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Xu Q, Tang L, Liu W, Xu N, Hu Y, Zhang Y, Chen S. Phage protein Gp11 blocks Staphylococcus aureus cell division by inhibiting peptidoglycan biosynthesis. mBio 2024; 15:e0067924. [PMID: 38752726 DOI: 10.1128/mbio.00679-24] [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: 03/08/2024] [Accepted: 04/10/2024] [Indexed: 06/13/2024] Open
Abstract
Phages and bacteria have a long history of co-evolution. However, these dynamics of phage-host interactions are still largely unknown; identification of phage inhibitors that remodel host metabolism will provide valuable information for target development for antimicrobials. Here, we perform a comprehensive screen for early-gene products of ΦNM1 that inhibit cell growth in Staphylococcus aureus. A small membrane protein, Gp11, with inhibitory effects on S. aureus cell division was identified. A bacterial two-hybrid library containing 345 essential S. aureus genes was constructed to screen for targets of Gp11, and Gp11 was found to interact with MurG and DivIC. Defects in cell growth and division caused by Gp11 were dependent on MurG and DivIC, which was further confirmed using CRISPRi hypersensitivity assay. Gp11 interacts with MurG, the protein essential for cell wall formation, by inhibiting the production of lipid II to regulate peptidoglycan (PG) biosynthesis on the cell membrane. Gp11 also interacts with cell division protein DivIC, an essential part of the division machinery necessary for septal cell wall assembly, to disrupt the recruitment of division protein FtsW. Mutations in Gp11 result in loss of its ability to cause growth defects, whereas infection with phage in which the gp11 gene has been deleted showed a significant increase in lipid II production in S. aureus. Together, our findings reveal that a phage early-gene product interacts with essential host proteins to disrupt PG biosynthesis and block S. aureus cell division, suggesting a potential pathway for the development of therapeutic approaches to treat pathogenic bacterial infections. IMPORTANCE Understanding the interplay between phages and their hosts is important for the development of novel therapies against pathogenic bacteria. Although phages have been used to control methicillin-resistant Staphylococcus aureus infections, our knowledge related to the processes in the early stages of phage infection is still limited. Owing to the fact that most of the phage early proteins have been classified as hypothetical proteins with uncertain functions, we screened phage early-gene products that inhibit cell growth in S. aureus, and one protein, Gp11, selectively targets essential host genes to block the synthesis of the peptidoglycan component lipid II, ultimately leading to cell growth arrest in S. aureus. Our study provides a novel insight into the strategy by which Gp11 blocks essential host cellular metabolism to influence phage-host interaction. Importantly, dissecting the interactions between phages and host cells will contribute to the development of new and effective therapies to treat bacterial infections.
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Affiliation(s)
- Qi Xu
- CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Li Tang
- CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Weilin Liu
- CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China
| | - Neng Xu
- CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China
| | - Yangbo Hu
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China
| | - Yong Zhang
- CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China
| | - Shiyun Chen
- CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China
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Tuck OT, Adler BA, Armbruster EG, Lahiri A, Hu JJ, Zhou J, Pogliano J, Doudna JA. Hachiman is a genome integrity sensor. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.29.582594. [PMID: 38464307 PMCID: PMC10925250 DOI: 10.1101/2024.02.29.582594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Hachiman is a broad-spectrum antiphage defense system of unknown function. We show here that Hachiman comprises a heterodimeric nuclease-helicase complex, HamAB. HamA, previously a protein of unknown function, is the effector nuclease. HamB is the sensor helicase. HamB constrains HamA activity during surveillance of intact dsDNA. When the HamAB complex detects DNA damage, HamB helicase activity liberates HamA, unleashing nuclease activity. Hachiman activation degrades all DNA in the cell, creating 'phantom' cells devoid of both phage and host DNA. We demonstrate Hachiman activation in the absence of phage by treatment with DNA-damaging agents, suggesting that Hachiman responds to aberrant DNA states. Phylogenetic similarities between the Hachiman helicase and eukaryotic enzymes suggest this bacterial immune system has been repurposed for diverse functions across all domains of life.
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Affiliation(s)
- Owen T. Tuck
- Department of Chemistry, University of California, Berkeley, Berkeley, CA USA
- Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA USA
| | - Benjamin A. Adler
- Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA USA
- California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, CA USA
| | - Emily G. Armbruster
- School of Biological Sciences, University of California San Diego, La Jolla, CA USA
| | - Arushi Lahiri
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California USA
| | - Jason J. Hu
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California USA
| | - Julia Zhou
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California USA
| | - Joe Pogliano
- School of Biological Sciences, University of California San Diego, La Jolla, CA USA
| | - Jennifer A. Doudna
- Department of Chemistry, University of California, Berkeley, Berkeley, CA USA
- Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA USA
- California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, CA USA
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California USA
- Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA USA
- MBIB Division, Lawrence Berkeley National Laboratory, Berkeley, CA USA
- Gladstone Institutes, University of California, San Francisco, San Francisco, CA USA
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA USA
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3
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Antonova D, Belousova VV, Zhivkoplias E, Sobinina M, Artamonova T, Vishnyakov IE, Kurdyumova I, Arseniev A, Morozova N, Severinov K, Khodorkovskii M, Yakunina MV. The Dynamics of Synthesis and Localization of Jumbo Phage RNA Polymerases inside Infected Cells. Viruses 2023; 15:2096. [PMID: 37896872 PMCID: PMC10612078 DOI: 10.3390/v15102096] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 10/06/2023] [Accepted: 10/11/2023] [Indexed: 10/29/2023] Open
Abstract
A nucleus-like structure composed of phage-encoded proteins and containing replicating viral DNA is formed in Pseudomonas aeruginosa cells infected by jumbo bacteriophage phiKZ. The PhiKZ genes are transcribed independently from host RNA polymerase (RNAP) by two RNAPs encoded by the phage. The virion RNAP (vRNAP) transcribes early viral genes and must be injected into the cell with phage DNA. The non-virion RNAP (nvRNAP) is composed of early gene products and transcribes late viral genes. In this work, the dynamics of phage RNAPs localization during phage phiKZ infection were studied. We provide direct evidence of PhiKZ vRNAP injection in infected cells and show that it is excluded from the phage nucleus. The nvRNAP is synthesized shortly after the onset of infection and localizes in the nucleus. We propose that spatial separation of two phage RNAPs allows coordinated expression of phage genes belonging to different temporal classes.
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Affiliation(s)
- Daria Antonova
- Research Center of Nanobiotechnologies, Peter the Great St. Petersburg Polytechnic University, St. Petersburg 195251, Russia
| | - Viktoriia V. Belousova
- Research Center of Nanobiotechnologies, Peter the Great St. Petersburg Polytechnic University, St. Petersburg 195251, Russia
| | - Erik Zhivkoplias
- Research Center of Nanobiotechnologies, Peter the Great St. Petersburg Polytechnic University, St. Petersburg 195251, Russia
| | - Mariia Sobinina
- Research Center of Nanobiotechnologies, Peter the Great St. Petersburg Polytechnic University, St. Petersburg 195251, Russia
| | - Tatyana Artamonova
- Research Center of Nanobiotechnologies, Peter the Great St. Petersburg Polytechnic University, St. Petersburg 195251, Russia
| | - Innokentii E. Vishnyakov
- Group of Molecular Cytology of Prokaryotes and Bacterial Invasion, Institute of Cytology of the Russian Academy of Science, St. Petersburg 194064, Russia;
| | - Inna Kurdyumova
- Research Center of Nanobiotechnologies, Peter the Great St. Petersburg Polytechnic University, St. Petersburg 195251, Russia
| | - Anatoly Arseniev
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology Russian Academy of Sciences, Moscow 119334, Russia
| | - Natalia Morozova
- Research Center of Nanobiotechnologies, Peter the Great St. Petersburg Polytechnic University, St. Petersburg 195251, Russia
| | - Konstantin Severinov
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology Russian Academy of Sciences, Moscow 119334, Russia
- Institute of Molecular Genetics National Kurchatov Center, Moscow 123182, Russia
- Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
| | - Mikhail Khodorkovskii
- Research Center of Nanobiotechnologies, Peter the Great St. Petersburg Polytechnic University, St. Petersburg 195251, Russia
| | - Maria V. Yakunina
- Research Center of Nanobiotechnologies, Peter the Great St. Petersburg Polytechnic University, St. Petersburg 195251, Russia
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Gao Z, Feng Y. Bacteriophage strategies for overcoming host antiviral immunity. Front Microbiol 2023; 14:1211793. [PMID: 37362940 PMCID: PMC10286901 DOI: 10.3389/fmicb.2023.1211793] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 05/17/2023] [Indexed: 06/28/2023] Open
Abstract
Phages and their bacterial hosts together constitute a vast and diverse ecosystem. Facing the infection of phages, prokaryotes have evolved a wide range of antiviral mechanisms, and phages in turn have adopted multiple tactics to circumvent or subvert these mechanisms to survive. An in-depth investigation into the interaction between phages and bacteria not only provides new insight into the ancient coevolutionary conflict between them but also produces precision biotechnological tools based on anti-phage systems. Moreover, a more complete understanding of their interaction is also critical for the phage-based antibacterial measures. Compared to the bacterial antiviral mechanisms, studies into counter-defense strategies adopted by phages have been a little slow, but have also achieved important advances in recent years. In this review, we highlight the numerous intracellular immune systems of bacteria as well as the countermeasures employed by phages, with an emphasis on the bacteriophage strategies in response to host antiviral immunity.
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Abstract
By entering a reversible state of reduced metabolic activity, dormant microorganisms are able to tolerate suboptimal conditions that would otherwise reduce their fitness. Dormancy may also benefit bacteria by serving as a refuge from parasitic infections. Here, we focus on dormancy in the Bacillota, where endospore development is transcriptionally regulated by the expression of sigma factors. A disruption of this process could influence the survivorship or reproduction of phages that infect spore-forming hosts with implications for coevolutionary dynamics. We characterized the distribution of sigma factors in over 4,000 genomes of diverse phages capable of infecting hosts that span the bacterial domain. From this, we identified homologs of sporulation-specific sigma factors in phages that infect spore-forming hosts. Unlike sigma factors required for phage reproduction, we provide evidence that sporulation-like sigma factors are nonessential for lytic infection. However, when expressed in the spore-forming Bacillus subtilis, some of these phage-derived sigma factors can activate the bacterial sporulation gene network and lead to a reduction in spore yield. Our findings suggest that the acquisition of host-like transcriptional regulators may allow phages to manipulate a complex and ancient trait in one of the most abundant cell types on Earth. IMPORTANCE As obligate parasites, phages exert strong top-down pressure on host populations with eco-evolutionary implications for community dynamics and ecosystem functioning. The process of phage infection, however, is constrained by bottom-up processes that influence the energetic and nutritional status of susceptible hosts. Many phages have acquired auxiliary genes from bacteria, which can be used to exploit host metabolism with consequences for phage fitness. In this study, we demonstrate that phages infecting spore-forming bacteria carry homologs of sigma factors, which their hosts use to orchestrate gene expression during spore development. By tapping into regulatory gene networks, phages may manipulate the physiology and survival strategies of nongrowing bacteria in ways that influence host-parasite coevolution.
