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Nomura K, Onda K, Murase H, Hashiya F, Ono Y, Terai G, Oka N, Asai K, Suzuki D, Takahashi N, Hiraoka H, Inagaki M, Kimura Y, Shimizu Y, Abe N, Abe H. Development of PCR primers enabling the design of flexible sticky ends for efficient concatenation of long DNA fragments. RSC Chem Biol 2024; 5:360-371. [PMID: 38576723 PMCID: PMC10989509 DOI: 10.1039/d3cb00212h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 02/19/2024] [Indexed: 04/06/2024] Open
Abstract
We developed chemically modified PCR primers that allow the design of flexible sticky ends by introducing a photo-cleavable group at the phosphate moiety. Nucleic acid derivatives containing o-nitrobenzyl photo-cleavable groups with a tert-butyl group at the benzyl position were stable during strong base treatment for oligonucleotide synthesis and thermal cycling in PCR reactions. PCR using primers incorporating these nucleic acid derivatives confirmed that chain extension reactions completely stopped at position 1 before and after the site of the photo-cleavable group was introduced. DNA fragments of 2 and 3 kbp, with sticky ends of 50 bases, were successfully concatenated with a high yield of 77%. A plasmid was constructed using this method. Finally, we applied this approach to construct a 48.5 kbp lambda phage DNA, which is difficult to achieve using restriction enzyme-based methods. After 7 days, we were able to confirm the generation of DNA of the desired length. Although the efficiency is yet to be improved, the chemically modified PCR primer offers potential to complement enzymatic methods and serve as a DNA concatenation technique.
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Affiliation(s)
- Kohei Nomura
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku Nagoya Aichi 464-8602 Japan
| | - Kaoru Onda
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku Nagoya Aichi 464-8602 Japan
| | - Hirotaka Murase
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku Nagoya Aichi 464-8602 Japan
| | - Fumitaka Hashiya
- Research Center for Materials Science, Nagoya University Furo-cho, Chikusa-ku Nagoya Aichi 464-8602 Japan
- CREST, Japan Science and Technology Agency 7 Gobancho Chiyoda-ku Tokyo 102-0076 Japan
| | - Yukiteru Ono
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, University of Tokyo Kashiwanoha, Kashiwa Chiba 277-8561 Japan
| | - Goro Terai
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, University of Tokyo Kashiwanoha, Kashiwa Chiba 277-8561 Japan
| | - Natsuhisa Oka
- Department of Chemistry and Biomolecular Science Faculty of Engineering, Gifu University Gifu 501-1193 Japan
| | - Kiyoshi Asai
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, University of Tokyo Kashiwanoha, Kashiwa Chiba 277-8561 Japan
| | - Daisuke Suzuki
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku Nagoya Aichi 464-8602 Japan
| | - Naho Takahashi
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku Nagoya Aichi 464-8602 Japan
| | - Haruka Hiraoka
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku Nagoya Aichi 464-8602 Japan
| | - Masahito Inagaki
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku Nagoya Aichi 464-8602 Japan
| | - Yasuaki Kimura
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku Nagoya Aichi 464-8602 Japan
| | - Yoshihiro Shimizu
- Laboratory for Cell-Free Protein Synthesis, RIKEN Center for Biosystems Dynamics Research Suita Osaka 565-0874 Japan
| | - Naoko Abe
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku Nagoya Aichi 464-8602 Japan
| | - Hiroshi Abe
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku Nagoya Aichi 464-8602 Japan
- Research Center for Materials Science, Nagoya University Furo-cho, Chikusa-ku Nagoya Aichi 464-8602 Japan
- CREST, Japan Science and Technology Agency 7 Gobancho Chiyoda-ku Tokyo 102-0076 Japan
- Institute for Glyco-core Research (iGCORE), Nagoya University Furo-cho, Chikusa-ku Nagoya Aichi 464-8601 Japan
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2
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Im J, Kim S, Park S, Wang SX, Lee JR. Evaluation of restriction and Cas endonuclease kinetics using matrix-insensitive magnetic biosensors. Biosens Bioelectron 2024; 249:116017. [PMID: 38262299 PMCID: PMC10867820 DOI: 10.1016/j.bios.2024.116017] [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: 11/13/2023] [Revised: 01/02/2024] [Accepted: 01/07/2024] [Indexed: 01/25/2024]
Abstract
The enzymatic actions of endonucleases in vivo can be altered due to bound substrates and differences in local environments, including enzyme concentration, pH, salinity, ionic strength, and temperature. Thus, accurate estimation of enzymatic reactions in vivo using matrix-dependent methods in solution can be challenging. Here, we report a matrix-insensitive magnetic biosensing platform that enables the measurement of endonuclease activity under different conditions with varying pH, salinity, ionic strength, and temperature. Using biosensor arrays and orthogonal pairs of oligonucleotides, we quantitatively characterized the enzymatic activity of EcoRI under different buffer conditions and in the presence of inhibitors. To mimic a more physiological environment, we monitored the sequence-dependent star activity of EcoRI under unconventional conditions. Furthermore, enzymatic activity was measured in cell culture media, saliva, and serum. Last, we estimated the effective cleavage rates of Cas12a on anchored single-strand DNAs using this platform, which more closely resembles in vivo settings. This platform will facilitate precise characterization of restriction and Cas endonucleases under various conditions.
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Affiliation(s)
- Jisoo Im
- Division of Mechanical and Biomedical Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea; Graduate Program in Smart Factory, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Songeun Kim
- Division of Mechanical and Biomedical Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea; Graduate Program in Smart Factory, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Suhyeon Park
- Division of Mechanical and Biomedical Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea; Graduate Program in Smart Factory, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Shan X Wang
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, 94305, USA; Department of Electrical Engineering, Stanford University, Stanford, CA 94305, USA
| | - Jung-Rok Lee
- Division of Mechanical and Biomedical Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea; Graduate Program in Smart Factory, Ewha Womans University, Seoul, 03760, Republic of Korea.
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3
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Mandal SC, Chakrabarti J. In-silicon studies on hydration in EcoRI-cognate DNA complex. Biophys Chem 2023; 303:107121. [PMID: 37837721 DOI: 10.1016/j.bpc.2023.107121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 09/27/2023] [Accepted: 10/01/2023] [Indexed: 10/16/2023]
Abstract
Restriction endonucleases (REs) cleave DNA at specific site in presence of Mg2+ ion. Experiments further emphasize the role of hydration in metal ion specificity and sequence specificity of DNA cleavage. However, the relation between hydration and specificity has not been understood till date. This leads us to study via all-atom molecular dynamics (MD) simulations how the hydration around the scissile phosphate group changes in presence of Mg2+ and Ca2+ and depend on the DNA sequence. We observe the least number of hydrogen bonds around the scissile phosphate group in presence of Mg2+ ion. We further find that the hydrogen bonds decrease at the scissile phosphate on mutating one base pair in the cleavage region of the DNA in Mg2+ loaded EcoRI-DNA complex. We also perform steered MD simulations and observe that the rate of decrease of fraction of hydrogen bonds is slower in the mutated complex than the unmutated complex.
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Affiliation(s)
- Sasthi Charan Mandal
- Department of Physics of Complex Systems, S.N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700106, India
| | - Jaydeb Chakrabarti
- Department of Physics of Complex Systems, S.N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700106, India..
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4
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Santoshi M, Engleng B, Eligar SM, Ratnakar IS, Nagamalleshwari E, Nagaraja V. Identification and characterization of a new HNH restriction endonuclease with unusual properties. Appl Microbiol Biotechnol 2023; 107:6263-6275. [PMID: 37626186 DOI: 10.1007/s00253-023-12717-8] [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: 06/27/2023] [Revised: 07/20/2023] [Accepted: 07/28/2023] [Indexed: 08/27/2023]
Abstract
Restriction-modification (R-M) systems form a large superfamily constituting bacterial innate immunity mechanism. The restriction endonucleases (REases) are very diverse in subunit structure, DNA recognition, co-factor requirement, and mechanism of action. Among the different catalytic motifs, HNH active sites containing REases are the second largest group distinguished by the presence of the ββα-metal finger fold. KpnI is the first member of the HNH-family REases whose homologs are present in many bacteria of Enterobacteriaceae having varied degrees of sequence similarity between them. Considering that the homologs with a high similarity may have retained KpnI-like properties, while those with a low similarity could be different, we have characterized a distant KpnI homolog present in a pathogenic Klebsiella pneumoniae NTUH K2044. A comparison of the properties of KpnI and KpnK revealed that despite their similarity and the HNH motif, these two enzymes have different properties viz oligomerization, cleavage pattern, metal ion requirement, recognition sequence, and sequence specificity. Unlike KpnI, KpnK is a monomer in solution, nicks double-stranded DNA, recognizes degenerate sequence, and catalyses the degradation of DNA into smaller products after the initial cleavage at preferred sites. Due to several distinctive properties, it can be classified as a variant of the Type IIS enzyme having nicking endonuclease activity. KEY POINTS: • KpnK is a distant homolog of KpnI and belongs to the ββα-metal finger superfamily. • Both KpnI and KpnK have widespread occurrence in K. pneumoniae strains. • KpnK is a Type IIS restriction endonuclease with a single-strand nicking property.
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Affiliation(s)
- Meghna Santoshi
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bengaluru, India
| | - Bharat Engleng
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bengaluru, India
| | - Sachin M Eligar
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bengaluru, India
| | - Immadi Siva Ratnakar
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bengaluru, India
| | - Easa Nagamalleshwari
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bengaluru, India
| | - Valakunja Nagaraja
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bengaluru, India.
- Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India.
