1
|
Type II Restriction-Modification System from Gardnerella vaginalis ATCC 14018. Pathogens 2020; 9:pathogens9090703. [PMID: 32867033 PMCID: PMC7559349 DOI: 10.3390/pathogens9090703] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 08/18/2020] [Accepted: 08/25/2020] [Indexed: 12/31/2022] Open
Abstract
Intensive horizontal gene transfer may generate diversity and heterogeneity within the genus Gardnerella. Restriction-modification (R-M) systems and CRISPR-Cas are the principal defense tools against foreign DNA in bacteria. Nearly half of the tested Gardnerella spp. isolates harbored the CRISPR-Cas system. Several putative R-M systems of Gardnerella spp. strains were identified in the REBASE database. However, there was no experimental evidence for restriction endonuclease (REase) activity in the isolates. We showed that G. vaginalis strain ATCC 14018 contains the REase R.Gva14018I, which recognizes GGCC and most probably generates blunt ends on cleavage. Bioinformatics evidence and the activity of recombinant methyltransferase M.Gva14018I in vivo indicate that ATCC 14018 possesses a HaeIII-like R-M system. The truncated R.Gva14018I-4 lacking the C-terminal region was expressed in Escherichia coli and displayed wild-type REase specificity. Polyclonal antibodies against R.Gva14018I-4 detected the wild-type REase in the cell lysate of ATCC 14018. The cofactor requirements for activity and bioinformatics analysis indicated that R.Gva14018I belongs to the PD-(D/E)XK family of REases. The REase-like activity was observed in 5 of 31 tested Gardnerella spp. strains, although none of these matched the DNA digestion pattern of R.Gva14018I.
Collapse
|
2
|
Horton JR, Yang J, Zhang X, Petronzio T, Fomenkov A, Wilson GG, Roberts RJ, Cheng X. Structure of HhaI endonuclease with cognate DNA at an atomic resolution of 1.0 Å. Nucleic Acids Res 2020; 48:1466-1478. [PMID: 31879785 PMCID: PMC7026639 DOI: 10.1093/nar/gkz1195] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 12/08/2019] [Accepted: 12/11/2019] [Indexed: 11/19/2022] Open
Abstract
HhaI, a Type II restriction endonuclease, recognizes the symmetric sequence 5′-GCG↓C-3′ in duplex DNA and cleaves (‘↓’) to produce fragments with 2-base, 3′-overhangs. We determined the structure of HhaI in complex with cognate DNA at an ultra-high atomic resolution of 1.0 Å. Most restriction enzymes act as dimers with two catalytic sites, and cleave the two strands of duplex DNA simultaneously, in a single binding event. HhaI, in contrast, acts as a monomer with only one catalytic site, and cleaves the DNA strands sequentially, one after the other. HhaI comprises three domains, each consisting of a mixed five-stranded β sheet with a defined function. The first domain contains the catalytic-site; the second contains residues for sequence recognition; and the third contributes to non-specific DNA binding. The active-site belongs to the ‘PD-D/EXK’ superfamily of nucleases and contains the motif SD-X11-EAK. The first two domains are similar in structure to two other monomeric restriction enzymes, HinP1I (G↓CGC) and MspI (C↓CGG), which produce fragments with 5′-overhangs. The third domain, present only in HhaI, shifts the positions of the recognition residues relative to the catalytic site enabling this enzyme to cleave the recognition sequence at a different position. The structure of M.HhaI, the biological methyltransferase partner of HhaI, was determined earlier. Together, these two structures represent the first natural pair of restriction-modification enzymes to be characterized in atomic detail.
