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Wu M, Marchando P, Meyer K, Tang Z, Woolfson DN, Weiner OD. The WAVE complex forms linear arrays at negative membrane curvature to instruct lamellipodia formation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.08.600855. [PMID: 39026726 PMCID: PMC11257481 DOI: 10.1101/2024.07.08.600855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
Cells generate a wide range of actin-based membrane protrusions for various cell behaviors. These protrusions are organized by different actin nucleation promoting factors. For example, N-WASP controls finger-like filopodia, whereas the WAVE complex controls sheet-like lamellipodia. These different membrane morphologies likely reflect different patterns of nucleator self-organization. N-WASP phase separation has been successfully studied through biochemical reconstitutions, but how the WAVE complex self-organizes to instruct lamellipodia is unknown. Because WAVE complex self-organization has proven refractory to cell-free studies, we leverage in vivo biochemical approaches to investigate WAVE complex organization within its native cellular context. With single molecule tracking and molecular counting, we show that the WAVE complex forms highly regular multilayered linear arrays at the plasma membrane that are reminiscent of a microtubule-like organization. Similar to the organization of microtubule protofilaments in a curved array, membrane curvature is both necessary and sufficient for formation of these WAVE complex linear arrays, though actin polymerization is not. This dependency on negative membrane curvature could explain both the templating of lamellipodia and their emergent behaviors, including barrier avoidance. Our data uncover the key biophysical properties of mesoscale WAVE complex patterning and highlight an integral relationship between NPF self-organization and cell morphogenesis.
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Affiliation(s)
- Muziyue Wu
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
- Cardiovascular Research Institute,University of California San Francisco, San Francisco, CA, USA
| | - Paul Marchando
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA
| | - Kirstin Meyer
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
- Cardiovascular Research Institute,University of California San Francisco, San Francisco, CA, USA
| | - Ziqi Tang
- School of Computational Science and Engineering, Georgia Institute of Technology, Atlanta, GA
| | - Derek N Woolfson
- School of Chemistry, University of Bristol, Bristol, UK
- Max Planck-Bristol Centre for Minimal Biology, University of Bristol, Bristol, UK
- School of Biochemistry, University of Bristol, Biomedical Sciences Building, Bristol, UK
- Bristol BioDesign Institute, University of Bristol, Bristol, UK
| | - Orion D Weiner
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
- Cardiovascular Research Institute,University of California San Francisco, San Francisco, CA, USA
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2
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Saunders SH, Ahmed AM. ORBIT for E. coli: kilobase-scale oligonucleotide recombineering at high throughput and high efficiency. Nucleic Acids Res 2024; 52:e43. [PMID: 38587185 PMCID: PMC11077079 DOI: 10.1093/nar/gkae227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 02/28/2024] [Accepted: 03/19/2024] [Indexed: 04/09/2024] Open
Abstract
Microbiology and synthetic biology depend on reverse genetic approaches to manipulate bacterial genomes; however, existing methods require molecular biology to generate genomic homology, suffer from low efficiency, and are not easily scaled to high throughput. To overcome these limitations, we developed a system for creating kilobase-scale genomic modifications that uses DNA oligonucleotides to direct the integration of a non-replicating plasmid. This method, Oligonucleotide Recombineering followed by Bxb-1 Integrase Targeting (ORBIT) was pioneered in Mycobacteria, and here we adapt and expand it for Escherichia coli. Our redesigned plasmid toolkit for oligonucleotide recombineering achieved significantly higher efficiency than λ Red double-stranded DNA recombineering and enabled precise, stable knockouts (≤134 kb) and integrations (≤11 kb) of various sizes. Additionally, we constructed multi-mutants in a single transformation, using orthogonal attachment sites. At high throughput, we used pools of targeting oligonucleotides to knock out nearly all known transcription factor and small RNA genes, yielding accurate, genome-wide, single mutant libraries. By counting genomic barcodes, we also show ORBIT libraries can scale to thousands of unique members (>30k). This work demonstrates that ORBIT for E. coli is a flexible reverse genetic system that facilitates rapid construction of complex strains and readily scales to create sophisticated mutant libraries.
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Affiliation(s)
- Scott H Saunders
- Green Center for Systems Biology - Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75320, USA
| | - Ayesha M Ahmed
- Green Center for Systems Biology - Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75320, USA
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3
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Wang P, Du X, Zhao Y, Wang W, Cai T, Tang K, Wang X. Combining CRISPR/Cas9 and natural excision for the precise and complete removal of mobile genetic elements in bacteria. Appl Environ Microbiol 2024; 90:e0009524. [PMID: 38497640 PMCID: PMC11022536 DOI: 10.1128/aem.00095-24] [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: 01/19/2024] [Accepted: 02/23/2024] [Indexed: 03/19/2024] Open
Abstract
Horizontal gene transfer, facilitated by mobile genetic elements (MGEs), is an adaptive evolutionary process that contributes to the evolution of bacterial populations and infectious diseases. A variety of MGEs not only can integrate into the bacterial genome but also can survive or even replicate like plasmids in the cytoplasm, thus requiring precise and complete removal for studying their strategies in benefiting host cells. Existing methods for MGE removal, such as homologous recombination-based deletion and excisionase-based methods, have limitations in effectively eliminating certain MGEs. To overcome these limitations, we developed the Cas9-NE method, which combines the CRISPR/Cas9 system with the natural excision of MGEs. In this approach, a specialized single guide RNA (sgRNA) element is designed with a 20-nucleotide region that pairs with the MGE sequence. This sgRNA is expressed from a plasmid that also carries the Cas9 gene. By utilizing the Cas9-NE method, both the integrative and circular forms of MGEs can be precisely and completely eliminated through Cas9 cleavage, generating MGE-removed cells. We have successfully applied the Cas9-NE method to remove four representative MGEs, including plasmids, prophages, and genomic islands, from Vibrio strains. This new approach not only enables various investigations on MGEs but also has significant implications for the rapid generation of strains for commercial purposes.IMPORTANCEMobile genetic elements (MGEs) are of utmost importance for bacterial adaptation and pathogenicity, existing in various forms and multiple copies within bacterial cells. Integrated MGEs play dual roles in bacterial hosts, enhancing the fitness of the host by delivering cargo genes and potentially modifying the bacterial genome through the integration/excision process. This process can lead to alterations in promoters or coding sequences or even gene disruptions at integration sites, influencing the physiological functions of host bacteria. Here, we developed a new approach called Cas9-NE, allowing them to maintain the natural sequence changes associated with MGE excision. Cas9-NE allows the one-step removal of integrated and circular MGEs, addressing the challenge of eliminating various MGE forms efficiently. This approach simplifies MGE elimination in bacteria, expediting research on MGEs.
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Affiliation(s)
- Pengxia Wang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, China, Guangzhou
- Guangdong Provincial Observation and Research Station for Coastal Upwelling Ecosystem, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Shantou, China
- China, Southern Marine Science and Engineering Guangdong LaboratoryGuangzhou
- University of Chinese Academy of Sciences, Beijing, China
| | - Xiaofei Du
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, China, Guangzhou
- China, Southern Marine Science and Engineering Guangdong LaboratoryGuangzhou
- University of Chinese Academy of Sciences, Beijing, China
| | - Yi Zhao
- University of Chinese Academy of Sciences, Beijing, China
- College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei, China
| | - Weiquan Wang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, China, Guangzhou
- China, Southern Marine Science and Engineering Guangdong LaboratoryGuangzhou
- University of Chinese Academy of Sciences, Beijing, China
| | - Tongxuan Cai
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, China, Guangzhou
- College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei, China
| | - Kaihao Tang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, China, Guangzhou
- China, Southern Marine Science and Engineering Guangdong LaboratoryGuangzhou
- University of Chinese Academy of Sciences, Beijing, China
| | - Xiaoxue Wang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, China, Guangzhou
- China, Southern Marine Science and Engineering Guangdong LaboratoryGuangzhou
- University of Chinese Academy of Sciences, Beijing, China
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4
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MacDonald AI, Baksh A, Holland A, Shin H, Rice PA, Stark WM, Olorunniji FJ. Variable orthogonality of RDF - large serine integrase interactions within the ϕC31 family. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.03.587898. [PMID: 38617232 PMCID: PMC11014563 DOI: 10.1101/2024.04.03.587898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
Large serine integrases are phage- (or mobile element-) encoded enzymes that catalyse site-specific recombination reactions between a short DNA sequence on the phage genome (attP) and a corresponding host genome sequence (attB), thereby integrating the phage DNA into the host genome. Each integrase has its unique pair of attP and attB sites, a feature that allows them to be used as orthogonal tools for genome modification applications. In the presence of a second protein, the Recombination Directionality Factor (RDF), integrase catalyses the reverse, excisive reaction, generating new recombination sites, attR and attL. In addition to promoting attR x attL reaction, the RDF inhibits attP x attB recombination. This feature makes the directionality of integrase reactions programmable, allowing them to be useful for building synthetic biology devices. In this report, we describe the degree of orthogonality of both integrative and excisive reactions for three related integrases (ϕC31, ϕBT1, and TG1) and their RDFs. Among these, TG1 integrase is the most active, showing near complete recombination in both attP x attB and attR x attL reactions, and the most directional in the presence of its RDF. Our findings show that there is varying orthogonality among these three integrases - RDF pairs: ϕC31 integrase was the least selective, with all three RDFs activating it for attR x attL recombination. Similarly, ϕC31 RDF was the least effective among the three RDFs in promoting the excisive activities of the integrases, including its cognate ϕC31 integrase. ϕBT1 and TG1 RDFs were noticeably more effective than ϕC31 RDF at inhibiting attP x attB recombination by their respective integrases, making them more suitable for building reversible genetic switches. AlphaFold-Multimer predicts very similar structural interactions between each cognate integrase - RDF pair. The binding surface on RDF is much more conserved than the binding surface on integrase, an indication that specificity is determined more by the integrase than the RDF. Overall, the observed weak integrase/RDF orthogonality across the three enzymes emphasizes the need for identifying and characterizing more integrase - RDF pairs. Additionally, the ability of a particular integrase's preferred reaction direction to be controlled to varying degrees by non-cognate RDFs provides a path to tunable, non-binary genetic switches.
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Affiliation(s)
- Alasdair I. MacDonald
- School of Molecular Biosciences, University of Glasgow, Bower Building, Glasgow G12 8QQ, U.K
| | - Aron Baksh
- School of Pharmacy and Biomolecular Sciences, Faculty of Science, Liverpool John Moores University, James Parsons Building, Byrom Street, Liverpool L3 3AF, U.K
| | - Alex Holland
- School of Pharmacy and Biomolecular Sciences, Faculty of Science, Liverpool John Moores University, James Parsons Building, Byrom Street, Liverpool L3 3AF, U.K
| | - Heewhan Shin
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA
| | - Phoebe A. Rice
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA
| | - W. Marshall Stark
- School of Molecular Biosciences, University of Glasgow, Bower Building, Glasgow G12 8QQ, U.K
| | - Femi J. Olorunniji
- School of Pharmacy and Biomolecular Sciences, Faculty of Science, Liverpool John Moores University, James Parsons Building, Byrom Street, Liverpool L3 3AF, U.K
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5
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Kuhn J, Banerjee P, Haye A, Robinson DN, Iglesias PA, Devreotes PN. Complementary Cytoskeletal Feedback Loops Control Signal Transduction Excitability and Cell Polarity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.13.580131. [PMID: 38405988 PMCID: PMC10888828 DOI: 10.1101/2024.02.13.580131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
To move through complex environments, cells must constantly integrate chemical and mechanical cues. Signaling networks, such as those comprising Ras and PI3K, transmit chemical cues to the cytoskeleton, but the cytoskeleton must also relay mechanical information back to those signaling systems. Using novel synthetic tools to acutely control specific elements of the cytoskeleton in Dictyostelium and neutrophils, we delineate feedback mechanisms that alter the signaling network and promote front- or back-states of the cell membrane and cortex. First, increasing branched actin assembly increases Ras/PI3K activation while reducing polymeric actin levels overall decreases activation. Second, reducing myosin II assembly immediately increases Ras/PI3K activation and sensitivity to chemotactic stimuli. Third, inhibiting branched actin alone increases cortical actin assembly and strongly blocks Ras/PI3K activation. This effect is mitigated by reducing filamentous actin levels and in cells lacking myosin II. Finally, increasing actin crosslinking with a controllable activator of cytoskeletal regulator RacE leads to a large decrease in Ras activation both globally and locally. Curiously, RacE activation can trigger cell spreading and protrusion with no detectable activation of branched actin nucleators. Taken together with legacy data that Ras/PI3K promotes branched actin assembly and myosin II disassembly, our results define front- and back-promoting positive feedback loops. We propose that these loops play a crucial role in establishing cell polarity and mediating signal integration by controlling the excitable state of the signal transduction networks in respective regions of the membrane and cortex. This interplay enables cells to navigate intricate topologies like tissues containing other cells, the extracellular matrix, and fluids.