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6
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Bacteria deplete deoxynucleotides to defend against bacteriophage infection. Nat Microbiol 2022; 7:1200-1209. [PMID: 35817891 DOI: 10.1038/s41564-022-01158-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 05/23/2022] [Indexed: 11/09/2022]
Abstract
DNA viruses and retroviruses consume large quantities of deoxynucleotides (dNTPs) when replicating. The human antiviral factor SAMHD1 takes advantage of this vulnerability in the viral lifecycle, and inhibits viral replication by degrading dNTPs into their constituent deoxynucleosides and inorganic phosphate. Here, we report that bacteria use a similar strategy to defend against bacteriophage infection. We identify a family of defensive bacterial deoxycytidine triphosphate (dCTP) deaminase proteins that convert dCTP into deoxyuracil nucleotides in response to phage infection. We also identify a family of phage resistance genes that encode deoxyguanosine triphosphatase (dGTPase) enzymes, which degrade dGTP into phosphate-free deoxyguanosine and are distant homologues of human SAMHD1. Our results suggest that bacterial defensive proteins deplete specific deoxynucleotides (either dCTP or dGTP) from the nucleotide pool during phage infection, thus starving the phage of an essential DNA building block and halting its replication. Our study shows that manipulation of the dNTP pool is a potent antiviral strategy shared by both prokaryotes and eukaryotes.
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Sengupta S, Bhawsinghka N, Shaw R, Patra MM, Das Gupta SK. Mycobacteriophage D29 induced association of Mycobacterial RNA polymerase with ancillary factors leads to increased transcriptional activity. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 35353035 DOI: 10.1099/mic.0.001158] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Mycobacteriophage D29 infects species belonging to the genus Mycobacterium including the deadly pathogen Mycobacterium tuberculosis. D29 is a lytic phage, although, related to the lysogenic mycobacteriophage L5. This phage is unable to lysogenize in mycobacteria as it lacks the gene encoding the phage repressor. Infection by many mycobacteriophages cause various changes in the host that ultimately leads to inactivation of the latter. One of the host targets often modified in the process is RNA polymerase. During our investigations with phage D29 infected Mycobacterium smegmatis (Msm) we observed that the promoters from both phage, and to a lesser extent those of the host were found to be more active in cells that were exposed to D29, as compared to the unexposed. Further experiments indicate that the RNA polymerase purified from phage infected cells possessed higher affinity for promoters particularly those that were phage derived. Comparison of the purified RNA polymerase preparations from infected and uninfected cells showed that several ancillary transcription factors, Sigma factor F, Sigma factor H, CarD and RbpA are prominently associated with the RNA polymerase from infected cells. Based on our observations we conclude that the higher activity of RNA polymerase observed in D29 infected cells is due to its increased association with ancillary transcription factors.
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Affiliation(s)
- Shreya Sengupta
- Department of Microbiology, Bose Institute, P-1/12 C.I.T Road. Scheme VIIM, Kolkata-700054, West Bengal, India
| | - Niketa Bhawsinghka
- Department of Microbiology, Bose Institute, P-1/12 C.I.T Road. Scheme VIIM, Kolkata-700054, West Bengal, India.,Present address: Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Rahul Shaw
- Department of Microbiology, Bose Institute, P-1/12 C.I.T Road. Scheme VIIM, Kolkata-700054, West Bengal, India
| | - Madhu Manti Patra
- Department of Microbiology, Bose Institute, P-1/12 C.I.T Road. Scheme VIIM, Kolkata-700054, West Bengal, India
| | - Sujoy K Das Gupta
- Department of Microbiology, Bose Institute, P-1/12 C.I.T Road. Scheme VIIM, Kolkata-700054, West Bengal, India
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8
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Malone LM, Hampton HG, Morgan XC, Fineran PC. Type I CRISPR-Cas provides robust immunity but incomplete attenuation of phage-induced cellular stress. Nucleic Acids Res 2021; 50:160-174. [PMID: 34928385 PMCID: PMC8754663 DOI: 10.1093/nar/gkab1210] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 11/09/2021] [Accepted: 11/23/2021] [Indexed: 11/14/2022] Open
Abstract
During infection, phages manipulate bacteria to redirect metabolism towards viral proliferation. To counteract phages, some bacteria employ CRISPR-Cas systems that provide adaptive immunity. While CRISPR-Cas mechanisms have been studied extensively, their effects on both the phage and the host during phage infection remains poorly understood. Here, we analysed the infection of Serratia by a siphovirus (JS26) and the transcriptomic response with, or without type I-E or I-F CRISPR-Cas immunity. In non-immune Serratia, phage infection altered bacterial metabolism by upregulating anaerobic respiration and amino acid biosynthesis genes, while flagella production was suppressed. Furthermore, phage proliferation required a late-expressed viral Cas4 homologue, which did not influence CRISPR adaptation. While type I-E and I-F immunity provided robust defence against phage infection, phage development still impacted the bacterial host. Moreover, DNA repair and SOS response pathways were upregulated during type I immunity. We also discovered that the type I-F system is controlled by a positive autoregulatory feedback loop that is activated upon phage targeting during type I-F immunity, leading to a controlled anti-phage response. Overall, our results provide new insight into phage-host dynamics and the impact of CRISPR immunity within the infected cell.
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Affiliation(s)
- Lucia M Malone
- Department of Microbiology and Immunology, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Hannah G Hampton
- Department of Microbiology and Immunology, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Xochitl C Morgan
- Department of Microbiology and Immunology, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Peter C Fineran
- Department of Microbiology and Immunology, University of Otago, PO Box 56, Dunedin 9054, New Zealand
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Bajaj JS, Sikaroodi M, Shamsaddini A, Henseler Z, Santiago-Rodriguez T, Acharya C, Fagan A, Hylemon PB, Fuchs M, Gavis E, Ward T, Knights D, Gillevet PM. Interaction of bacterial metagenome and virome in patients with cirrhosis and hepatic encephalopathy. Gut 2021; 70:1162-1173. [PMID: 32998876 DOI: 10.1136/gutjnl-2020-322470] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 08/18/2020] [Accepted: 08/30/2020] [Indexed: 02/06/2023]
Abstract
OBJECTIVE Altered bacterial composition is associated with disease progression in cirrhosis but the role of virome, especially phages, is unclear. DESIGN Cross-sectional and pre/post rifaximin cohorts were enrolled. Cross-sectional: controls and cirrhotic outpatients (compensated, on lactulose (Cirr-L), on rifaximin (Cirr-LR)) were included and followed for 90-day hospitalisations. Pre/post: compensated cirrhotics underwent stool collection pre/post 8 weeks of rifaximin. Stool metagenomics for bacteria and phages and their correlation networks were analysed in controls versus cirrhosis, within cirrhotics, hospitalised/not and pre/post rifaximin. RESULTS Cross-sectional: 40 controls and 163 cirrhotics (63 compensated, 43 Cirr-L, 57 Cirr-LR) were enrolled. Cirr-L/LR groups were similar on model for end-stage liver disease (MELD) score but Cirr-L developed greater hospitalisations versus Cirr-LR (56% vs 30%, p=0.008). Bacterial alpha/beta diversity worsened from controls through Cirr-LR. While phage alpha diversity was similar, beta diversity was different between groups. Autochthonous bacteria linked negatively, pathobionts linked positively with MELD but only modest phage-MELD correlations were seen. Phage-bacterial correlation network complexity was highest in controls, lowest in Cirr-L and increased in Cirr-LR. Microviridae and Faecalibacterium phages were linked with autochthonous bacteria in Cirr-LR, but not Cirr-L hospitalised patients had greater pathobionts, lower commensal bacteria and phages focused on Streptococcus, Lactococcus and Myoviridae. Pre/post: No changes in alpha/beta diversity of phages or bacteria were seen postrifaximin. Phage-bacterial linkages centred around urease-producing Streptococcus species collapsed postrifaximin. CONCLUSION Unlike bacteria, faecal phages are sparsely linked with cirrhosis characteristics and 90-day outcomes. Phage and bacterial linkages centred on urease-producing, ammonia-generating Streptococcus species were affected by disease progression and rifaximin therapy and were altered in patients who experienced 90-day hospitalisations.
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Affiliation(s)
- Jasmohan S Bajaj
- Gastroenterology, Hepatology and Nutrition, Virginia Commonwealth University and Central Virginia Veterans Healthcare System, Richmond, Virginia, USA
| | - Masoumeh Sikaroodi
- Microbiome Analysis Center, George Mason University, Manassas, Virginia, USA
| | | | | | | | - Chathur Acharya
- Gastroenterology, Hepatology and Nutrition, Virginia Commonwealth University and Central Virginia Veterans Healthcare System, Richmond, Virginia, USA
| | - Andrew Fagan
- Gastroenterology, Hepatology and Nutrition, Virginia Commonwealth University and Central Virginia Veterans Healthcare System, Richmond, Virginia, USA
| | - Phillip B Hylemon
- Gastroenterology, Hepatology and Nutrition, Virginia Commonwealth University and Central Virginia Veterans Healthcare System, Richmond, Virginia, USA
| | - Michael Fuchs
- Gastroenterology, Hepatology and Nutrition, Virginia Commonwealth University and Central Virginia Veterans Healthcare System, Richmond, Virginia, USA
| | - Edith Gavis
- Gastroenterology, Hepatology and Nutrition, Virginia Commonwealth University and Central Virginia Veterans Healthcare System, Richmond, Virginia, USA
| | - Tonya Ward
- Diversigen, New Brighton, Minnesota, USA
| | - Dan Knights
- Diversigen, New Brighton, Minnesota, USA.,Department of Computer Science and Engineering, U, University of Minnesota, Minneapolis, MN, USA.,Minnesota Biotechnology Institute, University of Minnesota, Minneapolis, MN, USA
| | - Patrick M Gillevet
- Microbiome Analysis Center, George Mason University, Manassas, Virginia, USA
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Casas-Pastor D, Müller RR, Jaenicke S, Brinkrolf K, Becker A, Buttner MJ, Gross CA, Mascher T, Goesmann A, Fritz G. Expansion and re-classification of the extracytoplasmic function (ECF) σ factor family. Nucleic Acids Res 2021; 49:986-1005. [PMID: 33398323 PMCID: PMC7826278 DOI: 10.1093/nar/gkaa1229] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 12/01/2020] [Accepted: 12/07/2020] [Indexed: 12/15/2022] Open
Abstract
Extracytoplasmic function σ factors (ECFs) represent one of the major bacterial signal transduction mechanisms in terms of abundance, diversity and importance, particularly in mediating stress responses. Here, we performed a comprehensive phylogenetic analysis of this protein family by scrutinizing all proteins in the NCBI database. As a result, we identified an average of ∼10 ECFs per bacterial genome and 157 phylogenetic ECF groups that feature a conserved genetic neighborhood and a similar regulation mechanism. Our analysis expands previous classification efforts ∼50-fold, enriches many original ECF groups with previously unclassified proteins and identifies 22 entirely new ECF groups. The ECF groups are hierarchically related to each other and are further composed of subgroups with closely related sequences. This two-tiered classification allows for the accurate prediction of common promoter motifs and the inference of putative regulatory mechanisms across subgroups composing an ECF group. This comprehensive, high-resolution description of the phylogenetic distribution of the ECF family, together with the massive expansion of classified ECF sequences and an openly accessible data repository called ‘ECF Hub’ (https://www.computational.bio.uni-giessen.de/ecfhub), will serve as a powerful hypothesis-generator to guide future research in the field.