Collapse
Affiliation(s)
- John R Horton
- Department of Epigenetics & Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Jie Yang
- Department of Epigenetics & Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Xing Zhang
- Department of Epigenetics & Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | | | | | | | | | - Xiaodong Cheng
- Department of Epigenetics & Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| |
Collapse
|
3
|
Stopar A, Coral L, Di Giacomo S, Adedeji AF, Castronovo M. Binary control of enzymatic cleavage of DNA origami by structural antideterminants. Nucleic Acids Res 2019; 46:995-1006. [PMID: 29216375 PMCID: PMC5778535 DOI: 10.1093/nar/gkx1204] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 11/30/2017] [Indexed: 12/27/2022] Open
Abstract
Controlling DNA nanostructure interaction with protein is essential in developing nanodevices with programmable function, reactivity, and stability for biological and medical applications. Here, we show that the sequence-specific action of restriction endonucleases towards sharp triangular or rectangular DNA origami exhibits a novel, binary ‘on/off’ behaviour, as canonical recognition sites are either essentially fully reactive, or strongly resistant to enzymatic cutting. Moreover, introduction of structural defects in the sharp triangle can activate an otherwise unreactive site, with a site-to-defect distance of ∼50 nm. We argue that site reactivity is dependent upon programmable, mechanical coupling in the two-dimensional DNA origami, with specific structural elements, including DNA nicks and branches proximal to the sites that can function as negative(anti) determinants of reactivity. Empirically modelling the constraints to DNA degrees of freedom associated with each recognition site in the sharp triangle can rationalize the pattern of suppressed reactivity towards nine restriction endonucleases, in substantial agreement with the experimental results. These results provide a basis for a predictive understanding of structure-reactivity correlates of specific DNA nanostructures, which will allow a better understanding of the behaviour of nucleic acids under nanoscale confinement, as well as in the rational design of functional nanodevices based on self-assembling nucleic acids.
Collapse
Affiliation(s)
- Alex Stopar
- Department of Medical and Biological Sciences, University of Udine, Udine 33100, Italy.,PhD School of Nanotechnology, Department of Physics, University of Trieste, Trieste 34127, Italy
| | - Lucia Coral
- Department of Medical and Biological Sciences, University of Udine, Udine 33100, Italy.,PhD School of Nanotechnology, Department of Physics, University of Trieste, Trieste 34127, Italy
| | - Stefano Di Giacomo
- Department of Medical and Biological Sciences, University of Udine, Udine 33100, Italy.,Department of Chemistry, Biology and Biotechnology, University of Perugia, Perugia 06123, Italy
| | - Abimbola F Adedeji
- Regional Referral Centre for Rare Diseases, Azienda Sanitaria Universitaria Integrata di Udine, 33100 Udine, Italy.,School of Food Science and Nutrition, University of Leeds, Leeds LS2 9JT, UK
| | - Matteo Castronovo
- Department of Medical and Biological Sciences, University of Udine, Udine 33100, Italy.,PhD School of Nanotechnology, Department of Physics, University of Trieste, Trieste 34127, Italy.,Regional Referral Centre for Rare Diseases, Azienda Sanitaria Universitaria Integrata di Udine, 33100 Udine, Italy.,School of Food Science and Nutrition, University of Leeds, Leeds LS2 9JT, UK
| |
Collapse
|
4
|
Sasheva P, Grossniklaus U. Differentially Methylated Region-Representational Difference Analysis (DMR-RDA): A Powerful Method to Identify DMRs in Uncharacterized Genomes. Methods Mol Biol 2018; 1456:113-125. [PMID: 27770362 DOI: 10.1007/978-1-4899-7708-3_10] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Abstract
Over the last years, it has become increasingly clear that environmental influences can affect the epigenomic landscape and that some epigenetic variants can have heritable, phenotypic effects. While there are a variety of methods to perform genome-wide analyses of DNA methylation in model organisms, this is still a challenging task for non-model organisms without a reference genome. Differentially methylated region-representational difference analysis (DMR-RDA) is a sensitive and powerful PCR-based technique that isolates DNA fragments that are differentially methylated between two otherwise identical genomes. The technique does not require special equipment and is independent of prior knowledge about the genome. It is even applicable to genomes that have high complexity and a large size, being the method of choice for the analysis of plant non-model systems.
