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Varming AK, Huang Z, Hamad GM, Rasmussen KK, Ingmer H, Kilstrup M, Lo Leggio L. CI:Mor interactions in the lysogeny switches of Lactococcus lactis TP901-1 and Staphylococcus aureus φ13 bacteriophages. MICROBIOME RESEARCH REPORTS 2024; 3:15. [PMID: 38841409 PMCID: PMC11149083 DOI: 10.20517/mrr.2023.50] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 12/29/2023] [Accepted: 01/09/2024] [Indexed: 06/07/2024]
Abstract
Aim: To structurally characterize in detail the interactions between the phage repressor (CI) and the antirepressor (Mor) in the lysis-lysogeny switches of two Gram-positive bacteriophages, the lactococcal TP901-1 and staphylococcal φ13. Methods: We use crystallographic structure determination, computational structural modeling, and analysis, as well as biochemical methods, to elucidate similarities and differences in the CI:Mor interactions for the two genetic switches. Results: By comparing a newly determined and other available crystal structures for the N-terminal domain of CI (CI-NTD), we show that the CI interface involved in Mor binding undergoes structural changes upon binding in TP901-1. Most importantly, we show experimentally for the first time the direct interaction between CI and Mor for φ13, and model computationally the interaction interface. The computational modeling supports similar side chain rearrangements in TP901-1 and φ13. Conclusion: This study ascertains experimentally that, like in the TP901-1 lysogeny switch, staphylococcal φ13 CI and Mor interact with each other. The structural basis of the interaction of φ13 CI and Mor was computationally modeled and is similar to the interaction demonstrated experimentally between TP901-1 CI-NTD and Mor, likely involving similar rearrangement of residue side chains during the formation of the complex. The study identifies one CI residue, Glu69, which unusually interacts primarily through its aliphatic chain with an aromatic residue on Mor after changing its conformation compared to the un-complexed structure. This and other residues at the interface are suggested for investigation in future studies.
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Affiliation(s)
- Anders K. Varming
- Department of Chemistry, University of Copenhagen, Copenhagen DK-2100, Denmark
| | - Zhiyu Huang
- Department of Chemistry, University of Copenhagen, Copenhagen DK-2100, Denmark
| | - Ghofran M. Hamad
- Department of Chemistry, University of Copenhagen, Copenhagen DK-2100, Denmark
| | - Kim K. Rasmussen
- Department of Chemistry, University of Copenhagen, Copenhagen DK-2100, Denmark
| | - Hanne Ingmer
- Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg DK-1870, Denmark
| | - Mogens Kilstrup
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby DK-2800, Denmark
| | - Leila Lo Leggio
- Department of Chemistry, University of Copenhagen, Copenhagen DK-2100, Denmark
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2
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Erba EB, Pastore A. The Complementarity of Nuclear Magnetic Resonance and Native Mass Spectrometry in Probing Protein-Protein Interactions. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 3234:109-123. [PMID: 38507203 DOI: 10.1007/978-3-031-52193-5_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/22/2024]
Abstract
Nuclear magnetic resonance (NMR) and native mass spectrometry (MS) are mature physicochemical techniques with long histories and important applications. NMR spectroscopy provides detailed information about the structure, dynamics, interactions, and chemical environment of biomolecules. MS is an effective approach for determining the mass of biomolecules with high accuracy, sensitivity, and speed. The two techniques offer unique advantages and provide solid tools for structural biology. In the present review, we discuss their individual merits in the context of their applications to structural studies in biology with specific focus on protein interactions and evaluate their limitations. We provide specific examples in which these techniques can complement each other, providing new information on the same scientific case. We discuss how the field may develop and what challenges are expected in the future. Overall, the combination of NMR and MS plays an increasingly important role in integrative structural biology, assisting scientists in deciphering the three-dimensional structure of composite macromolecular assemblies.