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Affiliation(s)
- Delia Casas-Pastor
- Center for Synthetic Microbiology (SYNMIKRO), Philipps Universität Marburg, Germany
| | - Raphael R Müller
- Bioinformatics and Systems Biology, Justus-Liebig-Universität, Giessen, Germany
| | - Sebastian Jaenicke
- Bioinformatics and Systems Biology, Justus-Liebig-Universität, Giessen, Germany
| | - Karina Brinkrolf
- Bioinformatics and Systems Biology, Justus-Liebig-Universität, Giessen, Germany
| | - Anke Becker
- Center for Synthetic Microbiology (SYNMIKRO), Philipps Universität Marburg, Germany
| | - Mark J Buttner
- Department of Molecular Microbiology, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Carol A Gross
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94158, USA; Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, CA 94158, USA; California Institute of Quantitative Biology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Thorsten Mascher
- Institute of Microbiology, Technische Universität Dresden, Germany
| | - Alexander Goesmann
- Bioinformatics and Systems Biology, Justus-Liebig-Universität, Giessen, Germany
| | - Georg Fritz
- School of Molecular Sciences, The University of Western Australia, Perth, Western Australia 6009, Australia
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11
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Chen Y, Zeng Q. Temporal transcriptional patterns of cyanophage genes suggest synchronized infection of cyanobacteria in the oceans. MICROBIOME 2020; 8:68. [PMID: 32430017 PMCID: PMC7238727 DOI: 10.1186/s40168-020-00842-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 04/15/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Based on the peak expression times during infection, early, middle, and late genes have been characterized in viruses (cyanophages) that infect the unicellular cyanobacterium Prochlorococcus. Laboratory experiments show that some cyanophages can only replicate in the light and thus exhibit diurnal infection rhythms under light-dark cycles. Field evidence also suggests synchronized infection of Prochlorococcus by cyanophages in the oceans, which should result in progressive expression of cyanophage early, middle, and late genes. However, distinct temporal expression patterns have not been observed in cyanophage field populations. RESULTS In this study, we reanalyzed a previous metatranscriptomic dataset collected in the North Pacific Subtropical Gyre. In this dataset, it was previously shown that aggregate transcripts from cyanophage scaffolds display diurnal transcriptional rhythms with transcript abundances decreasing at night. By mapping metatranscriptomic reads to individual viral genes, we identified periodically expressed genes from putative viruses infecting the cyanobacteria Prochlorococcus and Synechococcus, heterotrophic bacteria, and algae. Of the 41 cyanophage genes, 35 were from cyanomyoviruses. We grouped the periodically expressed cyanomyovirus genes into early, middle, and late genes based on the conserved temporal expression patterns of their orthologs in cyanomyovirus laboratory cultures. We found that the peak expression times of late genes in cyanophage field populations were significantly later than those of early and middle genes, which were similar to the temporal expression patterns of synchronized cyanophage laboratory cultures. CONCLUSIONS The significantly later peak expression times of late genes in cyanomyovirus field populations suggest that cyanophage infection of Prochlorococcus is synchronized in the North Pacific Subtropical Gyre. The night-time peak expression of late genes also suggests synchronized lysis of Prochlorococcus at night, which might result in synchronized release of dissolved organic matter to the marine food web. Video abstract.
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Affiliation(s)
- Yue Chen
- Department of Ocean Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Qinglu Zeng
- Department of Ocean Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
- HKUST Shenzhen Research Institute, Shenzhen, China.
- Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
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12
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Shi X, Zhao F, Sun H, Yu X, Zhang C, Liu W, Pan Q, Ren H. Characterization and Complete Genome Analysis of Pseudomonas aeruginosa Bacteriophage vB_PaeP_LP14 Belonging to Genus Litunavirus. Curr Microbiol 2020; 77:2465-2474. [PMID: 32367280 DOI: 10.1007/s00284-020-02011-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 04/24/2020] [Indexed: 12/17/2022]
Abstract
A lytic Pseudomonas aeruginosa phage vB_PaeP_LP14 belonging to the family Podoviridae was isolated from infected mink. The microbiological characterization revealed that LP14 was stable at 40 to 50 °C and stable over a broad range of pH (5 to 12). The latent period was 5 min, and the burst size was 785 pfu/infected cell. The whole-genome sequencing showed that LP14 was a dsDNA virus and has a genome of 73,080 bp. The genome contained 93 predicted open reading frames (ORFs), 17 of which have known functions including DNA replication and modification, transcriptional regulation, structural and packaging proteins, and host cell lysis. No tRNA genes were identified. BLASTn analysis revealed that phage LP14 had a high-sequence identity (96%) with P. aeruginosa phage YH6. Both morphological characterization and genome annotation indicate that phage LP14 is a memberof the family Podoviridae genus Litunavirus. The study of phage LP14 will provide basic information for further research on treatment of P. aeruginosa infections.
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Affiliation(s)
- Xiaojie Shi
- College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, Shandong, China
| | - Feiyang Zhao
- College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, Shandong, China
| | - Huzhi Sun
- Qingdao Phagepharm Bio-tech Co, Ltd, Qingdao, Shandong, China
| | - Xiaoyan Yu
- College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, Shandong, China
| | - Can Zhang
- College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, Shandong, China
| | - Wenhua Liu
- College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, Shandong, China
| | - Qiang Pan
- Qingdao Phagepharm Bio-tech Co, Ltd, Qingdao, Shandong, China
| | - Huiying Ren
- College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, Shandong, China.
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13
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Weissman JL, Stoltzfus A, Westra ER, Johnson PLF. Avoidance of Self during CRISPR Immunization. Trends Microbiol 2020; 28:543-553. [PMID: 32544441 DOI: 10.1016/j.tim.2020.02.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 02/05/2020] [Accepted: 02/25/2020] [Indexed: 02/07/2023]
Abstract
The battle between microbes and their viruses is ancient and ongoing. Clustered regularly interspaced short palindromic repeat (CRISPR) immunity, the first and, to date, only form of adaptive immunity found in prokaryotes, represents a flexible mechanism to recall past infections while also adapting to a changing pathogenic environment. Critical to the role of CRISPR as an adaptive immune mechanism is its capacity for self versus non-self recognition when acquiring novel immune memories. Yet, CRISPR systems vary widely in both how and to what degree they can distinguish foreign from self-derived genetic material. We document known and hypothesized mechanisms that bias the acquisition of immune memory towards non-self targets. We demonstrate that diversity is the rule, with many widespread but no universal mechanisms for self versus non-self recognition.
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Affiliation(s)
- Jake L Weissman
- Department of Biology, University of Maryland, College Park, MD, USA
| | - Arlin Stoltzfus
- Office of Data and Informatics, Material Measurement Laboratory, NIST, Gaithersburg, MD 20899, USA; Institute for Bioscience and Biotechnology Research, 9600 Gudelsky Drive, Rockville, MD 20850, USA
| | - Edze R Westra
- Environment and Sustainability Institute, Centre for Ecology and Conservation, University of Exeter, Biosciences, Penryn, Cornwall, UK
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14
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Hutinet G, Kot W, Cui L, Hillebrand R, Balamkundu S, Gnanakalai S, Neelakandan R, Carstens AB, Fa Lui C, Tremblay D, Jacobs-Sera D, Sassanfar M, Lee YJ, Weigele P, Moineau S, Hatfull GF, Dedon PC, Hansen LH, de Crécy-Lagard V. 7-Deazaguanine modifications protect phage DNA from host restriction systems. Nat Commun 2019; 10:5442. [PMID: 31784519 PMCID: PMC6884629 DOI: 10.1038/s41467-019-13384-y] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 11/04/2019] [Indexed: 12/14/2022] Open
Abstract
Genome modifications are central components of the continuous arms race between viruses and their hosts. The archaeosine base (G+), which was thought to be found only in archaeal tRNAs, was recently detected in genomic DNA of Enterobacteria phage 9g and was proposed to protect phage DNA from a wide variety of restriction enzymes. In this study, we identify three additional 2'-deoxy-7-deazaguanine modifications, which are all intermediates of the same pathway, in viruses: 2'-deoxy-7-amido-7-deazaguanine (dADG), 2'-deoxy-7-cyano-7-deazaguanine (dPreQ0) and 2'-deoxy-7- aminomethyl-7-deazaguanine (dPreQ1). We identify 180 phages or archaeal viruses that encode at least one of the enzymes of this pathway with an overrepresentation (60%) of viruses potentially infecting pathogenic microbial hosts. Genetic studies with the Escherichia phage CAjan show that DpdA is essential to insert the 7-deazaguanine base in phage genomic DNA and that 2'-deoxy-7-deazaguanine modifications protect phage DNA from host restriction enzymes.
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Affiliation(s)
- Geoffrey Hutinet
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, 32611, USA.
| | - Witold Kot
- Department of Environmental Science, Aarhus University, Roskilde, Denmark
| | - Liang Cui
- Singapore-MIT Alliance for Research and Technology, Antimicrobial Resistance Interdisciplinary Research Group, Campus for Research Excellence and Technological Enterprise, Singapore, 138602, Singapore
| | - Roman Hillebrand
- Department of Biological Engineering and Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Nitto Denko Avecia, 125 Fortune Boulevard, Milford, MA, 01757, USA
| | - Seetharamsingh Balamkundu
- Singapore-MIT Alliance for Research and Technology, Antimicrobial Resistance Interdisciplinary Research Group, Campus for Research Excellence and Technological Enterprise, Singapore, 138602, Singapore
| | - Shanmugavel Gnanakalai
- Singapore-MIT Alliance for Research and Technology, Antimicrobial Resistance Interdisciplinary Research Group, Campus for Research Excellence and Technological Enterprise, Singapore, 138602, Singapore
| | - Ramesh Neelakandan
- Singapore-MIT Alliance for Research and Technology, Antimicrobial Resistance Interdisciplinary Research Group, Campus for Research Excellence and Technological Enterprise, Singapore, 138602, Singapore
| | | | - Chuan Fa Lui
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Singapore
| | - Denise Tremblay
- Département de Biochimie, Microbiologie et de Bio-informatique, Faculté des Sciences et de Génie, Université Laval, Québec City, QC, G1V 0A6, Canada
- Félix d'Hérelle Reference Center for Bacterial Viruses and Groupe de Recherche en Écologie Buccale, Faculté de Médecine Dentaire, Université Laval, Québec City, QC, G1V 0A6, Canada
| | - Deborah Jacobs-Sera
- Pittsburgh Bacteriophage Institute and Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Mandana Sassanfar
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Yan-Jiun Lee
- Research Department, New England Biolabs, Ipswich, MA, 01938, USA
| | - Peter Weigele
- Research Department, New England Biolabs, Ipswich, MA, 01938, USA
| | - Sylvain Moineau
- Département de Biochimie, Microbiologie et de Bio-informatique, Faculté des Sciences et de Génie, Université Laval, Québec City, QC, G1V 0A6, Canada
- Félix d'Hérelle Reference Center for Bacterial Viruses and Groupe de Recherche en Écologie Buccale, Faculté de Médecine Dentaire, Université Laval, Québec City, QC, G1V 0A6, Canada
| | - Graham F Hatfull
- Pittsburgh Bacteriophage Institute and Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Peter C Dedon
- Singapore-MIT Alliance for Research and Technology, Antimicrobial Resistance Interdisciplinary Research Group, Campus for Research Excellence and Technological Enterprise, Singapore, 138602, Singapore
- Department of Biological Engineering and Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Lars H Hansen
- Department of Environmental Science, Aarhus University, Roskilde, Denmark
| | - Valérie de Crécy-Lagard
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, 32611, USA.