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5
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Hartenian E, Mendez AS, Didychuk AL, Khosla S, Glaunsinger B. DNA processing by the Kaposi's sarcoma-associated herpesvirus alkaline exonuclease SOX contributes to viral gene expression and infectious virion production. Nucleic Acids Res 2022; 51:182-197. [PMID: 36537232 PMCID: PMC9841436 DOI: 10.1093/nar/gkac1190] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 11/22/2022] [Accepted: 11/29/2022] [Indexed: 12/24/2022] Open
Abstract
Alkaline exonucleases (AE) are present in several large DNA viruses including bacteriophage λ and herpesviruses, where they play roles in viral DNA processing during genome replication. Given the genetic conservation of AEs across viruses infecting different kingdoms of life, these enzymes likely assume central roles in the lifecycles of viruses where they have yet to be well characterized. Here, we applied a structure-guided functional analysis of the bifunctional AE in the oncogenic human gammaherpesvirus Kaposi's sarcoma-associated herpesvirus (KSHV), called SOX. In addition to identifying a preferred DNA substrate preference for SOX, we define key residues important for DNA binding and DNA processing, and how SOX activity on DNA partially overlaps with its functionally separable cleavage of mRNA. By engineering these SOX mutants into KSHV, we reveal roles for its DNase activity in viral gene expression and infectious virion production. Our results provide mechanistic insight into gammaherpesviral AE activity as well as areas of functional conservation between this mammalian virus AE and its distant relative in phage λ.
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Affiliation(s)
| | - Aaron S Mendez
- Correspondence may also be addressed to Aaron S. Mendez.
| | - Allison L Didychuk
- Department of Plant and Microbial Biology, University of California Berkeley, CA 94720, USA,Department of Molecular Biophysics & Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Shivani Khosla
- Department of Molecular and Cell Biology, University of California Berkeley, CA 94720, USA
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Noncanonical DNA Cleavage by BamHI Endonuclease in Laterally Confined DNA Monolayers Is a Step Function of DNA Density and Sequence. Molecules 2022; 27:molecules27165262. [PMID: 36014501 PMCID: PMC9416302 DOI: 10.3390/molecules27165262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/04/2022] [Accepted: 08/15/2022] [Indexed: 11/17/2022] Open
Abstract
Cleavage of DNA at noncanonical recognition sequences by restriction endonucleases (star activity) in bulk solution can be promoted by global experimental parameters, including enzyme or substrate concentration, temperature, pH, or buffer composition. To study the effect of nanoscale confinement on the noncanonical behaviour of BamHI, which cleaves a single unique sequence of 6 bp, we used AFM nanografting to generate laterally confined DNA monolayers (LCDM) at different densities, either in the form of small patches, several microns in width, or complete monolayers of thiol-modified DNA on a gold surface. We focused on two 44-bp DNAs, each containing a noncanonical BamHI site differing by 2 bp from the cognate recognition sequence. Topographic AFM imaging was used to monitor end-point reactions by measuring the decrease in the LCDM height with respect to the surrounding reference surface. At low DNA densities, BamHI efficiently cleaves only its cognate sequence while at intermediate DNA densities, noncanonical sequence cleavage occurs, and can be controlled in a stepwise (on/off) fashion by varying the DNA density and restriction site sequence. This study shows that endonuclease action on noncanonical sites in confined nanoarchitectures can be modulated by varying local physical parameters, independent of global chemical parameters.
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7
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Mechanisms and Biological Roles of DNA Methyltransferases and DNA Methylation: From Past Achievements to Future Challenges. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1389:1-19. [DOI: 10.1007/978-3-031-11454-0_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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8
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Yang H, Peng Y, Xu M, Xu S, Zhou Y. Development of DNA Biosensors Based on DNAzymes and Nucleases. Crit Rev Anal Chem 2021; 53:161-176. [PMID: 34225516 DOI: 10.1080/10408347.2021.1944046] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
DNA biosensors play important roles in environmental, medical, industrial and agricultural analysis. Many DNA biosensors have been designed based on the enzyme catalytic reaction. Because of the importance of enzymes in biosensors, we present a review on this topic. In this review, the enzymes were divided into DNAzymes and nucleases according to their chemical nature. Firstly, we introduced the DNAzymes with different function inducing cleavage, metalation, peroxidase, ligation and allosterism. In this section, the G-quadruplex DNAzyme, as a hot topic in recent years, was described in detail. Then, the nucleases-assisted signal amplification method was also reviewed in three categories including exonucleases, endonucleases and other nucleases according to the digestion sites in DNA substrates. In exonucleases section, the Exo I and Exo III were selected as examples. Then, the DNase I, BamH I, nicking endonuclease, S1 nuclease, the duplex specific nuclease (DSN) and RNases were chosen to illustrate the application of endonucleases. In other nucleases section, DNA polymerases and DNA ligases were detailed. Last, the challenges and future perspectives in the field were discussed.
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Affiliation(s)
- Hualin Yang
- College of Life Science, Yangtze University, Jingzhou, Hubei, China.,State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil &Water Pollution, Chengdu University of Technology, Chengdu, Sichuan, China
| | - Yu Peng
- College of Life Science, Yangtze University, Jingzhou, Hubei, China
| | - Mingming Xu
- College of Life Science, Yangtze University, Jingzhou, Hubei, China
| | - Shuxia Xu
- State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil &Water Pollution, Chengdu University of Technology, Chengdu, Sichuan, China.,College of Ecology and Environment, Chengdu University of Technology, Chengdu, Sichuan, China
| | - Yu Zhou
- College of Life Science, Yangtze University, Jingzhou, Hubei, China.,College of Animal Science, Yangtze University, Jingzhou, Hubei, China
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9
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Das B, Banerjee K, Gangopadhyay G. On the Role of Magnesium Ions in the DNA-Scissoring Activity of the Restriction Endonuclease ApaI: Stochastic Kinetics from a Single Molecule to Mesoscopic Paradigm. J Phys Chem B 2021; 125:4099-4107. [PMID: 33861609 DOI: 10.1021/acs.jpcb.0c10643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Biochemical reactions occurring inside cells have significant stochastic signatures due to the low copy number of reacting species. Kinetics of DNA cleavage by restriction endonucleases are no exception as established by single-molecule experiments. Here, we propose a simple reaction scheme to understand the role of the cofactor magnesium ion in the action of the endonuclease ApaI. The methodology is based on the waiting time distribution of cleavage product formation that enables us to determine the corresponding rate both analytically and numerically. The theory is developed at the single-molecule level and then generalized to the biologically relevant case of a population of DNA-endonuclease complexes present inside a cell. The theoretical rate versus cofactor concentration curve is matched with relevant single-molecule experimental data that reveals positive cooperativity of cofactor binding and provides a reliable estimate of model parameters. Furthermore, a parameter range is identified where the dispersion of the waiting time, measured using the coefficient of variation, is significantly lower than the Poisson limit and becomes minimum at the in vivo magnesium ion concentration level. Such low dispersion can play a role in the robust DNA-scissoring activity of ApaI under in vivo conditions.
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Affiliation(s)
- Biswajit Das
- S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake City, Kolkata 700106, India
| | - Kinshuk Banerjee
- Department of Chemistry, Acharya Jagadish Chandra Bose College, Kolkata 700020, India
| | - Gautam Gangopadhyay
- S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake City, Kolkata 700106, India
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Mo F, Jiang K, Zhao D, Wang Y, Song J, Tan W. DNA hydrogel-based gene editing and drug delivery systems. Adv Drug Deliv Rev 2021; 168:79-98. [PMID: 32712197 DOI: 10.1016/j.addr.2020.07.018] [Citation(s) in RCA: 122] [Impact Index Per Article: 40.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 06/12/2020] [Accepted: 07/21/2020] [Indexed: 12/20/2022]
Abstract
Deoxyribonucleic acid (DNA) is a promising synthesizer for precisely constructing almost arbitrary geometry in two and three dimensions. Among various DNA-based soft materials, DNA hydrogels are comprised of hydrophilic polymeric networks of crosslinked DNA chains. For their properties of biocompatibility, porosity, sequence programmability and tunable multifunctionality, DNA hydrogels have been widely studied in bioanalysis and biomedicine. In this review, recent developments in DNA hydrogels and their applications in drug delivery systems are highlighted. First, physical and chemical crosslinking methods for constructing DNA hydrogels are introduced. Subsequently, responses of DNA hydrogels to nonbiological and biological stimuli are described. Finally, DNA hydrogel-based delivery platforms for different types of drugs are detailed. With the emergence of gene therapy, this review also gives future prospects for combining DNA hydrogels with the gene editing toolbox.
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Ferreira RM, Ware AD, Matozel E, Price AC. Salt concentration modulates the DNA target search strategy of NdeI. Biochem Biophys Res Commun 2020; 534:1059-1063. [PMID: 33121681 DOI: 10.1016/j.bbrc.2020.10.036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 10/14/2020] [Indexed: 11/29/2022]
Abstract
DNA target search is a key step in cellular transactions that access genomic information. How DNA binding proteins combine 3D diffusion, sliding and hopping into an overall search strategy remains poorly understood. Here we report the use of a single molecule DNA tethering method to characterize the target search kinetics of the type II restriction endonuclease NdeI. The measured search rate depends strongly on DNA length as well as salt concentration. Using roadblocks, we show that there are significant changes in the DNA sliding length over the salt concentrations in our study. To explain our results, we propose a model including cycles of 3D and 1D search in which salt concentration modulates the strategy by varying the length of DNA probed per 1D scan. At low salt NdeI makes a single non-specific encounter with DNA followed by an effective and complete 1D scan. At higher salt, NdeI must execute multiple cycles of target search due to the reduced efficacy of 1D search.
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Affiliation(s)
- Raquel M Ferreira
- Department of Biology, Emmanuel College, 400 the Fenway, Boston, MA, 02115, United States
| | - Anna D Ware
- Department of Biology, Emmanuel College, 400 the Fenway, Boston, MA, 02115, United States
| | - Emily Matozel
- Department of Biology, Emmanuel College, 400 the Fenway, Boston, MA, 02115, United States
| | - Allen C Price
- Department of Chemistry and Physics, Emmanuel College, 400 the Fenway, Boston, MA, 02115, United States.