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Pan L, Li D, Lin W, Liu W, Qin W, Xu L, Tong Y. Genomic analysis of a novel active prophage of Hafnia paralvei. Arch Virol 2022; 167:2027-2034. [PMID: 35752683 DOI: 10.1007/s00705-022-05498-4] [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: 11/14/2021] [Accepted: 04/20/2022] [Indexed: 11/30/2022]
Abstract
Little is known about the prophages in Hafniaceae bacteria. A novel Hafnia phage, yong2, was induced from Hafnia paralvei by treatment with mitomycin C. The phage has an elliptical head with dimensions of approximately 45 × 38 nm and a long noncontractile tail of approximately 157 × 4 nm. The complete genome of Hafnia phage yong2 is a 39,546-bp double-stranded DNA with a G+C content of 49.9%, containing 59 open reading frames (ORFs) and having at least one fixed terminus (GGGGCAGCGACA). In phylogenetic analysis, Hafnia phage yong2 clustered with four predicted Hafnia prophages and one predicted Enterobacteriaceae prophage. These prophages and members of the family Drexlerviridae together formed two distinct subclades nested within a clade, suggesting the existence of a novel class of prophages with conserved sequences and a unique evolutionary status not yet studied before in Hafniaceae and Enterobacteriaceae bacteria.
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Affiliation(s)
- Lingting Pan
- Key Laboratory of Marine Biotechnology, School of Marine Sciences, Ningbo University, Ningbo, 315211, Zhejiang, China
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Dengfeng Li
- Key Laboratory of Marine Biotechnology, School of Marine Sciences, Ningbo University, Ningbo, 315211, Zhejiang, China.
| | - Wei Lin
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Wencai Liu
- Key Laboratory of Marine Biotechnology, School of Marine Sciences, Ningbo University, Ningbo, 315211, Zhejiang, China
| | - Weinan Qin
- Key Laboratory of Marine Biotechnology, School of Marine Sciences, Ningbo University, Ningbo, 315211, Zhejiang, China
| | - Lihua Xu
- Key Laboratory of Marine Biotechnology, School of Marine Sciences, Ningbo University, Ningbo, 315211, Zhejiang, China
| | - Yigang Tong
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China.
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4
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Varming AK, Rasmussen KK, Zong Z, Thulstrup PW, Kilstrup M, Lo Leggio L. Flexible linker modulates the binding affinity of the TP901-1 CI phage repressor to DNA. FEBS J 2021; 289:1135-1148. [PMID: 34665941 DOI: 10.1111/febs.16238] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 09/16/2021] [Accepted: 10/18/2021] [Indexed: 11/30/2022]
Abstract
Temperate bacteriophages can switch between two life cycles following infection of a host bacterium: the lytic or lysogenic life cycle. The choice between these is controlled by a bistable genetic switch. We investigated the genetic switch of the lactococcal temperate bacteriophage, TP901-1, which is controlled by two regulatory proteins, the Clear 1 (CI) repressor and modulator of repression (MOR) antirepressor. CI consists of a DNA-binding N-terminal domain and a C-terminal domain responsible for oligomerization, connected by a flexible interdomain linker. Full-length CI is hexameric, whereas the truncated version CI with 58 C-terminal residues truncated (CIΔ58), missing the second C-terminal subdomain, is dimeric, but binds with the same affinity as full-length CI to the OL operator site, responsible for lytic genes transcription repression. Three variants of CIΔ58 with shorter, longer, and PP substituted linkers were produced and confirmed by circular dichroism spectroscopy and nanodifferential scanning fluorimetry to be well folded. With small-angle X-ray scattering, we delineated the conformational space sampled by the variants and wild-type in solution and found that shortening and lengthening the linker decrease and increase this, respectively, as also substantiated by molecular dynamics and as intended. Isoelectric focusing electrophoresis confirmed that all variants are able to bind to the MOR antirepressor. However, using electrophoretic mobility shift assays, we showed that shortening and lengthening the linker lead to a 94 and 17 times decrease in affinity to OL , respectively. Thus, an appropriate linker length appears to be crucial for appropriate DNA-binding and subsequent TP901-1 genetic switch function.