- University of Florida, Genetics Institute, Gainesville, Florida, 32610, USA.
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15
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Abstract
Bacteriophages employ small proteins to usurp host molecular machinery, thereby interfering with central metabolic processes in infected bacteria. Generally, phages inhibit or redirect host transcription to favor transcription of their own genomes. Mechanistic and structural studies of phage-modulated host transcription may provide inspirations for the development of novel antibacterial substances.
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Affiliation(s)
- Markus C Wahl
- Freie Universität Berlin, Laboratory of Structural Biochemistry, Berlin, Germany.,Helmholtz-Zentrum Berlin für Materialien und Energie, Macromolecular Crystallography, Berlin, Germany
| | - Ranjan Sen
- Laboratory of Transcription, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, India
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16
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Tabib-Salazar A, Mulvenna N, Severinov K, Matthews SJ, Wigneshweraraj S. Xenogeneic Regulation of the Bacterial Transcription Machinery. J Mol Biol 2019; 431:4078-4092. [DOI: 10.1016/j.jmb.2019.02.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 01/30/2019] [Accepted: 02/06/2019] [Indexed: 10/27/2022]
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17
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Structural basis for transcription antitermination at bacterial intrinsic terminator. Nat Commun 2019; 10:3048. [PMID: 31296855 PMCID: PMC6624301 DOI: 10.1038/s41467-019-10955-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 05/29/2019] [Indexed: 01/25/2023] Open
Abstract
Bacteriophages typically hijack the host bacterial transcriptional machinery to regulate their own gene expression and that of the host bacteria. The structural basis for bacteriophage protein-mediated transcription regulation—in particular transcription antitermination—is largely unknown. Here we report the 3.4 Å and 4.0 Å cryo-EM structures of two bacterial transcription elongation complexes (P7-NusA-TEC and P7-TEC) comprising the bacteriophage protein P7, a master host-transcription regulator encoded by bacteriophage Xp10 of the rice pathogen Xanthomonas oryzae pv. Oryzae (Xoo) and discuss the mechanisms by which P7 modulates the host bacterial RNAP. The structures together with biochemical evidence demonstrate that P7 prevents transcription termination by plugging up the RNAP RNA-exit channel and impeding RNA-hairpin formation at the intrinsic terminator. Moreover, P7 inhibits transcription initiation by restraining RNAP-clamp motions. Our study reveals the structural basis for transcription antitermination by phage proteins and provides insights into bacterial transcription regulation. Bacteriophages reprogram the host transcriptional machinery. Here the authors provide insights into the mechanism of how bacteriophages regulate host transcription by determining the cryo-EM structures of two bacterial transcription elongation complexes bound with the bacteriophage master host-transcription regulator protein P7.
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18
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Bacteriophage gene products as potential antimicrobials against tuberculosis. Biochem Soc Trans 2019; 47:847-860. [PMID: 31085613 DOI: 10.1042/bst20180506] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 04/02/2019] [Accepted: 04/08/2019] [Indexed: 01/20/2023]
Abstract
Tuberculosis (TB) is recognised as one of the most pressing global health threats among infectious diseases. Bacteriophages are adapted for killing of their host, and they were exploited in antibacterial therapy already before the discovery of antibiotics. Antibiotics as broadly active drugs overshadowed phage therapy for a long time. However, owing to the rapid spread of antibiotic resistance and the increasing complexity of treatment of drug-resistant TB, mycobacteriophages are being studied for their antimicrobial potential. Besides phage therapy, which is the administration of live phages to infected patients, the development of drugs of phage origin is gaining interest. This path of medical research might provide us with a new pool of previously undiscovered inhibition mechanisms and molecular interactions which are also of interest in basic research of cellular processes, such as transcription. The current state of research on mycobacteriophage-derived anti-TB treatment is reviewed in comparison with inhibitors from other phages, and with focus on transcription as the host target process.
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19
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Characterization and genome analysis of a novel bacteriophage vB_SpuP_Spp16 that infects Salmonella enterica serovar pullorum. Virus Genes 2019; 55:532-540. [PMID: 31004278 DOI: 10.1007/s11262-019-01664-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 04/14/2019] [Indexed: 10/27/2022]
Abstract
A novel virulent bacteriophage vB_SpuP_Spp16 (hereafter designated Spp16) that infects Salmonella enterica serovar pullorum was isolated. Transmission electron microscopy showed that Spp16 possessed an isometric polyhedral head (60 nm in diameter) and a short tail (10 nm in length) belonging to the family Podoviridae. Its complete genome was determined to be 41,832 bp, with a 39.46% GC content by next-generation sequencing. The genome contains 53 proposed open reading frames that are involved in DNA replication and modification, transcriptional regulation, phage structural and packaging proteins and bacterial lysis. No transfer RNA genes were identified. The termini of genome were determined using our previously proposed termini identification method, which suggests that this phage has redundant termini with 421 bp direct terminal repeats. BLASTn analysis revealed the highest sequence similarity with Yersinia phage phi80-18, with a genome coverage of 33% and highest sequence identity of 69%. The phylogenetic analysis indicated that Spp16 forms a distinct branch of the subfamily Autographivirinae. Comparative genomics analysis showed that the phage Spp16 should be regarded as a new subcluster within the GAP227-like cluster in the Autographivirinae subfamily. The phage Spp16 has an obligate lytic life cycle demonstrated by experimental data and genomic analysis. These results suggest that Spp16 may be a proper candidate to control diseases caused by Salmonella enterica serovar pullorum.
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20
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Numerous cultivated and uncultivated viruses encode ribosomal proteins. Nat Commun 2019; 10:752. [PMID: 30765709 PMCID: PMC6375957 DOI: 10.1038/s41467-019-08672-6] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 01/18/2019] [Indexed: 01/04/2023] Open
Abstract
Viruses modulate ecosystems by directly altering host metabolisms through auxiliary metabolic genes. However, viral genomes are not known to encode the core components of translation machinery, such as ribosomal proteins (RPs). Here, using reference genomes and global-scale viral metagenomic datasets, we identify 14 different RPs across viral genomes arising from cultivated viral isolates and metagenome-assembled viruses. Viruses tend to encode dynamic RPs, easily exchangeable between ribosomes, suggesting these proteins can replace cellular versions in host ribosomes. Functional assays confirm that the two most common virus-encoded RPs, bS21 and bL12, are incorporated into 70S ribosomes when expressed in Escherichia coli. Ecological distribution of virus-encoded RPs suggests some level of ecosystem adaptations as aquatic viruses and viruses of animal-associated bacteria are enriched for different subsets of RPs. Finally, RP genes are under purifying selection and thus likely retained an important function after being horizontally transferred into virus genomes.
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21
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Wandro S, Oliver A, Gallagher T, Weihe C, England W, Martiny JBH, Whiteson K. Predictable Molecular Adaptation of Coevolving Enterococcus faecium and Lytic Phage EfV12-phi1. Front Microbiol 2019; 9:3192. [PMID: 30766528 PMCID: PMC6365445 DOI: 10.3389/fmicb.2018.03192] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 12/10/2018] [Indexed: 01/21/2023] Open
Abstract
Bacteriophages are highly abundant in human microbiota where they coevolve with resident bacteria. Phage predation can drive the evolution of bacterial resistance, which can then drive reciprocal evolution in the phage to overcome that resistance. Such coevolutionary dynamics have not been extensively studied in human gut bacteria, and are of particular interest for both understanding and eventually manipulating the human gut microbiome. We performed experimental evolution of an Enterococcus faecium isolate from healthy human stool in the absence and presence of a single infecting Myoviridae bacteriophage, EfV12-phi1. Four replicates of E. faecium and phage were grown with twice daily serial transfers for 8 days. Genome sequencing revealed that E. faecium evolved resistance to phage through mutations in the yqwD2 gene involved in exopolysaccharide biogenesis and export, and the rpoC gene which encodes the RNA polymerase β’ subunit. In response to bacterial resistance, phage EfV12-phi1 evolved varying numbers of 1.8 kb tandem duplications within a putative tail fiber gene. Host range assays indicated that coevolution of this phage-host pair resulted in arms race dynamics in which bacterial resistance and phage infectivity increased over time. Tracking mutations from population sequencing of experimental coevolution can quickly illuminate phage entry points along with resistance strategies in both phage and host – critical information for using phage to manipulate microbial communities.
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Affiliation(s)
- Stephen Wandro
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, United States
| | - Andrew Oliver
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, United States
| | - Tara Gallagher
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, United States
| | - Claudia Weihe
- Department of Ecology and Evolutionary Biology, University of California, Irvine, Irvine, CA, United States
| | - Whitney England
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, United States.,Department of Pharmaceutical Sciences, University of California, Irvine, Irvine, CA, United States
| | - Jennifer B H Martiny
- Department of Ecology and Evolutionary Biology, University of California, Irvine, Irvine, CA, United States
| | - Katrine Whiteson
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, United States
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22
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De Smet J, Hendrix H, Van den Bossche A. Analyzing Phage-Host Protein-Protein Interactions Using Strep-tag ® II Purifications. Methods Mol Biol 2019; 1898:117-136. [PMID: 30570728 DOI: 10.1007/978-1-4939-8940-9_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
After injecting their genome into the bacterial host cell, bacteriophages need to convert the host metabolism toward efficient phage production. For this, specific proteins have evolved which interact with key host proteins to inhibit, activate or redirect the function of these proteins. Since 70% of the currently annotated phage genes are hypothetical proteins of unknown function, the identification and characterization of these phage proteins involved in host-phage protein-protein interactions remains challenging. Here, we describe a method to identify phage proteins involved in host-phage protein-protein interactions using a combination of affinity purifications and mass spectrometry analyses. A bacterial strain is engineered in which a bacterial target protein is fused to a Strep-tag® II at the C-terminal end. This strain is infected with a specific bacteriophage, followed by an affinity purification of the tagged protein which allows the copurification of all bacterial and phage specific interacting proteins. After SDS-PAGE analysis and an in-gel trypsin digestion, the purified interacting proteins are identified by mass spectrometry analysis. The identification of phage proteins involved in interactions provides first hints toward the elucidation of the biological function of these proteins.