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12
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Lim Y, Bak SY, Lee SH, Kim SK. Comparative Single-Molecule Kinetic Study for the Effect of Base Methylation on a Model DNA-Protein Interaction. J Phys Chem Lett 2020; 11:8048-8052. [PMID: 32885977 DOI: 10.1021/acs.jpclett.0c01929] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We studied how the interaction between HindIII endonuclease and dsDNA is affected by the single-base modification of the latter by a single-molecule kinetic assay. For a comparative study of chemical modifications, we measured the binding and unbinding rates of the HindIII-DNA complex for normal dsDNA, methylated DNA, and hydroxymethylated DNA. We found that methylation of DNA at the recognition site results in a large increase in the unbinding rate due to the steric effect, which is consistent with the standard free energy change in the transition state. On the contrary, methylation minimally affects the binding rate, as simultaneous increases in the activation energy and the pre-exponential factor compensate for each other.
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Affiliation(s)
- Youngbin Lim
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - So Young Bak
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Sang Hak Lee
- Department of Chemistry, Pusan National University, Pusan 46241, Korea
| | - Seong Keun Kim
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
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13
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Matuszczak M, Spasibionek S, Gacek K, Bartkowiak-Broda I. Cleaved amplified polymorphic sequences (CAPS) marker for identification of two mutant alleles of the rapeseed BnaA.FAD2 gene. Mol Biol Rep 2020; 47:7607-7621. [PMID: 32979163 PMCID: PMC7588397 DOI: 10.1007/s11033-020-05828-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Accepted: 09/07/2020] [Indexed: 11/30/2022]
Abstract
Two mutants of winter rapeseed (Brassica napus L. var. oleifera) with an increased amount of oleic acid in seeds were created by chemical mutagenesis (HOR3-M10453 and HOR4-M10464). The overall performance of the mutated plants was much lower than that of wild-type cultivars. Multiple rounds of crossing with high-yielding double-low ("00") cultivars and breeding lines having valuable agronomic traits, followed by selection of high oleic acid genotypes is then needed to obtain new "00" varieties of rapeseed having high oleic acid content in seeds. To perform such selection, the specific codominant cleaved amplified polymorphic sequences (CAPS) marker was used. This marker was designed to detect the presence of two relevant point mutations in the desaturase gene BnaA.FAD2, and it was previously described and patented. The specific polymerase chain reaction product (732 bp) was digested using FspBI restriction enzyme that recognizes the 5'-C↓TAG-3' sequence which is common to both mutated alleles, thereby yielding band patterns specific for those alleles. The method proposed in the patent was redesigned, adjusted to specific laboratory conditions, and thoroughly tested. Different DNA extraction protocols were tested to optimize the procedure. Two variants of the CAPS method (with and without purification of amplified product) were considered to choose the best option. In addition, the ability of the studied marker to detect heterozygosity in the BnaA.FAD2 locus was also tested. Finally, we also presented some examples for the use of the new CAPS marker in the marker-assisted selection (MAS) during our breeding programs. The standard CTAB method of DNA extraction and the simplified, two-step (amplification/digestion) procedure for the CAPS marker are recommended. The marker was found to be useful for the detection of two mutated alleles of the studied BnaA.FAD2 desaturase gene and can potentially assure the breeders of the purity of their HOLL lines. However, it was also shown that it could not detect any other alleles or genes that were revealed to play a role in the regulation of oleic acid level.
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Affiliation(s)
- Marcin Matuszczak
- Research Division in Poznań, Plant Breeding and Acclimatization Institute, National Research Institute, Strzeszyńska 36, Poznań, Poland.
| | - Stanisław Spasibionek
- Research Division in Poznań, Plant Breeding and Acclimatization Institute, National Research Institute, Strzeszyńska 36, Poznań, Poland
| | - Katarzyna Gacek
- Research Division in Poznań, Plant Breeding and Acclimatization Institute, National Research Institute, Strzeszyńska 36, Poznań, Poland
| | - Iwona Bartkowiak-Broda
- Research Division in Poznań, Plant Breeding and Acclimatization Institute, National Research Institute, Strzeszyńska 36, Poznań, Poland
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14
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Mandal SC, Maganti L, Mondal M, Chakrabarti J. Microscopic insight to specificity of metal ion cofactor in DNA cleavage by restriction endonuclease EcoRV. Biopolymers 2020; 111:e23396. [PMID: 32858776 DOI: 10.1002/bip.23396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 07/22/2020] [Accepted: 07/27/2020] [Indexed: 11/06/2022]
Abstract
Restriction endonucleases protect bacterial cells against bacteriophage infection by cleaving the incoming foreign DNA into fragments. In presence of Mg2+ ions, EcoRV is able to cleave the DNA but not in presence of Ca2+ , although the protein binds to DNA in presence of both metal ions. We make an attempt to understand this difference using conformational thermodynamics. We calculate the changes in conformational free energy and entropy of conformational degrees of freedom, like DNA base pair steps and dihedral angles of protein residues in Mg2+ (A)-EcoRV-DNA complex compared to Ca2+ (S)-EcoRV-DNA complex using all-atom molecular dynamics (MD) trajectories of the complexes. We find that despite conformational stability and order in both complexes, the individual degrees of freedom behave differently in the presence of two different metal ions. The base pairs in cleavage region are highly disordered in Ca2+ (S)-EcoRV-DNA compared to Mg2+ (A)-EcoRV-DNA. One of the acidic residues ASP90, coordinating to the metal ion in the vicinity of the cleavage site, is conformationally destabilized and disordered, while basic residue LYS92 gets conformational stability and order in Ca2+ (S) bound complex than in Mg2+ (A) bound complex. The enhanced fluctuations hinder placement of the metal ion in the vicinity of the scissile phosphate of DNA. Similar loss of conformational stability and order in the cleavage region is observed by the replacement of the metal ion. Considering the placement of the metal ion near scissile phosphate as requirement for cleavage action, our results suggest that the changes in conformational stability and order of the base pair steps and the protein residues lead to cofactor sensitivity of the enzyme. Our method based on fluctuations of microscopic conformational variables can be applied to understand enzyme activities in other protein-DNA systems.
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Affiliation(s)
- Sasthi Charan Mandal
- Department of Chemical, Biological and Macro-Molecular Sciences, S.N. Bose National Centre for Basic Sciences, Kolkata, India
| | - Lakshmi Maganti
- Computational Science Division, Saha Institute of Nuclear Physics, Kolkata, India
| | - Manas Mondal
- Shenzhen Bay Laboratory, Institute of Systems and Physical Biology, Shenzhen, China
| | - Jaydeb Chakrabarti
- Department of Chemical, Biological and Macro-Molecular Sciences, S.N. Bose National Centre for Basic Sciences, Kolkata, India.,Thematic Unit of Excellence on Computational Materials Science, and Technical Research Centre, S. N. Bose National Centre for Basic Sciences, Kolkata, India
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15
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Restriction Endonuclease-Based Assays for DNA Detection and Isothermal Exponential Signal Amplification. SENSORS 2020; 20:s20143873. [PMID: 32664471 PMCID: PMC7411786 DOI: 10.3390/s20143873] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 07/08/2020] [Accepted: 07/10/2020] [Indexed: 11/30/2022]
Abstract
Application of restriction endonuclease (REase) enzymes for specific detection of nucleic acids provides for high assay specificity, convenience and low cost. A direct restriction assay format is based on the specific enzymatic cleavage of a target–probe hybrid that is accompanied with the release of a molecular marker into the solution, enabling target quantification. This format has the detection limit in nanomolar range. The assay sensitivity is improved drastically to the attomolar level by implementation of exponential signal amplification that is based on a cascade of self-perpetuating restriction endonuclease reactions. The cascade is started by action of an amplification “trigger”. The trigger is immobilized through a target-specific probe. Upon the target probe hybridization followed with specific cleavage, the trigger is released into the reaction solution. The solution is then added to the assay amplification stage, and the free trigger induces cleavage of amplification probes, thus starting the self-perpetuating cascade of REase-catalyzed events. Continuous cleavage of new amplification probes leads to the exponential release of new triggers and rapid exponential signal amplification. The proposed formats exemplify a valid isothermal alternative to qPCR with similar sensitivity achieved at a fraction of the associated costs, time and labor. Advantages and challenges of the approach are discussed.
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16
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Li Z, Wang X, Xu D, Zhang D, Wang D, Dai X, Wang Q, Li Z, Gu Y, Ouyang W, Zhao S, Huang B, Gong J, Zhao J, Chen A, Shen Y, Dong Y, Zhang W, Xu X, Xu C, Jiang Y. DNB-based on-chip motif finding: A high-throughput method to profile different types of protein-DNA interactions. SCIENCE ADVANCES 2020; 6:eabb3350. [PMID: 32789179 PMCID: PMC7399529 DOI: 10.1126/sciadv.abb3350] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 06/17/2020] [Indexed: 06/11/2023]
Abstract
Here, we report a sensitive DocMF system that uses next-generation sequencing chips to profile protein-DNA interactions. Using DocMF, we successfully identified a variety of endonuclease recognition sites and the protospacer adjacent motif (PAM) sequences of different CRISPR systems. DocMF can simultaneously screen both 5' and 3' PAMs with high coverage. For SpCas9, we found noncanonical 5'-NAG-3' (~5%) and 5'-NGA-3' (~1.6%), in addition to its common PAMs, 5'-NGG-3' (~89.9%). More relaxed PAM sequences of two uncharacterized Cas endonucleases, VeCas9 and BvCas12a, were extensively characterized using DocMF. Moreover, we observed that dCas9, a DNA binding protein lacking endonuclease activity, preferably bound to the previously reported 5'-NGG-3' sequence. In summary, our studies demonstrate that DocMF is the first tool with the capacity to exhaustively assay both the binding and the cutting properties of different DNA binding proteins.
