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Giermasińska-Buczek K, Gawor J, Stefańczyk E, Gągała U, Żuchniewicz K, Rekosz-Burlaga H, Gromadka R, Łobocka M. Interaction of bacteriophage P1 with an epiphytic Pantoea agglomerans strain-the role of the interplay between various mobilome elements. Front Microbiol 2024; 15:1356206. [PMID: 38591037 PMCID: PMC10999674 DOI: 10.3389/fmicb.2024.1356206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 02/21/2024] [Indexed: 04/10/2024] Open
Abstract
P1 is a model, temperate bacteriophage of the 94 kb genome. It can lysogenize representatives of the Enterobacterales order. In lysogens, it is maintained as a plasmid. We tested P1 interactions with the biocontrol P. agglomerans L15 strain to explore the utility of P1 in P. agglomerans genome engineering. A P1 derivative carrying the Tn9 (cmR) transposon could transfer a plasmid from Escherichia coli to the L15 cells. The L15 cells infected with this derivative formed chloramphenicol-resistant colonies. They could grow in a liquid medium with chloramphenicol after adaptation and did not contain prophage P1 but the chromosomally inserted cmR marker of P1 Tn9 (cat). The insertions were accompanied by various rearrangements upstream of the Tn9 cat gene promoter and the loss of IS1 (IS1L) from the corresponding region. Sequence analysis of the L15 strain genome revealed a chromosome and three plasmids of 0.58, 0.18, and 0.07 Mb. The largest and the smallest plasmid appeared to encode partition and replication incompatibility determinants similar to those of prophage P1, respectively. In the L15 derivatives cured of the largest plasmid, P1 with Tn9 could not replace the smallest plasmid even if selected. However, it could replace the smallest and the largest plasmid of L15 if its Tn9 IS1L sequence driving the Tn9 mobility was inactivated or if it was enriched with an immobile kanamycin resistance marker. Moreover, it could develop lytically in the L15 derivatives cured of both these plasmids. Clearly, under conditions of selection for P1, the mobility of the P1 selective marker determines whether or not the incoming P1 can outcompete the incompatible L15 resident plasmids. Our results demonstrate that P. agglomerans can serve as a host for bacteriophage P1 and can be engineered with the help of this phage. They also provide an example of how antibiotics can modify the outcome of horizontal gene transfer in natural environments. Numerous plasmids of Pantoea strains appear to contain determinants of replication or partition incompatibility with P1. Therefore, P1 with an immobile selective marker may be a tool of choice in curing these strains from the respective plasmids to facilitate their functional analysis.
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Affiliation(s)
- Katarzyna Giermasińska-Buczek
- Department of Biochemistry and Microbiology, Institute of Biology, Warsaw University of Life Sciences (SGGW-WULS), Warsaw, Poland
- Institute of Biochemistry and Biophysics of the Polish Academy of Sciences, Warsaw, Poland
| | - Jan Gawor
- Institute of Biochemistry and Biophysics of the Polish Academy of Sciences, Warsaw, Poland
| | - Emil Stefańczyk
- Institute of Biochemistry and Biophysics of the Polish Academy of Sciences, Warsaw, Poland
| | - Urszula Gągała
- Department of Biochemistry and Microbiology, Institute of Biology, Warsaw University of Life Sciences (SGGW-WULS), Warsaw, Poland
| | - Karolina Żuchniewicz
- Institute of Biochemistry and Biophysics of the Polish Academy of Sciences, Warsaw, Poland
| | - Hanna Rekosz-Burlaga
- Department of Biochemistry and Microbiology, Institute of Biology, Warsaw University of Life Sciences (SGGW-WULS), Warsaw, Poland
| | - Robert Gromadka
- Institute of Biochemistry and Biophysics of the Polish Academy of Sciences, Warsaw, Poland
| | - Małgorzata Łobocka
- Institute of Biochemistry and Biophysics of the Polish Academy of Sciences, Warsaw, Poland
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2
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Letarov AV. Bacterial Virus Forcing of Bacterial O-Antigen Shields: Lessons from Coliphages. Int J Mol Sci 2023; 24:17390. [PMID: 38139217 PMCID: PMC10743462 DOI: 10.3390/ijms242417390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 12/05/2023] [Accepted: 12/07/2023] [Indexed: 12/24/2023] Open
Abstract
In most Gram-negative bacteria, outer membrane (OM) lipopolysaccharide (LPS) molecules carry long polysaccharide chains known as the O antigens or O polysaccharides (OPS). The OPS structure varies highly from strain to strain, with more than 188 O serotypes described in E. coli. Although many bacteriophages recognize OPS as their primary receptors, these molecules can also screen OM proteins and other OM surface receptors from direct interaction with phage receptor-binding proteins (RBP). In this review, I analyze the body of evidence indicating that most of the E. coli OPS types robustly shield cells completely, preventing phage access to the OM surface. This shield not only blocks virulent phages but also restricts the acquisition of prophages. The available data suggest that OPS-mediated OM shielding is not merely one of many mechanisms of bacterial resistance to phages. Rather, it is an omnipresent factor significantly affecting the ecology, phage-host co-evolution and other related processes in E. coli and probably in many other species of Gram-negative bacteria. The phages, in turn, evolved multiple mechanisms to break through the OPS layer. These mechanisms rely on the phage RBPs recognizing the OPS or on using alternative receptors exposed above the OPS layer. The data allow one to forward the interpretation that, regardless of the type of receptors used, primary receptor recognition is always followed by the generation of a mechanical force driving the phage tail through the OPS layer. This force may be created by molecular motors of enzymatically active tail spikes or by virion structural re-arrangements at the moment of infection.
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Affiliation(s)
- Andrey V Letarov
- Winogradsky Institute of Micrbiology, Research Center Fundamentals of Biotechnology RAS, pr. 60-letiya Oktyabrya 7 bld. 2, Moscow 117312, Russia
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Panhwar S, Keerio HA, Ilhan H, Boyacı IH, Tamer U. Principles, Methods, and Real-Time Applications of Bacteriophage-Based Pathogen Detection. Mol Biotechnol 2023:10.1007/s12033-023-00926-5. [PMID: 37914863 DOI: 10.1007/s12033-023-00926-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 10/02/2023] [Indexed: 11/03/2023]
Abstract
Bacterial pathogens in water, food, and the environment are spreading diseases around the world. According to a World Health Organization (WHO) report, waterborne pathogens pose the most significant global health risks to living organisms, including humans and animals. Conventional bacterial detection approaches such as colony counting, microscopic analysis, biochemical analysis, and molecular analysis are expensive, time-consuming, less sensitive, and require a pre-enrichment step. However, the bacteriophage-based detection of pathogenic bacteria is a robust approach that utilizes bacteriophages, which are viruses that specifically target and infect bacteria, for rapid and accurate detection of targets. This review shed light on cutting-edge technologies about the novel structure of phages and the immobilization process on the surface of electrodes to detect targeted bacterial cells. Similarly, the purpose of this study was to provide a comprehensive assessment of bacteriophage-based biosensors utilized for pathogen detection, as well as their trends, outcomes, and problems. This review article summaries current phage-based pathogen detection strategies for the development of low-cost lab-on-chip (LOC) and point-of-care (POC) devices using electrochemical and optical methods such as surface-enhanced Raman spectroscopy (SERS).
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Affiliation(s)
- Sallahuddin Panhwar
- Department of Analytical Chemistry, Faculty of Pharmacy, Gazi University, 06330, Ankara, Turkey.
- Department of Civil Engineering, National University of Sciences and Technology, Quetta, 24090, Balochistan, Pakistan.
| | - Hareef Ahmed Keerio
- Department of Civil and Environmental Engineering, Hanyang University, Seoul, Republic of Korea
| | - Hasan Ilhan
- Department of Chemistry, Faculty of Science, Ordu University, Altinordu, 52200, Ordu, Turkey
| | - Ismail Hakkı Boyacı
- Department of Food Engineering, Faculty of Engineering, Hacettepe University, Beytepe, 06800, Ankara, Turkey
| | - Ugur Tamer
- Department of Analytical Chemistry, Faculty of Pharmacy, Gazi University, 06330, Ankara, Turkey.
- Metu MEMS Center, Ankara, Turkey.