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Affiliation(s)
- Jonathan Kuhn
- Department of Cell Biology, Johns Hopkins School of Medicine, Baltimore, MD
| | - Parijat Banerjee
- Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD
| | - Andrew Haye
- Department of Cell Biology, Johns Hopkins School of Medicine, Baltimore, MD
| | | | - Pablo A. Iglesias
- Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD
| | - Peter N. Devreotes
- Department of Cell Biology, Johns Hopkins School of Medicine, Baltimore, MD
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6
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Roelle S, Kamath ND, Matreyek KA. Mammalian Genomic Manipulation with Orthogonal Bxb1 DNA Recombinase Sites for the Functional Characterization of Protein Variants. ACS Synth Biol 2023; 12:3352-3365. [PMID: 37922210 PMCID: PMC10661055 DOI: 10.1021/acssynbio.3c00355] [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: 06/10/2023] [Revised: 09/22/2023] [Accepted: 10/19/2023] [Indexed: 11/05/2023]
Abstract
The Bxb1 bacteriophage serine DNA recombinase is an efficient tool for engineering recombinant DNA into the genomes of cultured cells. Generally, a single engineered "landing pad" site is introduced into the cell genome, permitting the integration of transgenic circuits or libraries of transgene variants. While sufficient for many studies, the extent of genetic manipulation possible with a single recombinase site is limiting and insufficient for more complex cell-based assays. Here, we harnessed two orthogonal Bxb1 recombinase sites to enable alternative avenues for using mammalian synthetic biology to characterize transgenic protein variants. By designing plasmids flanked by a second pair of auxiliary recombination sites, we demonstrate that we can avoid the genomic integration of undesirable bacterial DNA elements using the same starting cells engineered for whole-plasmid integration. We also created "double landing pad" cells simultaneously harboring two orthogonal Bxb1 recombinase sites at separate genomic loci, allowing complex cell-based genetic assays. Integration of a genetically encoded calcium indicator allowed for the real-time monitoring of intracellular calcium signaling dynamics, including kinetic perturbations that occur upon overexpression of the wild-type or variant version of the calcium signaling relay protein STIM1. A panel of missense mutants of the HIV-1 accessory protein Vif was paired with various paralogs within the human Apobec3 innate immune protein family to identify combinations capable or incapable of interacting within cells. These cells allow transgenic protein variant libraries to be readily paired with assay-specific protein partners or biosensors, enabling new functional readouts for large-scale genetic assays for protein function.
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Affiliation(s)
- Sarah
M. Roelle
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, United States
| | - Nisha D. Kamath
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, United States
| | - Kenneth A. Matreyek
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, United States
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7
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Elmore JR, Dexter GN, Baldino H, Huenemann JD, Francis R, Peabody GL, Martinez-Baird J, Riley LA, Simmons T, Coleman-Derr D, Guss AM, Egbert RG. High-throughput genetic engineering of nonmodel and undomesticated bacteria via iterative site-specific genome integration. SCIENCE ADVANCES 2023; 9:eade1285. [PMID: 36897939 PMCID: PMC10005180 DOI: 10.1126/sciadv.ade1285] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 02/01/2023] [Indexed: 05/31/2023]
Abstract
Efficient genome engineering is critical to understand and use microbial functions. Despite recent development of tools such as CRISPR-Cas gene editing, efficient integration of exogenous DNA with well-characterized functions remains limited to model bacteria. Here, we describe serine recombinase-assisted genome engineering, or SAGE, an easy-to-use, highly efficient, and extensible technology that enables selection marker-free, site-specific genome integration of up to 10 DNA constructs, often with efficiency on par with or superior to replicating plasmids. SAGE uses no replicating plasmids and thus lacks the host range limitations of other genome engineering technologies. We demonstrate the value of SAGE by characterizing genome integration efficiency in five bacteria that span multiple taxonomy groups and biotechnology applications and by identifying more than 95 heterologous promoters in each host with consistent transcription across environmental and genetic contexts. We anticipate that SAGE will rapidly expand the number of industrial and environmental bacteria compatible with high-throughput genetics and synthetic biology.
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Affiliation(s)
- Joshua R. Elmore
- Biological Science Division, Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | - Gara N. Dexter
- Biosciences Division, Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Henri Baldino
- Biological Science Division, Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | - Jay D. Huenemann
- Biosciences Division, Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, TN 37831, USA
- Bredesen Center for Interdisciplinary Research, University of Tennessee, Knoxville, TN 37996,USA
| | - Ryan Francis
- Biological Science Division, Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | - George L. Peabody
- Biosciences Division, Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Jessica Martinez-Baird
- Biosciences Division, Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Lauren A. Riley
- Biosciences Division, Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, TN 37831, USA
- Bredesen Center for Interdisciplinary Research, University of Tennessee, Knoxville, TN 37996,USA
| | - Tuesday Simmons
- Plant and Microbial Biology Department, University of California, Berkeley, CA 94701, USA
| | - Devin Coleman-Derr
- Plant and Microbial Biology Department, University of California, Berkeley, CA 94701, USA
- Plant Gene Expression Center, USDA-ARS, Albany, CA 94710, USA
| | - Adam M. Guss
- Biosciences Division, Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Robert G. Egbert
- Biological Science Division, Pacific Northwest National Laboratory, Richland, WA 99354, USA
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8
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Pandey A, Rodriguez ML, Poole W, Murray RM. Characterization of Integrase and Excisionase Activity in a Cell-Free Protein Expression System Using a Modeling and Analysis Pipeline. ACS Synth Biol 2023; 12:511-523. [PMID: 36715625 DOI: 10.1021/acssynbio.2c00534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We present a full-stack modeling, analysis, and parameter identification pipeline to guide the modeling and design of biological systems starting from specifications to circuit implementations and parametrizations. We demonstrate this pipeline by characterizing the integrase and excisionase activity in a cell-free protein expression system. We build on existing Python tools─BioCRNpyler, AutoReduce, and Bioscrape─to create this pipeline. For enzyme-mediated DNA recombination in a cell-free system, we create detailed chemical reaction network models from simple high-level descriptions of the biological circuits and their context using BioCRNpyler. We use Bioscrape to show that the output of the detailed model is sensitive to many parameters. However, parameter identification is infeasible for this high-dimensional model; hence, we use AutoReduce to automatically obtain reduced models that have fewer parameters. This results in a hierarchy of reduced models under different assumptions to finally arrive at a minimal ODE model for each circuit. Then, we run sensitivity analysis-guided Bayesian inference using Bioscrape for each circuit to identify the model parameters. This process allows us to quantify integrase and excisionase activity in cell extracts enabling complex-circuit designs that depend on accurate control over protein expression levels through DNA recombination. The automated pipeline presented in this paper opens up a new approach to complex circuit design, modeling, reduction, and parametrization.
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Affiliation(s)
- Ayush Pandey
- Control and Dynamical Systems, California Institute of Technology, Pasadena, California91125, United States
| | - Makena L Rodriguez
- Biology and Biological Engineering, California Institute of Technology, Pasadena, California91125, United States
| | - William Poole
- Altos Laboratories, Redwood City, California94065, United States
| | - Richard M Murray
- Control and Dynamical Systems, California Institute of Technology, Pasadena, California91125, United States.,Biology and Biological Engineering, California Institute of Technology, Pasadena, California91125, United States
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9
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Efficient targeted transgenesis of large donor DNA into multiple mouse genetic backgrounds using bacteriophage Bxb1 integrase. Sci Rep 2022; 12:5424. [PMID: 35361849 PMCID: PMC8971409 DOI: 10.1038/s41598-022-09445-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 03/23/2022] [Indexed: 12/12/2022] Open
Abstract
The development of mouse models of human disease and synthetic biology research by targeted transgenesis of large DNA constructs represent a significant genetic engineering hurdle. We developed an efficient, precise, single-copy integration of large transgenes directly into zygotes using multiple mouse genetic backgrounds. We used in vivo Bxb1 mediated recombinase-mediated cassette exchange (RMCE) with a transgene “landing pad” composed of dual heterologous Bxb1 attachment (att) sites in cis, within the Gt(ROSA)26Sor safe harbor locus. RMCE of donor was achieved by microinjection of vector DNA carrying cognate attachment sites flanking the donor transgene with Bxb1-integrase mRNA. This approach achieves perfect vector-free integration of donor constructs at efficiencies > 40% with up to ~ 43 kb transgenes. Coupled with a nanopore-based Cas9-targeted sequencing (nCATS), complete verification of precise insertion sequence was achieved. As a proof-of-concept we describe the development of C57BL/6J and NSG Krt18-ACE2 models for SARS-CoV2 research with verified heterozygous N1 animals within ~ 4 months. Additionally, we created a series of mice with diverse backgrounds carrying a single att site including FVB/NJ, PWK/PhJ, NOD/ShiLtJ, CAST/EiJ and DBA/2J allowing for rapid transgene insertion. Combined, this system enables predictable, rapid development with simplified characterization of precisely targeted transgenic animals across multiple genetic backgrounds.
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10
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Hwang S, Lee Y, Kim JH, Kim G, Kim H, Kim W, Cho S, Palsson BO, Cho BK. Streptomyces as Microbial Chassis for Heterologous Protein Expression. Front Bioeng Biotechnol 2022; 9:804295. [PMID: 34993191 PMCID: PMC8724576 DOI: 10.3389/fbioe.2021.804295] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 11/30/2021] [Indexed: 12/29/2022] Open
Abstract
Heterologous production of recombinant proteins is gaining increasing interest in biotechnology with respect to productivity, scalability, and wide applicability. The members of genus Streptomyces have been proposed as remarkable hosts for heterologous production due to their versatile nature of expressing various secondary metabolite biosynthetic gene clusters and secretory enzymes. However, there are several issues that limit their use, including low yield, difficulty in genetic manipulation, and their complex cellular features. In this review, we summarize rational engineering approaches to optimizing the heterologous production of secondary metabolites and recombinant proteins in Streptomyces species in terms of genetic tool development and chassis construction. Further perspectives on the development of optimal Streptomyces chassis by the design-build-test-learn cycle in systems are suggested, which may increase the availability of secondary metabolites and recombinant proteins.
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Affiliation(s)
- Soonkyu Hwang
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Yongjae Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Ji Hun Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Gahyeon Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Hyeseong Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Woori Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Suhyung Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Bernhard O Palsson
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, United States.,Department of Pediatrics, University of California, San Diego, La Jolla, CA, United States.,Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Byung-Kwan Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,Innovative Biomaterials Research Center, KAIST Institutes, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
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11
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Ibarra-Chávez R, Hansen MF, Pinilla-Redondo R, Seed KD, Trivedi U. Phage satellites and their emerging applications in biotechnology. FEMS Microbiol Rev 2021; 45:fuab031. [PMID: 34104956 PMCID: PMC8632786 DOI: 10.1093/femsre/fuab031] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 06/07/2021] [Indexed: 12/11/2022] Open
Abstract
The arms race between (bacterio)phages and their hosts is a recognised hot spot for genome evolution. Indeed, phages and their components have historically paved the way for many molecular biology techniques and biotech applications. Further exploration into their complex lifestyles has revealed that phages are often parasitised by distinct types of hyperparasitic mobile genetic elements. These so-called phage satellites exploit phages to ensure their own propagation and horizontal transfer into new bacterial hosts, and their prevalence and peculiar lifestyle has caught the attention of many researchers. Here, we review the parasite-host dynamics of the known phage satellites, their genomic organisation and their hijacking mechanisms. Finally, we discuss how these elements can be repurposed for diverse biotech applications, kindling a new catalogue of exciting tools for microbiology and synthetic biology.