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Affiliation(s)
| | - Hanne Hendrix
- Laboratory of Gene Technology, KU Leuven, Leuven, Belgium
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23
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Abstract
T7 development in Escherichia coli requires the inhibition of the housekeeping form of the bacterial RNA polymerase (RNAP), Eσ70, by two T7 proteins: Gp2 and Gp5.7. Although the biological role of Gp2 is well understood, that of Gp5.7 remains to be fully deciphered. Here, we present results from functional and structural analyses to reveal that Gp5.7 primarily serves to inhibit EσS, the predominant form of the RNAP in the stationary phase of growth, which accumulates in exponentially growing E. coli as a consequence of the buildup of guanosine pentaphosphate [(p)ppGpp] during T7 development. We further demonstrate a requirement of Gp5.7 for T7 development in E. coli cells in the stationary phase of growth. Our finding represents a paradigm for how some lytic phages have evolved distinct mechanisms to inhibit the bacterial transcription machinery to facilitate phage development in bacteria in the exponential and stationary phases of growth.
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24
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Yamamoto K, Yamanaka Y, Shimada T, Sarkar P, Yoshida M, Bhardwaj N, Watanabe H, Taira Y, Chatterji D, Ishihama A. Altered Distribution of RNA Polymerase Lacking the Omega Subunit within the Prophages along the Escherichia coli K-12 Genome. mSystems 2018; 3:e00172-17. [PMID: 29468196 PMCID: PMC5811629 DOI: 10.1128/msystems.00172-17] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 01/25/2018] [Indexed: 11/20/2022] Open
Abstract
The RNA polymerase (RNAP) of Escherichia coli K-12 is a complex enzyme consisting of the core enzyme with the subunit structure α2ββ'ω and one of the σ subunits with promoter recognition properties. The smallest subunit, omega (the rpoZ gene product), participates in subunit assembly by supporting the folding of the largest subunit, β', but its functional role remains unsolved except for its involvement in ppGpp binding and stringent response. As an initial approach for elucidation of its functional role, we performed in this study ChIP-chip (chromatin immunoprecipitation with microarray technology) analysis of wild-type and rpoZ-defective mutant strains. The altered distribution of RpoZ-defective RNAP was identified mostly within open reading frames, in particular, of the genes inside prophages. For the genes that exhibited increased or decreased distribution of RpoZ-defective RNAP, the level of transcripts increased or decreased, respectively, as detected by reverse transcription-quantitative PCR (qRT-PCR). In parallel, we analyzed, using genomic SELEX (systemic evolution of ligands by exponential enrichment), the distribution of constitutive promoters that are recognized by RNAP RpoD holoenzyme alone and of general silencer H-NS within prophages. Since all 10 prophages in E. coli K-12 carry only a small number of promoters, the altered occupancy of RpoZ-defective RNAP and of transcripts might represent transcription initiated from as-yet-unidentified host promoters. The genes that exhibited transcription enhanced by RpoZ-defective RNAP are located in the regions of low-level H-NS binding. By using phenotype microarray (PM) assay, alterations of some phenotypes were detected for the rpoZ-deleted mutant, indicating the involvement of RpoZ in regulation of some genes. Possible mechanisms of altered distribution of RNAP inside prophages are discussed. IMPORTANCE The 91-amino-acid-residue small-subunit omega (the rpoZ gene product) of Escherichia coli RNA polymerase plays a structural role in the formation of RNA polymerase (RNAP) as a chaperone in folding the largest subunit (β', of 1,407 residues in length), but except for binding of the stringent signal ppGpp, little is known of its role in the control of RNAP function. After analysis of genomewide distribution of wild-type and RpoZ-defective RNAP by the ChIP-chip method, we found alteration of the RpoZ-defective RNAP inside open reading frames, in particular, of the genes within prophages. For a set of the genes that exhibited altered occupancy of the RpoZ-defective RNAP, transcription was found to be altered as observed by qRT-PCR assay. All the observations here described indicate the involvement of RpoZ in recognition of some of the prophage genes. This study advances understanding of not only the regulatory role of omega subunit in the functions of RNAP but also the regulatory interplay between prophages and the host E. coli for adjustment of cellular physiology to a variety of environments in nature.
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Affiliation(s)
- Kaneyoshi Yamamoto
- Department of Frontier Bioscience, Hosei University, Tokyo, Japan
- Micro-Nano Technology Research Center, Hosei University, Tokyo, Japan
| | - Yuki Yamanaka
- Micro-Nano Technology Research Center, Hosei University, Tokyo, Japan
| | - Tomohiro Shimada
- Micro-Nano Technology Research Center, Hosei University, Tokyo, Japan
- Meiji University, School of Agriculture, Kawasaki, Kanagawa, Japan
| | - Paramita Sarkar
- Department of Frontier Bioscience, Hosei University, Tokyo, Japan
- Indian Institute of Science, Molecular Biophysics Unit, Bangalore, India
| | - Myu Yoshida
- Department of Frontier Bioscience, Hosei University, Tokyo, Japan
| | - Neerupma Bhardwaj
- Indian Institute of Science, Molecular Biophysics Unit, Bangalore, India
| | - Hiroki Watanabe
- Department of Frontier Bioscience, Hosei University, Tokyo, Japan
| | - Yuki Taira
- Department of Frontier Bioscience, Hosei University, Tokyo, Japan
| | - Dipankar Chatterji
- Indian Institute of Science, Molecular Biophysics Unit, Bangalore, India
| | - Akira Ishihama
- Micro-Nano Technology Research Center, Hosei University, Tokyo, Japan
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25
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Tabib-Salazar A, Liu B, Shadrin A, Burchell L, Wang Z, Wang Z, Goren MG, Yosef I, Qimron U, Severinov K, Matthews SJ, Wigneshweraraj S. Full shut-off of Escherichia coli RNA-polymerase by T7 phage requires a small phage-encoded DNA-binding protein. Nucleic Acids Res 2017; 45:7697-7707. [PMID: 28486695 PMCID: PMC5569994 DOI: 10.1093/nar/gkx370] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 04/24/2017] [Indexed: 11/13/2022] Open
Abstract
Infection of Escherichia coli by the T7 phage leads to rapid and selective inhibition of the bacterial RNA polymerase (RNAP) by the 7 kDa T7 protein Gp2. We describe the identification and functional and structural characterisation of a novel 7 kDa T7 protein, Gp5.7, which adopts a winged helix-turn-helix-like structure and specifically represses transcription initiation from host RNAP-dependent promoters on the phage genome via a mechanism that involves interaction with DNA and the bacterial RNAP. Whereas Gp2 is indispensable for T7 growth in E. coli, we show that Gp5.7 is required for optimal infection outcome. Our findings provide novel insights into how phages fine-tune the activity of the host transcription machinery to ensure both successful and efficient phage progeny development.
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Affiliation(s)
- Aline Tabib-Salazar
- MRC Centre for Molecular Microbiology and Infection, Imperial College London, London SW7 2AZ, UK
| | - Bing Liu
- MRC Centre for Molecular Microbiology and Infection, Imperial College London, London SW7 2AZ, UK
| | - Andrey Shadrin
- G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, Moscow 142290, Russia
| | - Lynn Burchell
- MRC Centre for Molecular Microbiology and Infection, Imperial College London, London SW7 2AZ, UK
| | - Zhexin Wang
- MRC Centre for Molecular Microbiology and Infection, Imperial College London, London SW7 2AZ, UK
| | - Zhihao Wang
- MRC Centre for Molecular Microbiology and Infection, Imperial College London, London SW7 2AZ, UK
| | - Moran G Goren
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Ido Yosef
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Udi Qimron
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Konstantin Severinov
- Waksman Institute of Microbiology, Rutgers, The State University of New Jersey, 190 Frelinghuysen Road, Piscataway, NJ 08854-8020, USA
| | - Steve J Matthews
- MRC Centre for Molecular Microbiology and Infection, Imperial College London, London SW7 2AZ, UK
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26
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Brown DR, Sheppard CM, Burchell L, Matthews S, Wigneshweraraj S. The Xp10 Bacteriophage Protein P7 Inhibits Transcription by the Major and Major Variant Forms of the Host RNA Polymerase via a Common Mechanism. J Mol Biol 2016; 428:3911-3919. [PMID: 27515396 PMCID: PMC5053324 DOI: 10.1016/j.jmb.2016.08.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 08/02/2016] [Accepted: 08/03/2016] [Indexed: 01/24/2023]
Abstract
The σ factor is a functionally obligatory subunit of the bacterial transcription machinery, the RNA polymerase. Bacteriophage-encoded small proteins that either modulate or inhibit the bacterial RNAP to allow the temporal regulation of bacteriophage gene expression often target the activity of the major bacterial σ factor, σ70. Previously, we showed that during Xanthomonas oryzae phage Xp10 infection, the phage protein P7 inhibits the host RNAP by preventing the productive engagement with the promoter and simultaneously displaces the σ70 factor from the RNAP. In this study, we demonstrate that P7 also inhibits the productive engagement of the bacterial RNAP containing the major variant bacterial σ factor, σ54, with its cognate promoter. The results suggest for the first time that the major variant form of the host RNAP can also be targeted by bacteriophage-encoded transcription regulatory proteins. Since the major and major variant σ factor interacting surfaces in the RNAP substantially overlap, but different regions of σ70 and σ54 are used for binding to the RNAP, our results further underscore the importance of the σ–RNAP interface in bacterial RNAP function and regulation and potentially for intervention by antibacterials. Xp10 phage transcription regulator P7 inhibits transcription by RNAP containing σ54. P7 prevents the productive engagement of the σ54–RNAP with the promoter DNA. • P7 disrupts preformed σ54–RNAP-promoter complexes.
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Affiliation(s)
- D R Brown
- MRC Centre for Molecular Microbiology and Infection, Imperial College London, SW7 2AZ, UK.
| | - C M Sheppard
- MRC Centre for Molecular Microbiology and Infection, Imperial College London, SW7 2AZ, UK
| | - L Burchell
- MRC Centre for Molecular Microbiology and Infection, Imperial College London, SW7 2AZ, UK
| | - S Matthews
- MRC Centre for Molecular Microbiology and Infection, Imperial College London, SW7 2AZ, UK
| | - S Wigneshweraraj
- MRC Centre for Molecular Microbiology and Infection, Imperial College London, SW7 2AZ, UK.