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4
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Kaplan M, Chang YW, Oikonomou CM, Nicolas WJ, Jewett AI, Kreida S, Dutka P, Rettberg LA, Maggi S, Jensen GJ. Bdellovibrio predation cycle characterized at nanometre-scale resolution with cryo-electron tomography. Nat Microbiol 2023; 8:1267-1279. [PMID: 37349588 PMCID: PMC11061892 DOI: 10.1038/s41564-023-01401-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 04/27/2023] [Indexed: 06/24/2023]
Abstract
Bdellovibrio bacteriovorus is a microbial predator that offers promise as a living antibiotic for its ability to kill Gram-negative bacteria, including human pathogens. Even after six decades of study, fundamental details of its predation cycle remain mysterious. Here we used cryo-electron tomography to comprehensively image the lifecycle of B. bacteriovorus at nanometre-scale resolution. With high-resolution images of predation in a native (hydrated, unstained) state, we discover several surprising features of the process, including macromolecular complexes involved in prey attachment/invasion and a flexible portal structure lining a hole in the prey peptidoglycan that tightly seals the prey outer membrane around the predator during entry. Unexpectedly, we find that B. bacteriovorus does not shed its flagellum during invasion, but rather resorbs it into its periplasm for degradation. Finally, following growth and division in the bdelloplast, we observe a transient and extensive ribosomal lattice on the condensed B. bacteriovorus nucleoid.
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Affiliation(s)
- Mohammed Kaplan
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.
- Department of Microbiology, University of Chicago, Chicago, IL, USA.
| | - Yi-Wei Chang
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Catherine M Oikonomou
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - William J Nicolas
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Andrew I Jewett
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Stefan Kreida
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Solna, Sweden
| | - Przemysław Dutka
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
| | | | - Stefano Maggi
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Grant J Jensen
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, USA.
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5
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Yang F, Wang L, Zhou J, Xiao H, Liu H. In Situ Structures of the Ultra-Long Extended and Contracted Tail of Myoviridae Phage P1. Viruses 2023; 15:1267. [PMID: 37376567 DOI: 10.3390/v15061267] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Revised: 05/20/2023] [Accepted: 05/27/2023] [Indexed: 06/29/2023] Open
Abstract
The Myoviridae phage tail is a common component of contractile injection systems (CISs), essential for exerting contractile function and facilitating membrane penetration of the inner tail tube. The near-atomic resolution structures of the Myoviridae tail have been extensively studied, but the dynamic conformational changes before and after contraction and the associated molecular mechanism are still unclear. Here, we present the extended and contracted intact tail-structures of Myoviridae phage P1 by cryo-EM. The ultra-long tail of P1, 2450 Å in length, consists of a neck, a tail terminator, 53 repeated tail sheath rings, 53 repeated tube rings, and a baseplate. The sheath of the contracted tail shrinks by approximately 55%, resulting in the separation of the inner rigid tail tube from the sheath. The extended and contracted tails were further resolved by local reconstruction at 3.3 Å and 3.9 Å resolutions, respectively, allowing us to build the atomic models of the tail terminator protein gp24, the tube protein BplB, and the sheath protein gp22 for the extended tail, and of the sheath protein gp22 for the contracted tail. Our atomic models reveal the complex interaction network in the ultra-long Myoviridae tail and the novel conformational changes of the tail sheath between extended and contracted states. Our structures provide insights into the contraction and stabilization mechanisms of the Myoviridae tail.
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Affiliation(s)
- Fan Yang
- Institute of Interdisciplinary Studies, Key Laboratory for Matter Microstructure and Function of Hunan Province, Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control, Hunan Normal University, Changsha 410082, China
| | - Liwen Wang
- Institute of Interdisciplinary Studies, Key Laboratory for Matter Microstructure and Function of Hunan Province, Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control, Hunan Normal University, Changsha 410082, China
| | - Junquan Zhou
- Institute of Interdisciplinary Studies, Key Laboratory for Matter Microstructure and Function of Hunan Province, Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control, Hunan Normal University, Changsha 410082, China
| | - Hao Xiao
- Institute of Interdisciplinary Studies, Key Laboratory for Matter Microstructure and Function of Hunan Province, Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control, Hunan Normal University, Changsha 410082, China
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 100052, China
| | - Hongrong Liu
- Institute of Interdisciplinary Studies, Key Laboratory for Matter Microstructure and Function of Hunan Province, Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control, Hunan Normal University, Changsha 410082, China
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Wang M, Jiang L, Wei J, Zhu H, Zhang J, Liu Z, Zhang W, He X, Liu Y, Li R, Xiao X, Sun Y, Zeng Z, Wang Z. Similarities of P1-Like Phage Plasmids and Their Role in the Dissemination of blaCTX-M-55. Microbiol Spectr 2022; 10:e0141022. [PMID: 36069562 PMCID: PMC9603915 DOI: 10.1128/spectrum.01410-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 08/18/2022] [Indexed: 12/30/2022] Open
Abstract
The P1-like phage plasmid (PP) has been widely used as a molecular biology tool, but its role as an active accessory cargo element is not fully understood. In this study, we provide insights into the structural features and gene content similarities of 77 P1-like PPs in the RefSeq database. We also describe a P1-like PP carrying a blaCTX-M-55 gene, JL22, which was isolated from a clinical strain of Escherichia coli from a duck farm. P1-like PPs were very similar and conserved based on gene content similarities, with only eight highly variable regions. Importantly, two kinds of replicon types, namely, IncY and p0111, were identified and can be used to specifically identify the P1-like phage. JL22 is similar to P1, acquiring an important foreign DNA fragment with two obvious features, namely, the plasmid replication gene repA' (p0111) replacing the gene repA (IncY) and a 4,200-bp fragment mobilized by IS1380 and IS5 and containing a blaCTX-M-55 gene and a trpB gene encoding tryptophan synthase (indole salvaging). The JL22 phage could be induced but had no lytic capacities. However, a lysogenic recipient and intact structure of JL22 virions were observed, showing that the extended-spectrum β-lactamase blaCTX-M-55 gene was successfully transferred. Overall, conserved genes can be a good complement to improve the identification efficiency and accuracy in future screening for P1-like PPs. Moreover, the highly conserved structures may be important for their prevalence and dissemination. IMPORTANCE As a PP, P1 DNA exists as a low-copy-number plasmid and replicates autonomously with a lysogenization style. This unique mode of P1-like elements probably indicates a stable contribution to antibiotic resistance. After analyzing these elements, we show that P1-like PPs are very similar and conserved, with only eight highly variable regions. Moreover, we observed the occurrence of replicon IncY and p0111 only in the P1-like PP community, implying that these conserved regions, coupled with IncY and p0111, can be an important complement in future screening of P1-like PPs. Identification and characterization of JL22 confirmed our findings that major changes were located in variable regions, including the first detection of blaCTX-M-55 in such a mobile genetic element. This suggests that these variable regions may facilitate foreign DNA mobilization. This study features a comprehensive genetic analysis of P1-like PPs, providing new insights into the dissemination mechanisms of antibiotic resistance through P1 PPs.