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Affiliation(s)
- Rodrigo Ibarra-Chávez
- Section of Microbiology, Department of Biology, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Mads Frederik Hansen
- Section of Microbiology, Department of Biology, University of Copenhagen, 2100 Copenhagen, Denmark
- Max Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany
| | - Rafael Pinilla-Redondo
- Section of Microbiology, Department of Biology, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Kimberley D Seed
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- Chan Zuckerberg Biohub, San Francisco, CA 94158, USA
| | - Urvish Trivedi
- Section of Microbiology, Department of Biology, University of Copenhagen, 2100 Copenhagen, Denmark
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12
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Chao G, Travis C, Church G. Measurement of large serine integrase enzymatic characteristics in HEK293 cells reveals variability and influence on downstream reporter expression. FEBS J 2021; 288:6410-6427. [PMID: 34043859 DOI: 10.1111/febs.16037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 04/20/2021] [Accepted: 05/25/2021] [Indexed: 11/30/2022]
Abstract
Large serine integrases (LSIs) offer tremendous potential for rapid genetic engineering as well as building biological systems capable of responding to stimuli and integrating information. Currently, there is no unified metric for directly measuring the enzymatic characteristics of LSI function, which hinders evaluation of their suitability to specific applications. Here, we present an experimental protocol for recording DNA recombination in HEK293 cells in real-time through fluorophore expression and software which fits the kinetic data to a model tailored to LSI recombination dynamics. Our model captures the activity of LSIs as three parameters: expression level (Kexp ), catalytic rate (kcat ), and substrate affinity (Kd ). The expression level and catalytic rate for phiC31 and Bxb1 varied greatly, suggesting disparate routes to high recombination efficiencies. Moreover, the expression level and substrate affinity jointly impacted downstream reporter expression, potentially by obstructing transcriptional machinery. We validated these observations by swapping between promoters and mutating key recombinase residues and DNA recognition sites to individually modulate each parameter. Our model for identifying key LSI parameters in cellulo provides insight into selecting the optimal recombinase for various applications as well as for guiding the engineering of improved LSIs.
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Affiliation(s)
- George Chao
- Genetics Department, Harvard Medical School, Boston, MA, USA
| | - Clair Travis
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - George Church
- Genetics Department, Harvard Medical School, Boston, MA, USA
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13
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Catone MV, Palomino MM, Legisa DM, Fina Martin J, Monedero García V, Ruzal SM, Allievi MC. Lactic acid production using cheese whey based medium in a stirred tank reactor by a ccpA mutant of Lacticaseibacillus casei. World J Microbiol Biotechnol 2021; 37:61. [PMID: 33719024 DOI: 10.1007/s11274-021-03028-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 03/02/2021] [Indexed: 11/24/2022]
Abstract
In lactobacilli, CcpA is known to modulate the expression of genes involved in sugar metabolism, stress response and aerobic adaptation. This study aimed to evaluate a ccpA mutant of Lacticaseibacillus casei BL23 to increase lactic acid production using cheese whey. The ccpA derivative (BL71) showed better growth than the L. casei wild-type in the whey medium. In a stirred tank reactor, at 48 h, lactate production by BL71 was eightfold higher than that by BL23. In batch fermentations, the final values reached were 44.23 g L-1 for BL71 and 27.58 g L-1 for BL23. Due to a decrease in the delay of lactate production in the mutant, lactate productivity increased from 0.17 g (L.h)-1 with BL23 to 0.80 g (L.h)-1 with BL71. We found that CcpA would play additional roles in nitrogen metabolism by the regulation of the proteolytic system. BL71 displayed higher activity of the PepX, PepQ and PrtP enzymes than BL23. Analysis of prtP expression confirmed this deregulation in BL71. Promoter analysis of the prtP gene revealed CcpA binding sites with high identity to the cre consensus sequence and the interaction of CcpA with this promoter was confirmed in vitro. We postulate that deregulation of the proteolytic system in BL71 allows a better exploitation of nitrogen resources in cheese whey, resulting in enhanced fermentation capacity. Therefore, the ccpA gene could be a good target for future technological developments aimed at effective and inexpensive lactate production from dairy industrial wastes.
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Affiliation(s)
- Mariela Verónica Catone
- Centro de Investigación y Desarrollo en Biotecnología Industrial, Instituto Nacional de Tecnología Industrial (INTI), Av. General Paz 5445, B1650AAC, San Martín, Buenos Aires, Argentina
| | - María Mercedes Palomino
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires - Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN) - CONICET, Ciudad Universitaria, C1428EGA, CABA, Argentina
| | - Danilo Mario Legisa
- Centro de Investigación y Desarrollo en Biotecnología Industrial, Instituto Nacional de Tecnología Industrial (INTI), Av. General Paz 5445, B1650AAC, San Martín, Buenos Aires, Argentina
| | - Joaquina Fina Martin
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires - Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN) - CONICET, Ciudad Universitaria, C1428EGA, CABA, Argentina
| | - Vicente Monedero García
- Instituto de Agroquímica y Tecnología de Alimentos-Consejo Superior de Investigaciones Científicas (IATA-CSIC), Av. Agustín Escardino 7, 46980, Paterna, Valencia, España
| | - Sandra Mónica Ruzal
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires - Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN) - CONICET, Ciudad Universitaria, C1428EGA, CABA, Argentina
| | - Mariana Claudia Allievi
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires - Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN) - CONICET, Ciudad Universitaria, C1428EGA, CABA, Argentina.
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14
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Askora A, Kawasaki T, Fujie M, Yamada T. In vitro characterization of the site-specific recombination system based on genus Habenivirus ϕRSM small serine integrase. Mol Genet Genomics 2021; 296:551-559. [PMID: 33575837 DOI: 10.1007/s00438-021-01762-5] [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: 10/30/2020] [Accepted: 01/27/2021] [Indexed: 10/22/2022]
Abstract
The genus Habenivirus which includes Ralstonia virus ϕRSM encodes a site-specific integrase of a small serine recombinase belonging to the resolvase/invertase family. Here we describe the integrative/excisive recombination reactions mediated by ϕRSM integrase using in vitro assays. The products of attP/attB recombination, i.e. attL and attR, were exactly identical to those found in the prophage ϕRSM in R. solanacearum strains. The minimum size of attB required for integration was determined to be 37 bp, containing a 13 bp core and flanking sequences of 4 bp on the left and 20 bp on the right. ϕRSM integrative recombination proceeds efficiently in vitro in the absence of additional proteins or high-energy cofactors. Excision of a functional phage genome from a prophage fragment was demonstrated in vitro, demonstrating two-way activity of ϕRSM1 integrase. This is the first example of a small serine recombinase from the resolvase/invertase group that functions in integrative and excisive recombination for filamentous phages. This serine integrase could be used as a tool for several genome engineering applications.
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Affiliation(s)
- Ahmed Askora
- Department of Botany and Microbiology, Faculty of Science, Zagazig University, Zagazig, 44519, Egypt.
| | - Takeru Kawasaki
- Unit of Biotechnology, Division of Biological and Life Sciences, Graduate School of Integrated Science for Life, Hiroshima University, Higashihiroshima, 739-8530, Japan
| | - Makoto Fujie
- Unit of Biotechnology, Division of Biological and Life Sciences, Graduate School of Integrated Science for Life, Hiroshima University, Higashihiroshima, 739-8530, Japan
| | - Takashi Yamada
- Unit of Biotechnology, Division of Biological and Life Sciences, Graduate School of Integrated Science for Life, Hiroshima University, Higashihiroshima, 739-8530, Japan. .,Hiroshima Study Center, The Open University of Japan, Naka-ku, Hiroshima, 730-0053, Japan.
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15
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Abe K, Takahashi T, Sato T. Extreme C-terminal element of SprA serine integrase is a potential component of the "molecular toggle switch" which controls the recombination and its directionality. Mol Microbiol 2020; 115:1110-1121. [PMID: 33244797 DOI: 10.1111/mmi.14654] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 10/26/2020] [Accepted: 11/21/2020] [Indexed: 12/11/2022]
Abstract
In Bacillus subtilis, a sporulation-related gene, spsM, is disrupted by SPβ prophage, but reconstituted during sporulation through SPβ excision. The spsM reconstitution is catalyzed by a site-specific DNA recombinase, SprA, and its cognate recombination directionality factor, SprB. SprB interacts with SprA, directing the SprA-mediated recombination reaction from integration to excision; however, the details of the directionality control remains unclear. Here, we demonstrate the importance of the extreme C-terminal region (ECT) of SprA in the DNA recombination and directionality control. We created a series of SprA C-terminal deletants and examined their DNA-binding and recombination activities. Deletions in the ECT caused a loss of integration and excision activity, the magnitudes of which positively correlated with the deletion size. Gel shift study revealed that the loss of the integration activity was attributable to the failure of synaptic complex formation. The excision deficiency was caused by defective interaction with SprB. Moreover, alanine scanning analysis revealed that Phe532 is essential to interact with SprB. SprAF532A , therefore, showed almost no excision activity, while retaining the integration activity. Collectively, these results suggest that the ECT plays the crucial roles in the interaction of SprA with SprB and possibly in the directional control of the recombination.
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Affiliation(s)
- Kimihiro Abe
- Research Center of Micro-Nano Technology, Hosei University, Koganei, Japan
| | - Takumi Takahashi
- Department of Frontier Bioscience, Hosei University, Koganei, Japan
| | - Tsutomu Sato
- Research Center of Micro-Nano Technology, Hosei University, Koganei, Japan.,Department of Frontier Bioscience, Hosei University, Koganei, Japan
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16
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Fan HF, Su BY, Ma CH, Rowley PA, Jayaram M. A bipartite thermodynamic-kinetic contribution by an activating mutation to RDF-independent excision by a phage serine integrase. Nucleic Acids Res 2020; 48:6413-6430. [PMID: 32479633 PMCID: PMC7337939 DOI: 10.1093/nar/gkaa401] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 05/02/2020] [Accepted: 05/08/2020] [Indexed: 12/11/2022] Open
Abstract
Streptomyces phage ϕC31 integrase (Int)—a large serine site-specific recombinase—is autonomous for phage integration (attP x attB recombination) but is dependent on the phage coded gp3, a recombination directionality factor (RDF), for prophage excision (attL x attR recombination). A previously described activating mutation, E449K, induces Int to perform attL x attR recombination in the absence of gp3, albeit with lower efficiency. E449K has no adverse effect on the competence of Int for attP x attB recombination. Int(E449K) resembles Int in gp3 mediated stimulation of attL x attR recombination and inhibition of attP x attB recombination. Using single-molecule analyses, we examined the mechanism by which E449K activates Int for gp3-independent attL x attR recombination. The contribution of E449K is both thermodynamic and kinetic. First, the mutation modulates the relative abundance of Int bound attL-attR site complexes, favoring pre-synaptic (PS) complexes over non-productively bound complexes. Roughly half of the synaptic complexes formed from Int(E449K) pre-synaptic complexes are recombination competent. By contrast, Int yields only inactive synapses. Second, E449K accelerates the dissociation of non-productively bound complexes and inactive synaptic complexes formed by Int. The extra opportunities afforded to Int(E499K) in reattempting synapse formation enhances the probability of success at fruitful synapsis.
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Affiliation(s)
- Hsiu-Fang Fan
- Institute of Medical Science and Technology, National Sun Yat-sen University, Sizihwan, Kaohsiung 804, Taiwan.,Department of Chemistry, National Sun Yat-sen University, Sizihwan, Kaohsiung 804, Taiwan.,Aerosol Science Research Center, National Sun Yat-sen University, Sizihwan, Kaohsiung 804, Taiwan
| | - Bo-Yu Su
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan
| | - Chien-Hui Ma
- Department of Molecular Biosciences, UT Austin, Austin, TX 78712, USA
| | - Paul A Rowley
- Department of Biological Sciences, University of Idaho, Moscow, ID 83844, USA
| | - Makkuni Jayaram
- Department of Molecular Biosciences, UT Austin, Austin, TX 78712, USA
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17
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Bernabé-Orts JM, Quijano-Rubio A, Vazquez-Vilar M, Mancheño-Bonillo J, Moles-Casas V, Selma S, Gianoglio S, Granell A, Orzaez D. A memory switch for plant synthetic biology based on the phage ϕC31 integration system. Nucleic Acids Res 2020; 48:3379-3394. [PMID: 32083668 PMCID: PMC7102980 DOI: 10.1093/nar/gkaa104] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 02/07/2020] [Accepted: 02/10/2020] [Indexed: 02/07/2023] Open
Abstract
Synthetic biology has advanced from the setup of basic genetic devices to the design of increasingly complex gene circuits to provide organisms with new functions. While many bacterial, fungal and mammalian unicellular chassis have been extensively engineered, this progress has been delayed in plants due to the lack of reliable DNA parts and devices that enable precise control over these new synthetic functions. In particular, memory switches based on DNA site-specific recombination have been the tool of choice to build long-term and stable synthetic memory in other organisms, because they enable a shift between two alternative states registering the information at the DNA level. Here we report a memory switch for whole plants based on the bacteriophage ϕC31 site-specific integrase. The switch was built as a modular device made of standard DNA parts, designed to control the transcriptional state (on or off) of two genes of interest by alternative inversion of a central DNA regulatory element. The state of the switch can be externally operated by action of the ϕC31 integrase (Int), and its recombination directionality factor (RDF). The kinetics, memory, and reversibility of the switch were extensively characterized in Nicotiana benthamiana plants.