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Affiliation(s)
| | | | - Zhiyou Zong
- Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
| | | | - Mogens Kilstrup
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Leila Lo Leggio
- Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
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5
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Nuidate T, Kuaphiriyakul A, Surachat K, Mittraparp-arthorn P. Induction and Genome Analysis of HY01, a Newly Reported Prophage from an Emerging Shrimp Pathogen Vibrio campbellii. Microorganisms 2021; 9:400. [PMID: 33671959 PMCID: PMC7919010 DOI: 10.3390/microorganisms9020400] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 02/11/2021] [Accepted: 02/12/2021] [Indexed: 12/18/2022] Open
Abstract
Vibrio campbellii is an emerging aquaculture pathogen that causes luminous vibriosis in farmed shrimp. Although prophages in various aquaculture pathogens have been widely reported, there is still limited knowledge regarding prophages in the genome of pathogenic V. campbellii. Here, we describe the full-genome sequence of a prophage named HY01, induced from the emerging shrimp pathogen V. campbellii HY01. The phage HY01 was induced by mitomycin C and was morphologically characterized as long tailed phage. V. campbellii phage HY01 is composed of 41,772 bp of dsDNA with a G+C content of 47.45%. A total of 60 open reading frames (ORFs) were identified, of which 31 could be predicted for their biological functions. Twenty seven out of 31 predicted protein coding regions were matched with several encoded proteins of various Enterobacteriaceae, Pseudomonadaceae, Vibrionaceae, and other phages of Gram-negative bacteria. Interestingly, the comparative genome analysis revealed that the phage HY01 was only distantly related to Vibrio phage Va_PF430-3_p42 of fish pathogen V. anguillarum but differed in genomic size and gene organization. The phylogenetic tree placed the phage together with Siphoviridae family. Additionally, a survey of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) spacers revealed two matching sequences between phage HY01 genome and viral spacer sequence of Vibrio spp. The spacer results combined with the synteny results suggest that the evolution of V. campbellii phage HY01 is driven by the horizontal genetic exchange between bacterial families belonging to the class of Gammaproteobacteria.
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Affiliation(s)
- Taiyeebah Nuidate
- Division of Biological Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; (T.N.); (A.K.)
| | - Aphiwat Kuaphiriyakul
- Division of Biological Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; (T.N.); (A.K.)
| | - Komwit Surachat
- Division of Computational Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand;
- Molecular Evolution and Computational Biology Research Unit, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
| | - Pimonsri Mittraparp-arthorn
- Division of Biological Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; (T.N.); (A.K.)
- Molecular Evolution and Computational Biology Research Unit, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
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6
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Complete genome analysis of an active prophage of Vibrio alginolyticus. Arch Virol 2021; 166:891-896. [PMID: 33454862 DOI: 10.1007/s00705-020-04941-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 11/12/2020] [Indexed: 01/21/2023]
Abstract
An active prophage, Vibrio phage ValM-yong1, was isolated from pathogenic Vibrio alginolyticus by mitomycin C induction. This phage is a member of the family Myoviridae and contains a head approximately 90 nm in diameter and a retractable tail approximately 250 nm in length. The genome of the phage is 33,851 bp in length with a G+C content of 45.6%. The noteworthy features of Vibrio phage ValM-yong1 are its flower-like head and genomic mosaicism. Here, we focus on presenting the genomic characterization of the virus.
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7
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Revealing the mechanism of repressor inactivation during switching of a temperate bacteriophage. Proc Natl Acad Sci U S A 2020; 117:20576-20585. [PMID: 32788352 DOI: 10.1073/pnas.2005218117] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Temperate bacteriophages can enter one of two life cycles following infection of a sensitive host: the lysogenic or the lytic life cycle. The choice between the two alternative life cycles is dependent upon a tight regulation of promoters and their cognate regulatory proteins within the phage genome. We investigated the genetic switch of TP901-1, a bacteriophage of Lactococcus lactis, controlled by the CI repressor and the modulator of repression (MOR) antirepressor and their interactions with DNA. We determined the solution structure of MOR, and we solved the crystal structure of MOR in complex with the N-terminal domain of CI, revealing the structural basis of MOR inhibition of CI binding to the DNA operator sites. 15N NMR Carr-Purcell-Meiboom-Gill (CPMG) relaxation dispersion and rotating frame R 1ρ measurements demonstrate that MOR displays molecular recognition dynamics on two different time scales involving a repacking of aromatic residues at the interface with CI. Mutations in the CI:MOR binding interface impair complex formation in vitro, and when introduced in vivo, the bacteriophage switch is unable to choose the lytic life cycle showing that the CI:MOR complex is essential for proper functioning of the genetic switch. On the basis of sequence alignments, we show that the structural features of the MOR:CI complex are likely conserved among a larger family of bacteriophages from human pathogens implicated in transfer of antibiotic resistance.