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Affiliation(s)
- Mianzhi Wang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
- Priority Academic Program Development of Jiangsu Higher Education Institutions, Yangzhou, China
| | - Li Jiang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
- Priority Academic Program Development of Jiangsu Higher Education Institutions, Yangzhou, China
| | - Jingyi Wei
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
- Priority Academic Program Development of Jiangsu Higher Education Institutions, Yangzhou, China
| | - Heng Zhu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
- Priority Academic Program Development of Jiangsu Higher Education Institutions, Yangzhou, China
| | - Junxuan Zhang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, Guangzhou, China
- National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, Guangzhou, China
| | - Ziyi Liu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
- Priority Academic Program Development of Jiangsu Higher Education Institutions, Yangzhou, China
| | - Wenhui Zhang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
- Priority Academic Program Development of Jiangsu Higher Education Institutions, Yangzhou, China
| | - Xiaolu He
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, Guangzhou, China
- National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, Guangzhou, China
| | - Yuan Liu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
- Priority Academic Program Development of Jiangsu Higher Education Institutions, Yangzhou, China
| | - Ruichao Li
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
- Priority Academic Program Development of Jiangsu Higher Education Institutions, Yangzhou, China
| | - Xia Xiao
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
- Priority Academic Program Development of Jiangsu Higher Education Institutions, Yangzhou, China
| | - Yongxue Sun
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, Guangzhou, China
- National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Zhenling Zeng
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, Guangzhou, China
- National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Zhiqiang Wang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
- Priority Academic Program Development of Jiangsu Higher Education Institutions, Yangzhou, China
- International Research Laboratory of Agriculture and Agri-Product Safety, Ministry of Education of China, Yangzhou, China
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Efimov AD, Golomidova AK, Kulikov EE, Belalov IS, Ivanov PA, Letarov AV. RB49-like Bacteriophages Recognize O Antigens as One of the Alternative Primary Receptors. Int J Mol Sci 2022; 23:ijms231911329. [PMID: 36232640 PMCID: PMC9569957 DOI: 10.3390/ijms231911329] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 09/16/2022] [Accepted: 09/19/2022] [Indexed: 11/16/2022] Open
Abstract
The power of most of the enterobacterial O antigen types to provide robust protection against direct recognition of the cell surface by bacteriophage receptor-recognition proteins (RBP) has been recently recognized. The bacteriophages infecting O antigen producing strains of E. coli employ various strategies to tackle this nonspecific protection. T-even related phages, including RB49-like viruses, often have wide host ranges, being considered good candidates for use in phage therapy. However, the mechanisms by which these phages overcome the O antigen barrier remain unknown. We demonstrate here that RB49 and related phages Cognac49 and Whisky49 directly use certain types of O antigen as their primary receptors recognized by the virus long tail fibers (LTF) RBP gp38, so the O antigen becomes an attractant instead of an obstacle. Simultaneously to recognize multiple O antigen types, LTFs of each of these phages can bind to additional receptors, such as OmpA protein, enabling them to infect some rough strains of E. coli. We speculate that the mechanical force of the deployment of the short tail fibers (STF) triggered by the LTF binding to the O antigen or underneath of it, allows the receptor binding domains of STF to break through the O polysaccharide layer.
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Affiliation(s)
- Alexandr D Efimov
- Laboratory of Microbial Viruses, Winogradsky Institute of Microbiology RC Biotechnology RAS, 117312 Moscow, Russia
| | - Alla K Golomidova
- Laboratory of Microbial Viruses, Winogradsky Institute of Microbiology RC Biotechnology RAS, 117312 Moscow, Russia
| | - Eugene E Kulikov
- Laboratory of Microbial Viruses, Winogradsky Institute of Microbiology RC Biotechnology RAS, 117312 Moscow, Russia
- Faculty of Biology, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Ilya S Belalov
- Laboratory of Microbial Viruses, Winogradsky Institute of Microbiology RC Biotechnology RAS, 117312 Moscow, Russia
| | - Pavel A Ivanov
- Laboratory of Microbial Viruses, Winogradsky Institute of Microbiology RC Biotechnology RAS, 117312 Moscow, Russia
| | - Andrey V Letarov
- Laboratory of Microbial Viruses, Winogradsky Institute of Microbiology RC Biotechnology RAS, 117312 Moscow, Russia
- Faculty of Biology, Lomonosov Moscow State University, 119991 Moscow, Russia
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8
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Gonzales MF, Piya DK, Koehler B, Zhang K, Yu Z, Zeng L, Gill JJ. New Insights into the Structure and Assembly of Bacteriophage P1. Viruses 2022; 14:v14040678. [PMID: 35458408 PMCID: PMC9024508 DOI: 10.3390/v14040678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 03/10/2022] [Accepted: 03/16/2022] [Indexed: 12/10/2022] Open
Abstract
Bacteriophage P1 is the premier transducing phage of E. coli. Despite its prominence in advancing E. coli genetics, modern molecular techniques have not been applied to thoroughly understand P1 structure. Here, we report the proteome of the P1 virion as determined by liquid chromatography tandem mass-spectrometry. Additionally, a library of single-gene knockouts identified the following five previously unknown essential genes: pmgA, pmgB, pmgC, pmgG, and pmgR. In addition, proteolytic processing of the major capsid protein is a known feature of P1 morphogenesis, and we identified the processing site by N-terminal sequencing to be between E120 and S121, producing a 448-residue, 49.3 kDa mature peptide. Furthermore, the P1 defense against restriction (Dar) system consists of six known proteins that are incorporated into the virion during morphogenesis. The largest of these, DarB, is a 250 kDa protein that is believed to translocate into the cell during infection. DarB deletions indicated the presence of an N-terminal packaging signal, and the N-terminal 30 residues of DarB are shown to be sufficient for directing a heterologous reporter protein to the capsid. Taken together, the data expand on essential structural P1 proteins as well as introduces P1 as a nanomachine for cellular delivery.
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Affiliation(s)
- Miguel F. Gonzales
- Center for Phage Technology, Texas A&M University, 2128 TAMU, College Station, TX 77843, USA; (M.F.G.); (D.K.P.); (K.Z.); (Z.Y.); (L.Z.)
- Interdisciplinary Program in Genetics, Texas A&M University, 2128 TAMU, College Station, TX 77843, USA
| | - Denish K. Piya
- Center for Phage Technology, Texas A&M University, 2128 TAMU, College Station, TX 77843, USA; (M.F.G.); (D.K.P.); (K.Z.); (Z.Y.); (L.Z.)
- Department of Biochemistry and Biophysics, Texas A&M University, 2128 TAMU, College Station, TX 77843, USA;
| | - Brian Koehler
- Department of Biochemistry and Biophysics, Texas A&M University, 2128 TAMU, College Station, TX 77843, USA;
| | - Kailun Zhang
- Center for Phage Technology, Texas A&M University, 2128 TAMU, College Station, TX 77843, USA; (M.F.G.); (D.K.P.); (K.Z.); (Z.Y.); (L.Z.)
- Department of Biochemistry and Biophysics, Texas A&M University, 2128 TAMU, College Station, TX 77843, USA;
| | - Zihao Yu
- Center for Phage Technology, Texas A&M University, 2128 TAMU, College Station, TX 77843, USA; (M.F.G.); (D.K.P.); (K.Z.); (Z.Y.); (L.Z.)
- Department of Biochemistry and Biophysics, Texas A&M University, 2128 TAMU, College Station, TX 77843, USA;
| | - Lanying Zeng
- Center for Phage Technology, Texas A&M University, 2128 TAMU, College Station, TX 77843, USA; (M.F.G.); (D.K.P.); (K.Z.); (Z.Y.); (L.Z.)
- Department of Biochemistry and Biophysics, Texas A&M University, 2128 TAMU, College Station, TX 77843, USA;
| | - Jason J. Gill
- Center for Phage Technology, Texas A&M University, 2128 TAMU, College Station, TX 77843, USA; (M.F.G.); (D.K.P.); (K.Z.); (Z.Y.); (L.Z.)
- Interdisciplinary Program in Genetics, Texas A&M University, 2128 TAMU, College Station, TX 77843, USA
- Department of Animal Science, Texas A&M University, 2471 TAMU, College Station, TX 77843, USA
- Correspondence: ; Tel.: +1-979-458-6368
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Fraser A, Prokhorov NS, Jiao F, Pettitt BM, Scheuring S, Leiman PG. Quantitative description of a contractile macromolecular machine. SCIENCE ADVANCES 2021; 7:7/24/eabf9601. [PMID: 34117062 PMCID: PMC8195476 DOI: 10.1126/sciadv.abf9601] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 04/23/2021] [Indexed: 05/14/2023]
Abstract
Contractile injection systems (CISs) [type VI secretion system (T6SS), phage tails, and tailocins] use a contractile sheath-rigid tube machinery to breach cell walls and lipid membranes. The structures of the pre- and postcontraction states of several CISs are known, but the mechanism of contraction remains poorly understood. Combining structural information of the end states of the 12-megadalton R-type pyocin sheath-tube complex with thermodynamic and force spectroscopy analyses and an original modeling procedure, we describe the mechanism of pyocin contraction. We show that this nanomachine has an activation energy of 160 kilocalories/mole (kcal/mol), and it releases 2160 kcal/mol of heat and develops a force greater than 500 piconewtons. Our combined approach provides a quantitative and experimental description of the membrane penetration process by a CIS.