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Affiliation(s)
| | - Xiaojue Wang
- BGI-Shenzhen, Shenzhen 518083, China
- Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, People's Republic of China
| | | | - Dengwei Zhang
- BGI-Shenzhen, Shenzhen 518083, China
- Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, People's Republic of China
| | - Dan Wang
- BGI-Shenzhen, Shenzhen 518083, China
- Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, People's Republic of China
- Guangdong Provincial Key Laboratory of Genome Read and Write, Shenzhen 518120, China
| | - Xuechen Dai
- BGI-Shenzhen, Shenzhen 518083, China
- Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, People's Republic of China
| | - Qi Wang
- BGI-Shenzhen, Shenzhen 518083, China
- Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, People's Republic of China
| | - Zhou Li
- BGI-Shenzhen, Shenzhen 518083, China
| | - Ying Gu
- BGI-Shenzhen, Shenzhen 518083, China
| | | | - Shuchang Zhao
- BGI-Shenzhen, Shenzhen 518083, China
- School of Basic Medicine, Qingdao University, Qingdao 266000, China
| | - Baoqian Huang
- BGI-Shenzhen, Shenzhen 518083, China
- School of Bioscience and Bioengineering, South China University of Technology, Guangzhou 510006, China
| | - Jian Gong
- Complete Genomics Inc., 2904 Orchard Pkwy, San Jose, CA 95134, USA
| | - Jing Zhao
- BGI-Shenzhen, Shenzhen 518083, China
| | - Ao Chen
- BGI-Shenzhen, Shenzhen 518083, China
| | - Yue Shen
- Guangdong Provincial Key Laboratory of Genome Read and Write, Shenzhen Engineering Laboratory for Innovative Molecular Diagnostics, BGI-ShenzhenShenzhen 518083, China
- Guangdong Provincial Academician Workstation of BGI Synthetic Genomics, BGI-Shenzhen, Shenzhen, 518083, China
| | | | | | - Xun Xu
- BGI-Shenzhen, Shenzhen 518083, China
- Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, People's Republic of China
- Guangdong Provincial Key Laboratory of Genome Read and Write, Shenzhen 518120, China
| | - Chongjun Xu
- BGI-Shenzhen, Shenzhen 518083, China
- Complete Genomics Inc., 2904 Orchard Pkwy, San Jose, CA 95134, USA
- MGI, BGI-Shenzhen, Shenzhen 518083, China
| | - Yuan Jiang
- BGI-Shenzhen, Shenzhen 518083, China
- Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, People's Republic of China
- Complete Genomics Inc., 2904 Orchard Pkwy, San Jose, CA 95134, USA
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17
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Subramanian H, Gatenby RA. Evolutionary advantage of anti-parallel strand orientation of duplex DNA. Sci Rep 2020; 10:9883. [PMID: 32555277 PMCID: PMC7303137 DOI: 10.1038/s41598-020-66705-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Accepted: 05/22/2020] [Indexed: 11/09/2022] Open
Abstract
DNA in all living systems shares common properties that are remarkably well suited to its function, suggesting refinement by evolution. However, DNA also shares some counter-intuitive properties which confer no obvious benefit, such as strand directionality and anti-parallel strand orientation, which together result in the complicated lagging strand replication. The evolutionary dynamics that led to these properties of DNA remain unknown but their universality suggests that they confer as yet unknown selective advantage to DNA. In this article, we identify an evolutionary advantage of anti-parallel strand orientation of duplex DNA, within a given set of plausible premises. The advantage stems from the increased rate of replication, achieved by dividing the DNA into predictable, independently and simultaneously replicating segments, as opposed to sequentially replicating the entire DNA, thereby parallelizing the replication process. We show that anti-parallel strand orientation is essential for such a replicative organization of DNA, given our premises, the most important of which is the assumption of the presence of sequence-dependent asymmetric cooperativity in DNA.
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Affiliation(s)
| | - Robert A Gatenby
- Integrated Mathematical Oncology Department, Cancer Biology and Evolution Program, H. Lee Moffitt Cancer Center and Research Institute, 12902, USF Magnolia Dr, Tampa, Florida, USA
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18
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Rational development of transformation in Clostridium thermocellum ATCC 27405 via complete methylome analysis and evasion of native restriction-modification systems. J Ind Microbiol Biotechnol 2019; 46:1435-1443. [PMID: 31342224 PMCID: PMC6791906 DOI: 10.1007/s10295-019-02218-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Accepted: 07/11/2019] [Indexed: 12/13/2022]
Abstract
A major barrier to both metabolic engineering and fundamental biological studies is the lack of genetic tools in most microorganisms. One example is Clostridium thermocellum ATCC 27405T, where genetic tools are not available to help validate decades of hypotheses. A significant barrier to DNA transformation is restriction–modification systems, which defend against foreign DNA methylated differently than the host. To determine the active restriction–modification systems in this strain, we performed complete methylome analysis via single-molecule, real-time sequencing to detect 6-methyladenine and 4-methylcytosine and the rarely used whole-genome bisulfite sequencing to detect 5-methylcytosine. Multiple active systems were identified, and corresponding DNA methyltransferases were expressed from the Escherichia coli chromosome to mimic the C. thermocellum methylome. Plasmid methylation was experimentally validated and successfully electroporated into C. thermocellum ATCC 27405. This combined approach enabled genetic modification of the C. thermocellum-type strain and acts as a blueprint for transformation of other non-model microorganisms.
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19
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Pikin SA, Pikina ES. On DNA Motions under Action of Enzymes of Different Types. II. CRYSTALLOGR REP+ 2019. [DOI: 10.1134/s106377451901019x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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20
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21
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Rosa J, Fernandez-Gonzalez E, Ducani C, Högberg B. BtsCI and BseGI display sequence preference in the nucleotides flanking the recognition sequence. PLoS One 2018; 13:e0202057. [PMID: 30118487 PMCID: PMC6097692 DOI: 10.1371/journal.pone.0202057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 07/26/2018] [Indexed: 12/31/2022] Open
Abstract
Restriction enzymes are the bread and butter of Molecular Biology. Nonetheless, how restriction enzymes recognize and cleave their target is not always clear. When developing a method for the enzymatic production of oligonucleotides, we noticed that type II endonucleases BtsCI and BseGI, which recognize the sequence GGATGNN^, perform incomplete digestions of DNA hairpins, with the top strand nick not always occurring correctly. We tested the cutting of synthetic hairpins containing all possible combinations of dinucleotides following the recognition site and our results show that all sequences containing one adenine following GGATG were digested more efficiently. We further show that the same sequence preference is also observable in double stranded DNA at higher Mg2+ concentrations and even in optimal conditions. Kinetic results show that BtsCI has a noteworthy difference in the first-rate constants between different sequences and between the two catalytic domains. An increase in Mg2+ resulted in a drastic decrease in the catalytic activity of the top (sense) strand that wasn’t always accompanied by a nick in the bottom strand (antisense).
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Affiliation(s)
- João Rosa
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | | | - Cosimo Ducani
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Björn Högberg
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- * E-mail:
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22
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Grayson KJ, Anderson JR. The ascent of man(made oxidoreductases). Curr Opin Struct Biol 2018; 51:149-155. [PMID: 29754103 PMCID: PMC6227378 DOI: 10.1016/j.sbi.2018.04.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 04/24/2018] [Indexed: 11/09/2022]
Abstract
Though established 40 years ago, the field of de novo protein design has recently come of age, with new designs exhibiting an unprecedented level of sophistication in structure and function. With respect to catalysis, de novo enzymes promise to revolutionise the industrial production of useful chemicals and materials, while providing new biomolecules as plug-and-play components in the metabolic pathways of living cells. To this end, there are now de novo metalloenzymes that are assembled in vivo, including the recently reported C45 maquette, which can catalyse a variety of substrate oxidations with efficiencies rivalling those of closely related natural enzymes. Here we explore the successful design of this de novo enzyme, which was designed to minimise the undesirable complexity of natural proteins using a minimalistic bottom-up approach.
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Affiliation(s)
- Katie J Grayson
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, BS8 1TD, UK
| | - Jl Ross Anderson
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, BS8 1TD, UK; BrisSynBio Synthetic Biology Research Centre, Life Sciences Building, University of Bristol, Tyndall Avenue, Bristol BS8 1TQ, UK.
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23
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Jeltsch A. From Bioengineering to CRISPR/Cas9 - A Personal Retrospective of 20 Years of Research in Programmable Genome Targeting. Front Genet 2018; 9:5. [PMID: 29434619 PMCID: PMC5790776 DOI: 10.3389/fgene.2018.00005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 01/04/2018] [Indexed: 12/03/2022] Open
Abstract
Genome targeting of restriction enzymes and DNA methyltransferases has many important applications including genome and epigenome editing. 15–20 years ago, my group was involved in the development of approaches for programmable genome targeting, aiming to connect enzymes with an oligodeoxynucleotide (ODN), which could form a sequence-specific triple helix at the genomic target site. Importantly, the target site of such enzyme-ODN conjugate could be varied simply by altering the ODN sequence promising great applicative values. However, this approach was facing many problems including the preparation and purification of the enzyme-ODN conjugates, their efficient delivery into cells, slow kinetics of triple helix formation and the requirement of a poly-purine target site sequence. Hence, for several years genome and epigenome editing approaches mainly were based on Zinc fingers and TAL proteins as targeting devices. More recently, CRISPR/Cas systems were discovered, which use a bound RNA for genome targeting that forms an RNA/DNA duplex with one DNA strand of the target site. These systems combine all potential advantages of the once imagined enzyme-ODN conjugates and avoid all main disadvantageous. Consequently, the application of CRISPR/Cas in genome and epigenome editing has exploded in recent years. We can draw two important conclusions from this example of research history. First, evolution still is the better bioengineer than humans and, whenever tested in parallel, natural solutions outcompete engineered ones. Second, CRISPR/Cas system were discovered in pure, curiosity driven, basic research, highlighting that it is basic, bottom-up research paving the way for fundamental innovation.
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Affiliation(s)
- Albert Jeltsch
- Department of Biochemistry, Institute of Biochemistry and Technical Biochemistry, University of Stuttgart, Stuttgart, Germany
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24
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Toliusis P, Zaremba M, Silanskas A, Szczelkun MD, Siksnys V. CgII cleaves DNA using a mechanism distinct from other ATP-dependent restriction endonucleases. Nucleic Acids Res 2017; 45:8435-8447. [PMID: 28854738 PMCID: PMC5737866 DOI: 10.1093/nar/gkx580] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 06/28/2017] [Indexed: 01/10/2023] Open
Abstract
The restriction endonuclease CglI from Corynebacterium glutamicum recognizes an asymmetric 5′-GCCGC-3′ site and cleaves the DNA 7 and 6/7 nucleotides downstream on the top and bottom DNA strands, respectively, in an NTP-hydrolysis dependent reaction. CglI is composed of two different proteins: an endonuclease (R.CglI) and a DEAD-family helicase-like ATPase (H.CglI). These subunits form a heterotetrameric complex with R2H2 stoichiometry. However, the R2H2·CglI complex has only one nuclease active site sufficient to cut one DNA strand suggesting that two complexes are required to introduce a double strand break. Here, we report studies to evaluate the DNA cleavage mechanism of CglI. Using one- and two-site circular DNA substrates we show that CglI does not require two sites on the same DNA for optimal catalytic activity. However, one-site linear DNA is a poor substrate, supporting a mechanism where CglI complexes must communicate along the one-dimensional DNA contour before cleavage is activated. Based on experimental data, we propose that adenosine triphosphate (ATP) hydrolysis by CglI produces translocation on DNA preferentially in a downstream direction from the target, although upstream translocation is also possible. Our results are consistent with a mechanism of CglI action that is distinct from that of other ATP-dependent restriction-modification enzymes.
