specificity of SgrAI restriction endonuclease. Proc Natl Acad Sci U S A 2002; 99:1164-9. [PMID: 11818524 PMCID: PMC122161 DOI: 10.1073/pnas.022346799] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The primary target of SgrAI restriction endonuclease is a multiple sequence of the form 5'-CPu/CCGGPyG. Previous work had indicated that SgrAI must bind two recognition sites simultaneously for catalysis [Bilcock, D. T., Daniels, L. E., Bath, A. J. & Halford, S. E. (1999) J. Biol. Chem. 274, 36379-36386]. In the present study, SgrAI is shown to cleave not only its canonical sequences, but also the sequences 5'-CPuCCGGPy(A,T,C) and 5'-CPuCCGGGG, both referred to as secondary sequences. On plasmid pSK7, SgrAI cleaves secondary sites 26-fold slower than the canonical site. However, the same plasmid, but without the canonical site, is cleaved 200-fold slower. We show that DNA termini generated by cleaving the canonical site for SgrAI assist in the cleavage of secondary sites. The SgrAI-termini in cis with respect to secondary site are markedly preferred over those in trans. The SgrAI-termini provided in a form of oligonucleotide duplex are also shown to stimulate canonical site cleavage. At a 40-fold molar excess of the SgrAI-termini over substrate, the SgrAI specificity is shown to improve by two orders of magnitude, because of concurrent 10-fold increase in the cleavage of canonical site and 50-fold decrease in the cleavage of secondary sites. The unconventional reaction pathway by which SgrAI utilizes the self-generated DNA termini to cleave its DNA targets has not been observed hitherto among type II restriction endonucleases. Based on our work and previous reports, a pathway of DNA binding and cleavage by the SgrAI restriction endonuclease is proposed.
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Affiliation(s)
- Jurate Bitinaite
- New England Biolabs, Inc., 32 Tozer Road, Beverly, MA 01915, USA.
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20
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Nishino T, Komori K, Ishino Y, Morikawa K. Dissection of the regional roles of the archaeal Holliday junction resolvase Hjc by structural and mutational analyses. J Biol Chem 2001; 276:35735-40. [PMID: 11441015 DOI: 10.1074/jbc.m104460200] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Hjc is an archaeal DNA endonuclease, which resolves the Holliday junction in the presence of divalent metals. Combined with mutational analyses, the x-ray structure of the Pyrococcus furiosus Hjc crystal grown in the presence of ammonium sulfate revealed a positively charged interface, rich in conserved basic residues, and the catalytic center (Nishino, T., Komori, K., Tsuchiya, D., Ishino, Y., and Morikawa, K. (2001) Structure 9, 197-T204). This structural study also suggested that the N-terminal segment and some loops of Hjc play crucial roles in the cleavage of DNA. However, a structural view of the interaction between these regions and DNA remains elusive. To clarify the regional roles of Hjc in the recognition of the Holliday junction, further structural and biochemical analyses were carried out. A new crystal form of Hjc was obtained from a polyethylene glycol solution in the absence of ammonium sulfate, and its structure has been determined at 2.16-A resolution. A comparison of the two crystal structures has revealed that the N-terminal segment undergoes a serious conformational change. The site-directed mutagenesis of the sulfate-binding site within the segment caused a dramatic decrease in the junction binding, but the mutant was still capable of cleaving DNA with a 20-fold lower efficiency. The kinetic analysis of Hjc-Holliday junction interaction indicated that mutations in the N-terminal segment greatly increased the dissociation rate constants of the Hjc-Holliday junction complex, explaining the decreased stability of the complex. This segment is also responsible for the disruption of base pairs near the junction center, through specific interactions with them. Taken together, these results imply that, in addition to the secondary effects of two basic loops, the flexible N-terminal segment plays predominant roles in the recognition of DNA conformation near the crossover and in correct positioning of the cleavage site to the catalytic center of the Hjc resolvase.
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Affiliation(s)
- T Nishino
- Department of Structural Biology and Department of Molecular Biology, Biomolecular Engineering Research Institute, 6-2-3 Furuedai, Suita, Osaka 565-0874, Japan
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21
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Kobayashi I. Behavior of restriction-modification systems as selfish mobile elements and their impact on genome evolution. Nucleic Acids Res 2001; 29:3742-56. [PMID: 11557807 PMCID: PMC55917 DOI: 10.1093/nar/29.18.3742] [Citation(s) in RCA: 390] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2001] [Revised: 07/12/2001] [Accepted: 07/23/2001] [Indexed: 11/14/2022] Open
Abstract
Restriction-modification (RM) systems are composed of genes that encode a restriction enzyme and a modification methylase. RM systems sometimes behave as discrete units of life, like viruses and transposons. RM complexes attack invading DNA that has not been properly modified and thus may serve as a tool of defense for bacterial cells. However, any threat to their maintenance, such as a challenge by a competing genetic element (an incompatible plasmid or an allelic homologous stretch of DNA, for example) can lead to cell death through restriction breakage in the genome. This post-segregational or post-disturbance cell killing may provide the RM complexes (and any DNA linked with them) with a competitive advantage. There is evidence that they have undergone extensive horizontal transfer between genomes, as inferred from their sequence homology, codon usage bias and GC content difference. They are often linked with mobile genetic elements such as plasmids, viruses, transposons and integrons. The comparison of closely related bacterial genomes also suggests that, at times, RM genes themselves behave as mobile elements and cause genome rearrangements. Indeed some bacterial genomes that survived post-disturbance attack by an RM gene complex in the laboratory have experienced genome rearrangements. The avoidance of some restriction sites by bacterial genomes may result from selection by past restriction attacks. Both bacteriophages and bacteria also appear to use homologous recombination to cope with the selfish behavior of RM systems. RM systems compete with each other in several ways. One is competition for recognition sequences in post-segregational killing. Another is super-infection exclusion, that is, the killing of the cell carrying an RM system when it is infected with another RM system of the same regulatory specificity but of a different sequence specificity. The capacity of RM systems to act as selfish, mobile genetic elements may underlie the structure and function of RM enzymes.