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Affiliation(s)
- Alec Fraser
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics (SCSB), The University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Nikolai S Prokhorov
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics (SCSB), The University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Fang Jiao
- Department of Anesthesiology, Weill Cornell Medicine, 1300 York Avenue, New York, NY 10065, USA
- Department of Physiology and Biophysics, Weill Cornell Medicine, 1300 York Avenue, New York, NY 10065, USA
| | - B Montgomery Pettitt
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics (SCSB), The University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Simon Scheuring
- Department of Anesthesiology, Weill Cornell Medicine, 1300 York Avenue, New York, NY 10065, USA.
- Department of Physiology and Biophysics, Weill Cornell Medicine, 1300 York Avenue, New York, NY 10065, USA
| | - Petr G Leiman
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics (SCSB), The University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
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10
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Dunne M, Prokhorov NS, Loessner MJ, Leiman PG. Reprogramming bacteriophage host range: design principles and strategies for engineering receptor binding proteins. Curr Opin Biotechnol 2021; 68:272-281. [PMID: 33744824 PMCID: PMC10163921 DOI: 10.1016/j.copbio.2021.02.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 02/09/2021] [Accepted: 02/19/2021] [Indexed: 01/09/2023]
Abstract
Bacteriophages (phages) use specialized tail machinery to deliver proteins and genetic material into a bacterial cell during infection. Attached at the distal ends of their tails are receptor binding proteins (RBPs) that recognize specific molecules exposed on host bacteria surfaces. Since the therapeutic capacity of naturally occurring phages is often limited by narrow host ranges, there is significant interest in expanding their host range via directed evolution or structure-guided engineering of their RBPs. Here, we describe the design principles of different RBP engineering platforms and draw attention to the mechanisms linking RBP binding and the correct spatial and temporal attachment of the phage to the bacterial surface. A deeper understanding of these mechanisms will directly benefit future engineering of more effective phage-based therapeutics.
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Affiliation(s)
- Matthew Dunne
- Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, 8092, Zurich, Switzerland.
| | - Nikolai S Prokhorov
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, USA
| | - Martin J Loessner
- Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, 8092, Zurich, Switzerland
| | - Petr G Leiman
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, USA
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11
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Abraham S, Kaufman Y, Perreault F, Young R, Bar-Zeev E. Bursting out: linking changes in nanotopography and biomechanical properties of biofilm-forming Escherichia coli to the T4 lytic cycle. NPJ Biofilms Microbiomes 2021; 7:26. [PMID: 33731698 PMCID: PMC7969764 DOI: 10.1038/s41522-021-00195-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 01/20/2021] [Indexed: 11/09/2022] Open
Abstract
The bacteriophage infection cycle has been extensively studied, yet little is known about the nanostructure and mechanical changes that lead to bacterial lysis. Here, atomic force microscopy was used to study in real time and in situ the impact of the canonical phage T4 on the nanotopography and biomechanics of irreversibly attached, biofilm-forming E. coli cells. The results show that in contrast to the lytic cycle in planktonic cells, which ends explosively, anchored cells that are in the process of forming a biofilm undergo a more gradual lysis, developing distinct nanoscale lesions (~300 nm in diameter) within the cell envelope. Furthermore, it is shown that the envelope rigidity and cell elasticity decrease (>50% and >40%, respectively) following T4 infection, a process likely linked to changes in the nanostructure of infected cells. These insights show that the well-established lytic pathway of planktonic cells may be significantly different from that of biofilm-forming cells. Elucidating the lysis paradigm of these cells may advance biofilm removal and phage therapeutics.
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Affiliation(s)
- Shiju Abraham
- Zuckerberg Institute for Water Research, The Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sde Boqer Campus, Midreshet Ben-Gurion, Israel
| | - Yair Kaufman
- Zuckerberg Institute for Water Research, The Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sde Boqer Campus, Midreshet Ben-Gurion, Israel.
| | - François Perreault
- School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, AZ, USA
| | - Ry Young
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA
- Texas A&M AgriLife, College Station, TX, USA
| | - Edo Bar-Zeev
- Zuckerberg Institute for Water Research, The Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sde Boqer Campus, Midreshet Ben-Gurion, Israel.
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12
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Quemin ERJ, Machala EA, Vollmer B, Pražák V, Vasishtan D, Rosch R, Grange M, Franken LE, Baker LA, Grünewald K. Cellular Electron Cryo-Tomography to Study Virus-Host Interactions. Annu Rev Virol 2020; 7:239-262. [PMID: 32631159 DOI: 10.1146/annurev-virology-021920-115935] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Viruses are obligatory intracellular parasites that reprogram host cells upon infection to produce viral progeny. Here, we review recent structural insights into virus-host interactions in bacteria, archaea, and eukaryotes unveiled by cellular electron cryo-tomography (cryoET). This advanced three-dimensional imaging technique of vitreous samples in near-native state has matured over the past two decades and proven powerful in revealing molecular mechanisms underlying viral replication. Initial studies were restricted to cell peripheries and typically focused on early infection steps, analyzing surface proteins and viral entry. Recent developments including cryo-thinning techniques, phase-plate imaging, and correlative approaches have been instrumental in also targeting rare events inside infected cells. When combined with advances in dedicated image analyses and processing methods, details of virus assembly and egress at (sub)nanometer resolution were uncovered. Altogether, we provide a historical and technical perspective and discuss future directions and impacts of cryoET for integrative structural cell biology analyses of viruses.
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Affiliation(s)
- Emmanuelle R J Quemin
- Centre for Structural Systems Biology, Heinrich-Pette-Institute, Leibniz Institute for Experimental Virology, University of Hamburg, D-22607 Hamburg, Germany;
| | - Emily A Machala
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, United Kingdom
| | - Benjamin Vollmer
- Centre for Structural Systems Biology, Heinrich-Pette-Institute, Leibniz Institute for Experimental Virology, University of Hamburg, D-22607 Hamburg, Germany;
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, United Kingdom
| | - Vojtěch Pražák
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, United Kingdom
| | - Daven Vasishtan
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, United Kingdom
| | - Rene Rosch
- Centre for Structural Systems Biology, Heinrich-Pette-Institute, Leibniz Institute for Experimental Virology, University of Hamburg, D-22607 Hamburg, Germany;
| | - Michael Grange
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, United Kingdom
| | - Linda E Franken
- Centre for Structural Systems Biology, Heinrich-Pette-Institute, Leibniz Institute for Experimental Virology, University of Hamburg, D-22607 Hamburg, Germany;
| | - Lindsay A Baker
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, United Kingdom
| | - Kay Grünewald
- Centre for Structural Systems Biology, Heinrich-Pette-Institute, Leibniz Institute for Experimental Virology, University of Hamburg, D-22607 Hamburg, Germany;
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, United Kingdom
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13
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Zhang K, Young R, Zeng L. Bacteriophage P1 does not show spatial preference when infecting Escherichia coli. Virology 2020; 542:1-7. [PMID: 31957661 PMCID: PMC7024032 DOI: 10.1016/j.virol.2019.12.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 12/02/2019] [Accepted: 12/30/2019] [Indexed: 11/16/2022]
Abstract
To begin its infection, a bacteriophage first needs to adsorb to cells. The adsorption site on the cell surface may influence viral DNA injection, gene expression and cell-fate development. Here, we study the early steps of the infection cycle of coliphage P1, focusing on their correlation with spatial locations at the single-cell level. By fluorescently labeling P1 virions, we found that P1 shows no spatial preference on cell surface adsorption. In addition, live-cell phage DNA imaging revealed that adsorption sites do not affect the success rate for P1 in injecting its DNA into the cell. Furthermore, the lysis-lysogeny decision of P1 does not depend on the adsorption site, based on fluorescence reporters for the lytic and lysogenic pathways. These findings highlight the different infection strategies used by the two paradigmatic coliphages differ from those found in the paradigmatic phage lambda, highlighting that different infection strategies are used by phages.
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Affiliation(s)
- Kailun Zhang
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, 77843, USA; Center for Phage Technology, Texas A&M University, College Station, TX, 77843, USA
| | - Ry Young
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, 77843, USA; Center for Phage Technology, Texas A&M University, College Station, TX, 77843, USA
| | - Lanying Zeng
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, 77843, USA; Center for Phage Technology, Texas A&M University, College Station, TX, 77843, USA.