Collapse
Affiliation(s)
- Pavlina Sasheva
- Department of Plant and Microbial Biology & Zurich-Basel Plant Science Center, University of Zurich, Zollikerstrasse 107, 8008, Zürich, Switzerland
| | - Ueli Grossniklaus
- Department of Plant and Microbial Biology & Zurich-Basel Plant Science Center, University of Zurich, Zollikerstrasse 107, 8008, Zürich, Switzerland.
- Bayer CropScience AG, Alfred-Nobel-Straße 50, 40789, Monheim am Rhein, Germany.
| |
Collapse
|
5
|
Claeys Bouuaert C, Chalmers R. A single active site in the mariner transposase cleaves DNA strands of opposite polarity. Nucleic Acids Res 2017; 45:11467-11478. [PMID: 29036477 PMCID: PMC5714172 DOI: 10.1093/nar/gkx826] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2017] [Accepted: 09/08/2017] [Indexed: 01/01/2023] Open
Abstract
The RNase H structural fold defines a large family of nucleic acid metabolizing enzymes that catalyze phosphoryl transfer reactions using two divalent metal ions in the active site. Almost all of these reactions involve only one strand of the nucleic acid substrates. In contrast, cut-and-paste transposases cleave two DNA strands of opposite polarity, which is usually achieved via an elegant hairpin mechanism. In the mariner transposons, the hairpin intermediate is absent and key aspects of the mechanism by which the transposon ends are cleaved remained unknown. Here, we characterize complexes involved prior to catalysis, which define an asymmetric pathway for transpososome assembly. Using mixtures of wild-type and catalytically inactive transposases, we show that all the catalytic steps of transposition occur within the context of a dimeric transpososome. Crucially, we find that each active site of a transposase dimer is responsible for two hydrolysis and one transesterification reaction at the same transposon end. These results provide the first strong evidence that a DDE/D active site can hydrolyze DNA strands of opposite polarity, a mechanism that has rarely been observed with any type of nuclease.
Collapse
Affiliation(s)
- Corentin Claeys Bouuaert
- School of Biomedical Sciences, University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UK
| | - Ronald Chalmers
- School of Biomedical Sciences, University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UK
| |
Collapse
|
6
|
Tamulaitiene G, Jovaisaite V, Tamulaitis G, Songailiene I, Manakova E, Zaremba M, Grazulis S, Xu SY, Siksnys V. Restriction endonuclease AgeI is a monomer which dimerizes to cleave DNA. Nucleic Acids Res 2017; 45:3547-3558. [PMID: 28039325 PMCID: PMC5389614 DOI: 10.1093/nar/gkw1310] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 12/13/2016] [Accepted: 12/19/2016] [Indexed: 01/19/2023] Open
Abstract
Although all Type II restriction endonucleases catalyze phosphodiester bond hydrolysis within or close to their DNA target sites, they form different oligomeric assemblies ranging from monomers, dimers, tetramers to higher order oligomers to generate a double strand break in DNA. Type IIP restriction endonuclease AgeI recognizes a palindromic sequence 5΄-A/CCGGT-3΄ and cuts it ('/' denotes the cleavage site) producing staggered DNA ends. Here, we present crystal structures of AgeI in apo and DNA-bound forms. The structure of AgeI is similar to the restriction enzymes that share in their target sites a conserved CCGG tetranucleotide and a cleavage pattern. Structure analysis and biochemical data indicate, that AgeI is a monomer in the apo-form both in the crystal and in solution, however, it binds and cleaves the palindromic target site as a dimer. DNA cleavage mechanism of AgeI is novel among Type IIP restriction endonucleases.