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Affiliation(s)
- Paulius Toliusis
- Department of Protein-DNA Interactions, Institute of Biotechnology, Vilnius University, Sauletekio al. 7, LT-10257, Vilnius, Lithuania
| | - Mindaugas Zaremba
- Department of Protein-DNA Interactions, Institute of Biotechnology, Vilnius University, Sauletekio al. 7, LT-10257, Vilnius, Lithuania
| | - Arunas Silanskas
- Department of Protein-DNA Interactions, Institute of Biotechnology, Vilnius University, Sauletekio al. 7, LT-10257, Vilnius, Lithuania
| | - Mark D Szczelkun
- DNA-Protein Interactions Unit, School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol, BS8 1TD, UK
| | - Virginijus Siksnys
- Department of Protein-DNA Interactions, Institute of Biotechnology, Vilnius University, Sauletekio al. 7, LT-10257, Vilnius, Lithuania
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25
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Liu K, Wessler SR. Transposition of Mutator-like transposable elements (MULEs) resembles hAT and Transib elements and V(D)J recombination. Nucleic Acids Res 2017; 45:6644-6655. [PMID: 28482040 PMCID: PMC5499845 DOI: 10.1093/nar/gkx357] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 04/13/2017] [Accepted: 04/20/2017] [Indexed: 12/11/2022] Open
Abstract
Mutator-like transposable elements (MULEs) are widespread across fungal, plant and animal species. Despite their abundance and importance as genetic tools in plants, the transposition mechanism of the MULE superfamily was previously unknown. Discovery of the Muta1 element from Aedes aegypti and its successful transposition in yeast facilitated the characterization of key steps in Muta1 transposition. Here we show that purified transposase binds specifically to the Muta1 ends and catalyzes excision through double strand breaks (DSB) and the joining of newly excised transposon ends with target DNA. In the process, the DSB forms hairpin intermediates on the flanking DNA side. Analysis of transposase proteins containing site-directed mutations revealed the importance of the conserved DDE motif and a W residue. The transposition pathway resembles that of the V(D)J recombination reaction and the mechanism of hAT and Transib transposases including the importance of the conserved W residue in both MULEs and hATs. In addition, yeast transposition and in vitro assays demonstrated that the terminal motif and subterminal repeats of the Muta1 terminal inverted repeat also influence Muta1 transposition. Collectively, our data provides new insights to understand the evolutionary relationships between MULE, hAT and Transib elements and the V(D)J recombinase.
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Affiliation(s)
- Kun Liu
- Graduate program in Botany and Plant Sciences, University of California, Riverside, CA 92521, USA
| | - Susan R. Wessler
- Department of Botany and Plant Sciences, University of California, Riverside, CA 92521, USA
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26
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Yang X, Tang Y, Mason SD, Chen J, Li F. Enzyme-Powered Three-Dimensional DNA Nanomachine for DNA Walking, Payload Release, and Biosensing. ACS NANO 2016; 10:2324-30. [PMID: 26785347 DOI: 10.1021/acsnano.5b07102] [Citation(s) in RCA: 254] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Herein, we report a DNA nanomachine, built from a DNA-functionalized gold nanoparticle (DNA-AuNP), which moves a DNA walker along a three-dimensional (3-D) DNA-AuNP track and executes the task of releasing payloads. The movement of the DNA walker is powered by a nicking endonuclease that cleaves specific DNA substrates on the track. During the movement, each DNA walker cleaves multiple substrates, resulting in the rapid release of payloads (predesigned DNA sequences and their conjugates). The 3-D DNA nanomachine is highly efficient due to the high local effective concentrations of all DNA components that have been co-conjugated on the same AuNP. Moreover, the activity of the 3-D DNA nanomachine can be controlled by introducing a protecting DNA probe that can hybridize to or dehybridize from the DNA walker in a target-specific manner. This property allows us to tailor the DNA nanomachine into a DNA nanosensor that is able to achieve rapid, isothermal, and homogeneous signal amplification for specific nucleic acids in both buffer and a complicated biomatrix.
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Affiliation(s)
- Xiaolong Yang
- Department of Chemistry, Centre for Biotechnology, Brock University , St. Catharines, Ontario, Canada L2S3A1
| | - Yanan Tang
- Department of Chemistry, Centre for Biotechnology, Brock University , St. Catharines, Ontario, Canada L2S3A1
| | - Sean D Mason
- Department of Chemistry, Centre for Biotechnology, Brock University , St. Catharines, Ontario, Canada L2S3A1
| | - Junbo Chen
- Analytical & Testing Center, Sichuan University , Chengdu, Sichuan 610064, China
| | - Feng Li
- Department of Chemistry, Centre for Biotechnology, Brock University , St. Catharines, Ontario, Canada L2S3A1
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27
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Jurkowska RZ, Jeltsch A. Mechanisms and Biological Roles of DNA Methyltransferases and DNA Methylation: From Past Achievements to Future Challenges. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 945:1-17. [DOI: 10.1007/978-3-319-43624-1_1] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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28
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Li H, Endutkin AV, Bergonzo C, Campbell AJ, de los Santos C, Grollman A, Zharkov DO, Simmerling C. A dynamic checkpoint in oxidative lesion discrimination by formamidopyrimidine-DNA glycosylase. Nucleic Acids Res 2015; 44:683-94. [PMID: 26553802 PMCID: PMC4737139 DOI: 10.1093/nar/gkv1092] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 10/08/2015] [Indexed: 01/29/2023] Open
Abstract
In contrast to proteins recognizing small-molecule ligands, DNA-dependent enzymes cannot rely solely on interactions in the substrate-binding centre to achieve their exquisite specificity. It is widely believed that substrate recognition by such enzymes involves a series of conformational changes in the enzyme-DNA complex with sequential gates favoring cognate DNA and rejecting nonsubstrates. However, direct evidence for such mechanism is limited to a few systems. We report that discrimination between the oxidative DNA lesion, 8-oxoguanine (oxoG) and its normal counterpart, guanine, by the repair enzyme, formamidopyrimidine-DNA glycosylase (Fpg), likely involves multiple gates. Fpg uses an aromatic wedge to open the Watson-Crick base pair and everts the lesion into its active site. We used molecular dynamics simulations to explore the eversion free energy landscapes of oxoG and G by Fpg, focusing on structural and energetic details of oxoG recognition. The resulting energy profiles, supported by biochemical analysis of site-directed mutants disturbing the interactions along the proposed path, show that Fpg selectively facilitates eversion of oxoG by stabilizing several intermediate states, helping the rapidly sliding enzyme avoid full extrusion of every encountered base for interrogation. Lesion recognition through multiple gating intermediates may be a common theme in DNA repair enzymes.
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Affiliation(s)
- Haoquan Li
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794, USA
| | - Anton V Endutkin
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., Novosibirsk 630090, Russia Novosibirsk State University, 2 Pirogova St., Novosibirsk 630090, Russia
| | - Christina Bergonzo
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794, USA
| | - Arthur J Campbell
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794, USA
| | - Carlos de los Santos
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY 11794, USA
| | - Arthur Grollman
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY 11794, USA
| | - Dmitry O Zharkov
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., Novosibirsk 630090, Russia Novosibirsk State University, 2 Pirogova St., Novosibirsk 630090, Russia
| | - Carlos Simmerling
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794, USA Department of Chemistry, Stony Brook University, Stony Brook, NY 11794, USA
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29
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Wons E, Mruk I, Kaczorowski T. Relaxed specificity of prokaryotic DNA methyltransferases results in DNA site-specific modification of RNA/DNA heteroduplexes. J Appl Genet 2015; 56:539-546. [PMID: 25787880 DOI: 10.1007/s13353-015-0279-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 02/27/2015] [Accepted: 03/02/2015] [Indexed: 01/18/2023]
Abstract
RNA/DNA hybrid duplexes regularly occur in nature, for example in transcriptional R loops. Their susceptibility to modification by DNA-specific or RNA-specific enzymes is, thus, a biologically relevant question, which, in addition, has possible biotechnological implications. In this study, we investigated the activity of four isospecific DNA methyltransferases (M.EcoVIII, M.LlaCI, M.HindIII, M.BstZ1II) toward an RNA/DNA duplex carrying one 5'-AAGCUU-3'/3'-TTCGAA-5' target sequence. The analyzed enzymes belong to the β-group of adenine N6-methyltransferases and recognize the palindromic DNA sequence 5'-AAGCTT-3'/3'-TTCGAA-5'. Under standard conditions, none of these isospecific enzymes could detectibly methylate the RNA/DNA duplex. However, the addition of agents that generally relax specificity, such as dimethyl sulfoxide (DMSO) and glycerol, resulted in substantial methylation of the RNA/DNA duplex by M.EcoVIII and M.LlaCI. Only the DNA strand of the RNA/DNA duplex was methylated. The same was not observed for M.HindIII or M.BstZ1II. This is, to our knowledge, the first report that demonstrates such activity by prokaryotic DNA methyltransferases. Possible applications of these findings in a laboratory practice are also discussed.
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Affiliation(s)
- Ewa Wons
- Department of Microbiology, University of Gdansk, Wita Stwosza 59, 80-308, Gdansk, Poland
| | - Iwona Mruk
- Department of Microbiology, University of Gdansk, Wita Stwosza 59, 80-308, Gdansk, Poland
| | - Tadeusz Kaczorowski
- Department of Microbiology, University of Gdansk, Wita Stwosza 59, 80-308, Gdansk, Poland.