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Affiliation(s)
- Joan Miquel Bernabé-Orts
- Instituto de Biología Molecular y Celular de Plantas (IBMCP). CSIC - Universidad Politécnica de Valencia. Camino de Vera s/n, 46022 Valencia, Spain
| | - Alfredo Quijano-Rubio
- Instituto de Biología Molecular y Celular de Plantas (IBMCP). CSIC - Universidad Politécnica de Valencia. Camino de Vera s/n, 46022 Valencia, Spain
| | - Marta Vazquez-Vilar
- Instituto de Biología Molecular y Celular de Plantas (IBMCP). CSIC - Universidad Politécnica de Valencia. Camino de Vera s/n, 46022 Valencia, Spain
| | - Javier Mancheño-Bonillo
- Instituto de Biología Molecular y Celular de Plantas (IBMCP). CSIC - Universidad Politécnica de Valencia. Camino de Vera s/n, 46022 Valencia, Spain
| | - Victor Moles-Casas
- Instituto de Biología Molecular y Celular de Plantas (IBMCP). CSIC - Universidad Politécnica de Valencia. Camino de Vera s/n, 46022 Valencia, Spain
| | - Sara Selma
- Instituto de Biología Molecular y Celular de Plantas (IBMCP). CSIC - Universidad Politécnica de Valencia. Camino de Vera s/n, 46022 Valencia, Spain
| | - Silvia Gianoglio
- Instituto de Biología Molecular y Celular de Plantas (IBMCP). CSIC - Universidad Politécnica de Valencia. Camino de Vera s/n, 46022 Valencia, Spain
| | - Antonio Granell
- Instituto de Biología Molecular y Celular de Plantas (IBMCP). CSIC - Universidad Politécnica de Valencia. Camino de Vera s/n, 46022 Valencia, Spain
| | - Diego Orzaez
- Instituto de Biología Molecular y Celular de Plantas (IBMCP). CSIC - Universidad Politécnica de Valencia. Camino de Vera s/n, 46022 Valencia, Spain
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18
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Compatibility of Site-Specific Recombination Units between Mobile Genetic Elements. iScience 2019; 23:100805. [PMID: 31926432 PMCID: PMC6957869 DOI: 10.1016/j.isci.2019.100805] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 12/06/2019] [Accepted: 12/19/2019] [Indexed: 12/17/2022] Open
Abstract
Site-specific recombination (SSR) systems are employed for transfer of mobile genetic elements (MGEs), such as lysogenic phages and integrative conjugative elements (ICEs). SSR between attP/I and attB sites is mediated by an integrase (Int) and a recombination directionality factor (RDF). The genome of Bacillus subtilis 168 contains SPβ, an active prophage, skin, a defective prophage, and ICEBs1, an integrative conjugative element. Each of these MGEs harbors the classic SSR unit attL-int-rdf-attR. Here, we demonstrate that these SSR units are all compatible and can substitute for one another. Specifically, when SPβ is turned into a defective prophage by deletion of its SSR unit, introduction of the SSR unit of skin or ICE converts it back to an active prophage. We also identified closely related prophages with distinct SSR units that control developmentally regulated gene rearrangements of kamA (L-lysine 2,3-aminomutase). These results suggest that SSR units are interchangeable components of MGEs. Lysogenic phage-derived SSR unit is sufficient to drive SSR of ICE and vice versa Defective prophage-derived SSR unit can drive the excision of the active lysogenic phage Closely related prophages with distinct SSR units control each gene rearrangements Correspondence between MGEs and their cognate SSR units is not absolute
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19
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Borgers K, Vandewalle K, Festjens N, Callewaert N. A guide to Mycobacterium mutagenesis. FEBS J 2019; 286:3757-3774. [PMID: 31419030 DOI: 10.1111/febs.15041] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 07/05/2019] [Accepted: 08/12/2019] [Indexed: 12/18/2022]
Abstract
The genus Mycobacterium includes several pathogens that cause severe disease in humans, like Mycobacterium tuberculosis (M. tb), the infectious agent causing tuberculosis. Genetic tools to engineer mycobacterial genomes, in a targeted or random fashion, have provided opportunities to investigate M. tb infection and pathogenesis. Furthermore, they have allowed the identification and validation of potential targets for the diagnosis, prevention, and treatment of tuberculosis. This review describes the various methods that are available for the generation of mutants in Mycobacterium species, focusing specifically on tools for altering slow-growing mycobacteria from the M. tb complex. Among others, it incorporates the recent new molecular biological technologies (e.g. ORBIT) to rapidly and/or genome-wide comprehensively obtain targeted mutants in mycobacteria. As such, this review can be used as a guide to select the appropriate genetic tools to generate mycobacterial mutants of interest, which can be used as tools to aid understanding of M. tb infection or to help developing TB intervention strategies.
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Affiliation(s)
- Katlyn Borgers
- VIB-UGhent Center for Medical Biotechnology, Belgium.,Department of Biochemistry and Microbiology, Ghent University, Belgium
| | - Kristof Vandewalle
- VIB-UGhent Center for Medical Biotechnology, Belgium.,Department of Biochemistry and Microbiology, Ghent University, Belgium
| | - Nele Festjens
- VIB-UGhent Center for Medical Biotechnology, Belgium.,Department of Biochemistry and Microbiology, Ghent University, Belgium
| | - Nico Callewaert
- VIB-UGhent Center for Medical Biotechnology, Belgium.,Department of Biochemistry and Microbiology, Ghent University, Belgium
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20
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Fogg PCM, Younger E, Fernando BD, Khaleel T, Stark WM, Smith MCM. Recombination directionality factor gp3 binds ϕC31 integrase via the zinc domain, potentially affecting the trajectory of the coiled-coil motif. Nucleic Acids Res 2019; 46:1308-1320. [PMID: 29228292 PMCID: PMC5814800 DOI: 10.1093/nar/gkx1233] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 11/29/2017] [Indexed: 11/24/2022] Open
Abstract
To establish a prophage state, the genomic DNA of temperate bacteriophages normally becomes integrated into the genome of their host bacterium by integrase-mediated, site-specific DNA recombination. Serine integrases catalyse a single crossover between an attachment site in the host (attB) and a phage attachment site (attP) on the circularized phage genome to generate the integrated prophage DNA flanked by recombinant attachment sites, attL and attR. Exiting the prophage state and entry into the lytic growth cycle requires an additional phage-encoded protein, the recombination directionality factor or RDF, to mediate recombination between attL and attR and excision of the phage genome. The RDF is known to bind integrase and switch its activity from integration (attP x attB) to excision (attL x attR) but its precise mechanism is unclear. Here, we identify amino acid residues in the RDF, gp3, encoded by the Streptomyces phage ϕC31 and within the ϕC31 integrase itself that affect the gp3:Int interaction. We show that residue substitutions in integrase that reduce gp3 binding adversely affect both excision and integration reactions. The mutant integrase phenotypes are consistent with a model in which the RDF binds to a hinge region at the base of the coiled-coil motif in ϕC31 integrase.
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Affiliation(s)
- Paul C M Fogg
- Department of Biology, University of York, Wentworth Way, York, YO10 5DD, UK
| | - Ellen Younger
- Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen AB25 2ZD, UK
| | - Booshini D Fernando
- Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen AB25 2ZD, UK
| | - Thanafez Khaleel
- Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen AB25 2ZD, UK
| | - W Marshall Stark
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow G12 8QQ, UK
| | - Margaret C M Smith
- Department of Biology, University of York, Wentworth Way, York, YO10 5DD, UK.,Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen AB25 2ZD, UK
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21
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Ramisetty BCM, Sudhakari PA. Bacterial 'Grounded' Prophages: Hotspots for Genetic Renovation and Innovation. Front Genet 2019; 10:65. [PMID: 30809245 PMCID: PMC6379469 DOI: 10.3389/fgene.2019.00065] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 01/24/2019] [Indexed: 01/07/2023] Open
Abstract
Bacterial genomes are highly plastic allowing the generation of variants through mutations and acquisition of genetic information. The fittest variants are then selected by the econiche thereby allowing the bacterial adaptation and colonization of the habitat. Larger genomes, however, may impose metabolic burden and hence bacterial genomes are optimized by the loss of frivolous genetic information. The activity of temperate bacteriophages has acute consequences on the bacterial population as well as the bacterial genome through lytic and lysogenic cycles. Lysogeny is a selective advantage as the prophage provides immunity to the lysogen against secondary phage attack. Since the non-lysogens are eliminated by the lytic phages, lysogens multiply and colonize the habitat. Nevertheless, all lysogens have an imminent risk of lytic cycle activation and cell lysis. However, a mutation in the attachment sites or in the genes that encode the specific recombinase responsible for prophage excision could result in 'grounding' of the prophage. Since the lysogens with grounded prophage are immune to respective phage infection as well as dodge the induction of lytic cycle, we hypothesize that the selection of these mutant lysogens is favored relative to their normal lysogenic counterparts. These grounded prophages offer several advantages to the bacterial genome evolution through propensity for genetic variations including inversions, deletions, and insertions via horizontal gene transfer. We propose that the grounded prophages expedite bacterial genome evolution by acting as 'genetic buffer zones' thereby increasing the frequency as well as the diversity of variations on which natural selection favors the beneficial variants. The grounded prophages are also hotspots for horizontal gene transfer wherein several ecologically significant genes such as those involved in stress tolerance, antimicrobial resistance, and novel metabolic pathways, are integrated. Moreover, the high frequency of genetic changes within prophages also allows proportionate probability for the de novo genesis of genetic information. Through sequence analyses of well-characterized E. coli prophages we exemplify various roles of grounded prophages in E. coli ecology and evolution. Therefore, the temperate prophages are one of the most significant drivers of bacterial genome evolution and sites of biogenesis of genetic information.
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Affiliation(s)
- Bhaskar Chandra Mohan Ramisetty
- Laboratory of Molecular Biology and Evolution, School of Chemical and Biotechnology, SASTRA Deemed University, Thanjavur, India
| | - Pavithra Anantharaman Sudhakari
- Laboratory of Molecular Biology and Evolution, School of Chemical and Biotechnology, SASTRA Deemed University, Thanjavur, India
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22
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Murphy KC, Nelson SJ, Nambi S, Papavinasasundaram K, Baer CE, Sassetti CM. ORBIT: a New Paradigm for Genetic Engineering of Mycobacterial Chromosomes. mBio 2018; 9:e01467-18. [PMID: 30538179 PMCID: PMC6299477 DOI: 10.1128/mbio.01467-18] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 10/19/2018] [Indexed: 11/20/2022] Open
Abstract
Two efficient recombination systems were combined to produce a versatile method for chromosomal engineering that obviates the need to prepare double-stranded DNA (dsDNA) recombination substrates. A synthetic "targeting oligonucleotide" is incorporated into the chromosome via homologous recombination mediated by the phage Che9c RecT annealase. This oligonucleotide contains a site-specific recombination site for the directional Bxb1 integrase (Int), which allows the simultaneous integration of a "payload plasmid" that contains a cognate recombination site and a selectable marker. The targeting oligonucleotide and payload plasmid are cotransformed into a RecT- and Int-expressing strain, and drug-resistant homologous recombinants are selected in a single step. A library of reusable target-independent payload plasmids is available to generate gene knockouts, promoter replacements, or C-terminal tags. This new system is called ORBIT (for "oligonucleotide-mediated recombineering followed by Bxb1 integrase targeting") and is ideally suited for the creation of libraries consisting of large numbers of deletions, insertions, or fusions in a bacterial chromosome. We demonstrate the utility of this "drag and drop" strategy by the construction of insertions or deletions in over 100 genes in Mycobacteriumtuberculosis and M. smegmatisIMPORTANCE We sought to develop a system that could increase the usefulness of oligonucleotide-mediated recombineering of bacterial chromosomes by expanding the types of modifications generated by an oligonucleotide (i.e., insertions and deletions) and by making recombinant formation a selectable event. This paper describes such a system for use in M. smegmatis and M. tuberculosis By incorporating a single-stranded DNA (ssDNA) version of the phage Bxb1 attP site into the oligonucleotide and coelectroporating it with a nonreplicative plasmid that carries an attB site and a drug selection marker, we show both formation of a chromosomal attP site and integration of the plasmid in a single transformation. No target-specific dsDNA substrates are required. This system will allow investigators studying mycobacterial diseases, including tuberculosis, to easily generate multiple mutants for analysis of virulence factors, identification of new drug targets, and development of new vaccines.