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Global Transcriptomic Analysis of Interactions between Pseudomonas aeruginosa and Bacteriophage PaP3. Sci Rep 2016; 6:19237. [PMID: 26750429 PMCID: PMC4707531 DOI: 10.1038/srep19237] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 12/07/2015] [Indexed: 02/06/2023] Open
Abstract
The interactions between Bacteriophage (phage) and host bacteria are widespread in nature and influences of phage replication on the host cells are complex and extensive. Here, we investigate genome-wide interactions of Pseudomonas aeruginosa (P. aeruginosa) and its temperate phage PaP3 at five time points during phage infection. Compared to the uninfected host, 38% (2160/5633) genes of phage-infected host were identified as differentially expressed genes (DEGs). Functional analysis of the repressed DEGs revealed infection-stage-dependent pathway communications. Based on gene co-expression analysis, most PaP3 middle genes were predicted to have negative impact on host transcriptional regulators. Sub-network enrichment analysis revealed that adjacent genes of PaP3 interacted with the same host genes and might possess similar functions. Finally, our results suggested that during the whole infection stage, the early genes of PaP3 had stronger regulatory role in host gene expression than middle and late genes, while the host genes involved amino acid metabolism were the most “vulnerable” targets of these phage genes. This work provides the basis for understanding survival mechanisms of parasites and host, and seeking phage gene products that could potentially be used in anti-bacterial infection.
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Yakunina M, Artamonova T, Borukhov S, Makarova KS, Severinov K, Minakhin L. A non-canonical multisubunit RNA polymerase encoded by a giant bacteriophage. Nucleic Acids Res 2015; 43:10411-20. [PMID: 26490960 PMCID: PMC4666361 DOI: 10.1093/nar/gkv1095] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 10/10/2015] [Indexed: 11/21/2022] Open
Abstract
The infection of Pseudomonas aeruginosa by the giant bacteriophage phiKZ is resistant to host RNA polymerase (RNAP) inhibitor rifampicin. phiKZ encodes two sets of polypeptides that are distantly related to fragments of the two largest subunits of cellular multisubunit RNAPs. Polypeptides of one set are encoded by middle phage genes and are found in the phiKZ virions. Polypeptides of the second set are encoded by early phage genes and are absent from virions. Here, we report isolation of a five-subunit RNAP from phiKZ-infected cells. Four subunits of this enzyme are cellular RNAP subunits homologs of the non-virion set; the fifth subunit is a protein of unknown function. In vitro, this complex initiates transcription from late phiKZ promoters in rifampicin-resistant manner. Thus, this enzyme is a non-virion phiKZ RNAP responsible for transcription of late phage genes. The phiKZ RNAP lacks identifiable assembly and promoter specificity subunits/factors characteristic for eukaryal, archaeal and bacterial RNAPs and thus provides a unique model for comparative analysis of the mechanism, regulation and evolution of this important class of enzymes.
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Affiliation(s)
- Maria Yakunina
- Peter the Great St. Petersburg Polytechnic University, St. Petersburg, 195251, Russia Department of Molecular Biology and Biochemistry, Waksman Institute, Rutgers, The State University of New Jersey, Piscataway, NJ 08854-8020, USA
| | - Tatyana Artamonova
- Peter the Great St. Petersburg Polytechnic University, St. Petersburg, 195251, Russia
| | - Sergei Borukhov
- Peter the Great St. Petersburg Polytechnic University, St. Petersburg, 195251, Russia Rowan University School of Osteopathic Medicine, Stratford, NJ 08084-1501, USA
| | - Kira S Makarova
- National Center for Biotechnology Information NLM, National Institutes of Health Bethesda, MD 20894, USA
| | - Konstantin Severinov
- Peter the Great St. Petersburg Polytechnic University, St. Petersburg, 195251, Russia Department of Molecular Biology and Biochemistry, Waksman Institute, Rutgers, The State University of New Jersey, Piscataway, NJ 08854-8020, USA Skolkovo Institute of Science and Technology, Skolkovo, 143026, Russia
| | - Leonid Minakhin
- Peter the Great St. Petersburg Polytechnic University, St. Petersburg, 195251, Russia Department of Molecular Biology and Biochemistry, Waksman Institute, Rutgers, The State University of New Jersey, Piscataway, NJ 08854-8020, USA
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29
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Van den Bossche A, Ceyssens PJ, De Smet J, Hendrix H, Bellon H, Leimer N, Wagemans J, Delattre AS, Cenens W, Aertsen A, Landuyt B, Minakhin L, Severinov K, Noben JP, Lavigne R. Systematic identification of hypothetical bacteriophage proteins targeting key protein complexes of Pseudomonas aeruginosa. J Proteome Res 2014; 13:4446-56. [PMID: 25185497 DOI: 10.1021/pr500796n] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Addressing the functionality of predicted genes remains an enormous challenge in the postgenomic era. A prime example of genes lacking functional assignments are the poorly conserved, early expressed genes of lytic bacteriophages, whose products are involved in the subversion of the host metabolism. In this study, we focused on the composition of important macromolecular complexes of Pseudomonas aeruginosa involved in transcription, DNA replication, fatty acid biosynthesis, RNA regulation, energy metabolism, and cell division during infection with members of seven distinct clades of lytic phages. Using affinity purifications of these host protein complexes coupled to mass spectrometric analyses, 37 host complex-associated phage proteins could be identified. Importantly, eight of these show an inhibitory effect on bacterial growth upon episomal expression, suggesting that these phage proteins are potentially involved in hijacking the host complexes. Using complementary protein-protein interaction assays, we further mapped the inhibitory interaction of gp12 of phage 14-1 to the α subunit of the RNA polymerase. Together, our data demonstrate the powerful use of interactomics to unravel the biological role of hypothetical phage proteins, which constitute an enormous untapped source of novel antibacterial proteins. (Data are available via ProteomeXchange with identifier PXD001199.).
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30
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Development of giant bacteriophage ϕKZ is independent of the host transcription apparatus. J Virol 2014; 88:10501-10. [PMID: 24965474 DOI: 10.1128/jvi.01347-14] [Citation(s) in RCA: 111] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Pseudomonas aeruginosa bacteriophage ϕKZ is the type representative of the giant phage genus, which is characterized by unusually large virions and genomes. By unraveling the transcriptional map of the ∼ 280-kb ϕKZ genome to single-nucleotide resolution, we combine 369 ϕKZ genes into 134 operons. Early transcription is initiated from highly conserved AT-rich promoters distributed across the ϕKZ genome and located on the same strand of the genome. Early transcription does not require phage or host protein synthesis. Transcription of middle and late genes is dependent on protein synthesis and mediated by poorly conserved middle and late promoters. Unique to ϕKZ is its ability to complete its infection in the absence of bacterial RNA polymerase (RNAP) enzyme activity. We propose that transcription of the ϕKZ genome is performed by the consecutive action of two ϕKZ-encoded, noncanonical multisubunit RNAPs, one of which is packed within the virion, another being the product of early genes. This unique, rifampin-resistant transcriptional machinery is conserved within the diverse giant phage genus. IMPORTANCE The data presented in this paper offer, for the first time, insight into the complex transcriptional scheme of giant bacteriophages. We show that Pseudomonas aeruginosa giant phage ϕKZ is able to infect and lyse its host cell and produce phage progeny in the absence of functional bacterial transcriptional machinery. This unique property can be attributed to two phage-encoded putative RNAP enzymes, which contain very distant homologues of bacterial β and β'-like RNAP subunits.
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31
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Tagami S, Sekine SI, Minakhin L, Esyunina D, Akasaka R, Shirouzu M, Kulbachinskiy A, Severinov K, Yokoyama S. Structural basis for promoter specificity switching of RNA polymerase by a phage factor. Genes Dev 2014; 28:521-31. [PMID: 24589779 PMCID: PMC3950348 DOI: 10.1101/gad.233916.113] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Transcription of DNA to RNA by DNA-dependent RNA polymerase (RNAP) is the first step of gene expression and a major regulation point. Bacteriophages hijack their host's transcription machinery and direct it to serve their needs. The gp39 protein encoded by Thermus thermophilus phage P23-45 binds the host's RNAP and inhibits transcription initiation from its major "-10/-35" class promoters. Phage promoters belonging to the minor "extended -10" class are minimally inhibited. We report the crystal structure of the T. thermophilus RNAP holoenzyme complexed with gp39, which explains the mechanism for RNAP promoter specificity switching. gp39 simultaneously binds to the RNAP β-flap domain and the C-terminal domain of the σ subunit (region 4 of the σ subunit [σ4]), thus relocating the β-flap tip and σ4. The ~45 Å displacement of σ4 is incompatible with its binding to the -35 promoter consensus element, thus accounting for the inhibition of transcription from -10/-35 class promoters. In contrast, this conformational change is compatible with the recognition of extended -10 class promoters. These results provide the structural bases for the conformational modulation of the host's RNAP promoter specificity to switch gene expression toward supporting phage development for gp39 and, potentially, other phage proteins, such as T4 AsiA.
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Affiliation(s)
- Shunsuke Tagami
- RIKEN Systems and Structural Biology Center, Tsurumi-ku, Yokohama 230-0045, Japan
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32
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Liu B, Shadrin A, Sheppard C, Mekler V, Xu Y, Severinov K, Matthews S, Wigneshweraraj S. The sabotage of the bacterial transcription machinery by a small bacteriophage protein. BACTERIOPHAGE 2014; 4:e28520. [PMID: 24701369 DOI: 10.4161/bact.28520] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 03/11/2014] [Accepted: 03/12/2014] [Indexed: 11/19/2022]
Abstract
Many bacteriophages produce small proteins that specifically interfere with the bacterial host transcription machinery and thus contribute to the acquisition of the bacterial cell by the bacteriophage. We recently described how a small protein, called P7, produced by the Xp10 bacteriophage inhibits bacterial transcription initiation by causing the dissociation of the promoter specificity sigma factor subunit from the host RNA polymerase holoenzyme. In this addendum to the original publication, we present the highlights of that research.
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Affiliation(s)
- Bing Liu
- MRC Centre for Molecular Bacteriology and Infection; Imperial College London; London, UK
| | - Andrey Shadrin
- MRC Centre for Molecular Bacteriology and Infection; Imperial College London; London, UK
| | - Carol Sheppard
- MRC Centre for Molecular Bacteriology and Infection; Imperial College London; London, UK
| | - Vladimir Mekler
- Waksman Institute for Microbiology and Department of Molecular Biology and Biochemistry; Rutgers, The State University of New Jersey; Piscataway, NJ USA
| | - Yingqi Xu
- MRC Centre for Molecular Bacteriology and Infection; Imperial College London; London, UK
| | - Konstantin Severinov
- Waksman Institute for Microbiology and Department of Molecular Biology and Biochemistry; Rutgers, The State University of New Jersey; Piscataway, NJ USA ; St. Petersburg State Polytechnical University; St. Petersburg, Russia
| | - Steve Matthews
- MRC Centre for Molecular Bacteriology and Infection; Imperial College London; London, UK
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33
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Liu B, Shadrin A, Sheppard C, Mekler V, Xu Y, Severinov K, Matthews S, Wigneshweraraj S. A bacteriophage transcription regulator inhibits bacterial transcription initiation by σ-factor displacement. Nucleic Acids Res 2014; 42:4294-305. [PMID: 24482445 PMCID: PMC3985653 DOI: 10.1093/nar/gku080] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Bacteriophages (phages) appropriate essential processes of bacterial hosts to benefit their own development. The multisubunit bacterial RNA polymerase (RNAp) enzyme, which catalyses DNA transcription, is targeted by phage-encoded transcription regulators that selectively modulate its activity. Here, we describe the structural and mechanistic basis for the inhibition of bacterial RNAp by the transcription regulator P7 encoded by Xanthomonas oryzae phage Xp10. We reveal that P7 uses a two-step mechanism to simultaneously interact with the catalytic β and β' subunits of the bacterial RNAp and inhibits transcription initiation by inducing the displacement of the σ(70)-factor on initial engagement of RNAp with promoter DNA. The new mode of interaction with and inhibition mechanism of bacterial RNAp by P7 underscore the remarkable variety of mechanisms evolved by phages to interfere with host transcription.