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30
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Lundin S, Jemt A, Terje-Hegge F, Foam N, Pettersson E, Käller M, Wirta V, Lexow P, Lundeberg J. Endonuclease specificity and sequence dependence of type IIS restriction enzymes. PLoS One 2015; 10:e0117059. [PMID: 25629514 PMCID: PMC4309577 DOI: 10.1371/journal.pone.0117059] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 12/17/2014] [Indexed: 11/23/2022] Open
Abstract
Restriction enzymes that recognize specific sequences but cleave unknown sequence outside the recognition site are extensively utilized tools in molecular biology. Despite this, systematic functional categorization of cleavage performance has largely been lacking. We established a simple and automatable model system to assay cleavage distance variation (termed slippage) and the sequence dependence thereof. We coupled this to massively parallel sequencing in order to provide sensitive and accurate measurement. With this system 14 enzymes were assayed (AcuI, BbvI, BpmI, BpuEI, BseRI, BsgI, Eco57I, Eco57MI, EcoP15I, FauI, FokI, GsuI, MmeI and SmuI). We report significant variation of slippage ranging from 1–54%, variations in sequence context dependence, as well as variation between isoschizomers. We believe this largely overlooked property of enzymes with shifted cleavage would benefit from further large scale classification and engineering efforts seeking to improve performance. The gained insights of in-vitro performance may also aid the in-vivo understanding of these enzymes.
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Affiliation(s)
- Sverker Lundin
- Science for Life Laboratory, KTH, Gene Technology, Solna, 171 65, Sweden
| | - Anders Jemt
- Science for Life Laboratory, KTH, Gene Technology, Solna, 171 65, Sweden
| | | | | | | | | | | | | | - Joakim Lundeberg
- Science for Life Laboratory, KTH, Gene Technology, Solna, 171 65, Sweden
- * E-mail:
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31
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Schmidt HG, Sewitz S, Andrews SS, Lipkow K. An integrated model of transcription factor diffusion shows the importance of intersegmental transfer and quaternary protein structure for target site finding. PLoS One 2014; 9:e108575. [PMID: 25333780 PMCID: PMC4204827 DOI: 10.1371/journal.pone.0108575] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Accepted: 08/30/2014] [Indexed: 11/30/2022] Open
Abstract
We present a computational model of transcription factor motion that explains both the observed rapid target finding of transcription factors, and how this motion influences protein and genome structure. Using the Smoldyn software, we modelled transcription factor motion arising from a combination of unrestricted 3D diffusion in the nucleoplasm, sliding along the DNA filament, and transferring directly between filament sections by intersegmental transfer. This presents a fine-grain picture of the way in which transcription factors find their targets two orders of magnitude faster than 3D diffusion alone allows. Eukaryotic genomes contain sections of nucleosome free regions (NFRs) around the promoters; our model shows that the presence and size of these NFRs can be explained as their acting as antennas on which transcription factors slide to reach their targets. Additionally, our model shows that intersegmental transfer may have shaped the quaternary structure of transcription factors: sequence specific DNA binding proteins are unusually enriched in dimers and tetramers, perhaps because these allow intersegmental transfer, which accelerates target site finding. Finally, our model shows that a ‘hopping’ motion can emerge from 3D diffusion on small scales. This explains the apparently long sliding lengths that have been observed for some DNA binding proteins observed in vitro. Together, these results suggest that transcription factor diffusion dynamics help drive the evolution of protein and genome structure.
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Affiliation(s)
- Hugo G. Schmidt
- Department of Biochemistry & Cambridge Systems Biology Centre, University of Cambridge, Cambridge, United Kingdom
- * E-mail: (HS); (KL)
| | - Sven Sewitz
- Department of Biochemistry & Cambridge Systems Biology Centre, University of Cambridge, Cambridge, United Kingdom
- Nuclear Dynamics Programme, The Babraham Institute, Cambridge, United Kingdom
| | - Steven S. Andrews
- Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Karen Lipkow
- Department of Biochemistry & Cambridge Systems Biology Centre, University of Cambridge, Cambridge, United Kingdom
- Nuclear Dynamics Programme, The Babraham Institute, Cambridge, United Kingdom
- * E-mail: (HS); (KL)
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32
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Pingoud A, Wilson GG, Wende W. Type II restriction endonucleases--a historical perspective and more. Nucleic Acids Res 2014; 42:7489-527. [PMID: 24878924 PMCID: PMC4081073 DOI: 10.1093/nar/gku447] [Citation(s) in RCA: 169] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Revised: 05/02/2014] [Accepted: 05/07/2014] [Indexed: 12/17/2022] Open
Abstract
This article continues the series of Surveys and Summaries on restriction endonucleases (REases) begun this year in Nucleic Acids Research. Here we discuss 'Type II' REases, the kind used for DNA analysis and cloning. We focus on their biochemistry: what they are, what they do, and how they do it. Type II REases are produced by prokaryotes to combat bacteriophages. With extreme accuracy, each recognizes a particular sequence in double-stranded DNA and cleaves at a fixed position within or nearby. The discoveries of these enzymes in the 1970s, and of the uses to which they could be put, have since impacted every corner of the life sciences. They became the enabling tools of molecular biology, genetics and biotechnology, and made analysis at the most fundamental levels routine. Hundreds of different REases have been discovered and are available commercially. Their genes have been cloned, sequenced and overexpressed. Most have been characterized to some extent, but few have been studied in depth. Here, we describe the original discoveries in this field, and the properties of the first Type II REases investigated. We discuss the mechanisms of sequence recognition and catalysis, and the varied oligomeric modes in which Type II REases act. We describe the surprising heterogeneity revealed by comparisons of their sequences and structures.
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Affiliation(s)
- Alfred Pingoud
- Institute of Biochemistry, Justus-Liebig-University Giessen, Heinrich-Buff-Ring 58, D-35392 Giessen, Germany
| | - Geoffrey G Wilson
- New England Biolabs Inc., 240 County Road, Ipswich, MA 01938-2723, USA
| | - Wolfgang Wende
- Institute of Biochemistry, Justus-Liebig-University Giessen, Heinrich-Buff-Ring 58, D-35392 Giessen, Germany
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33
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Wang GL, Luo HQ, Li NB. Gold nanorods-based FRET assay for ultrasensitive detection of DNA methylation and DNA methyltransferase activity. Analyst 2014; 139:4572-7. [DOI: 10.1039/c4an00206g] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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34
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Smith MW, Ghindilis AL, Seoudi IA, Smith K, Billharz R, Simon HM. A new restriction endonuclease-based method for highly-specific detection of DNA targets from methicillin-resistant Staphylococcus aureus. PLoS One 2014; 9:e97826. [PMID: 24831802 PMCID: PMC4022673 DOI: 10.1371/journal.pone.0097826] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 04/24/2014] [Indexed: 11/18/2022] Open
Abstract
PCR multiplexing has proven to be challenging, and thus has provided limited means for pathogen genotyping. We developed a new approach for analysis of PCR amplicons based on restriction endonuclease digestion. The first stage of the restriction enzyme assay is hybridization of a target DNA to immobilized complementary oligonucleotide probes that carry a molecular marker, horseradish peroxidase (HRP). At the second stage, a target-specific restriction enzyme is added, cleaving the target-probe duplex at the corresponding restriction site and releasing the HRP marker into solution, where it is quantified colorimetrically. The assay was tested for detection of the methicillin-resistant Staphylococcus aureus (MRSA) pathogen, using the mecA gene as a target. Calibration curves indicated that the limit of detection for both target oligonucleotide and PCR amplicon was approximately 1 nM. Sequences of target oligonucleotides were altered to demonstrate that (i) any mutation of the restriction site reduced the signal to zero; (ii) double and triple point mutations of sequences flanking the restriction site reduced restriction to 50–80% of the positive control; and (iii) a minimum of a 16-bp target-probe dsDNA hybrid was required for significant cleavage. Further experiments showed that the assay could detect the mecA amplicon from an unpurified PCR mixture with detection limits similar to those with standard fluorescence-based qPCR. Furthermore, addition of a large excess of heterologous genomic DNA did not affect amplicon detection. Specificity of the assay is very high because it involves two biorecognition steps. The proposed assay is low-cost and can be completed in less than 1 hour. Thus, we have demonstrated an efficient new approach for pathogen detection and amplicon genotyping in conjunction with various end-point and qPCR applications. The restriction enzyme assay may also be used for parallel analysis of multiple different amplicons from the same unpurified mixture in broad-range PCR applications.
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Affiliation(s)
- Maria W. Smith
- Center for Coastal Margin Observation & Prediction, and Institute of Environmental Health, Oregon Health & Science University, Portland, Oregon, United States of America
- Cascade Biosystems, Inc., Colfax, Wisconsin, United States of America
- * E-mail:
| | | | | | - Kenneth Smith
- Cascade Biosystems, Inc., Colfax, Wisconsin, United States of America
| | - Rosalind Billharz
- Pacific Lutheran University, Department of Biology, Tacoma, Washington, United States of America
| | - Holly M. Simon
- Center for Coastal Margin Observation & Prediction, and Institute of Environmental Health, Oregon Health & Science University, Portland, Oregon, United States of America
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Sawada T, Hisada H, Fujita M. Mutual induced fit in a synthetic host-guest system. J Am Chem Soc 2014; 136:4449-51. [PMID: 24611612 DOI: 10.1021/ja500376x] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Mutual induced fit is an important phenomenon in biological molecular recognition, but it is still rare in artificial systems. Here we report an artificial host-guest system in which a flexible calix[4]arene is enclathrated in a dynamic self-assembled host and both molecules mutually adopt specific three-dimensional structures. NMR data revealed the conformational changes, and crystallographic studies clearly established the precise structures at each stage.