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Affiliation(s)
- Kenan C Murphy
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Samantha J Nelson
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Subhalaxmi Nambi
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Kadamba Papavinasasundaram
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Christina E Baer
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Christopher M Sassetti
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
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23
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Yan B, Pan Y, Jin Z, Liu X, Li W, Sun B. Interstrain transfer of the prophage ϕNM2 in staphylococcal strains. ANN MICROBIOL 2018. [DOI: 10.1007/s13213-018-1397-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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24
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Balabaskaran-Nina P, Desai SA. Diverse target gene modifications in Plasmodium falciparum using Bxb1 integrase and an intronic attB. Parasit Vectors 2018; 11:548. [PMID: 30333047 PMCID: PMC6192176 DOI: 10.1186/s13071-018-3129-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 10/01/2018] [Indexed: 12/26/2022] Open
Abstract
Genetic manipulation of the human malaria parasite Plasmodium falciparum is needed to explore pathogen biology and evaluate antimalarial targets. It is, however, aggravated by a low transfection efficiency, a paucity of selectable markers and a biased A/T-rich genome. While various enabling technologies have been introduced over the past two decades, facile and broad-range modification of essential genes remains challenging. We recently devised a new application of the Bxb1 integrase strategy to meet this need through an intronic attB sequence within the gene of interest. Although this attB is silent and without effect on intron splicing or protein translation and function, it allows efficient gene modification with minimal risk of unwanted changes at other genomic sites. We describe the range of applications for this new method as well as specific cases where it is preferred over CRISPR-Cas9 and other technologies. The advantages and limitations of various strategies for endogenous gene editing are also discussed.
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Affiliation(s)
- Praveen Balabaskaran-Nina
- The Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA.,Present Address: Department of Epidemiology and Public Health, Central University of Tamil Nadu, Thiruvarur, India
| | - Sanjay A Desai
- The Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA.
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25
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Li H, Sharp R, Rutherford K, Gupta K, Van Duyne GD. Serine Integrase attP Binding and Specificity. J Mol Biol 2018; 430:4401-4418. [PMID: 30227134 DOI: 10.1016/j.jmb.2018.09.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 09/07/2018] [Accepted: 09/11/2018] [Indexed: 01/31/2023]
Abstract
Serine integrases catalyze the site-specific insertion of viral DNA into a host's genome. The minimal requirements and irreversible nature of this integration reaction have led to the use of serine integrases in applications ranging from bacterial memory storage devices to gene therapy. Our understanding of how the integrase proteins recognize the viral (attP) and host (attB) attachment sites is limited, with structural data available for only a Listeria integrase C-terminal domain (CTD) bound to an attP half-site. Here we report quantitative binding and saturation mutagenesis analyses for the Listeria innocua prophage attP site and a new 2.8-Å crystal structure of the CTD•attP half site. We find that Int binds with high affinity to attP (6.9 nM), but the Int CTD binds to attP half-sites with only 7- to 10-fold lower affinity, supporting the idea that free energy is expended to open an Int dimer for attP binding. Despite the 50-bp Int-attP interaction surface, only 20 residues are sensitive to mutagenesis, and of these, only 6 require a specific residue for efficient Int binding and integration activity. One of the integrase DNA-binding domains, the recombinase domain, appears to be primarily non-specific. Several substitutions result in an improved attP site, indicating that higher-efficiency attachment sites can be obtained through site engineering. These findings advance our understanding of serine integrase function and provide important data for efforts towards engineering this family of enzymes for a variety of biotechnology applications.
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Affiliation(s)
- Huiguang Li
- Department of Biochemistry & Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Robert Sharp
- Department of Biochemistry & Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Karen Rutherford
- Department of Biochemistry & Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kushol Gupta
- Department of Biochemistry & Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Gregory D Van Duyne
- Department of Biochemistry & Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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26
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Anti-phage islands force their target phage to directly mediate island excision and spread. Nat Commun 2018; 9:2348. [PMID: 29904071 PMCID: PMC6002521 DOI: 10.1038/s41467-018-04786-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 05/11/2018] [Indexed: 02/07/2023] Open
Abstract
Vibrio cholerae, the causative agent of the diarrheal disease cholera, is antagonized by the lytic phage ICP1 in the aquatic environment and in human hosts. Mobile genetic elements called PLEs (phage-inducible chromosomal island-like elements) protect V. cholerae from ICP1 infection and initiate their anti-phage response by excising from the chromosome. Here, we show that PLE 1 encodes a large serine recombinase, Int, that exploits an ICP1-specific protein as a recombination directionality factor (RDF) to excise PLE 1 in response to phage infection. We show that this phage-encoded protein is sufficient to direct Int-mediated recombination in vitro and that it is highly conserved in all sequenced ICP1 genomes. Our results uncover an aspect of the molecular specificity underlying the conflict between a single predatory phage and V. cholerae PLE and contribute to our understanding of long-term evolution between phage and their bacterial hosts. Mobile genetic elements called PLEs protect Vibrio cholerae from infection with phage ICP1 by unclear mechanisms. Here, McKitterick and Seed show that a PLE-encoded large serine recombinase exploits an ICP1 protein as a recombination directionality factor to excise this PLE in response to phage infection.
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27
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CLAG3 Self-Associates in Malaria Parasites and Quantitatively Determines Nutrient Uptake Channels at the Host Membrane. mBio 2018; 9:mBio.02293-17. [PMID: 29739907 PMCID: PMC5941077 DOI: 10.1128/mbio.02293-17] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Malaria parasites increase host erythrocyte permeability to ions and nutrients via a broad-selectivity channel known as the plasmodial surface anion channel (PSAC), linked to parasite-encoded CLAG3 and two associated proteins. These proteins lack the multiple transmembrane domains typically present in channel-forming proteins, raising doubts about their precise roles. Using the virulent human Plasmodium falciparum parasite, we report that CLAG3 undergoes self-association and that this protein’s expression determines channel phenotype quantitatively. We overcame epigenetic silencing of clag3 paralogs and engineered parasites that express two CLAG3 isoforms simultaneously. Stoichiometric expression of these isoforms yielded intermediate channel phenotypes, in agreement with observed trafficking of both proteins to the host membrane. Coimmunoprecipitation and surface labeling revealed formation of CLAG3 oligomers. In vitro selections applied to these transfectant lines yielded distinct mutants with correlated changes in channel activity. These findings support involvement of the identified oligomers in PSAC formation and parasite nutrient acquisition. Malaria parasites are globally important pathogens that evade host immunity by replicating within circulating erythrocytes. To facilitate intracellular growth, these parasites increase erythrocyte nutrient uptake through an unusual ion channel. The parasite CLAG3 protein is a key determinant of this channel, but its lack of homology to known ion channels has raised questions about possible mechanisms. Using a new method that allows simultaneous expression of two different CLAG3 proteins, we identify self-association of CLAG3. The two expressed isoforms faithfully traffic to and insert in the host membrane, while remaining associated with two unrelated parasite proteins. Both the channel phenotypes and molecular changes produced upon selections with a highly specific channel inhibitor are consistent with a multiprotein complex that forms the nutrient pore. These studies support direct involvement of the CLAG3 protein in channel formation and are relevant to antimalarial drug discovery projects targeting parasite nutrient acquisition.
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28
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Lei X, Wang L, Zhao G, Ding X. Site-specificity of serine integrase demonstrated by the attB sequence preference of ɸBT1 integrase. FEBS Lett 2018. [PMID: 29512855 DOI: 10.1002/1873-3468.13023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Serine integrases mediate site-specific recombination and are extensively applied in genetic engineering and synthetic biology. However, which regions of the attachment sites determine site-specificity and how these regions function in recombination remain elusive. Here, we explored the sequence features of attB attachment sites recognized by ɸBT1 integrase, a representative serine integrase. A 34-bp DNA motif is found that displays distinct base-specific preference for every position. Further investigation of mutations at different positions within the attB sequence shows different recombination efficiencies and binding affinities. We found four conserved regions within the attB motif that coincide with the results of recombination assays, and mutations in the attB sequence that hamper recombination almost all cause reduced binding affinity.
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Affiliation(s)
- Xiaolai Lei
- Collaborative Innovation Center for Genetics and Development, State Key Laboratory of Genetic Engineering, Department of Microbiology, School of Life Sciences, Fudan University, Shanghai, China
| | - Lu Wang
- Collaborative Innovation Center for Genetics and Development, State Key Laboratory of Genetic Engineering, Department of Microbiology, School of Life Sciences, Fudan University, Shanghai, China
| | - Guoping Zhao
- Collaborative Innovation Center for Genetics and Development, State Key Laboratory of Genetic Engineering, Department of Microbiology, School of Life Sciences, Fudan University, Shanghai, China.,CAS Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.,Shanghai-MOST Key Laboratory of Disease and Health Genomics, Chinese National Human Genome Center at Shanghai, China
| | - Xiaoming Ding
- Collaborative Innovation Center for Genetics and Development, State Key Laboratory of Genetic Engineering, Department of Microbiology, School of Life Sciences, Fudan University, Shanghai, China
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29
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Abstract
Serine integrases catalyze precise rearrangement of DNA through site-specific recombination of small sequences of DNA called attachment (att) sites. Unlike other site-specific recombinases, the recombination reaction driven by serine integrases is highly directional and can only be reversed in the presence of an accessory protein called a recombination directionality factor (RDF). The ability to control reaction directionality has led to the development of serine integrases as tools for controlled rearrangement and modification of DNA in synthetic biology, gene therapy, and biotechnology. This review discusses recent advances in serine integrase technologies focusing on their applications in genome engineering, DNA assembly, and logic and data storage devices.
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Affiliation(s)
- Christine A. Merrick
- School
of Biological Sciences, University of Edinburgh, Roger Land Building, Alexander Crum
Brown Road, Edinburgh EH9
3FF, U.K
| | - Jia Zhao
- Novo
Nordisk (China) Pharmaceuticals Co., Ltd., Lei Shing Hong Center, Guangshunnan Avenue, Beijing 100102, China
| | - Susan J. Rosser
- School
of Biological Sciences, University of Edinburgh, Roger Land Building, Alexander Crum
Brown Road, Edinburgh EH9
3FF, U.K
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30
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Retraction: Site‐specific recombination of nitrogen‐fixation genes in cyanobacteria by XisF–XisH–XisI complex: Structures and models, William C. Hwang, James W. Golden, Jaime Pascual, Dong Xu, Anton Cheltsov, Adam Godzik. Proteins 2018; 86:268. [PMID: 30338965 PMCID: PMC5094899 DOI: 10.1002/prot.24679] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The above article from the Proteins: Structure, Function, and Bioinformatics, published online on 1 September 2014 in Wiley Online Library as Accepted Article (http://onlinelibrary.wiley.com/doi/10.1002/prot.24679/full), has been retracted by agreement between William C. Hwang, James W. Golden, Jaime Pascual, Dong Xu, Anton Cheltsov, Adam Godzik, the Editor‐in‐Chief, Bertrand E. Garcia‐Moreno, and Wiley Periodicals, Inc. The retraction has been agreed because submission was made without agreement from co‐author Adam Godzik.