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de Groot A, Siponen MI, Magerand R, Eugénie N, Martin-Arevalillo R, Doloy J, Lemaire D, Brandelet G, Parcy F, Dumas R, Roche P, Servant P, Confalonieri F, Arnoux P, Pignol D, Blanchard L. Crystal structure of the transcriptional repressor DdrO: insight into the metalloprotease/repressor-controlled radiation response in Deinococcus. Nucleic Acids Res 2020; 47:11403-11417. [PMID: 31598697 PMCID: PMC6868357 DOI: 10.1093/nar/gkz883] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Revised: 09/25/2019] [Accepted: 10/01/2019] [Indexed: 12/13/2022] Open
Abstract
Exposure to harmful conditions such as radiation and desiccation induce oxidative stress and DNA damage. In radiation-resistant Deinococcus bacteria, the radiation/desiccation response is controlled by two proteins: the XRE family transcriptional repressor DdrO and the COG2856 metalloprotease IrrE. The latter cleaves and inactivates DdrO. Here, we report the biochemical characterization and crystal structure of DdrO, which is the first structure of a XRE protein targeted by a COG2856 protein. DdrO is composed of two domains that fold independently and are separated by a flexible linker. The N-terminal domain corresponds to the DNA-binding domain. The C-terminal domain, containing three alpha helices arranged in a novel fold, is required for DdrO dimerization. Cleavage by IrrE occurs in the loop between the last two helices of DdrO and abolishes dimerization and DNA binding. The cleavage site is hidden in the DdrO dimer structure, indicating that IrrE cleaves DdrO monomers or that the interaction with IrrE induces a structural change rendering accessible the cleavage site. Predicted COG2856/XRE regulatory protein pairs are found in many bacteria, and available data suggest two different molecular mechanisms for stress-induced gene expression: COG2856 protein-mediated cleavage or inhibition of oligomerization without cleavage of the XRE repressor.
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Affiliation(s)
- Arjan de Groot
- Aix Marseille Univ, CEA, CNRS, BIAM, Molecular and Environmental Microbiology Team, Saint Paul-Lez-Durance, F-13108, France
| | - Marina I Siponen
- Aix Marseille Univ, CEA, CNRS, BIAM, Molecular and Environmental Microbiology Team, Saint Paul-Lez-Durance, F-13108, France
| | - Romaric Magerand
- Aix Marseille Univ, CEA, CNRS, BIAM, Molecular and Environmental Microbiology Team, Saint Paul-Lez-Durance, F-13108, France
| | - Nicolas Eugénie
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Univ. Paris-Saclay, Gif-sur-Yvette cedex, F-91198, France
| | | | - Jade Doloy
- Aix Marseille Univ, CEA, CNRS, BIAM, Molecular and Environmental Microbiology Team, Saint Paul-Lez-Durance, F-13108, France
| | - David Lemaire
- Aix Marseille Univ, CEA, CNRS, BIAM, Interaction Protein Metal Team, Saint Paul-Lez-Durance, F-13108, France
| | - Géraldine Brandelet
- Aix Marseille Univ, CEA, CNRS, BIAM, Molecular and Environmental Microbiology Team, Saint Paul-Lez-Durance, F-13108, France
| | - François Parcy
- Univ. Grenoble Alpes, CNRS, CEA, INRA, IRIG-DBSCI-LPCV, Grenoble, F-38000, France
| | - Renaud Dumas
- Univ. Grenoble Alpes, CNRS, CEA, INRA, IRIG-DBSCI-LPCV, Grenoble, F-38000, France
| | - Philippe Roche
- Aix Marseille Univ, CNRS, Inserm, Institut Paoli Calmettes, CRCM, Marseille CEDEX 09, F-13273, France
| | - Pascale Servant