Collapse
Affiliation(s)
- Giedre Tamulaitiene
- Institute of Biotechnology, Vilnius University, Sauletekio al. 7, LT-10257 Vilnius, Lithuania
| | - Virginija Jovaisaite
- Institute of Biotechnology, Vilnius University, Sauletekio al. 7, LT-10257 Vilnius, Lithuania
| | - Gintautas Tamulaitis
- Institute of Biotechnology, Vilnius University, Sauletekio al. 7, LT-10257 Vilnius, Lithuania
| | - Inga Songailiene
- Institute of Biotechnology, Vilnius University, Sauletekio al. 7, LT-10257 Vilnius, Lithuania
| | - Elena Manakova
- Institute of Biotechnology, Vilnius University, Sauletekio al. 7, LT-10257 Vilnius, Lithuania
| | - Mindaugas Zaremba
- Institute of Biotechnology, Vilnius University, Sauletekio al. 7, LT-10257 Vilnius, Lithuania
| | - Saulius Grazulis
- Institute of Biotechnology, Vilnius University, Sauletekio al. 7, LT-10257 Vilnius, Lithuania
| | - Shuang-yong Xu
- New England Biolabs, Inc. 240 County Road, Ipswich, MA 01938, USA
| | - Virginijus Siksnys
- Institute of Biotechnology, Vilnius University, Sauletekio al. 7, LT-10257 Vilnius, Lithuania
| |
Collapse
|
7
|
Hoppins JJ, Gruber DR, Miears HL, Kiryutin AS, Kasymov RD, Petrova DV, Endutkin AV, Popov AV, Yurkovskaya AV, Fedechkin SO, Brockerman JA, Zharkov DO, Smirnov SL. 8-Oxoguanine Affects DNA Backbone Conformation in the EcoRI Recognition Site and Inhibits Its Cleavage by the Enzyme. PLoS One 2016; 11:e0164424. [PMID: 27749894 PMCID: PMC5066940 DOI: 10.1371/journal.pone.0164424] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 09/23/2016] [Indexed: 12/13/2022] Open
Abstract
8-oxoguanine is one of the most abundant and impactful oxidative DNA lesions. However, the reasons underlying its effects, especially those not directly explained by the altered base pairing ability, are poorly understood. We report the effect of the lesion on the action of EcoRI, a widely used restriction endonuclease. Introduction of 8-oxoguanine inside, or adjacent to, the GAATTC recognition site embedded within the Drew—Dickerson dodecamer sequence notably reduced the EcoRI activity. Solution NMR revealed that 8-oxoguanine in the DNA duplex causes substantial alterations in the sugar—phosphate backbone conformation, inducing a BI→BII transition. Moreover, molecular dynamics of the complex suggested that 8-oxoguanine, although does not disrupt the sequence-specific contacts formed by the enzyme with DNA, shifts the distribution of BI/BII backbone conformers. Based on our data, we propose that the disruption of enzymatic cleavage can be linked with the altered backbone conformation and dynamics in the free oxidized DNA substrate and, possibly, at the protein—DNA interface.
Collapse
Affiliation(s)
- Joanna J. Hoppins
- Chemistry Department, Western Washington University, Bellingham, WA, United States of America
| | - David R. Gruber
- Chemistry Department, Western Washington University, Bellingham, WA, United States of America
| | - Heather L. Miears
- Chemistry Department, Western Washington University, Bellingham, WA, United States of America
| | - Alexey S. Kiryutin
- SB RAS International Tomography Center, Novosibirsk, Russia
- Novosibirsk State University, Novosibirsk, Russia
| | - Rustem D. Kasymov
- SB RAS Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia
- Institute of Biochemistry, Stuttgart University, Stuttgart, Germany
| | - Darya V. Petrova
- Novosibirsk State University, Novosibirsk, Russia
- SB RAS Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia
| | - Anton V. Endutkin
- Novosibirsk State University, Novosibirsk, Russia
- SB RAS Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia
| | - Alexander V. Popov
- SB RAS Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia
| | - Alexandra V. Yurkovskaya
- SB RAS International Tomography Center, Novosibirsk, Russia
- Novosibirsk State University, Novosibirsk, Russia
| | - Stanislav O. Fedechkin
- Chemistry Department, Western Washington University, Bellingham, WA, United States of America
- University of California Santa Cruz, Program in Biomedical Science and Engineering, Santa Cruz, CA, United States of America
| | - Jacob A. Brockerman
- Chemistry Department, Western Washington University, Bellingham, WA, United States of America
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada
| | - Dmitry O. Zharkov
- Novosibirsk State University, Novosibirsk, Russia
- SB RAS Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia
- * E-mail: (SLS); (DOZ)
| | - Serge L. Smirnov
- Chemistry Department, Western Washington University, Bellingham, WA, United States of America
- * E-mail: (SLS); (DOZ)
| |
Collapse
|
8
|