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14
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Burt A, Cassidy CK, Ames P, Bacia-Verloop M, Baulard M, Huard K, Luthey-Schulten Z, Desfosses A, Stansfeld PJ, Margolin W, Parkinson JS, Gutsche I. Complete structure of the chemosensory array core signalling unit in an E. coli minicell strain. Nat Commun 2020; 11:743. [PMID: 32029744 PMCID: PMC7005262 DOI: 10.1038/s41467-020-14350-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 12/21/2019] [Indexed: 12/01/2022] Open
Abstract
Motile bacteria sense chemical gradients with transmembrane receptors organised in supramolecular signalling arrays. Understanding stimulus detection and transmission at the molecular level requires precise structural characterisation of the array building block known as a core signalling unit. Here we introduce an Escherichia coli strain that forms small minicells possessing extended and highly ordered chemosensory arrays. We use cryo-electron tomography and subtomogram averaging to provide a three-dimensional map of a complete core signalling unit, with visible densities corresponding to the HAMP and periplasmic domains. This map, combined with previously determined high resolution structures and molecular dynamics simulations, yields a molecular model of the transmembrane core signalling unit and enables spatial localisation of its individual domains. Our work thus offers a solid structural basis for the interpretation of a wide range of existing data and the design of further experiments to elucidate signalling mechanisms within the core signalling unit and larger array.
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Affiliation(s)
- Alister Burt
- Institut de Biologie Structurale, Université Grenoble Alpes, CEA, CNRS, IBS, 71 Avenue des martyrs, F-38044, Grenoble, France
| | - C Keith Cassidy
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | - Peter Ames
- School of Biological Sciences, University of Utah, Salt Lake City, UT, 84112, USA
| | - Maria Bacia-Verloop
- Institut de Biologie Structurale, Université Grenoble Alpes, CEA, CNRS, IBS, 71 Avenue des martyrs, F-38044, Grenoble, France
| | - Megghane Baulard
- Institut de Biologie Structurale, Université Grenoble Alpes, CEA, CNRS, IBS, 71 Avenue des martyrs, F-38044, Grenoble, France
| | - Karine Huard
- Institut de Biologie Structurale, Université Grenoble Alpes, CEA, CNRS, IBS, 71 Avenue des martyrs, F-38044, Grenoble, France
| | - Zaida Luthey-Schulten
- Department of Chemistry, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Ambroise Desfosses
- Institut de Biologie Structurale, Université Grenoble Alpes, CEA, CNRS, IBS, 71 Avenue des martyrs, F-38044, Grenoble, France
| | - Phillip J Stansfeld
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | - William Margolin
- Department of Microbiology & Molecular Genetics, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - John S Parkinson
- School of Biological Sciences, University of Utah, Salt Lake City, UT, 84112, USA
| | - Irina Gutsche
- Institut de Biologie Structurale, Université Grenoble Alpes, CEA, CNRS, IBS, 71 Avenue des martyrs, F-38044, Grenoble, France.
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15
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Dearnaley WJ, Schleupner B, Varano AC, Alden NA, Gonzalez F, Casasanta MA, Scharf BE, Dukes MJ, Kelly DF. Liquid-Cell Electron Tomography of Biological Systems. NANO LETTERS 2019; 19:6734-6741. [PMID: 31244227 PMCID: PMC6786937 DOI: 10.1021/acs.nanolett.9b01309] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Liquid-cell electron microscopy is a rapidly growing field in the imaging domain. While real-time observations are readily available to analyze materials and biological systems, these measurementshave been limited to the two-dimensional (2-D) image plane. Here, we introduce an exciting technical advance to image materials in 3-D while enclosed in liquid. The development of liquid-cell electron tomography permitted us to observe and quantify host-pathogen interactions in solution while contained in the vacuum system of the electron microscope. In doing so, we demonstrate new insights for the rules of engagement involving a unique bacteriophage and its host bacterium. A deeper analysis of the genetic content of the phage pathogens revealed structural features of the infectious units while introducing a new paradigm for host interactions. Overall, we demonstrate a technological opportunity to elevate research efforts for in situ imaging while providing a new level of dimensionality beyond the current state of the field.
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Affiliation(s)
- William J. Dearnaley
- Department of Biomedical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Center for Structural Oncology, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Virginia Tech Carilion Research Institute, Virginia Tech, Roanoke, Virginia 24016, United States
| | - Beatrice Schleupner
- Virginia Tech Carilion Research Institute, Virginia Tech, Roanoke, Virginia 24016, United States
| | - A. Cameron Varano
- Department of Biomedical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Center for Structural Oncology, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Virginia Tech Carilion Research Institute, Virginia Tech, Roanoke, Virginia 24016, United States
| | - Nick A. Alden
- Department of Biomedical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Virginia Tech Carilion Research Institute, Virginia Tech, Roanoke, Virginia 24016, United States
| | - Floricel Gonzalez
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Michael A. Casasanta
- Department of Biomedical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Center for Structural Oncology, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Birgit E. Scharf
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Madeline J. Dukes
- Applications Science, Protochips Inc., Morrisville, North Carolina 27560, United States
| | - Deborah F. Kelly
- Department of Biomedical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Center for Structural Oncology, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Virginia Tech Carilion Research Institute, Virginia Tech, Roanoke, Virginia 24016, United States
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16
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McNulty R, Cardone G, Gilcrease EB, Baker TS, Casjens SR, Johnson JE. Cryo-EM Elucidation of the Structure of Bacteriophage P22 Virions after Genome Release. Biophys J 2019; 114:1295-1301. [PMID: 29590587 DOI: 10.1016/j.bpj.2018.01.026] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 12/24/2017] [Accepted: 01/17/2018] [Indexed: 11/19/2022] Open
Abstract
Genome ejection proteins are required to facilitate transport of bacteriophage P22 double-stranded DNA safely through membranes of Salmonella. The structures and locations of all proteins in the context of the mature virion are known, with the exception of three ejection proteins. Furthermore, the changes that occur to the proteins residing in the mature virion upon DNA release are not fully understood. We used cryogenic electron microscopy to obtain what is, to our knowledge, the first asymmetric reconstruction of mature bacteriophage P22 after double-stranded DNA has been extruded from the capsid-a state representative of one step during viral infection. Results of icosahedral and asymmetric reconstructions at estimated resolutions of 7.8 and 12.5 Å resolutions, respectively, are presented. The reconstruction shows tube-like protein density extending from the center of the tail assembly. The portal protein does not revert to the more contracted, procapsid state, but instead maintains an extended and splayed barrel structure. These structural details contribute to our understanding of the molecular mechanism of P22 phage infection and also set the foundation for future exploitation serving engineering purposes.
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Affiliation(s)
- Reginald McNulty
- Laboratory of Gene Regulation and Signal Transduction, Department of Pharmacology, School of Medicine, University of California, San Diego, La Jolla, California.
| | - Giovanni Cardone
- Department of Chemistry and BiochemistryUniversity of California, San Diego, La Jolla, California
| | - Eddie B Gilcrease
- Division of Microbiology and Immunology, Pathology Department, University of Utah School of Medicine, Salt Lake City, Utah
| | - Timothy S Baker
- Department of Chemistry and BiochemistryUniversity of California, San Diego, La Jolla, California; Division of Biological Sciences, University of California, San Diego, La Jolla, California
| | - Sherwood R Casjens
- Division of Microbiology and Immunology, Pathology Department, University of Utah School of Medicine, Salt Lake City, Utah
| | - John E Johnson
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California.
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17
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Cyrklaff M, Frischknecht F, Kudryashev M. Functional insights into pathogen biology from 3D electron microscopy. FEMS Microbiol Rev 2018; 41:828-853. [PMID: 28962014 DOI: 10.1093/femsre/fux041] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 07/25/2017] [Indexed: 01/10/2023] Open
Abstract
In recent years, novel imaging approaches revolutionised our understanding of the cellular and molecular biology of microorganisms. These include advances in fluorescent probes, dynamic live cell imaging, superresolution light and electron microscopy. Currently, a major transition in the experimental approach shifts electron microscopy studies from a complementary technique to a method of choice for structural and functional analysis. Here we review functional insights into the molecular architecture of viruses, bacteria and parasites as well as interactions with their respective host cells gained from studies using cryogenic electron tomography and related methodologies.