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Affiliation(s)
- I Kobayashi
- Department of Molecular Biology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
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22
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Birkenbihl RP, Neef K, Prangishvili D, Kemper B. Holliday junction resolving enzymes of archaeal viruses SIRV1 and SIRV2. J Mol Biol 2001; 309:1067-76. [PMID: 11399079 DOI: 10.1006/jmbi.2001.4761] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In the final stages of genetic recombination, Holliday junction resolving enzymes transform the four-way DNA intermediate into two duplex DNA molecules by introducing pairs of staggered nicks flanking the junction. This fundamental process is apparently common to cells from all three domains of life. Two cellular resolving enzymes from extremely thermophilic representatives of both kingdoms of the domain Archaea, the euryarchaeon Pyrococcus furiosus and the crenarchaeon Sulfolobus solfataricus, have been described recently. Here we report for the first time the isolation, purification and characterization of Holliday junction cleaving enzymes (Hjc) from two archaeal viruses. Both viruses, SIRV1 and SIRV2, infect Sulfolobus islandicus. Their Hjcs both consist of 121 amino acid residues (aa) differing only by 18 aa. Both proteins bind selectively to synthetic Holliday-structure analogues with an apparent dissociation constant of 25 nM. In the presence of Mg(2+) the enzymes produce identical cleavage patterns near the junction. While S. islandicus shows optimal growth at about 80 degrees C, the nucleolytic activities of recombinant SIRV2 Hjc was highest between 45 degrees C and 70 degrees C. Based on their specificity for four-way DNA structures the enzymes may play a general role in genetic recombination, DNA repair and the resolution of replicative intermediates.
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Affiliation(s)
- R P Birkenbihl
- EMBL, Structural Biology Programme, Meyerhofstr. 1, Heidelberg, 69117, Germany
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23
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24
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Abstract
Junction-resolving enzymes are ubiquitous nucleases that are important for DNA repair and recombination and act on DNA molecules containing branch points, especially four-way junctions. They show a pronounced selectivity for the structure of the DNA substrate but, despite its importance, the structural selectivity is not well understood. This poses an intriguing challenge in molecular recognition on a relatively large scale.
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Affiliation(s)
- D M Lilley
- CRC Nucleic Acid Structure Research Group, Department of Biochemistry, University of Dundee, Dundee DD1 5EH, UK.
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25
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Bond CS, Kvaratskhelia M, Richard D, White MF, Hunter WN. Structure of Hjc, a Holliday junction resolvase, from Sulfolobus solfataricus. Proc Natl Acad Sci U S A 2001; 98:5509-14. [PMID: 11331763 PMCID: PMC33243 DOI: 10.1073/pnas.091613398] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2000] [Indexed: 11/18/2022] Open
Abstract
The 2.15-A structure of Hjc, a Holliday junction-resolving enzyme from the archaeon Sulfolobus solfataricus, reveals extensive structural homology with a superfamily of nucleases that includes type II restriction enzymes. Hjc is a dimer with a large DNA-binding surface consisting of numerous basic residues surrounding the metal-binding residues of the active sites. Residues critical for catalysis, identified on the basis of sequence comparisons and site-directed mutagenesis studies, are clustered to produce two active sites in the dimer, about 29 A apart, consistent with the requirement for the introduction of paired nicks in opposing strands of the four-way DNA junction substrate. Hjc displays similarity to the restriction endonucleases in the way its specific DNA-cutting pattern is determined but uses a different arrangement of nuclease subunits. Further structural similarity to a broad group of metal/phosphate-binding proteins, including conservation of active-site location, is observed. A high degree of conservation of surface electrostatic character is observed between Hjc and T4-phage endonuclease VII despite a complete lack of structural homology. A model of the Hjc-Holliday junction complex is proposed, based on the available functional and structural data.
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Affiliation(s)
- C S Bond
- Wellcome Trust Biocentre, University of Dundee, Dundee, Tayside DD1 5EH, United Kingdom.