Horton JR, Borgaro JG, Griggs RM, Quimby A, Guan S, Zhang X, Wilson GG, Zheng Y, Zhu Z, Cheng X. Structure of 5-hydroxymethylcytosine-specific restriction enzyme, AbaSI, in complex with DNA. Nucleic Acids Res 2014; 42:7947-59. [PMID: 24895434 PMCID: PMC4081097 DOI: 10.1093/nar/gku497] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AbaSI, a member of the PvuRts1I-family of modification-dependent restriction endonucleases, cleaves deoxyribonucleic acid (DNA) containing 5-hydroxymethylctosine (5hmC) and glucosylated 5hmC (g5hmC), but not DNA containing unmodified cytosine. AbaSI has been used as a tool for mapping the genomic locations of 5hmC, an important epigenetic modification in the DNA of higher organisms. Here we report the crystal structures of AbaSI in the presence and absence of DNA. These structures provide considerable, although incomplete, insight into how this enzyme acts. AbaSI appears to be mainly a homodimer in solution, but interacts with DNA in our structures as a homotetramer. Each AbaSI subunit comprises an N-terminal, Vsr-like, cleavage domain containing a single catalytic site, and a C-terminal, SRA-like, 5hmC-binding domain. Two N-terminal helices mediate most of the homodimer interface. Dimerization brings together the two catalytic sites required for double-strand cleavage, and separates the 5hmC binding-domains by ∼70 Å, consistent with the known activity of AbaSI which cleaves DNA optimally between symmetrically modified cytosines ∼22 bp apart. The eukaryotic SET and RING-associated (SRA) domains bind to DNA containing 5-methylcytosine (5mC) in the hemi-methylated CpG sequence. They make contacts in both the major and minor DNA grooves, and flip the modified cytosine out of the helix into a conserved binding pocket. In contrast, the SRA-like domain of AbaSI, which has no sequence specificity, contacts only the minor DNA groove, and in our current structures the 5hmC remains intra-helical. A conserved, binding pocket is nevertheless present in this domain, suitable for accommodating 5hmC and g5hmC. We consider it likely, therefore, that base-flipping is part of the recognition and cleavage mechanism of AbaSI, but that our structures represent an earlier, pre-flipped stage, prior to actual recognition.
Collapse
Affiliation(s)
- John R Horton
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road, Atlanta, Georgia 30322, USA
| | - Janine G Borgaro
- New England Biolabs, Inc., 240 County Road, Ipswich, MA 01938, USA
| | - Rose M Griggs
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road, Atlanta, Georgia 30322, USA
| | - Aine Quimby
- New England Biolabs, Inc., 240 County Road, Ipswich, MA 01938, USA
| | - Shengxi Guan
- New England Biolabs, Inc., 240 County Road, Ipswich, MA 01938, USA
| | - Xing Zhang
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road, Atlanta, Georgia 30322, USA
| | | | - Yu Zheng
- New England Biolabs, Inc., 240 County Road, Ipswich, MA 01938, USA
| | - Zhenyu Zhu
- New England Biolabs, Inc., 240 County Road, Ipswich, MA 01938, USA
| | - Xiaodong Cheng
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road, Atlanta, Georgia 30322, USA
| |
Collapse
|
9
|
Park JM, Yang CY, Park H, Kim JM. Development of a genus-specific PCR combined with ARDRA for the identification of Leuconostoc species in kimchi. Food Sci Biotechnol 2014. [DOI: 10.1007/s10068-014-0070-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
|
10
|
Abstract
Nucleases cleave the phosphodiester bonds of nucleic acids and may be endo or exo, DNase or RNase, topoisomerases, recombinases, ribozymes, or RNA splicing enzymes. In this review, I survey nuclease activities with known structures and catalytic machinery and classify them by reaction mechanism and metal-ion dependence and by their biological function ranging from DNA replication, recombination, repair, RNA maturation, processing, interference, to defense, nutrient regeneration or cell death. Several general principles emerge from this analysis. There is little correlation between catalytic mechanism and biological function. A single catalytic mechanism can be adapted in a variety of reactions and biological pathways. Conversely, a single biological process can often be accomplished by multiple tertiary and quaternary folds and by more than one catalytic mechanism. Two-metal-ion-dependent nucleases comprise the largest number of different tertiary folds and mediate the most diverse set of biological functions. Metal-ion-dependent cleavage is exclusively associated with exonucleases producing mononucleotides and endonucleases that cleave double- or single-stranded substrates in helical and base-stacked conformations. All metal-ion-independent RNases generate 2',3'-cyclic phosphate products, and all metal-ion-independent DNases form phospho-protein intermediates. I also find several previously unnoted relationships between different nucleases and shared catalytic configurations.