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Affiliation(s)
- Tomohisa Sawada
- Department of Applied Chemistry, School of Engineering, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
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36
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Lyumkis D, Talley H, Stewart A, Shah S, Park CK, Tama F, Potter CS, Carragher B, Horton NC. Allosteric regulation of DNA cleavage and sequence-specificity through run-on oligomerization. Structure 2013; 21:1848-58. [PMID: 24055317 PMCID: PMC3898938 DOI: 10.1016/j.str.2013.08.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Revised: 08/08/2013] [Accepted: 08/09/2013] [Indexed: 10/26/2022]
Abstract
SgrAI is a sequence specific DNA endonuclease that functions through an unusual enzymatic mechanism that is allosterically activated 200- to 500-fold by effector DNA, with a concomitant expansion of its DNA sequence specificity. Using single-particle transmission electron microscopy to reconstruct distinct populations of SgrAI oligomers, we show that in the presence of allosteric, activating DNA, the enzyme forms regular, repeating helical structures characterized by the addition of DNA-binding dimeric SgrAI subunits in a run-on manner. We also present the structure of oligomeric SgrAI at 8.6 Å resolution, demonstrating the conformational state of SgrAI in its activated form. Activated and oligomeric SgrAI displays key protein-protein interactions near the helix axis between its N termini, as well as allosteric protein-DNA interactions that are required for enzymatic activation. The hybrid approach reveals an unusual mechanism of enzyme activation that explains SgrAI's oligomerization and allosteric behavior.
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Affiliation(s)
- Dmitry Lyumkis
- National Resource for Automated Molecular Microscopy, The Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, 92037
| | - Heather Talley
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, 85721
| | - Andrew Stewart
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, 85721
- Genetics Interdisciplinary Graduate Program, University of Arizona, Tucson, AZ, 85721
| | - Santosh Shah
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, 85721
| | - Chad K. Park
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, 85721
| | - Florence Tama
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, 85721
| | - Clinton S. Potter
- National Resource for Automated Molecular Microscopy, The Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, 92037
| | - Bridget Carragher
- National Resource for Automated Molecular Microscopy, The Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, 92037
| | - Nancy C. Horton
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, 85721
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37
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Khazanov N, Marcovitz A, Levy Y. Asymmetric DNA-search dynamics by symmetric dimeric proteins. Biochemistry 2013; 52:5335-44. [PMID: 23866074 DOI: 10.1021/bi400357m] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We focus on dimeric DNA-binding proteins from two well-studied families: orthodox type II restriction endonucleases (REs) and transcription factors (TFs). Interactions of the protein's recognition sites with the DNA and, particularly, the contribution of each of the monomers to one-dimensional (1D) sliding along nonspecific DNA were studied using computational tools. Coarse-grained molecular dynamics simulations of DNA scanning by various TFs and REs provide insights into how the symmetry of a homodimer can be broken while they nonspecifically interact with DNA. The characteristics of protein sliding along DNA, such as the average sliding length, partitioning between 1D and 3D search, and the one-dimensional diffusion coefficient D1, strongly depend on the salt concentration, which in turn affects the probability of the two monomers adopting a cooperative symmetric sliding mechanism. Indeed, we demonstrate that maximal DNA search efficiency is achieved when the protein adopts an asymmetric search mode in which one monomer slides while its partner hops. We find that proteins classified as TFs have a higher affinity for the DNA, longer sliding lengths, and an increased probability of symmetric sliding in comparison with REs. Moreover, TFs can perform their biological function over a much wider range of salt concentrations than REs. Our results demonstrate that the different biological functions of DNA-binding proteins are related to the different nonspecific DNA search mechanisms they adopt.
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Affiliation(s)
- Netaly Khazanov
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
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38
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Li S, Chen N, Zhang Z, Wang Y. Endonuclease-responsive aptamer-functionalized hydrogel coating for sequential catch and release of cancer cells. Biomaterials 2012; 34:460-9. [PMID: 23083933 DOI: 10.1016/j.biomaterials.2012.09.040] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Accepted: 09/17/2012] [Indexed: 01/09/2023]
Abstract
Rare circulating tumor cells are a promising biomarker for the detection, diagnosis, and monitoring of cancer. However, it remains a challenge to develop biomedical devices for specific catch and nondestructive release of circulating tumor cells. The purpose of this study was to explore a unique system for cell catch and release by using aptamer-functionalized hydrogels and restriction endonucleases. The results show that the hydrogel coating was highly resistant to nonspecific cell binding with ~5-15 cells/mm(2) on the hydrogel surface. In contrast, under the same condition, the aptamer-functionalized hydrogel coating could catch target cancer cells with a density over 1000 cells/mm(2). When the hydrogel coating was further treated with the restriction endonucleases, the bound cells were released from the hydrogel coating because of the endonuclease-mediated sequence-specific hydrolysis of the aptamer sequences. The release efficiency reached ~99%. Importantly, ~98% of the released cells maintained viability. Taken together, this study demonstrates that it is promising to apply endonuclease-responsive aptamer-functionalized hydrogels as a coating material to develop medical devices for specific catch and nondestructive release of rare circulating tumor cells.
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Affiliation(s)
- Shihui Li
- Program of Biomedical Engineering, School of Engineering, University of Connecticut, Storrs, CT 06269-3222, USA
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39
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Belkebir A, Azeddoug H. Metal ion dependence of DNA cleavage by SepMI and EhoI restriction endonucleases. Microbiol Res 2012; 168:99-105. [PMID: 23017231 DOI: 10.1016/j.micres.2012.08.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Revised: 07/04/2012] [Accepted: 08/12/2012] [Indexed: 10/27/2022]
Abstract
Most of type II restriction endonucleases show an absolute requirement for divalent metal ions as cofactors for DNA cleavage. While Mg(2+) is the natural cofactor other metal ions can substitute it and mediate the catalysis, however Ca(2+) (alone) only supports DNA binding. To investigate the role of Mg(2+) in DNA cleavage by restriction endonucleases, we have studied the Mg(2+) and Mn(2+) concentration dependence of DNA cleavage by SepMI and EhoI. Digestion reactions were carried out at different Mg(2+) and Mn(2+) concentrations at constant ionic strength. These enzymes showed different behavior regarding the ions requirement, SepMI reached near maximal level of activity between 10 and 20mM while no activity was detected in the presence of Mn(2+) and in the presence of Ca(2+) cleavage activity was significantly decreased. However, EhoI was more highly active in the presence of Mn(2+) than in the presence of Mg(2+) and can be activated by Ca(2+). Our results propose the two-metal ion mechanism for EhoI and the one-metal ion mechanism for SepMI restriction endonuclease. The analysis of the kinetic parameters under steady state conditions showed that SepMI had a K(m) value for pTrcHisB DNA of 6.15 nM and a V(max) of 1.79×10(-2)nM min(-1), while EhoI had a K(m) for pUC19 plasmid of 8.66 nM and a V(max) of 2×10(-2)nM min(-1).
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Affiliation(s)
- Abdelkarim Belkebir
- Laboratoire de Biochimie et de Biologie Moléculaire, Faculté des Sciences, Université Hassan II-Ain Chock - Casablanca, km 8, route d'El Jadida BP. 5366, Casablanca, Morocco.
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40
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Liu JJ, Song XR, Wang YW, Chen GN, Yang HH. A graphene oxide (GO)-based molecular beacon for DNA-binding transcription factor detection. NANOSCALE 2012; 4:3655-3659. [PMID: 22581162 DOI: 10.1039/c2nr30499f] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A GO-based molecular beacon assay was developed for rapid, sensitive and cost-efficient detection of transcription factor proteins. Furthermore, this assay can be employed for screening inhibitors of transcription factor proteins.
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Affiliation(s)
- Jing-Jing Liu
- The Key Lab of Analysis and Detection Technology for Food Safety of the MOE, College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350108, PR China
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41
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Zhukhlistova NE, Balaev VV, Lyashenko AV, Lashkov AA. Structural aspects of catalytic mechanisms of endonucleases and their binding to nucleic acids. CRYSTALLOGR REP+ 2012. [DOI: 10.1134/s1063774512030236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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42
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NYARKO ELVIS, TABATA MASAAKI. Interactions of tetracationic mercury(II), cadmium(II) and lead(II) porphyrins with DNA and their effects on DNA cleavage. J PORPHYR PHTHALOCYA 2012. [DOI: 10.1002/jpp.557] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The effects of tetrakis(1-methylpyridinium-4-yl)porphyrinatomercury(II) [ Hg ( TMPyP )]4+(6) along with [ Pb ( TMPyP )]4+(7), [ Cd ( TMPyP )]4+(8), and [ H2( TMPyP )]4+(1) (free base porphyrin) on DNA cleavage by Haemophilus aegyptius (HaeIII) have been studied using gel electrophoresis, UV-vis absorption spectroscopy, and circular dichroism (CD) spectroscopy. The gel electrophoresis results indicate that in the absence of 6, HaeIII restriction enzyme could not cleave plasmid DNA at a low concentration of 0.2 units μl-1after 1 h incubation at 37 °C. However, DNA cleavage occurred in the presence of 6 at the concentrations of 1.0 × 10-6and 1.0 × 10-7M and 0.2 units μl-1of HaeIII under the same conditions. In addition, acceleration of DNA cleavage occurred at a higher concentration of HaeIII (0.4 units μl-1) in the presence of a wider concentration range of 6 from 1.0 × 10-5to 1.0 × 10-7M . 8, 7, and 1 could not enhance DNA cleavage in the presence of HaeIII (0.2 units μl-1). However, when the concentration of HaeIII was increased to 0.4 units μl-1, only 8 inhibited DNA cleavage by HaeIII at higher concentrations (1.0 × 10-5-10-6M ) whereas 6, 7, and 1 did not. The UV-vis and CD spectroscopic results indicate that these porphyrins interact differently with DNA based on their binding modes. 6 enhanced DNA cleavage due to the synergistic effect of the Hg2+ions and the free base porphyrin 1 that dissociated from the mercury(II) porphyrin complex upon binding to DNA which resulted in the enhanced transformation of the DNA conformation from the original B-form to a Z-like conformation, while 8 inhibited HaeIII activity at higher concentrations and 7 and 1 neither enhanced nor inhibited DNA cleavage. A mechanism for this phenomenon is suggested.