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26
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Déclais AC, Hadden J, Phillips SE, Lilley DM. The active site of the junction-resolving enzyme T7 endonuclease I. J Mol Biol 2001; 307:1145-58. [PMID: 11286561 DOI: 10.1006/jmbi.2001.4541] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Endonuclease I is a junction-resolving enzyme encoded by bacteriophage T7, that selectively binds and cleaves four-way DNA junctions. We have recently solved the structure of this dimeric enzyme at atomic resolution, and identified the probable catalytic residues. The putative active site comprises the side-chains of three acidic amino acids (Glu20, Asp55 and Glu65) together with a lysine residue (Lys67), and shares strong similarities with a number of type II restriction enzymes. However, it differs from a typical restriction enzyme as the proposed catalytic residues in both active sites are contributed by both polypeptides of the dimer. Mutagenesis experiments confirm the importance of all the proposed active site residues. We have carried out in vitro complementation experiments using heterodimers formed from mutants in different active site residues, showing that Glu20 is located on a different monomer from the remaining amino acid residues comprising the active site. These experiments confirm that the helix-exchanged architecture of the enzyme creates a mixed active site in solution. Such a composite active site structure should result in unilateral cleavage by the complemented heterodimer; this has been confirmed by the use of a cruciform substrate. Based upon analogy with closely similar restriction enzyme active sites and our mutagenesis experiments, we propose a two-metal ion mechanism for the hydrolytic cleavage of DNA junctions.
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Affiliation(s)
- A C Déclais
- CRC Nucleic Acid Structure Research Group, Department of Biochemistry, The University of Dundee, Dundee, DD1 4HN, UK
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27
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Nishino T, Komori K, Tsuchiya D, Ishino Y, Morikawa K. Crystal structure of the archaeal holliday junction resolvase Hjc and implications for DNA recognition. Structure 2001; 9:197-204. [PMID: 11286886 DOI: 10.1016/s0969-2126(01)00576-7] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND Homologous recombination is a crucial mechanism in determining genetic diversity and repairing damaged chromosomes. Holliday junction is the universal DNA intermediate whose interaction with proteins is one of the major events in the recombinational process. Hjc is an archaeal endonuclease, which specifically resolves the junction DNA to produce two separate recombinant DNA duplexes. The atomic structure of Hjc should clarify the mechanisms of the specific recognition with Holliday junction and the catalytic reaction. RESULTS The crystal structure of Hjc from the hyperthermophilic archaeon Pyrococcus furiosus has been determined at 2.0 A resolution. The active Hjc molecule forms a homodimer, where an extensive hydrophobic interface tightly assembles two subunits of a single compact domain. The folding of the Hjc subunit is clearly different from any other Holliday junction resolvases thus far known. Instead, it resembles those of type II restriction endonucleases, including the configurations of the active site residues, which constitute the canonical catalytic motifs. The dimeric Hjc molecule displays an extensive basic surface on one side, which contains many conserved amino acids, including those in the active site. CONCLUSIONS The architectural similarity of Hjc to restriction endonucleases allowed us to construct a putative model of the complex with Holliday junction. This model accounts for how Hjc recognizes and resolves the junction DNA in a specific manner. Mutational and biochemical analyses highlight the importance of some loops and the amino terminal region in interaction with DNA.
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Affiliation(s)
- T Nishino
- Department of Structural Biology, Biomolecular Engineering Research Institute, 6-2-3 Furuedai, Suita, Osaka 565-0874, Japan
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28
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Komori K, Sakae S, Daiyasu H, Toh H, Morikawa K, Shinagawa H, Ishino Y. Mutational analysis of the Pyrococcus furiosus holliday junction resolvase hjc revealed functionally important residues for dimer formation, junction DNA binding, and cleavage activities. J Biol Chem 2000; 275:40385-91. [PMID: 11005813 DOI: 10.1074/jbc.m006294200] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Holliday junction cleavage protein, Hjc resolvase of Pyrococcus furiosus, is the first Holliday junction resolvase to be discovered in Archaea. Although the archaeal resolvase shares certain biochemical properties with other non-archaeal junction resolvases, no amino acid sequence similarity has been identified. To investigate the structure-function relationship of this new Holliday junction resolvase, we constructed a series of mutant hjc genes using site-directed mutagenesis targeted at the residues conserved among the archaeal orthologs. The products of these mutant genes were purified to homogeneity. With analysis of the activity of the mutant proteins to bind and cleave synthetic Holliday junctions, one acidic residue, Glu-9, and two basic residues, Arg-10 and Arg-25, were found to play critical roles in enzyme action. This is in addition to the three conserved residues, Asp-33, Glu-46, and Lys-48, which are also conserved in the motif found in the type II restriction endonuclease family proteins. Two aromatic residues, Phe-68 and Phe-72, are important for the formation of the homodimer probably through hydrophobic interactions. The results of these studies have provided insights into the structure-function relationships of the archaeal Holliday junction resolvase as well as the universality and diversity of the Holliday junction cleavage reaction.
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Affiliation(s)
- K Komori
- Departments of Molecular Biology, Bioinformatics, and Structural Biology, Biomolecular Engineering Research Institute, Suita, Osaka, Japan
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