Collapse
|
11
|
Vanamee ES, Viadiu H, Chan SH, Ummat A, Hartline AM, Xu SY, Aggarwal AK. Asymmetric DNA recognition by the OkrAI endonuclease, an isoschizomer of BamHI. Nucleic Acids Res 2010; 39:712-9. [PMID: 20833632 PMCID: PMC3025578 DOI: 10.1093/nar/gkq779] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Restriction enzymes share little or no sequence homology with the exception of isoschizomers, or enzymes that recognize and cleave the same DNA sequence. We present here the structure of a BamHI isoschizomer, OkrAI, bound to the same DNA sequence (TATGGATCCATA) as that cocrystallized with BamHI. We show that OkrAI is a more minimal version of BamHI, lacking not only the N- and C-terminal helices but also an internal 310 helix and containing β-strands that are shorter than those in BamHI. Despite these structural differences, OkrAI recognizes the DNA in a remarkably similar manner to BamHI, including asymmetric contacts via C-terminal ‘arms’ that appear to ‘compete’ for the minor groove. However, the arms are shorter than in BamHI. We observe similar DNA-binding affinities between OkrAI and BamHI but OkrAI has higher star activity (at 37°C) compared to BamHI. Together, the OkrAI and BamHI structures offer a rare opportunity to compare two restriction enzymes that work on exactly the same DNA substrate.
Collapse
Affiliation(s)
- Eva Scheuring Vanamee
- Department of Structural and Chemical Biology, Mount Sinai School of Medicine, New York, NY 10029, USA
| | | | | | | | | | | | | |
Collapse
|
12
|
Raskó T, Dér A, Klement E, Slaska-Kiss K, Pósfai E, Medzihradszky KF, Marshak DR, Roberts RJ, Kiss A. BspRI restriction endonuclease: cloning, expression in Escherichia coli and sequential cleavage mechanism. Nucleic Acids Res 2010; 38:7155-66. [PMID: 20587501 PMCID: PMC2978348 DOI: 10.1093/nar/gkq567] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The GGCC-specific restriction endonuclease BspRI is one of the few Type IIP restriction endonucleases, which were suggested to be a monomer. Amino acid sequence information obtained by Edman sequencing and mass spectrometry analysis was used to clone the gene encoding BspRI. The bspRIR gene is located adjacently to the gene of the cognate modification methyltransferase and encodes a 304 aa protein. Expression of the bspRIR gene in Escherichia coli was dependent on the replacement of the native TTG initiation codon with an ATG codon, explaining previous failures in cloning the gene using functional selection. A plasmid containing a single BspRI recognition site was used to analyze kinetically nicking and second-strand cleavage under steady-state conditions. Cleavage of the supercoiled plasmid went through a relaxed intermediate indicating sequential hydrolysis of the two strands. Results of the kinetic analysis of the first- and second-strand cleavage are consistent with cutting the double-stranded substrate site in two independent binding events. A database search identified eight putative restriction-modification systems in which the predicted endonucleases as well as the methyltransferases share high sequence similarity with the corresponding protein of the BspRI system. BspRI and the related putative restriction endonucleases belong to the PD-(D/E)XK nuclease superfamily.