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Affiliation(s)
- Bing Liu
- MRC Centre for Molecular Microbiology and Infection, Imperial College London, London SW7 2AZ, UK, Waksman Institute for Microbiology and Department of Molecular Biology and Biochemistry, Rutgers, The State University of New Jersey, Piscataway, NJ USA and St. Petersburg State Polytechnical University, St. Petersburg, Russia
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34
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Sheppard C, James E, Barton G, Matthews S, Severinov K, Wigneshweraraj S. A non-bacterial transcription factor inhibits bacterial transcription by a multipronged mechanism. RNA Biol 2013; 10:495-501. [PMID: 23558648 DOI: 10.4161/rna.24283] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The process of transcription initiation is the major target for regulation of gene expression in bacteria and is performed by a multi-subunit RNA polymerase enzyme (RNAp). A complex network of regulatory elements controls the activity of the RNAp to fine-tune transcriptional output. Thus, RNAp is a nexus for controlling bacterial gene expression at the transcription level. Many bacteriophages, viruses that infect bacteria, encode transcription factors that specifically target and modulate the activity of the host RNAp and, thereby, facilitate the acquisition of the host bacteria by the phage. Here, we describe the modus operandi of a T7 bacteriophage-encoded small protein called Gp2 and define Gp2 as a non-bacterial regulator of bacterial transcription.
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Affiliation(s)
- Carol Sheppard
- MRC Centre for Molecular Bacteriology and Infection, Faculty of Medicine, Imperial College London, London, UK
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35
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Abstract
Phage G1 gp67 is a 23 kDa protein that binds to the Staphylococcus aureus (Sau) RNA polymerase (RNAP) σ(A) subunit and blocks cell growth by inhibiting transcription. We show that gp67 has little to no effect on transcription from most promoters but is a potent inhibitor of ribosomal RNA transcription. A 2.0-Å-resolution crystal structure of the complex between gp67 and Sau σ(A) domain 4 (σ(A)(4)) explains how gp67 joins the RNAP promoter complex through σ(A)(4) without significantly affecting σ(A)(4) function. Our results indicate that gp67 forms a complex with RNAP at most, if not all, σ(A)-dependent promoters, but selectively inhibits promoters that depend on an interaction between upstream DNA and the RNAP α-subunit C-terminal domain (αCTD). Thus, we reveal a promoter-specific transcription inhibition mechanism by which gp67 interacts with the RNAP promoter complex through one subunit (σ(A)), and selectively affects the function of another subunit (αCTD) depending on promoter usage.
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36
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Drulis-Kawa Z, Majkowska-Skrobek G, Maciejewska B, Delattre AS, Lavigne R. Learning from bacteriophages - advantages and limitations of phage and phage-encoded protein applications. Curr Protein Pept Sci 2012; 13:699-722. [PMID: 23305359 PMCID: PMC3594737 DOI: 10.2174/138920312804871193] [Citation(s) in RCA: 161] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 07/12/2012] [Accepted: 09/20/2012] [Indexed: 12/18/2022]
Abstract
The emergence of bacteria resistance to most of the currently available antibiotics has become a critical therapeutic problem. The bacteria causing both hospital and community-acquired infections are most often multidrug resistant. In view of the alarming level of antibiotic resistance between bacterial species and difficulties with treatment, alternative or supportive antibacterial cure has to be developed. The presented review focuses on the major characteristics of bacteriophages and phage-encoded proteins affecting their usefulness as antimicrobial agents. We discuss several issues such as mode of action, pharmacodynamics, pharmacokinetics, resistance and manufacturing aspects of bacteriophages and phage-encoded proteins application.
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Affiliation(s)
- Zuzanna Drulis-Kawa
- Institute of Genetics and Microbiology, University of Wroclaw, Przybyszewskiego 63/77, 51-148 Wroclaw, Poland.
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37
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Shadrin A, Sheppard C, Severinov K, Matthews S, Wigneshweraraj S. Substitutions in the Escherichia coli RNA polymerase inhibitor T7 Gp2 that allow inhibition of transcription when the primary interaction interface between Gp2 and RNA polymerase becomes compromised. MICROBIOLOGY-SGM 2012; 158:2753-2764. [PMID: 22977089 PMCID: PMC3541766 DOI: 10.1099/mic.0.062547-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The Escherichia coli-infecting bacteriophage T7 encodes a 7 kDa protein, called Gp2, which is a potent inhibitor of the host RNA polymerase (RNAp). Gp2 is essential for T7 phage development. The interaction site for Gp2 on the E. coli RNAp is the β′ jaw domain, which is part of the DNA binding channel. The binding of Gp2 to the β′ jaw antagonizes several steps associated with interactions between the RNAp and promoter DNA, leading to inhibition of transcription at the open promoter complex formation step. In the structure of the complex formed between Gp2 and a fragment of the β′ jaw, amino acid residues in the β3 strand of Gp2 contribute to the primary interaction interface with the β′ jaw. The 7009 E. coli strain is resistant to T7 because it carries a charge reversal point mutation in the β′ jaw that prevents Gp2 binding. However, a T7 phage encoding a mutant form of Gp2, called Gp2β, which carries triple amino acid substitutions E24K, F27Y and R56C, can productively infect this strain. By studying the molecular basis of inhibition of RNAp from the 7009 strain by Gp2β, we provide several lines of evidence that the E24K and F27Y substitutions facilitate an interaction with RNAp when the primary interaction interface with the β′ jaw is compromised. The proposed additional interaction interface between RNAp and Gp2 may contribute to the multipronged mechanism of transcription inhibition by Gp2.
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Affiliation(s)
- Andrey Shadrin
- Section of Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, UK
| | - Carol Sheppard
- Section of Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, UK
| | - Konstantin Severinov
- Institute of Gene Biology, Russian Academy of Sciences, Moscow 119334, Russia.,Institute of Molecular Genetics, Russian Academy of Sciences, Moscow 123182, Russia.,Waksman Institute for Microbiology and Department of Molecular Biology and Biochemistry, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
| | - Steve Matthews
- Section of Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, UK
| | - Sivaramesh Wigneshweraraj
- Section of Microbiology and MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, UK
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38
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James E, Liu M, Sheppard C, Mekler V, Cámara B, Liu B, Simpson P, Cota E, Severinov K, Matthews S, Wigneshweraraj S. Structural and mechanistic basis for the inhibition of Escherichia coli RNA polymerase by T7 Gp2. Mol Cell 2012; 47:755-66. [PMID: 22819324 PMCID: PMC3778932 DOI: 10.1016/j.molcel.2012.06.013] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Revised: 01/04/2012] [Accepted: 06/12/2012] [Indexed: 11/27/2022]
Abstract
The T7 phage-encoded small protein Gp2 is a non-DNA-binding transcription factor that interacts with the jaw domain of the Escherichia coli (Ec) RNA polymerase (RNAp) β′ subunit and inhibits transcriptionally proficient promoter-complex (RPo) formation. Here, we describe the high-resolution solution structure of the Gp2-Ec β′ jaw domain complex and show that Gp2 and DNA compete for binding to the β′ jaw domain. We reveal that efficient inhibition of RPo formation by Gp2 requires the amino-terminal σ70 domain region 1.1 (R1.1), and that Gp2 antagonizes the obligatory movement of R1.1 during RPo formation. We demonstrate that Gp2 inhibits RPo formation not just by steric occlusion of the RNAp-DNA interaction but also through long-range antagonistic effects on RNAp-promoter interactions around the RNAp active center that likely occur due to repositioning of R1.1 by Gp2. The inhibition of Ec RNAp by Gp2 thus defines a previously uncharacterized mechanism by which bacterial transcription is regulated by a viral factor.
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Affiliation(s)
- Ellen James
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, UK
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39
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Sheppard C, Cámara B, Shadrin A, Akulenko N, Liu M, Baldwin G, Severinov K, Cota E, Matthews S, Wigneshweraraj SR. Reprint of: Inhibition of Escherichia coli RNAp by T7 Gp2 protein: Role of Negatively Charged Strip of Amino Acid Residues in Gp2. J Mol Biol 2011; 412:832-41. [DOI: 10.1016/j.jmb.2011.07.064] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Revised: 02/03/2011] [Accepted: 02/04/2011] [Indexed: 11/15/2022]
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40
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Mekler V, Minakhin L, Sheppard C, Wigneshweraraj S, Severinov K. Molecular mechanism of transcription inhibition by phage T7 gp2 protein. J Mol Biol 2011; 413:1016-27. [PMID: 21963987 DOI: 10.1016/j.jmb.2011.09.029] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2011] [Revised: 09/14/2011] [Accepted: 09/15/2011] [Indexed: 11/17/2022]
Abstract
Escherichia coli T7 bacteriophage gp2 protein is a potent inhibitor of host RNA polymerase (RNAP). gp2 inhibits formation of open promoter complex by binding to the β' jaw, an RNAP domain that interacts with downstream promoter DNA. Here, we used an engineered promoter with an optimized sequence to obtain and characterize a specific promoter complex containing RNAP and gp2. In this complex, localized melting of promoter DNA is initiated but does not propagate to include the point of the transcription start. As a result, the complex is transcriptionally inactive. Using a highly sensitive RNAP beacon assay, we performed quantitative real-time measurements of specific binding of the RNAP-gp2 complex to promoter DNA and various promoter fragments. In this way, the effect of gp2 on RNAP interaction with promoters was dissected. As expected, gp2 greatly decreased RNAP affinity to downstream promoter duplex. However, gp2 also inhibited RNAP binding to promoter fragments that lacked downstream promoter DNA that interacts with the β' jaw. The inhibition was caused by gp2-mediated decrease of the RNAP binding affinity to template and non-template strand segments of the transcription bubble downstream of the -10 promoter element. The inhibition of RNAP interactions with single-stranded segments of the transcription bubble by gp2 is a novel effect, which may occur via allosteric mechanism that is set in motion by the gp2 binding to the β' jaw.
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Affiliation(s)
- Vladimir Mekler
- Department of Molecular Biology and Biochemistry, Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA.