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31
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Abe K, Takamatsu T, Sato T. Mechanism of bacterial gene rearrangement: SprA-catalyzed precise DNA recombination and its directionality control by SprB ensure the gene rearrangement and stable expression of spsM during sporulation in Bacillus subtilis. Nucleic Acids Res 2017; 45:6669-6683. [PMID: 28535266 PMCID: PMC5499854 DOI: 10.1093/nar/gkx466] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 05/12/2017] [Indexed: 12/17/2022] Open
Abstract
A sporulation-specific gene, spsM, is disrupted by an active prophage, SPβ, in the genome of Bacillus subtilis. SPβ excision is required for two critical steps: the onset of the phage lytic cycle and the reconstitution of the spsM-coding frame during sporulation. Our in vitro study demonstrated that SprA, a serine-type integrase, catalyzed integration and excision reactions between attP of SPβ and attB within spsM, while SprB, a recombination directionality factor, was necessary only for the excision between attL and attR in the SPβ lysogenic chromosome. DNA recombination occurred at the center of the short inverted repeat motif in the unique conserved 16 bp sequence among the att sites (5΄-ACAGATAA/AGCTGTAT-3΄; slash, breakpoint; underlines, inverted repeat), where SprA produced the 3΄-overhanging AA and TT dinucleotides for rejoining the DNA ends through base-pairing. Electrophoretic mobility shift assay showed that SprB promoted synapsis of SprA subunits bound to the two target sites during excision but impaired it during integration. In vivo data demonstrated that sprB expression that lasts until the late stage of sporulation is crucial for stable expression of reconstituted spsM without reintegration of the SPβ prophage. These results present a deeper understanding of the mechanism of the prophage-mediated bacterial gene regulatory system.
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Affiliation(s)
- Kimihiro Abe
- Research Center of Micro-Nano Technology, Hosei University, Koganei, Tokyo 184-0003, Japan
| | - Takuo Takamatsu
- Department of Frontier Bioscience, Hosei University, Koganei, Tokyo 184-8584, Japan
| | - Tsutomu Sato
- Research Center of Micro-Nano Technology, Hosei University, Koganei, Tokyo 184-0003, Japan.,Department of Frontier Bioscience, Hosei University, Koganei, Tokyo 184-8584, Japan
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32
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Olorunniji FJ, McPherson AL, Rosser SJ, Smith MCM, Colloms SD, Stark WM. Control of serine integrase recombination directionality by fusion with the directionality factor. Nucleic Acids Res 2017; 45:8635-8645. [PMID: 28666339 PMCID: PMC5737554 DOI: 10.1093/nar/gkx567] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 06/29/2017] [Indexed: 11/13/2022] Open
Abstract
Bacteriophage serine integrases are extensively used in biotechnology and synthetic biology for assembly and rearrangement of DNA sequences. Serine integrases promote recombination between two different DNA sites, attP and attB, to form recombinant attL and attR sites. The 'reverse' reaction requires another phage-encoded protein called the recombination directionality factor (RDF) in addition to integrase; RDF activates attL × attR recombination and inhibits attP × attB recombination. We show here that serine integrases can be fused to their cognate RDFs to create single proteins that catalyse efficient attL × attR recombination in vivo and in vitro, whereas attP × attB recombination efficiency is reduced. We provide evidence that activation of attL × attR recombination involves intra-subunit contacts between the integrase and RDF moieties of the fusion protein. Minor changes in the length and sequence of the integrase-RDF linker peptide did not affect fusion protein recombination activity. The efficiency and single-protein convenience of integrase-RDF fusion proteins make them potentially very advantageous for biotechnology/synthetic biology applications. Here, we demonstrate efficient gene cassette replacement in a synthetic metabolic pathway gene array as a proof of principle.
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Affiliation(s)
- Femi J Olorunniji
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Bower Building, Glasgow G12 8QQ, UK
| | - Arlene L McPherson
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Bower Building, Glasgow G12 8QQ, UK
| | - Susan J Rosser
- SynthSys - Synthetic and Systems Biology, School of Biological Sciences, University of Edinburgh, Roger Land Building, The King's Buildings, Mayfield Road, Edinburgh EH9 3JD, UK
| | - Margaret C M Smith
- Department of Biology, University of York, Wentworth Way, York YO10 5DD, UK
| | - Sean D Colloms
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Bower Building, Glasgow G12 8QQ, UK
| | - W Marshall Stark
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Bower Building, Glasgow G12 8QQ, UK
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33
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Gupta K, Sharp R, Yuan JB, Li H, Van Duyne GD. Coiled-coil interactions mediate serine integrase directionality. Nucleic Acids Res 2017; 45:7339-7353. [PMID: 28549184 PMCID: PMC5499577 DOI: 10.1093/nar/gkx474] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 05/15/2017] [Indexed: 11/14/2022] Open
Abstract
Serine integrases are bacteriophage enzymes that carry out site-specific integration and excision of their viral genomes. The integration reaction is highly directional; recombination between the phage attachment site attP and the host attachment site attB to form the hybrid sites attL and attR is essentially irreversible. In a recent model, extended coiled-coil (CC) domains in the integrase subunits are proposed to interact in a way that favors the attPxattB reaction but inhibits the attLxattR reaction. Here, we show for the Listeria innocua integrase (LI Int) system that the CC domain promotes self-interaction in isolated Int and when Int is bound to attachment sites. Three independent crystal structures of the CC domain reveal the molecular nature of the CC dimer interface. Alanine substitutions of key residues in the interface support the functional significance of the structural model and indicate that the same interaction is responsible for promoting integration and for inhibiting excision. An updated model of a LI Int•attL complex that incorporates the high resolution CC dimer structure provides insights that help to explain the unusual CC dimer structure and potential sources of stability in Int•attL and Int•attR complexes. Together, the data provide a molecular basis for understanding serine integrase directionality.
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MESH Headings
- Amino Acid Sequence
- Attachment Sites, Microbiological
- Bacteriophages/genetics
- Bacteriophages/metabolism
- Binding Sites
- Cloning, Molecular
- Crystallography, X-Ray
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- DNA, Bacterial/metabolism
- Escherichia coli/genetics
- Escherichia coli/metabolism
- Gene Expression
- Integrases/chemistry
- Integrases/genetics
- Integrases/metabolism
- Kinetics
- Listeria/genetics
- Listeria/metabolism
- Listeria/virology
- Models, Molecular
- Mutagenesis, Insertional
- Protein Binding
- Protein Conformation, alpha-Helical
- Protein Interaction Domains and Motifs
- Protein Multimerization
- Recombinant Proteins/chemistry
- Recombinant Proteins/genetics
- Recombinant Proteins/metabolism
- Recombination, Genetic
- Sequence Alignment
- Sequence Homology, Amino Acid
- Serine/chemistry
- Serine/metabolism
- Substrate Specificity
- Thermodynamics
- Viral Proteins/chemistry
- Viral Proteins/genetics
- Viral Proteins/metabolism
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Affiliation(s)
- Kushol Gupta
- Department of Biochemistry & Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 10104, USA
| | - Robert Sharp
- Department of Biochemistry & Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 10104, USA
| | - Jimmy B. Yuan
- Department of Biochemistry & Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 10104, USA
| | - Huiguang Li
- Department of Biochemistry & Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 10104, USA
| | - Gregory D. Van Duyne
- Department of Biochemistry & Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 10104, USA
- To whom correspondence should be addressed. Tel: +1 215 898 3058;
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Folliard T, Steel H, Prescott TP, Wadhams G, Rothschild LJ, Papachristodoulou A. A Synthetic Recombinase-Based Feedback Loop Results in Robust Expression. ACS Synth Biol 2017; 6:1663-1671. [PMID: 28602075 DOI: 10.1021/acssynbio.7b00131] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Accurate control of a biological process is essential for many critical functions in biology, from the cell cycle to proteome regulation. To achieve this, negative feedback is frequently employed to provide a highly robust and reliable output. Feedback is found throughout biology and technology, but due to challenges posed by its implementation, it is yet to be widely adopted in synthetic biology. In this paper we design a synthetic feedback network using a class of recombinase proteins called integrases, which can be re-engineered to flip the orientation of DNA segments in a digital manner. This system is highly orthogonal, and demonstrates a strong capability for regulating and reducing the expression variability of genes being transcribed under its control. An excisionase protein provides the negative feedback signal to close the loop in this system, by flipping DNA segments in the reverse direction. Our integrase/excisionase negative feedback system thus provides a modular architecture that can be tuned to suit applications throughout synthetic biology and biomanufacturing that require a highly robust and orthogonally controlled output.
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Affiliation(s)
- Thomas Folliard
- Department
of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, U.K
| | - Harrison Steel
- Department
of Engineering Science, University of Oxford, Parks Road, Oxford, OX1 3PJ, U.K
| | - Thomas P. Prescott
- Department
of Engineering Science, University of Oxford, Parks Road, Oxford, OX1 3PJ, U.K
| | - George Wadhams
- Department
of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, U.K
| | - Lynn J. Rothschild
- National
Aeronautics
and Space Administration Ames Research Center, Moffett Field, California 94035, United States
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Control of Recombination Directionality by the Listeria Phage A118 Protein Gp44 and the Coiled-Coil Motif of Its Serine Integrase. J Bacteriol 2017; 199:JB.00019-17. [PMID: 28289084 DOI: 10.1128/jb.00019-17] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 03/06/2017] [Indexed: 02/04/2023] Open
Abstract
The serine integrase of phage A118 catalyzes integrative recombination between attP on the phage and a specific attB locus on the chromosome of Listeria monocytogenes, but it is unable to promote excisive recombination between the hybrid attL and attR sites found on the integrated prophage without assistance by a recombination directionality factor (RDF). We have identified and characterized the phage-encoded RDF Gp44, which activates the A118 integrase for excision and inhibits integration. Gp44 binds to the C-terminal DNA binding domain of integrase, and we have localized the primary binding site to be within the mobile coiled-coil (CC) motif but distinct from the distal tip of the CC that is required for recombination. This interaction is sufficient to inhibit integration, but a second interaction involving the N-terminal end of Gp44 is also required to activate excision. We provide evidence that these two contacts modulate the trajectory of the CC motifs as they extend out from the integrase core in a manner dependent upon the identities of the four att sites. Our results support a model whereby Gp44 shapes the Int-bound complexes to control which att sites can synapse and recombine.IMPORTANCE Serine integrases mediate directional recombination between bacteriophage and bacterial chromosomes. These highly regulated site-specific recombination reactions are integral to the life cycle of temperate phage and, in the case of Listeria monocytogenes lysogenized by A118 family phage, are an essential virulence determinant. Serine integrases are also utilized as tools for genetic engineering and synthetic biology because of their exquisite unidirectional control of the DNA exchange reaction. Here, we identify and characterize the recombination directionality factor (RDF) that activates excision and inhibits integration reactions by the phage A118 integrase. We provide evidence that the A118 RDF binds to and modulates the trajectory of the long coiled-coil motif that extends from the large carboxyl-terminal DNA binding domain and is postulated to control the early steps of recombination site synapsis.
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36
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Genome Integration and Excision by a New Streptomyces Bacteriophage, ϕJoe. Appl Environ Microbiol 2017; 83:AEM.02767-16. [PMID: 28003200 PMCID: PMC5311408 DOI: 10.1128/aem.02767-16] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 12/18/2016] [Indexed: 01/27/2023] Open
Abstract
Bacteriophages are the source of many valuable tools for molecular biology and genetic manipulation. In Streptomyces, most DNA cloning vectors are based on serine integrase site-specific DNA recombination systems derived from phage. Because of their efficiency and simplicity, serine integrases are also used for diverse synthetic biology applications. Here, we present the genome of a new Streptomyces phage, ϕJoe, and investigate the conditions for integration and excision of the ϕJoe genome. ϕJoe belongs to the largest Streptomyces phage cluster (R4-like) and encodes a serine integrase. The attB site from Streptomyces venezuelae was used efficiently by an integrating plasmid, pCMF92, constructed using the ϕJoe int-attP locus. The attB site for ϕJoe integrase was occupied in several Streptomyces genomes, including that of S. coelicolor, by a mobile element that varies in gene content and size between host species. Serine integrases require a phage-encoded recombination directionality factor (RDF) to activate the excision reaction. The ϕJoe RDF was identified, and its function was confirmed in vivo. Both the integrase and RDF were active in in vitro recombination assays. The ϕJoe site-specific recombination system is likely to be an important addition to the synthetic biology and genome engineering toolbox. IMPORTANCEStreptomyces spp. are prolific producers of secondary metabolites, including many clinically useful antibiotics. Bacteriophage-derived integrases are important tools for genetic engineering, as they enable integration of heterologous DNA into the Streptomyces chromosome with ease and high efficiency. Recently, researchers have been applying phage integrases for a variety of applications in synthetic biology, including rapid assembly of novel combinations of genes, biosensors, and biocomputing. An important requirement for optimal experimental design and predictability when using integrases, however, is the need for multiple enzymes with different specificities for their integration sites. In order to provide a broad platform of integrases, we identified and validated the integrase from a newly isolated Streptomyces phage, ϕJoe. ϕJoe integrase is active in vitro and in vivo. The specific recognition site for integration is present in a wide range of different actinobacteria, including Streptomyces venezuelae, an emerging model bacterium in Streptomyces research.