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Affiliation(s)
- ELVIS NYARKO
- Department of Chemistry, Faculty of Science and Engineering, Saga University, 1 Honjo-machi, Saga 840-8502, Japan
| | - MASAAKI TABATA
- Department of Chemistry, Faculty of Science and Engineering, Saga University, 1 Honjo-machi, Saga 840-8502, Japan
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43
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Belkebir A, Azeddoug H. Characterization of LlaKI, a New Metal Ion-Independent Restriction Endonuclease from Lactococcus lactis KLDS4. ISRN BIOCHEMISTRY 2012; 2012:287230. [PMID: 25969755 PMCID: PMC4392985 DOI: 10.5402/2012/287230] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Accepted: 09/05/2012] [Indexed: 11/23/2022]
Abstract
Requirement of divalent cations for DNA cleavage is a general feature of type II restriction enzymes with the exception of few members of this group. A new type II restriction endonuclease has been partially purified from Lactococcus lactis KLDS4. The enzyme was denoted as LlaKI and showed to recognize and cleave the same site as FokI. The enzyme displayed a denatured molecular weight of 50 kDa and behaved as a dimer in solution as evidenced by the size exclusion chromatography. To investigate the role of divalent cations in DNA cleavage by LlaKI, digestion reactions were carried out at different Mg(2+), Mn(2+), and Ca(2+) concentrations. Unlike most of type II restriction endonucleases, LlaKI did not require divalent metal ions to cleave DNA and is one of the few metal-independent restriction endonucleases found in bacteria. The enzyme showed near-maximal levels of activity in 10 mM Tris-HCl pH 7.9, 50 mM NaCl, 10 mM MgCl2, and 1 mM dithiothreitol at 30°C. The presence of DNA modification was also determined and was correlated with the correspondent restriction enzyme.
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Affiliation(s)
- Abdelkarim Belkebir
- Laboratoire de Biochimie et Biologie Moléculaire, Faculté des Sciences, Université Hassan II-Ain Chock Casablanca, km 8, route d'El Jadida BP 5366, Casablanca, Morocco
| | - Houssine Azeddoug
- Laboratoire de Biochimie et Biologie Moléculaire, Faculté des Sciences, Université Hassan II-Ain Chock Casablanca, km 8, route d'El Jadida BP 5366, Casablanca, Morocco
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44
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Liu X, Ouyang L, Huang Y, Feng X, Fan Q, Huang W. Highly sensitive detection of DNA-binding proteins based on a cationic conjugated polymer via a target-mediated fluorescence resonance energy transfer (TMFRET) strategy. Polym Chem 2012. [DOI: 10.1039/c2py00499b] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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45
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Collier IE, Legant W, Marmer B, Lubman O, Saffarian S, Wakatsuki T, Elson E, Goldberg GI. Diffusion of MMPs on the surface of collagen fibrils: the mobile cell surface-collagen substratum interface. PLoS One 2011; 6:e24029. [PMID: 21912660 PMCID: PMC3164694 DOI: 10.1371/journal.pone.0024029] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Accepted: 08/01/2011] [Indexed: 11/18/2022] Open
Abstract
Remodeling of the extracellular matrix catalyzed by MMPs is central to morphogenetic phenomena during development and wound healing as well as in numerous pathologic conditions such as fibrosis and cancer. We have previously demonstrated that secreted MMP-2 is tethered to the cell surface and activated by MT1-MMP/TIMP-2-dependent mechanism. The resulting cell-surface collagenolytic complex (MT1-MMP)(2)/TIMP-2/MMP-2 can initiate (MT1-MMP) and complete (MMP-2) degradation of an underlying collagen fibril. The following question remained: What is the mechanism of substrate recognition involving the two structures of relatively restricted mobility, the cell surface enzymatic complex and a collagen fibril embedded in the ECM? Here we demonstrate that all the components of the complex are capable of processive movement on a surface of the collagen fibril. The mechanism of MT1-MMP movement is a biased diffusion with the bias component dependent on the proteolysis of its substrate, not adenosine triphosphate (ATP) hydrolysis. It is similar to that of the MMP-1 Brownian ratchet we described earlier. In addition, both MMP-2 and MMP-9 as well as their respective complexes with TIMP-1 and -2 are capable of Brownian diffusion on the surface of native collagen fibrils without noticeable dissociation while the dimerization of MMP-9 renders the enzyme immobile. Most instructive is the finding that the inactivation of the enzymatic activity of MT1-MMP has a detectable negative effect on the cell force developed in miniaturized 3D tissue constructs. We propose that the collagenolytic complex (MT1-MMP)(2)/TIMP-2/MMP-2 represents a Mobile Cell Surface-Collagen Substratum Interface. The biological implications of MT1-MMP acting as a molecular ratchet tethered to the cell surface in complex with MMP-2 suggest a new mechanism for the role of spatially regulated peri-cellular proteolysis in cell-matrix interactions.
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Affiliation(s)
- Ivan E. Collier
- Division of Dermatology, Department of Medicine, Washington University School of Medicine, Saint Louis, Missouri, United States of America
| | - Wesley Legant
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Barry Marmer
- Division of Dermatology, Department of Medicine, Washington University School of Medicine, Saint Louis, Missouri, United States of America
| | - Olga Lubman
- Department of Pathology, Washington University School of Medicine, Saint Louis, Missouri, United States of America
| | - Saveez Saffarian
- Department of Physics, University of Utah, Salt Lake City, Utah, United States of America
| | - Tetsuro Wakatsuki
- Department of Physiology, Biotechnology and Bioengineering Center, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Elliot Elson
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, Saint Louis, Missouri, United States of America
| | - Gregory I. Goldberg
- Division of Dermatology, Department of Medicine, Washington University School of Medicine, Saint Louis, Missouri, United States of America
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, Saint Louis, Missouri, United States of America
- * E-mail:
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46
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Belkebir A, Azeddoug H. Purification and characterization of SepII a new restriction endonuclease from Staphylococcus epidermidis. Microbiol Res 2011; 167:90-4. [PMID: 21511449 DOI: 10.1016/j.micres.2011.03.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2010] [Revised: 03/15/2011] [Accepted: 03/26/2011] [Indexed: 11/25/2022]
Abstract
A Type II restriction enzyme SepII has been purified to apparent homogeneity from the gram-positive coccus, Staphylococcus epidermidis. The purification included an ammonium sulfate precipitation followed by Q-sepharose, heparin-sepharose and MonoQ column chromatography on an FPLC system. SDS-PAGE analysis showed a denatured molecular weight of 29 kDa. The effects of temperature, pH, NaCl, Mn(2+), Ca(2+), and Mg(2+) ion concentrations were studied to determine the optimal reaction conditions. The enzyme exhibits near maximal levels of activity between pH 8-10, at 10-20mM MgCl(2), 100-150 mM NaCl and 1mM DTT. The results also show that in NEB Buffer 3 the enzyme is active over a broad temperature range from 0 to 70 °C, and in the absence of DNA, enzyme thermostability is observed up to 50 °C for 20 min, while most of the original activity is conserved in 50% glycerol for weeks at room temperature. Single and double digestion in presence of commercial restriction enzymes of known DNA substrates (lambda, pBR322, pET21, pTrcHisB, pPB67) showed that the purified SepII recognized and cleaved the same site as EcoRV. Genomic DNA modification status was also determined.
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Affiliation(s)
- Abdelkarim Belkebir
- Laboratoire de Biochimie et de Biologie Moléculaire, Faculté des Sciences, Université Hassan II-Ain Chock, Casablanca, km 8, route d'El Jadida BP. 5366, Casablanca, Morocco.
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Huang Y, Zhao S, Chen ZF, Liu YC, Liang H. Ultrasensitive endonuclease activity and inhibition detection using gold nanoparticle-enhanced fluorescence polarization. Chem Commun (Camb) 2011; 47:4763-5. [DOI: 10.1039/c1cc10325c] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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48
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López T, Figueras F, Manjarrez J, Bustos J, Alvarez M, Silvestre-Albero J, Rodríguez-Reinoso F, Martínez-Ferre A, Martínez E. Catalytic nanomedicine: A new field in antitumor treatment using supported platinum nanoparticles. In vitro DNA degradation and in vivo tests with C6 animal model on Wistar rats. Eur J Med Chem 2010; 45:1982-90. [PMID: 20153564 DOI: 10.1016/j.ejmech.2010.01.043] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2009] [Revised: 12/29/2009] [Accepted: 01/19/2010] [Indexed: 10/19/2022]
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49
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Langlois RE, Lu H. Boosting the prediction and understanding of DNA-binding domains from sequence. Nucleic Acids Res 2010; 38:3149-58. [PMID: 20156993 PMCID: PMC2879530 DOI: 10.1093/nar/gkq061] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
DNA-binding proteins perform vital functions related to transcription, repair and replication. We have developed a new sequence-based machine learning protocol to identify DNA-binding proteins. We compare our method with an extensive benchmark of previously published structure-based machine learning methods as well as a standard sequence alignment technique, BLAST. Furthermore, we elucidate important feature interactions found in a learned model and analyze how specific rules capture general mechanisms that extend across DNA-binding motifs. This analysis is carried out using the malibu machine learning workbench available at http://proteomics.bioengr.uic.edu/malibu and the corresponding data sets and features are available at http://proteomics.bioengr.uic.edu/dna.
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Affiliation(s)
- Robert E Langlois
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60612, USA
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50
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The phasevarion: phase variation of type III DNA methyltransferases controls coordinated switching in multiple genes. Nat Rev Microbiol 2010; 8:196-206. [PMID: 20140025 DOI: 10.1038/nrmicro2283] [Citation(s) in RCA: 133] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
In several host-adapted pathogens, phase variation has been found to occur in genes that encode methyltransferases associated with type III restriction-modification systems. It was recently shown that in the human pathogens Haemophilus influenzae, Neisseria gonorrhoeae and Neisseria meningitidis phase variation of a type III DNA methyltransferase, encoded by members of the mod gene family, regulates the expression of multiple genes. This novel genetic system has been termed the 'phasevarion' (phase-variable regulon). The wide distribution of phase-variable mod family genes indicates that this may be a common strategy used by host-adapted bacterial pathogens to randomly switch between distinct cell types.
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