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Affiliation(s)
- Marek Cyrklaff
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Friedrich Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Mikhail Kudryashev
- Max Planck Institute of Biophysics, Max-von-Laue Strasse 3, 60438 Frankfurt, Germany.,Buchmann Institute for Molecular Life Sciences, Goethe University of Frankfurt, Max-von-Laue Strasse 17, 60438 Frankfurt, Germany
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18
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Letarov AV, Kulikov EE. Adsorption of bacteriophages on bacterial cells. BIOCHEMISTRY (MOSCOW) 2018. [DOI: 10.1134/s0006297917130053] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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19
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Henderson JC, Herrera CM, Trent MS. AlmG, responsible for polymyxin resistance in pandemic Vibrio cholerae, is a glycyltransferase distantly related to lipid A late acyltransferases. J Biol Chem 2017; 292:21205-21215. [PMID: 29101229 DOI: 10.1074/jbc.ra117.000131] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 10/19/2017] [Indexed: 12/21/2022] Open
Abstract
Cationic antimicrobial peptides (CAMPs), such as polymyxins, are used as a last-line defense in treatment of many bacterial infections. However, some bacteria have developed resistance mechanisms to survive these compounds. Current pandemic O1 Vibrio cholerae biotype El Tor is resistant to polymyxins, whereas a previous pandemic strain of the biotype Classical is polymyxin-sensitive. The almEFG operon found in El Tor V. cholerae confers >100-fold resistance to antimicrobial peptides through aminoacylation of lipopolysaccharide (LPS), expected to decrease the negatively charged surface of the V. cholerae outer membrane. This Gram-negative system bears striking resemblance to a related Gram-positive cell-wall remodeling strategy that also promotes CAMP resistance. Mutants defective in AlmEF-dependent LPS modification exhibit reduced fitness in vivo Here, we present investigation of AlmG, the hitherto uncharacterized member of the AlmEFG pathway. Evidence for AlmG glycyl to lipid substrate transferase activity is demonstrated in vivo by heterologous expression of V. cholerae pathway enzymes in a specially engineered Escherichia coli strain. Development of a minimal keto-deoxyoctulosonate (Kdo)-lipid A domain in E. coli was necessary to facilitate chemical structure analysis and to produce a mimetic Kdo-lipid A domain AlmG substrate to that synthesized by V. cholerae. Our biochemical studies support a uniquely nuanced pathway of Gram-negative CAMPs resistance and provide a more detailed description of an enzyme of the pharmacologically relevant lysophosphospholipid acyltransferase (LPLAT) superfamily.
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Affiliation(s)
- Jeremy C Henderson
- From the Department of Infectious Diseases, Center for Vaccines and Immunology, College of Veterinary Medicine, University of Georgia, Athens, Georgia 30602
| | - Carmen M Herrera
- From the Department of Infectious Diseases, Center for Vaccines and Immunology, College of Veterinary Medicine, University of Georgia, Athens, Georgia 30602
| | - M Stephen Trent
- From the Department of Infectious Diseases, Center for Vaccines and Immunology, College of Veterinary Medicine, University of Georgia, Athens, Georgia 30602
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20
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Martinez-Hernandez F, Fornas O, Lluesma Gomez M, Bolduc B, de la Cruz Peña MJ, Martínez JM, Anton J, Gasol JM, Rosselli R, Rodriguez-Valera F, Sullivan MB, Acinas SG, Martinez-Garcia M. Single-virus genomics reveals hidden cosmopolitan and abundant viruses. Nat Commun 2017; 8:15892. [PMID: 28643787 PMCID: PMC5490008 DOI: 10.1038/ncomms15892] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 05/10/2017] [Indexed: 12/22/2022] Open
Abstract
Microbes drive ecosystems under constraints imposed by viruses. However, a lack of virus genome information hinders our ability to answer fundamental, biological questions concerning microbial communities. Here we apply single-virus genomics (SVGs) to assess whether portions of marine viral communities are missed by current techniques. The majority of the here-identified 44 viral single-amplified genomes (vSAGs) are more abundant in global ocean virome data sets than published metagenome-assembled viral genomes or isolates. This indicates that vSAGs likely best represent the dsDNA viral populations dominating the oceans. Species-specific recruitment patterns and virome simulation data suggest that vSAGs are highly microdiverse and that microdiversity hinders the metagenomic assembly, which could explain why their genomes have not been identified before. Altogether, SVGs enable the discovery of some of the likely most abundant and ecologically relevant marine viral species, such as vSAG 37-F6, which were overlooked by other methodologies.
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Affiliation(s)
- Francisco Martinez-Hernandez
- Department of Physiology, Genetics, and Microbiology, University of Alicante, Carretera San Vicente del Raspeig, San Vicente del Raspeig, Alicante 03690, Spain
| | - Oscar Fornas
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology (BIST), Carrer del Doctor Aiguader, 88, PRBB Building, Barcelona 08003, Spain
- Universitat Pompeu Fabra (UPF), Carrer del Doctor Aiguader, 88, PRBB Building, Barcelona 08003, Spain
| | - Monica Lluesma Gomez
- Department of Physiology, Genetics, and Microbiology, University of Alicante, Carretera San Vicente del Raspeig, San Vicente del Raspeig, Alicante 03690, Spain
| | - Benjamin Bolduc
- Department of Microbiology, The Ohio State University, 105 Biological Sciences Building, 484 West 12th Avenue Columbus, Ohio 43210, USA
| | - Maria Jose de la Cruz Peña
- Department of Physiology, Genetics, and Microbiology, University of Alicante, Carretera San Vicente del Raspeig, San Vicente del Raspeig, Alicante 03690, Spain
| | - Joaquín Martínez Martínez
- Bigelow Laboratory for Ocean Sciences, 60 Bigelow Drive, PO Box 380, East Boothbay, Maine 04544, USA
| | - Josefa Anton
- Department of Physiology, Genetics, and Microbiology, University of Alicante, Carretera San Vicente del Raspeig, San Vicente del Raspeig, Alicante 03690, Spain
| | - Josep M. Gasol
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar (ICM), CSIC, Passeig Marítim, 47, Barcelona 08003, Spain
| | - Riccardo Rosselli
- Evolutionary Genomics Group, Departamento de Producción Vegetal y Microbiología, Universidad Miguel Hernández, Campus San Juan, San Juan, Alicante 03550, Spain
| | - Francisco Rodriguez-Valera
- Evolutionary Genomics Group, Departamento de Producción Vegetal y Microbiología, Universidad Miguel Hernández, Campus San Juan, San Juan, Alicante 03550, Spain
| | - Matthew B. Sullivan
- Department of Microbiology, The Ohio State University, 105 Biological Sciences Building, 484 West 12th Avenue Columbus, Ohio 43210, USA
- Department of Civil, Environmental and Geodetic Engineering, The Ohio State University, The Ohio State University, 105 Biological Sciences Building, 484 West 12th Avenue Columbus, Ohio 43210, USA
| | - Silvia G. Acinas
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar (ICM), CSIC, Passeig Marítim, 47, Barcelona 08003, Spain
| | - Manuel Martinez-Garcia
- Department of Physiology, Genetics, and Microbiology, University of Alicante, Carretera San Vicente del Raspeig, San Vicente del Raspeig, Alicante 03690, Spain
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21
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Tu J, Park T, Morado DR, Hughes KT, Molineux IJ, Liu J. Dual host specificity of phage SP6 is facilitated by tailspike rotation. Virology 2017; 507:206-215. [PMID: 28456019 DOI: 10.1016/j.virol.2017.04.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 04/13/2017] [Accepted: 04/17/2017] [Indexed: 01/08/2023]
Abstract
Bacteriophage SP6 exhibits dual-host adsorption specificity. The SP6 tailspikes are recognized as important in host range determination but the mechanisms underlying dual host specificity are unknown. Cryo-electron tomography and sub-tomogram classification were used to analyze the SP6 virion with a particular focus on the interaction of tailspikes with host membranes. The SP6 tail is surrounded by six V-shaped structures that interconnect in forming a hand-over-hand hexameric garland. Each V-shaped structure consists of two trimeric tailspike proteins: gp46 and gp47, connected through the adaptor protein gp37. SP6 infection of Salmonella enterica serovars Typhimurium and Newport results in distinguishable changes in tailspike orientation, providing the first direct demonstration how tailspikes can confer dual host adsorption specificity. SP6 also infects S. Typhimurium strains lacking O antigen; in these infections tailspikes have no apparent specific role and the phage tail must therefore interact with a distinct host receptor to allow infection.