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Univ. Paris-Saclay, Gif-sur-Yvette cedex, F-91198, France
| | - Fabrice Confalonieri
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Univ. Paris-Saclay, Gif-sur-Yvette cedex, F-91198, France
| | - Pascal Arnoux
- Aix Marseille Univ, CEA, CNRS, BIAM, Molecular and Environmental Microbiology Team, Saint Paul-Lez-Durance, F-13108, France
| | - David Pignol
- Aix Marseille Univ, CEA, CNRS, BIAM, Molecular and Environmental Microbiology Team, Saint Paul-Lez-Durance, F-13108, France
| | - Laurence Blanchard
- Aix Marseille Univ, CEA, CNRS, BIAM, Molecular and Environmental Microbiology Team, Saint Paul-Lez-Durance, F-13108, France
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9
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Pedersen M, Neergaard JT, Cassias J, Rasmussen KK, Lo Leggio L, Sneppen K, Hammer K, Kilstrup M. Repression of the lysogenic P R promoter in bacteriophage TP901-1 through binding of a CI-MOR complex to a composite O M-O R operator. Sci Rep 2020; 10:8659. [PMID: 32457340 PMCID: PMC7250872 DOI: 10.1038/s41598-020-65493-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 05/04/2020] [Indexed: 11/09/2022] Open
Abstract
A functional genetic switch from the lactococcal bacteriophage TP901-1, deciding which of two divergently transcribing promoters becomes most active and allows this bi-stable decision to be inherited in future generations requires a DNA region of less than 1 kb. The fragment encodes two repressors, CI and MOR, transcribed from the PR and PL promoters respectively. CI can repress the transcription of the mor gene at three operator sites (OR, OL, and OD), leading to the immune state. Repression of the cI gene, leading to the lytic (anti-immune) state, requires interaction between CI and MOR by an unknown mechanism, but involving a CI:MOR complex. A consensus for putative MOR binding sites (OM sites), and a common topology of three OM sites adjacent to the OR motif was here identified in diverse phage switches that encode CI and MOR homologs, in a search for DNA sequences similar to the TP901-1 switch. The OR site and all putative OM sites are important for establishment of the anti-immune repression of PR, and a putative DNA binding motif in MOR is needed for establishment of the anti-immune state. Direct evidence for binding between CI and MOR is here shown by pull-down experiments, chemical crosslinking, and size exclusion chromatography. The results are consistent with two possible models for establishment of the anti-immune repression of cI expression at the PR promoter.
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Affiliation(s)
- Margit Pedersen
- University of Copenhagen, Department of Biology, Copenhagen, DK2200, Denmark
| | - Jesper Tvenge Neergaard
- Technical University of Denmark, Department of Biotechnology and Biomedicine, Lyngby, DK2800, Denmark
| | - Johan Cassias
- Technical University of Denmark, Department of Biotechnology and Biomedicine, Lyngby, DK2800, Denmark
| | | | - Leila Lo Leggio
- University of Copenhagen, Department of Chemistry, Copenhagen, DK2200, Denmark
| | - Kim Sneppen
- University of Copenhagen, Center for Models of Life, Copenhagen, DK2200, Denmark
| | - Karin Hammer
- Technical University of Denmark, Department of Biotechnology and Biomedicine, Lyngby, DK2800, Denmark
| | - Mogens Kilstrup
- Technical University of Denmark, Department of Biotechnology and Biomedicine, Lyngby, DK2800, Denmark.