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Olorunniji FJ, Merrick C, Rosser SJ, Smith MCM, Stark WM, Colloms SD. Multipart DNA Assembly Using Site-Specific Recombinases from the Large Serine Integrase Family. Methods Mol Biol 2017; 1642:303-323. [PMID: 28815508 DOI: 10.1007/978-1-4939-7169-5_19] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Assembling multiple DNA fragments into functional plasmids is an important and often rate-limiting step in engineering new functions in living systems. Bacteriophage integrases are enzymes that carry out efficient recombination reactions between short, defined DNA sequences known as att sites. These DNA splicing reactions can be used to assemble large numbers of DNA fragments into a functional circular plasmid in a method termed serine integrase recombinational assembly (SIRA). The resulting DNA assemblies can easily be modified by further recombination reactions catalyzed by the same integrase in the presence of its recombination directionality factor (RDF). Here we present a set of protocols for the overexpression and purification of bacteriophage ϕC31 and Bxb1 integrase and RDF proteins, their use in DNA assembly reactions, and subsequent modification of the resulting DNA assemblies.
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Affiliation(s)
- Femi J Olorunniji
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Bower Building, Glasgow, G12 8QQ, Scotland
| | - Christine Merrick
- SynthSys-Synthetic and Systems Biology, School of Biological Sciences, University of Edinburgh, CH Waddington Building, The King's Buildings, Mayfield Road, Edinburgh, EH9 3JD, Scotland
| | - Susan J Rosser
- SynthSys-Synthetic and Systems Biology, School of Biological Sciences, University of Edinburgh, CH Waddington Building, The King's Buildings, Mayfield Road, Edinburgh, EH9 3JD, Scotland
| | - Margaret C M Smith
- Department of Biology, University of York, Wentworth Way, York, YO10 5DD, UK
| | - W Marshall Stark
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Bower Building, Glasgow, G12 8QQ, Scotland
| | - Sean D Colloms
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Bower Building, Glasgow, G12 8QQ, Scotland.
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Pokhilko A, Zhao J, Stark WM, Colloms SD, Ebenhöh O. A simplified mathematical model of directional DNA site-specific recombination by serine integrases. J R Soc Interface 2017; 14:20160618. [PMID: 28077763 PMCID: PMC5310728 DOI: 10.1098/rsif.2016.0618] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 12/09/2016] [Indexed: 11/13/2022] Open
Abstract
Serine integrases catalyse site-specific recombination to integrate and excise bacteriophage genomes into and out of their host's genome. These enzymes exhibit remarkable directionality; in the presence of the integrase alone, recombination between attP and attB DNA sites is efficient and irreversible, giving attL and attR products which do not recombine further. However, in the presence of the bacteriophage-encoded recombination directionality factor (RDF), integrase efficiently promotes recombination between attL and attR to re-form attP and attB The DNA substrates and products of both reactions are approximately isoenergetic, and no cofactors (such as adenosine triphosphate) are required for recombination. The thermodynamic driving force for directionality of these reactions is thus enigmatic. Here, we present a minimal mathematical model which can explain the directionality and regulation of both 'forward' and 'reverse' reactions. In this model, the substrates of the 'forbidden' reactions (between attL and attR in the absence of RDF, attP and attB in the presence of RDF) are trapped as inactive protein-DNA complexes, ensuring that these 'forbidden' reactions are extremely slow. The model is in good agreement with the observed in vitro kinetics of recombination by ϕC31 integrase, and defines core features of the system necessary and sufficient for directionality.
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Affiliation(s)
- Alexandra Pokhilko
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow G12 8QQ, UK
| | - Jia Zhao
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow G12 8QQ, UK
| | - W Marshall Stark
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow G12 8QQ, UK
| | - Sean D Colloms
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow G12 8QQ, UK
| | - Oliver Ebenhöh
- Cluster of Excellence on Plant Sciences (CEPLAS), Heinrich-Heine-University, Universitätsstraße 1, 40225 Düsseldorf, Germany
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Wang X, Tang B, Ye Y, Mao Y, Lei X, Zhao G, Ding X. Bxb1 integrase serves as a highly efficient DNA recombinase in rapid metabolite pathway assembly. Acta Biochim Biophys Sin (Shanghai) 2017; 49:44-50. [PMID: 27864282 DOI: 10.1093/abbs/gmw115] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 10/24/2016] [Indexed: 11/13/2022] Open
Abstract
Phage-encoded serine integrases are widely used in genetic engineering. They also have the potential to serve as efficient DNA assemblers, demonstrated by the method of site-specific recombination-based tandem assembly (SSRTA) that can combine biological parts into devices, pathways, and systems. Here, four serine integrases, ϕBT1, TG1, ϕRv1, and Bxb1, were investigated to ascertain their in vitro DNA assembly activities. Bxb1 integrase displayed the highest efficiency to obtain final products. Thus, we conclude that Bxb1 integrase is an excellent choice for DNA assembly in vitro Using this enzyme and its recognition sites, BioBrick standards were designed that are compatible with the SSRTA method for module addition. A rapid and efficient procedure was developed for the assembly of a multigene metabolic pathway in one step, directly from non-cutting plasmids containing the gene fragments. This technique is easy and convenient, and would be of interest to the synthetic biology community.
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Affiliation(s)
- Xianwei Wang
- Collaborative Innovation Center for Genetics and Development, State Key Laboratory of Genetic Engineering, Department of Microbiology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Biao Tang
- Collaborative Innovation Center for Genetics and Development, State Key Laboratory of Genetic Engineering, Department of Microbiology, School of Life Sciences, Fudan University, Shanghai 200438, China
- CAS Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
- Institute of Quality and Standard for Agro-Products, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Yu Ye
- Department of Microbiology and Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China
| | - Yayi Mao
- Collaborative Innovation Center for Genetics and Development, State Key Laboratory of Genetic Engineering, Department of Microbiology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Xiaolai Lei
- Collaborative Innovation Center for Genetics and Development, State Key Laboratory of Genetic Engineering, Department of Microbiology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Guoping Zhao
- Collaborative Innovation Center for Genetics and Development, State Key Laboratory of Genetic Engineering, Department of Microbiology, School of Life Sciences, Fudan University, Shanghai 200438, China
- CAS Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
- Department of Microbiology and Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China
| | - Xiaoming Ding
- Collaborative Innovation Center for Genetics and Development, State Key Laboratory of Genetic Engineering, Department of Microbiology, School of Life Sciences, Fudan University, Shanghai 200438, China
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Fan HF, Hsieh TS, Ma CH, Jayaram M. Single-molecule analysis of ϕC31 integrase-mediated site-specific recombination by tethered particle motion. Nucleic Acids Res 2016; 44:10804-10823. [PMID: 27986956 PMCID: PMC5159548 DOI: 10.1093/nar/gkw861] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 09/11/2016] [Accepted: 09/22/2016] [Indexed: 11/14/2022] Open
Abstract
Serine and tyrosine site-specific recombinases (SRs and YRs, respectively) provide templates for understanding the chemical mechanisms and conformational dynamics of strand cleavage/exchange between DNA partners. Current evidence suggests a rather intriguing mechanism for serine recombination, in which one half of the cleaved synaptic complex undergoes a 180° rotation relative to the other. The 'small' and 'large' SRs contain a compact amino-terminal catalytic domain, but differ conspicuously in their carboxyl-terminal domains. So far, only one serine recombinase has been analyzed using single substrate molecules. We now utilized single-molecule tethered particle motion (TPM) to follow step-by-step recombination catalyzed by a large SR, phage ϕC31 integrase. The integrase promotes unidirectional DNA exchange between attB and attP sites to integrate the phage genome into the host chromosome. The recombination directionality factor (RDF; ϕC31 gp3) activates the excision reaction (attL × attR). From integrase-induced changes in TPM in the presence or absence of gp3, we delineated the individual steps of recombination and their kinetic features. The gp3 protein appears to regulate recombination directionality by selectively promoting or excluding active conformations of the synapse formed by specific att site partners. Our results support a 'gated rotation' of the synaptic complex between DNA cleavage and joining.
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Affiliation(s)
- Hsiu-Fang Fan
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, 112, Taiwan
- Biophotonics and Molecular Imaging Research Center, National Yang-Ming University, 112, Taiwan
| | - Tao-Shih Hsieh
- Institute of Cellular and Organismic Biology Academia Sinica, 115, Taiwan
| | - Chien-Hui Ma
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - Makkuni Jayaram
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
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Bowyer J, Zhao J, Subsoontorn P, Wong W, Rosser S, Bates D. Mechanistic Modeling of a Rewritable Recombinase Addressable Data Module. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2016; 10:1161-1170. [PMID: 27244749 DOI: 10.1109/tbcas.2016.2526668] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Many of the most important applications predicted to arise from Synthetic Biology will require engineered cellular memory with the capability to store data in a rewritable and reversible manner upon induction by transient stimuli. DNA recombination provides an ideal platform for cellular data storage and has allowed the development of a rewritable recombinase addressable data (RAD) module, capable of efficient data storage within a chromosome. Here, we develop the first detailed mechanistic model of DNA recombination, and validate it against a new set of in vitro data on recombination efficiencies across a range of different concentrations of integrase and gp3. Investigation of in vivo recombination dynamics using our model reveals the importance of fully accounting for all mechanistic features of DNA recombination in order to accurately predict the effect of different switching strategies on RAD module performance, and highlights its usefulness as a design tool for building future synthetic circuitry.
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Abstract
Inteins are self-splicing protein elements that are mobile at the DNA level and are sporadically distributed across microbial genomes. Inteins appear to be horizontally transferred, and it has been speculated that phages may play a role in intein distribution. Our attention turns to mycobacteriophages, which infect mycobacteria, where both phage and host harbor inteins. Using bioinformatics, mycobacteriophage genomes were mined for inteins. This study reveals that these mobile elements are present across multiple mycobacteriophage clusters and are pervasive in certain genes, like the large terminase subunit TerL and a RecB-like nuclease, with the majority of intein-containing genes being phage specific. Strikingly, despite this phage specificity, inteins localize to functional motifs shared with bacteria, such that intein-containing genes have similar roles, like hydrolase activity and nucleic acid binding, indicating a global commonality among intein-hosting proteins. Additionally, there are multiple insertion points within active centers, implying independent invasion events, with regulatory implications. Several phage inteins were shown to be splicing competent and to encode functional homing endonucleases, important for mobility. Further, bioinformatic analysis supports the potential for phages as facilitators of intein movement among mycobacteria and related genera. Analysis of catalytic intein residues finds the highly conserved penultimate histidine inconsistently maintained among mycobacteriophages. Biochemical characterization of a noncanonical phage intein shows that this residue influences precursor accumulation, suggesting that splicing has been tuned in phages to modulate generation of important proteins. Together, this work expands our understanding of phage-based intein dissemination and evolution and implies that phages provide a context for evolution of splicing-based regulation. Inteins are mobile protein splicing elements found in critical genes across all domains of life. Mycobacterial inteins are of particular interest because of their occurrence in pathogenic species, such as Mycobacterium tuberculosis and Mycobacterium leprae, which harbor inteins in important proteins. We have discovered a similarity in activities of intein-containing proteins among mycobacteriophages and their intein-rich actinobacterial hosts, with implications for both posttranslational regulation by inteins and phages participating in horizontal intein transfer. Our demonstration of multiple insertion points within active centers of phage proteins implies independent invasion events, indicating the importance of intein maintenance at specific functional sites. The variable conservation of a catalytic splicing residue, leading to profoundly altered splicing rates, points to the regulatory potential of inteins and to mycobacteriophages playing a role in intein evolution. Collectively, these results suggest inteins as posttranslational regulators and mycobacteriophages as both vehicles for intein distribution and incubators for intein evolution.