Collapse
Affiliation(s)
- Tamás Raskó
- Institute of Biochemistry, Proteomics Research Group, Biological Research Center of the Hungarian Academy of Sciences, Temesvári krt. 62, 6726 Szeged, Hungary
| | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Gao M, Skolnick J. DBD-Hunter: a knowledge-based method for the prediction of DNA-protein interactions. Nucleic Acids Res 2008; 36:3978-92. [PMID: 18515839 PMCID: PMC2475642 DOI: 10.1093/nar/gkn332] [Citation(s) in RCA: 118] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The structures of DNA–protein complexes have illuminated the diversity of DNA–protein binding mechanisms shown by different protein families. This lack of generality could pose a great challenge for predicting DNA–protein interactions. To address this issue, we have developed a knowledge-based method, DNA-binding Domain Hunter (DBD-Hunter), for identifying DNA-binding proteins and associated binding sites. The method combines structural comparison and the evaluation of a statistical potential, which we derive to describe interactions between DNA base pairs and protein residues. We demonstrate that DBD-Hunter is an accurate method for predicting DNA-binding function of proteins, and that DNA-binding protein residues can be reliably inferred from the corresponding templates if identified. In benchmark tests on ∼4000 proteins, our method achieved an accuracy of 98% and a precision of 84%, which significantly outperforms three previous methods. We further validate the method on DNA-binding protein structures determined in DNA-free (apo) state. We show that the accuracy of our method is only slightly affected on apo-structures compared to the performance on holo-structures cocrystallized with DNA. Finally, we apply the method to ∼1700 structural genomics targets and predict that 37 targets with previously unknown function are likely to be DNA-binding proteins. DBD-Hunter is freely available at http://cssb.biology.gatech.edu/skolnick/webservice/DBD-Hunter/.
Collapse
Affiliation(s)
- Mu Gao
- Center for the Study of Systems Biology, School of Biology, Georgia Institute of Technology, 250 14th Street NW, Atlanta, GA 30318, USA
| | | |
Collapse
|
14
|
Functional circularity of legitimate Qbeta replicase templates. J Mol Biol 2008; 379:414-27. [PMID: 18466922 PMCID: PMC7173182 DOI: 10.1016/j.jmb.2008.03.074] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2007] [Revised: 03/12/2008] [Accepted: 03/31/2008] [Indexed: 11/21/2022]
Abstract
Qbeta replicase (RNA-directed RNA polymerase of bacteriophage Qbeta) exponentially amplifies certain RNAs in vitro. Previous studies have shown that Qbeta replicase can initiate and elongate on a variety of RNAs; however, only a minute fraction of them are recognized as 'legitimate' templates. Guanosine 5'-triphosphate (GTP)-dependent initiation on a legitimate template generates a stable replicative complex capable of elongation in the presence of aurintricarboxylic acid, a powerful inhibitor of RNA-protein interactions. On the contrary, initiation on an illegitimate template is GTP independent and does not result in the aurintricarboxylic-acid-resistant replicative complex. This article demonstrates that the 3' and 5' termini of a legitimate template cooperate during and after the initiation step. Breach of the cooperation by dividing the template into fragments or by introducing point mutations at the 5' terminus reduces the rate and the yield of initiation, increases the GTP requirement, decreases the overall rate of template copying, and destabilizes the postinitiation replicative complex. These results revive the old idea of a functional circularity of legitimate Qbeta replicase templates and complement the increasing body of evidence that functional circularity may be a common property of RNA templates directing the synthesis of either RNA or protein molecules.