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Affiliation(s)
- Jiagang Tu
- Department of Pathology and Laboratory Medicine, McGovern Medical School at UTHealth, Houston, TX 77030, USA
| | - Taehyun Park
- Center for Infectious Disease, Department of Molecular Biosciences, Institute for Cell and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA
| | - Dustin R Morado
- Department of Pathology and Laboratory Medicine, McGovern Medical School at UTHealth, Houston, TX 77030, USA
| | - Kelly T Hughes
- Department of Biology, University of Utah, Salt Lake City, UT 84112, USA
| | - Ian J Molineux
- Center for Infectious Disease, Department of Molecular Biosciences, Institute for Cell and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA.
| | - Jun Liu
- Department of Pathology and Laboratory Medicine, McGovern Medical School at UTHealth, Houston, TX 77030, USA.
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22
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Baltus RE, Badireddy AR, Delavari A, Chellam S. Free Diffusivity of Icosahedral and Tailed Bacteriophages: Experiments, Modeling, and Implications for Virus Behavior in Media Filtration and Flocculation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:1433-1440. [PMID: 28035813 DOI: 10.1021/acs.est.6b05323] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The aqueous bulk diffusivities of several near-spherical (icosahedral) and nonspherical (tailed) bacterial viruses were experimentally determined by measuring their flux across large pore membranes and using dynamic light scattering, with excellent agreement between values measured using the two techniques. For the icosahedral viruses, good agreement was also found between measured diffusivity values and values predicted with the Stokes-Einstein equation. However, when the tailed viruses were approximated as spheres, poor agreement was found between measured values and Stokes-Einstein predictions. The shape of the tailed organisms was incorporated into two modeling approaches used to predict diffusivity. Model predictions were found to be in good agreement with measured values, demonstrating the importance of the tail in the diffusive transport of these viruses. Our calculations also show that inaccurate estimates of virus diffusion can lead to significant errors when predicting diffusive contributions to flocculation and to single collector efficiency in media filtration.
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Affiliation(s)
- Ruth E Baltus
- Department of Chemical and Biomolecular Engineering, Clarkson University , Potsdam, New York 13699-5705, United States
| | - Appala Raju Badireddy
- Department of Civil and Environmental Engineering, University of Vermont , Burlington, Vermont 05405, United States
| | - Armin Delavari
- Department of Chemical and Biomolecular Engineering, Clarkson University , Potsdam, New York 13699-5705, United States
| | - Shankararaman Chellam
- Department of Civil Engineering, Texas A&M University , College Station, Texas 77843-3136, United States
- Department of Chemical Engineering, Texas A&M University , College Station, Texas 77843-3122, United States
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23
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Kennedy E, Nelson EM, Damiano J, Timp G. Gene Expression in Electron-Beam-Irradiated Bacteria in Reply to "Live Cell Electron Microscopy Is Probably Impossible". ACS NANO 2017; 11:3-7. [PMID: 28114765 DOI: 10.1021/acsnano.6b06616] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Affiliation(s)
- Eamonn Kennedy
- Department of Electrical Engineering, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Edward M Nelson
- Department of Electrical Engineering, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - John Damiano
- Protochips, Inc. , Morrisville, North Carolina 27560, United States
| | - Gregory Timp
- Departments of Electrical Engineering and Biological Science, University of Notre Dame , Notre Dame, Indiana 46556, United States
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24
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Farley MM, Tu J, Kearns DB, Molineux IJ, Liu J. Ultrastructural analysis of bacteriophage Φ29 during infection of Bacillus subtilis. J Struct Biol 2016; 197:163-171. [PMID: 27480510 DOI: 10.1016/j.jsb.2016.07.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 07/26/2016] [Accepted: 07/28/2016] [Indexed: 12/13/2022]
Abstract
Recent advances in cryo-electron tomography (cryo-ET) have allowed direct visualization of the initial interactions between bacteriophages and their hosts. Previous studies focused on phage infection in Gram-negative bacteria but it is of particular interest how phages penetrate the thick, highly cross-linked Gram-positive cell wall. Here we detail structural intermediates of phage Φ29 during infection of Bacillus subtilis. Use of a minicell-producing strain facilitated in situ tomographic reconstructions of infecting phage particles. Φ29 initially contacts the cell wall at an angle through a subset of the twelve appendages, which are attached to the collar at the head proximal portion of the tail knob. The appendages are flexible and switch between extended and downward conformations during this stage of reversible adsorption; appendages enzymatically hydrolyze wall teichoic acids to bring the phage closer to the cell. A cell wall-degrading enzyme at the distal tip of the tail knob locally digests peptidoglycan, facilitating penetration of the tail further into the cell wall, and the phage particle reorients so that the tail becomes perpendicular to the cell surface. All twelve appendages attain the same "down" conformation during this stage of adsorption. Once the tail has become totally embedded in the cell wall, the tip can fuse with the cytoplasmic membrane. The membrane bulges out, presumably to facilitate genome ejection into the cytoplasm, and the deformation remains after complete ejection. This study provides the first visualization of the structural changes occurring in a phage particle during adsorption and genome transfer into a Gram-positive bacterium.
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Affiliation(s)
- Madeline M Farley
- Department of Pathology and Laboratory Medicine, University of Texas Medical School at Houston, Houston, TX 77030, USA
| | - Jiagang Tu
- Department of Pathology and Laboratory Medicine, University of Texas Medical School at Houston, Houston, TX 77030, USA
| | - Daniel B Kearns
- Department of Biology, Indiana University, 1001 East Third Street, Bloomington, IN 47405, USA
| | - Ian J Molineux
- Center for Infectious Disease, Department of Molecular Biosciences, Institute for Cell and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA.
| | - Jun Liu
- Department of Pathology and Laboratory Medicine, University of Texas Medical School at Houston, Houston, TX 77030, USA.
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25
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Taylor NMI, Prokhorov NS, Guerrero-Ferreira RC, Shneider MM, Browning C, Goldie KN, Stahlberg H, Leiman PG. Structure of the T4 baseplate and its function in triggering sheath contraction. Nature 2016; 533:346-52. [DOI: 10.1038/nature17971] [Citation(s) in RCA: 181] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 04/05/2016] [Indexed: 12/12/2022]
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26
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Oikonomou CM, Chang YW, Jensen GJ. A new view into prokaryotic cell biology from electron cryotomography. Nat Rev Microbiol 2016; 14:205-20. [PMID: 26923112 PMCID: PMC5551487 DOI: 10.1038/nrmicro.2016.7] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Electron cryotomography (ECT) enables intact cells to be visualized in 3D in an essentially native state to 'macromolecular' (∼4 nm) resolution, revealing the basic architectures of complete nanomachines and their arrangements in situ. Since its inception, ECT has advanced our understanding of many aspects of prokaryotic cell biology, from morphogenesis to subcellular compartmentalization and from metabolism to complex interspecies interactions. In this Review, we highlight how ECT has provided structural and mechanistic insights into the physiology of bacteria and archaea and discuss prospects for the future.
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Affiliation(s)
- Catherine M Oikonomou
- Howard Hughes Medical Institute; Division of Biology and Biological Engineering, California Institute of Technology, 1200 E. California Blvd., Pasadena, California 91125, USA
| | - Yi-Wei Chang
- Howard Hughes Medical Institute; Division of Biology and Biological Engineering, California Institute of Technology, 1200 E. California Blvd., Pasadena, California 91125, USA
| | - Grant J Jensen
- Howard Hughes Medical Institute; Division of Biology and Biological Engineering, California Institute of Technology, 1200 E. California Blvd., Pasadena, California 91125, USA
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27
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Abstract
Cryo-electron tomography (cryo-ET) has emerged as a leading technique for three-dimensional visualization of large macromolecular complexes and their conformational changes in their native cellular environment. However, the resolution and potential applications of cryo-ET are fundamentally limited by specimen thickness, preventing high-resolution in situ visualization of macromolecular structures in many bacteria (such as Escherichia coli and Salmonella enterica). Minicells, which were discovered nearly 50 years ago, have recently been exploited as model systems to visualize molecular machines in situ, due to their smaller size and other unique properties. In this review, we discuss strategies for producing minicells and highlight their use in the study of chemotactic signaling, protein secretion, and DNA translocation. In combination with powerful genetic tools and advanced imaging techniques, minicells provide a springboard for in-depth structural studies of bacterial macromolecular complexes in situ and therefore offer a unique approach for gaining novel structural insights into many important processes in microbiology.