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43
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Keenholtz RA, Grindley NDF, Hatfull GF, Marko JF. Crossover-site sequence and DNA torsional stress control strand interchanges by the Bxb1 site-specific serine recombinase. Nucleic Acids Res 2016; 44:8921-8932. [PMID: 27550179 PMCID: PMC5062993 DOI: 10.1093/nar/gkw724] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 08/08/2016] [Indexed: 01/01/2023] Open
Abstract
DNA segment exchange by site-specific serine recombinases (SRs) is thought to proceed by rigid-body rotation of the two halves of the synaptic complex, following the cleavages that create the two pairs of exchangeable ends. It remains unresolved how the amount of rotation occurring between cleavage and religation is controlled. We report single-DNA experiments for Bxb1 integrase, a model SR, where dynamics of individual synapses were observed, using relaxation of supercoiling to report on cleavage and rotation events. Relaxation events often consist of multiple rotations, with the number of rotations per relaxation event and rotation velocity sensitive to DNA sequence at the center of the recombination crossover site, torsional stress and salt concentration. Bulk and single-DNA experiments indicate that the thermodynamic stability of the annealed, but cleaved, crossover sites controls ligation efficiency of recombinant and parental synaptic complexes, regulating the number of rotations during a breakage-religation cycle. The outcome is consistent with a ‘controlled rotation’ model analogous to that observed for type IB topoisomerases, with religation probability varying in accord with DNA base-pairing free energies at the crossover site. Significantly, we find no evidence for a special regulatory mechanism favoring ligation and product release after a single 180° rotation.
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Affiliation(s)
- Ross A Keenholtz
- Department of Molecular Biosciences, Northwestern University, Evanston, IL 60208, USA
| | - Nigel D F Grindley
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
| | - Graham F Hatfull
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - John F Marko
- Department of Molecular Biosciences, Northwestern University, Evanston, IL 60208, USA Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208, USA
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Pokhilko A, Zhao J, Ebenhöh O, Smith MCM, Stark WM, Colloms SD. The mechanism of ϕC31 integrase directionality: experimental analysis and computational modelling. Nucleic Acids Res 2016; 44:7360-72. [PMID: 27387286 PMCID: PMC5009753 DOI: 10.1093/nar/gkw616] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 06/28/2016] [Indexed: 02/04/2023] Open
Abstract
Serine integrases, DNA site-specific recombinases used by bacteriophages for integration and excision of their DNA to and from their host genomes, are increasingly being used as tools for programmed rearrangements of DNA molecules for biotechnology and synthetic biology. A useful feature of serine integrases is the simple regulation and unidirectionality of their reactions. Recombination between the phage attP and host attB sites is promoted by the serine integrase alone, giving recombinant attL and attR sites, whereas the ‘reverse’ reaction (between attL and attR) requires an additional protein, the recombination directionality factor (RDF). Here, we present new experimental data on the kinetics and regulation of recombination reactions mediated by ϕC31 integrase and its RDF, and use these data as the basis for a mathematical model of the reactions. The model accounts for the unidirectionality of the attP × attB and attL × attR reactions by hypothesizing the formation of structurally distinct, kinetically stable integrase–DNA product complexes, dependent on the presence or absence of RDF. The model accounts for all the available experimental data, and predicts how mutations of the proteins or alterations of reaction conditions might increase the conversion efficiency of recombination.
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Affiliation(s)
- Alexandra Pokhilko
- Institute of Molecular, Cell and Systems Biology, Bower Building, University of Glasgow, Glasgow G12 8QQ, Scotland, UK
| | - Jia Zhao
- Institute of Molecular, Cell and Systems Biology, Bower Building, University of Glasgow, Glasgow G12 8QQ, Scotland, UK
| | - Oliver Ebenhöh
- Cluster of Excellence on Plant Sciences (CEPLAS), Heinrich-Heine-University, Universitätsstraße 1, D-40225 Düsseldorf, Germany Institute for Complex Systems and Mathematical Biology, University of Aberdeen, AB24 3UE, UK
| | - Margaret C M Smith
- Department of Biology, University of York, Wentworth Way, York YO10 5DD, UK
| | - W Marshall Stark
- Institute of Molecular, Cell and Systems Biology, Bower Building, University of Glasgow, Glasgow G12 8QQ, Scotland, UK
| | - Sean D Colloms
- Institute of Molecular, Cell and Systems Biology, Bower Building, University of Glasgow, Glasgow G12 8QQ, Scotland, UK
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Lima-Junior JD, Viana-Niero C, Conde Oliveira DV, Machado GE, Rabello MCDS, Martins-Junior J, Martins LF, Digiampietri LA, da Silva AM, Setubal JC, Russell DA, Jacobs-Sera D, Pope WH, Hatfull GF, Leão SC. Characterization of mycobacteria and mycobacteriophages isolated from compost at the São Paulo Zoo Park Foundation in Brazil and creation of the new mycobacteriophage Cluster U. BMC Microbiol 2016; 16:111. [PMID: 27316672 PMCID: PMC4912749 DOI: 10.1186/s12866-016-0734-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 06/08/2016] [Indexed: 01/13/2023] Open
Abstract
Background A large collection of sequenced mycobacteriophages capable of infecting a single host strain of Mycobacterium smegmatis shows considerable genomic diversity with dozens of distinctive types (clusters) and extensive variation within those sharing evident nucleotide sequence similarity. Here we profiled the mycobacterial components of a large composting system at the São Paulo zoo. Results We isolated and sequenced eight mycobacteriophages using Mycobacterium smegmatis mc2155 as a host. None of these eight phages infected any of mycobacterial strains isolated from the same materials. The phage isolates span considerable genomic diversity, including two phages (Barriga, Nhonho) related to Subcluster A1 phages, two Cluster B phages (Pops, Subcluster B1; Godines, Subcluster B2), three Subcluster F1 phages (Florinda, Girafales, and Quico), and Madruga, a relative of phage Patience with which it constitutes the new Cluster U. Interestingly, the two Subcluster A1 phages and the three Subcluster F1 phages have genomic relationships indicating relatively recent evolution within a geographically isolated niche in the composting system. Conclusions We predict that composting systems such as those used to obtain these mycobacteriophages will be a rich source for the isolation of additional phages that will expand our view of bacteriophage diversity and evolution. Electronic supplementary material The online version of this article (doi:10.1186/s12866-016-0734-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- James Daltro Lima-Junior
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Cristina Viana-Niero
- Departmento de Ciências Biológicas, Universidade Federal de São Paulo, campus Diadema, São Paulo, Brazil
| | - Daniel V Conde Oliveira
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Gabriel Esquitini Machado
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | | | - Joaquim Martins-Junior
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Layla Farage Martins
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | | | - Aline Maria da Silva
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - João Carlos Setubal
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil.,Virginia Bioinformatics Institute, Blacksburg, VA, 24060, USA
| | - Daniel A Russell
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 1524, USA
| | - Deborah Jacobs-Sera
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 1524, USA
| | - Welkin H Pope
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 1524, USA
| | - Graham F Hatfull
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 1524, USA
| | - Sylvia Cardoso Leão
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil.
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Abstract
The large serine recombinases (LSRs) are a family of enzymes, encoded in temperate phage genomes or on mobile elements, that precisely cut and recombine DNA in a highly controllable and predictable way. In phage integration, the LSRs act at specific sites, the attP site in the phage and the attB site in the host chromosome, where cleavage and strand exchange leads to the integrated prophage flanked by the recombinant sites attL and attR. The prophage can excise by recombination between attL and attR but this requires a phage-encoded accessory protein, the recombination directionality factor (RDF). Although the LSRs can bind specifically to all the recombination sites, only specific integrase-bound sites can pair in a synaptic complex prior to strand exchange. Recent structural information has led to a breakthrough in our understanding of the mechanism of the LSRs, notably how the LSRs bind to their substrates and how LSRs display this site-selectivity. We also understand that the RDFs exercise control over the LSRs by protein-protein interactions. Other recent work with the LSRs have contributed to our understanding of how all serine recombinases undergo strand exchange subunit rotation, facilitated by surfaces that resemble a molecular bearing.
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Srivastava V, Thomson J. Gene stacking by recombinases. PLANT BIOTECHNOLOGY JOURNAL 2016; 14:471-82. [PMID: 26332944 DOI: 10.1111/pbi.12459] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 07/24/2015] [Accepted: 07/28/2015] [Indexed: 05/09/2023]
Abstract
Efficient methods of stacking genes into plant genomes are needed to expedite transfer of multigenic traits to crop varieties of diverse ecosystems. Over two decades of research has identified several DNA recombinases that carryout efficient cis and trans recombination between the recombination sites artificially introduced into the plant chromosome. The specificity and efficiency of recombinases make them extremely attractive for genome engineering. In plant biotechnology, recombinases have mostly been used for removing selectable marker genes and have rarely been extended to more complex applications. The reversibility of recombination, a property of the tyrosine family of recombinases, does not lend itself to gene stacking approaches that involve rounds of transformation for integrating genes into the engineered sites. However, recent developments in the field of recombinases have overcome these challenges and paved the way for gene stacking. Some of the key advancements include the application of unidirectional recombination systems, modification of recombination sites and transgene site modifications to allow repeated site-specific integrations into the selected site. Gene stacking is relevant to agriculturally important crops, many of which are difficult to transform; therefore, development of high-efficiency gene stacking systems will be important for its application on agronomically important crops, and their elite varieties. Recombinases, by virtue of their specificity and efficiency in plant cells, emerge as powerful tools for a variety of applications including gene stacking.
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Affiliation(s)
- Vibha Srivastava
- Department of Crop, Soil & Environmental Science, University of Arkansas, Fayetteville, AR, USA
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Bowyer J, Rosser S, Colloms S, Bates D. Development and experimental validation of a mechanistic model of in vitro DNA recombination. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2016; 2015:945-8. [PMID: 26736419 DOI: 10.1109/embc.2015.7318519] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Engineering cellular memory is a key area of research in which Synthetic Biology has already begun to make significant impacts. Recent work elucidating transcriptional memory devices has paved the way for the creation of bistable genetic switches based on DNA recombination. Attempts to experimentally design and build synthetic systems using recombinases have thus far been hindered by a lack of validated computational models that capture the mechanistic basis of DNA recombination. The predictive capabilities of such models could be exploited by Synthetic Biologists to reduce the number of iterative cycles required to align experimental results with design performance requirements. Here, we develop and validate the first detailed mechanistic model of DNA recombination, with a focus on how efficiently recombination can occur, and the model features required to replicate and predict experimental data.
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49
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Merrick C, Wardrope C, Paget J, Colloms S, Rosser S. Rapid Optimization of Engineered Metabolic Pathways with Serine Integrase Recombinational Assembly (SIRA). Methods Enzymol 2016; 575:285-317. [DOI: 10.1016/bs.mie.2016.02.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/06/2022]
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Fernandez-Rodriguez J, Yang L, Gorochowski TE, Gordon DB, Voigt CA. Memory and Combinatorial Logic Based on DNA Inversions: Dynamics and Evolutionary Stability. ACS Synth Biol 2015; 4:1361-72. [PMID: 26548807 DOI: 10.1021/acssynbio.5b00170] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Genetic memory can be implemented using enzymes that catalyze DNA inversions, where each orientation corresponds to a "bit". Here, we use two DNA invertases (FimE and HbiF) that reorient DNA irreversibly between two states with opposite directionality. First, we construct memory that is set by FimE and reset by HbiF. Next, we build a NOT gate where the input promoter drives FimE and in the absence of signal the reverse state is maintained by the constitutive expression of HbiF. The gate requires ∼3 h to turn on and off. The evolutionary stabilities of these circuits are measured by passaging cells while cycling function. The memory switch is stable over 400 h (17 days, 14 state changes); however, the gate breaks after 54 h (>2 days) due to continuous invertase expression. Genome sequencing reveals that the circuit remains intact, but the host strain evolves to reduce invertase expression. This work highlights the need to evaluate the evolutionary robustness and failure modes of circuit designs, especially as more complex multigate circuits are implemented.
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Affiliation(s)
- Jesus Fernandez-Rodriguez
- Synthetic
Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Lei Yang
- Synthetic
Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Thomas E. Gorochowski
- Synthetic
Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - D. Benjamin Gordon
- Synthetic
Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Broad
Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | - Christopher A. Voigt
- Synthetic
Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Broad
Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
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