Collapse
|
15
|
Kosinski J, Kubareva E, Bujnicki JM. A model of restriction endonuclease MvaI in complex with DNA: a template for interpretation of experimental data and a guide for specificity engineering. Proteins 2007; 68:324-36. [PMID: 17407166 DOI: 10.1002/prot.21460] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
R.MvaI is a Type II restriction enzyme (REase), which specifically recognizes the pentanucleotide DNA sequence 5'-CCWGG-3' (W indicates A or T). It belongs to a family of enzymes, which recognize related sequences, including 5'-CCSGG-3' (S indicates G or C) in the case of R.BcnI, or 5'-CCNGG-3' (where N indicates any nucleoside) in the case of R.ScrFI. REases from this family hydrolyze the phosphodiester bond in the DNA between the 2nd and 3rd base in both strands, thereby generating a double strand break with 5'-protruding single nucleotides. So far, no crystal structures of REases with similar cleavage patterns have been solved. Characterization of sequence-structure-function relationships in this family would facilitate understanding of evolution of sequence specificity among REases and could aid in engineering of enzymes with new specificities. However, sequences of R.MvaI or its homologs show no significant similarity to any proteins with known structures, thus precluding straightforward comparative modeling. We used a fold recognition approach to identify a remote relationship between R.MvaI and the structure of DNA repair enzyme MutH, which belongs to the PD-(D/E)XK superfamily together with many other REases. We constructed a homology model of R.MvaI and used it to predict functionally important amino acid residues and the mode of interaction with the DNA. In particular, we predict that only one active site of R.MvaI interacts with the DNA target at a time, and the cleavage of both strands (5'-CCAGG-3' and 5'-CCTGG-3') is achieved by two independent catalytic events. The model is in good agreement with the available experimental data and will serve as a template for further analyses of R.MvaI, R.BcnI, R.ScrFI and other related enzymes.
Collapse
Affiliation(s)
- Jan Kosinski
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology, Trojdena 4, 02-109 Warsaw, Poland.
| | | | | |
Collapse
|
16
|
Xu SY, Zhu Z, Zhang P, Chan SH, Samuelson JC, Xiao J, Ingalls D, Wilson GG. Discovery of natural nicking endonucleases Nb.BsrDI and Nb.BtsI and engineering of top-strand nicking variants from BsrDI and BtsI. Nucleic Acids Res 2007; 35:4608-18. [PMID: 17586812 PMCID: PMC1950550 DOI: 10.1093/nar/gkm481] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2007] [Revised: 05/30/2007] [Accepted: 06/01/2007] [Indexed: 11/13/2022] Open
Abstract
BsrDI and BtsI restriction endonucleases recognize and cleave double-strand DNA at the sequences GCAATG (2/0) and GCAGTG (2/0), respectively. We have purified and partially characterized these two enzymes, and analyzed the genes that encode them. BsrDI and BtsI are unusual in two respects: each cleaves DNA as a heterodimer of one large subunit (B subunit) and one small subunit (A subunit); and, in the absence of their small subunits, the large subunits behave as sequence-specific DNA nicking enzymes and only nick the bottom strand of the sequences at these respective positions: GCAATG (-/0) and GCAGTG (-/0). We refer to the single subunit, the bottom-strand nicking forms as 'hemidimers'. Amino acid sequence comparisons reveal that BsrDI and BtsI belong to a family of restriction enzymes that possess two catalytic sites: a canonical PD-X(n)-EXK and a second non-canonical PD-X(n)-E-X12-QR. Interestingly, the other family members, which include BsrI (ACTGG 1/-1) and BsmI/Mva1269I (GAATGC 1/-1) are single polypeptide chains, i.e. monomers, rather than heterodimers. In BsrDI and BtsI, the two catalytic sites are found in two separate subunits. Site-directed mutagenesis confirmed that the canonical catalytic site located at the N-terminus of the large subunit is responsible for the bottom-strand cleavage, whereas the non-canonical catalytic site located in the small subunit is responsible for hydrolysis of the top strand. Top-strand specific nicking variants, Nt.BsrDI and Nt.BtsI, were successfully engineered by combining the catalytic-deficient B subunit with wild-type A subunit.
Collapse
Affiliation(s)
- Shuang-Yong Xu
- New England Biolabs, Inc., 240 County Road, Ipswich, MA 01938, USA.
| | | | | | | | | | | | | | | |
Collapse
|