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41
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Sheppard C, Cámara B, Shadrin A, Akulenko N, Liu M, Baldwin G, Severinov K, Cota E, Matthews S, Wigneshweraraj SR. Inhibition of Escherichia coli RNAp by T7 Gp2 protein: role of negatively charged strip of amino acid residues in Gp2. J Mol Biol 2011; 407:623-32. [PMID: 21316373 DOI: 10.1016/j.jmb.2011.02.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Revised: 02/03/2011] [Accepted: 02/04/2011] [Indexed: 11/29/2022]
Abstract
Gp2, a 7 kDa protein encoded by T7 bacteriophage, is a potent inhibitor of Escherichia coli RNA polymerase (RNAp), the enzyme responsible for transcription of all bacterial genes and early viral genes. A prominent feature in the structure of Gp2 is a contiguous strip of seven negatively charged amino acid residues (negatively charged strip or NCS), located along one side of the molecule. The role of the NCS in Gp2 function is not known. Here, the in vivo and in vitro properties of altered forms of Gp2 with amino acid substitutions in the NCS are described. While mutations in the NCS do not compromise the folding or the ability of Gp2 to bind to the RNAp β' subunit, disruption of the NCS significantly attenuates Gp2 function in vivo and its ability to inhibit RNAp in vitro. Efficient inhibition of the RNAp by Gp2 also involves the amino terminal region 1 domain of the RNAp promoter specificity subunit σ(70), located in the vicinity of the primary Gp2 binding site in β'. The results are discussed in the context of hypothetical molecular mechanisms of RNAp inhibition by Gp2.
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Affiliation(s)
- Carol Sheppard
- Section of Microbiology, Faculty of Medicine & Centre for Molecular Microbiology and Infection, Imperial College London, SW7 2AZ, UK
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Berdygulova Z, Westblade LF, Florens L, Koonin EV, Chait BT, Ramanculov E, Washburn MP, Darst SA, Severinov K, Minakhin L. Temporal regulation of gene expression of the Thermus thermophilus bacteriophage P23-45. J Mol Biol 2010; 405:125-42. [PMID: 21050864 DOI: 10.1016/j.jmb.2010.10.049] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Revised: 10/25/2010] [Accepted: 10/27/2010] [Indexed: 11/30/2022]
Abstract
Regulation of gene expression during infection of the thermophilic bacterium Thermus thermophilus HB8 with the bacteriophage P23-45 was investigated. Macroarray analysis revealed host transcription shut-off and identified three temporal classes of phage genes; early, middle and late. Primer extension experiments revealed that the 5' ends of P23-45 early transcripts are preceded by a common sequence motif that likely defines early viral promoters. T. thermophilus HB8 RNA polymerase (RNAP) recognizes middle and late phage promoters in vitro but does not recognize early promoters. In vivo experiments revealed the presence of rifampicin-resistant RNA polymerizing activity in infected cells responsible for early transcription. The product of the P23-45 early gene 64 shows a distant sequence similarity with the largest, catalytic subunits of multisubunit RNAPs and contains the conserved metal-binding motif that is diagnostic of these proteins. We hypothesize that ORF64 encodes rifampicin-resistant phage RNAP that recognizes early phage promoters. Affinity isolation of T. thermophilus HB8 RNAP from P23-45-infected cells identified two phage-encoded proteins, gp39 and gp76, that bind the host RNAP and inhibit in vitro transcription from host promoters, but not from middle or late phage promoters, and may thus control the shift from host to viral gene expression during infection. To our knowledge, gp39 and gp76 are the first characterized bacterial RNAP-binding proteins encoded by a thermophilic phage.
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Abstract
Gene transcription is a fundamental cellular process carried out by RNA polymerase (RNAP) enzymes and is highly regulated through the action of gene regulatory complexes. Important mechanistic insights have been gained from structural studies on multisubunit RNAP from bacteria, yeast and archaea, although the initiation process that involves the conversion of the inactive transcription complex to an active one has yet to be fully understood. RNAPs are unambiguously closely related in structure and function across all kingdoms of life and have conserved mechanisms. In bacteria, sigma (sigma) factors direct RNAP to specific promoter sites and the RNAP/sigma holoenzyme can either form a stable closed complex that is incompetent for transcription (as in the case of sigma(54)) or can spontaneously proceed to an open complex that is competent for transcription (as in the case of sigma(70)). The conversion of the RNAP/sigma(54) closed complex to an open complex requires ATP hydrolysis by enhancer-binding proteins, hence providing an ideal model system for studying the initiation process biochemically and structurally. In this review, we present recent structural studies of the two major bacterial RNAP holoenzymes and focus on mechanistic advances in the transcription initiation process via enhancer-binding proteins.
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Affiliation(s)
- Tamaswati Ghosh
- Department of Life Sciences, Centre for Structural Biology, Division of Molecular Biosciences, Imperial College London, London, UK
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44
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T7 phage protein Gp2 inhibits the Escherichia coli RNA polymerase by antagonizing stable DNA strand separation near the transcription start site. Proc Natl Acad Sci U S A 2010; 107:2247-52. [PMID: 20133868 DOI: 10.1073/pnas.0907908107] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Infection of Escherichia coli by the T7 phage leads to rapid and selective inhibition of the host RNA polymerase (RNAP)--a multi-subunit enzyme responsible for gene transcription--by a small ( approximately 7 kDa) phage-encoded protein called Gp2. Gp2 is also a potent inhibitor of E. coli RNAP in vitro. Here we describe the first atomic resolution structure of Gp2, which reveals a distinct run of surface-exposed negatively charged amino acid residues on one side of the molecule. Our comprehensive mutagenesis data reveal that two conserved arginine residues located on the opposite side of Gp2 are important for binding to and inhibition of RNAP. Based on a structural model of the Gp2-RNAP complex, we propose that inhibition of transcription by Gp2 involves prevention of RNAP-promoter DNA interactions required for stable DNA strand separation and maintenance of the "transcription bubble" near the transcription start site, an obligatory step in the formation of a transcriptionally competent promoter complex.
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45
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A two-subunit bacterial sigma-factor activates transcription in Bacillus subtilis. Proc Natl Acad Sci U S A 2009; 106:21323-8. [PMID: 19940246 DOI: 10.1073/pnas.0910006106] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The sigma-like factor YvrI and coregulator YvrHa activate transcription from a small set of conserved promoters in Bacillus subtilis. We report here that these two proteins independently contribute sigma-region 2 and sigma-region 4 functions to a holoenzyme-promoter DNA complex. YvrI binds RNA polymerase (RNAP) through a region 4 interaction with the beta-subunit flap domain and mediates specific promoter recognition but cannot initiate DNA melting at the -10 promoter element. Conversely, YvrHa possesses sequence similarity to a conserved core-binding motif in sigma-region 2 and binds to the N-terminal coiled-coil element in the RNAP beta'-subunit previously implicated in interaction with region 2 of sigma-factors. YvrHa plays an essential role in stabilizing the open complex and interacts specifically with the N-terminus of YvrI. Based on these results, we propose that YvrHa is situated in the transcription complex proximal to the -10 element of the promoter, whereas YvrI is responsible for -35 region recognition. This system presents an unusual example of a two-subunit bacterial sigma-factor.
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46
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Stewart CR, Yip TK, Myles B, Laughlin L. Roles of genes 38, 39, and 40 in shutoff of host biosyntheses during infection of Bacillus subtilis by bacteriophage SPO1. Virology 2009; 392:271-4. [DOI: 10.1016/j.virol.2009.06.046] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2009] [Revised: 06/22/2009] [Accepted: 06/26/2009] [Indexed: 10/20/2022]
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47
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Busby S, Kolb A, Buc H. Where it all Begins: An Overview of Promoter Recognition and Open Complex Formation. RNA POLYMERASES AS MOLECULAR MOTORS 2009. [DOI: 10.1039/9781847559982-00013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Stephen Busby
- School of Biosciences, University of Birmingham Birmingham B15 2TT United Kingdom
| | - Annie Kolb
- Institut Pasteur, Molecular Genetics Unit and CNRS URA 2172 25 rue du Dr. Roux 75724 Paris Cedex 15 France
| | - Henri Buc
- CIS Institut Pasteur75724Paris Cedex 15France
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48
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Lavigne R, Villegas A, Kropinksi AM. In silico characterization of DNA motifs with particular reference to promoters and terminators. Methods Mol Biol 2009; 502:113-129. [PMID: 19082554 DOI: 10.1007/978-1-60327-565-1_8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Knowledge of the regulatory elements contained within bacteriophage genomes forms the basis for understanding genomic expression and organization. The in silico prediction of promoter and terminator sequences in phage genomes is a first step towards this understanding. In this chapter, a number of programs and resources to identify regulatory elements are listed and discussed. Combining the available web-resources and literature data optimizes these predictions and can thus aid in a more directed experimental identification of these regulatory elements.
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Affiliation(s)
- Rob Lavigne
- Department of Biosystems, Division of Gene Technology, Katholieke Universiteit Leuven, Leuven, Belgium
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49
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Nechaev S, Severinov K. The elusive object of desire--interactions of bacteriophages and their hosts. Curr Opin Microbiol 2008; 11:186-93. [PMID: 18400552 DOI: 10.1016/j.mib.2008.02.009] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2008] [Revised: 02/18/2008] [Accepted: 02/21/2008] [Indexed: 12/27/2022]
Abstract
Bacteria and their viruses (phages) are locked in an evolutionary contest, with each side producing constantly changing mechanisms of attack and defense that are aimed to increase the odds of survival. As a result, phages play central roles in a great variety of genetic processes and increase the rate of evolutionary change of the bacterial host, which could ultimately work to the benefit of the host in a long run.
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Affiliation(s)
- Sergei Nechaev
- Laboratory of Molecular Carcinogenesis, NIEHS/NIH, Room D434, 111 Alexander Dr, Research Triangle Park, NC 27709, USA.
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50
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Campbell EA, Westblade LF, Darst SA. Regulation of bacterial RNA polymerase sigma factor activity: a structural perspective. Curr Opin Microbiol 2008; 11:121-7. [PMID: 18375176 DOI: 10.1016/j.mib.2008.02.016] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2008] [Revised: 02/14/2008] [Accepted: 02/21/2008] [Indexed: 12/16/2022]
Abstract
In bacteria, sigma factors are essential for the promoter DNA-binding specificity of RNA polymerase. The sigma factors themselves are regulated by anti-sigma factors that bind and inhibit their cognate sigma factor, and 'appropriators' that deploy a particular sigma-associated RNA polymerase to a specific promoter class. Adding to the complexity is the regulation of anti-sigma factors by both anti-anti-sigma factors, which turn on sigma factor activity, and co-anti-sigma factors that act in concert with their partner anti-sigma factor to inhibit or redirect sigma activity. While sigma factor structure and function are highly conserved, recent results highlight the diversity of structures and mechanisms that bacteria use to regulate sigma factor activity, reflecting the diversity of environmental cues that the bacterial transcription system has evolved to respond.
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Affiliation(s)
- Elizabeth A Campbell
- Laboratory of Molecular Biophysics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA.
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