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Sarkar K, Mukhopadhyay S, Bonnerjee D, Srivastava R, Bagh S. A frame-shifted gene, which rescued its function by non-natural start codons and its application in constructing synthetic gene circuits. J Biol Eng 2019; 13:20. [PMID: 30867677 PMCID: PMC6397469 DOI: 10.1186/s13036-019-0151-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 02/20/2019] [Indexed: 12/22/2022] Open
Abstract
Background Frame-shifted genes results in non-functional peptides. Because of this complete loss of function, frame-shifted genes have never been used in constructing synthetic gene circuits. Results Here we report that the function of gene circuits is rescued by a frame-shifted gene, which functions by translating from a non-natural start codon. We report a single nucleotide deletion mutation that developed in the λ-repressor cI within a synthetic genetic NOT gate in Escherichia coli during growth and through this mutation, a non-functional synthetic gene circuit became functional. This mutation resulted in a frame-shifted cI, which showed effective functionality among genetic NOT-gates in Escherichia coli with high regulatory ranges (> 300) and Hill coefficient (> 6.5). The cI worked over a large range of relative copy numbers between the frame-shifted gene and its target promoter. These properties make this frame-shifted gene an excellent candidate for building synthetic gene circuits. We hypothesized a new operating mechanism and showed evidence that frame-shifted cI was translated from non-natural start codon. We have engineered and tested a series of NOT gates made from a library of cI genes, each of which starts from a different codon within the first several amino acids of the frame-shifted cI. It is found that one form with start codon ACA, starting from the 3rd codon had similar repression behavior as the whole frame-shifted gene. We demonstrated synthetic genetic NAND and NOR logic-gates with frame-shifted cI. This is the first report of synthetic-gene-circuits made from a frame-shifted gene. Conclusions This study inspires a new view on frame-shifted gene and may serve as a novel way of building and optimizing synthetic-gene-circuits. This work may also have significance in the understanding of non-directed evolution of synthetic genetic circuits. Electronic supplementary material The online version of this article (10.1186/s13036-019-0151-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Kathakali Sarkar
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Homi Bhabha National Institute, Block A/F, Sector-I, Bidhannagar, Kolkata, 700064 India
| | - Sayak Mukhopadhyay
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Homi Bhabha National Institute, Block A/F, Sector-I, Bidhannagar, Kolkata, 700064 India
| | - Deepro Bonnerjee
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Homi Bhabha National Institute, Block A/F, Sector-I, Bidhannagar, Kolkata, 700064 India
| | - Rajkamal Srivastava
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Homi Bhabha National Institute, Block A/F, Sector-I, Bidhannagar, Kolkata, 700064 India
| | - Sangram Bagh
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Homi Bhabha National Institute, Block A/F, Sector-I, Bidhannagar, Kolkata, 700064 India
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11
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Multiple Mechanisms Are Involved in Repression of Filamentous Phage SW1 Transcription by the DNA-Binding Protein FpsR. J Mol Biol 2019; 431:1113-1126. [DOI: 10.1016/j.jmb.2019.01.040] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 01/16/2019] [Accepted: 01/31/2019] [Indexed: 01/21/2023]
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12
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Rasmussen KK, Varming AK, Schmidt SN, Frandsen KEH, Thulstrup PW, Jensen MR, Lo Leggio L. Structural basis of the bacteriophage TP901-1 CI repressor dimerization and interaction with DNA. FEBS Lett 2018; 592:1738-1750. [PMID: 29683476 DOI: 10.1002/1873-3468.13060] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 04/12/2018] [Accepted: 04/12/2018] [Indexed: 12/31/2022]
Abstract
Temperate bacteriophages are known for their bistability, which in TP901-1 is controlled by two proteins, CI and MOR. Clear 1 repressor (CI) is hexameric and binds three palindromic operator sites via an N-terminal helix-turn-helix domain (NTD). A dimeric form, such as the truncated CI∆58 investigated here, is necessary for high-affinity binding to DNA. The crystal structure of the dimerization region (CTD1 ) is determined here, showing that it forms a pair of helical hooks. This newly determined structure is used together with the known crystal structure of the CI-NTD and small angle X-ray scattering data, to determine the solution structure of CI∆58 in complex with a palindromic operator site, showing that the two NTDs bind on opposing sides of the DNA helix.
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13
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Allison JR. Using simulation to interpret experimental data in terms of protein conformational ensembles. Curr Opin Struct Biol 2017; 43:79-87. [DOI: 10.1016/j.sbi.2016.11.018] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 11/15/2016] [Accepted: 11/21/2016] [Indexed: 01/03/2023]
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