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28
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Gold V, Kudryashev M. Recent progress in structure and dynamics of dual-membrane-spanning bacterial nanomachines. Curr Opin Struct Biol 2016; 39:1-7. [PMID: 26995496 DOI: 10.1016/j.sbi.2016.03.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 03/03/2016] [Accepted: 03/04/2016] [Indexed: 02/05/2023]
Abstract
Advances in hard-ware and soft-ware for electron cryo-microscopy and tomography have provided unprecedented structural insights into large protein complexes in bacterial membranes. Tomographic volumes of native complexes in situ, combined with other structural and functional data, reveal functionally important conformational changes. Here, we review recent progress in elucidating the structure and mechanism of dual-membrane-spanning nanomachines involved in bacterial motility, adhesion, pathogenesis and biofilm formation, including the type IV pilus assembly machinery and the type III and VI secretions systems. We highlight how these new structural data shed light on the assembly and action of such machines and discuss future directions for more detailed mechanistic understanding of these massive, fascinating complexes.
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Affiliation(s)
- Vicki Gold
- Department of Structural Biology, Max Planck Institute of Biophysics, Max-von-Laue Str. 3, 60438 Frankfurt am Main, Germany.
| | - Mikhail Kudryashev
- Max Planck Institute of Biophysics, Max-von-Laue Str. 3, 60438 Frankfurt am Main, Germany; Buchmann Institute for Molecular Life Sciences, Goethe University of Frankfurt, Max-von-Laue Str. 17, 60438 Frankfurt am Main, Germany.
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29
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Kennedy E, Nelson EM, Tanaka T, Damiano J, Timp G. Live Bacterial Physiology Visualized with 5 nm Resolution Using Scanning Transmission Electron Microscopy. ACS NANO 2016; 10:2669-2677. [PMID: 26811950 DOI: 10.1021/acsnano.5b07697] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
It is now possible to visualize at nanometer resolution the infection of a living biological cell with virus without compromising cell viability using scanning transmission electron microscopy (STEM). To provide contrast while preserving viability, Escherichia coli and P1 bacteriophages were first positively stained with a very low concentration of uranyl acetate in minimal phosphate medium and then imaged with low-dose STEM in a microfluidic liquid flow cell. Under these conditions, it was established that the median lethal dose of electrons required to kill half the tested population was LD50 = 30 e(-)/nm(2), which coincides with the disruption of a wet biological membrane, according to prior reports. Consistent with the lateral resolution and high-contrast signal-to-noise ratio (SNR) inferred from Monte Carlo simulations, images of the E. coli membrane, flagella, and the bacteriophages were acquired with 5 nm resolution, but the cumulative dose exceeded LD50. On the other hand, with a cumulative dose below LD50 (and lower SNR), it was still possible to visualize the infection of E. coli by P1, showing the insertion of viral DNA within 3 s, with 5 nm resolution.
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Affiliation(s)
| | | | | | - John Damiano
- Protochips, Inc. , Morrisville, North Carolina 27560, United States
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30
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Structural remodeling of bacteriophage T4 and host membranes during infection initiation. Proc Natl Acad Sci U S A 2015; 112:E4919-28. [PMID: 26283379 DOI: 10.1073/pnas.1501064112] [Citation(s) in RCA: 143] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The first stages of productive bacteriophage infections of bacterial host cells require efficient adsorption to the cell surface followed by ejection of phage DNA into the host cytoplasm. To achieve this goal, a phage virion must undergo significant structural remodeling. For phage T4, the most obvious change is the contraction of its tail. Here, we use skinny E. coli minicells as a host, along with cryo-electron tomography and mutant phage virions, to visualize key structural intermediates during initiation of T4 infection. We show for the first time that most long tail fibers are folded back against the tail sheath until irreversible adsorption, a feature compatible with the virion randomly walking across the cell surface to find an optimal site for infection. Our data confirm that tail contraction is triggered by structural changes in the baseplate, as intermediates were found with remodeled baseplates and extended tails. After contraction, the tail tube penetrates the host cell periplasm, pausing while it degrades the peptidoglycan layer. Penetration into the host cytoplasm is accompanied by a dramatic local outward curvature of the cytoplasmic membrane as it fuses with the phage tail tip. The baseplate hub protein gp27 and/or the ejected tape measure protein gp29 likely form the transmembrane channel for viral DNA passage into the cell cytoplasm. Building on the wealth of prior biochemical and structural information, this work provides new molecular insights into the mechanistic pathway of T4 phage infection.
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31
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Characterization of a P1-like bacteriophage carrying an SHV-2 extended-spectrum β-lactamase from an Escherichia coli strain. Antimicrob Agents Chemother 2014; 58:6550-7. [PMID: 25136025 DOI: 10.1128/aac.03183-14] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
P1 bacteriophages lysogenize bacteria as independent plasmid-like elements. We describe here a P1-like bacteriophage, RCS47, carrying a blaSHV-2 gene, isolated from a clinical strain of Escherichia coli from phylogroup B1, and we report the prevalence of P1-like prophages in natural E. coli isolates. We found that 70% of the sequence of RCS47, a 115-kb circular molecule, was common to the reference P1 bacteriophage under GenBank accession no. AF234172.1, with the shared sequences being 99% identical. RCS47 had acquired two main foreign DNA fragments: a 9,636-bp fragment mobilized by two IS26 elements containing a blaSHV-2 gene, and an 8,544-bp fragment mobilized by two IS5 elements containing an operon encoding a dimethyl sulfoxide reductase. The reference P1 prophage plasmid replication gene belonged to the IncY incompatibility group, whereas that of RCS47 was from an unknown group. The lytic capacity of RCS47 and blaSHV-2 gene transduction, through the lysogenization of RCS47 in the recipient E. coli strains, were not demonstrated. The prevalence of P1-like prophages in various animal and human E. coli strain collections, as determined by the PCR detection of repL, the lytic replication gene, was 12.6%. No differences in the prevalences of these prophages were found between extended-spectrum β-lactamase (ESBL)-producing and non-ESBL-producing strains (P = 0.69), but this prevalence was lower in phylogroup B2 than in the other phylogroups (P = 0.008), suggesting epistatic interactions between P1 family phages and the genetic background of E. coli strains. P1-like phages are part of the mobile elements that carry antibiotic resistance. The high prevalence of P1-like prophages suggests their role may be underestimated.
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32
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Abstract
![]()
The flagellum is one of the most
sophisticated self-assembling
molecular machines in bacteria. Powered by the proton-motive force,
the flagellum rapidly rotates in either a clockwise or counterclockwise
direction, which ultimately controls bacterial motility and behavior. Escherichia coli and Salmonella enterica have served as important model systems for extensive genetic, biochemical,
and structural analysis of the flagellum, providing unparalleled insights
into its structure, function, and gene regulation. Despite these advances,
our understanding of flagellar assembly and rotational mechanisms
remains incomplete, in part because of the limited structural information
available regarding the intact rotor–stator complex and secretion
apparatus. Cryo-electron tomography (cryo-ET) has become a valuable
imaging technique capable of visualizing the intact flagellar motor
in cells at molecular resolution. Because the resolution that can
be achieved by cryo-ET with large bacteria (such as E. coli and S. enterica) is limited, analysis of small-diameter
bacteria (including Borrelia burgdorferi and Campylobacter jejuni) can provide additional insights into
the in situ structure of the flagellar motor and
other cellular components. This review is focused on the application
of cryo-ET, in combination with genetic and biophysical approaches,
to the study of flagellar structures and its potential for improving
the understanding of rotor–stator interactions, the rotational
switching mechanism, and the secretion and assembly of flagellar components.
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Affiliation(s)
- Xiaowei Zhao
- Department of Pathology and Laboratory Medicine, University of Texas Medical School at Houston , Houston, Texas 77030, United States
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33
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Leavitt JC, Gogokhia L, Gilcrease EB, Bhardwaj A, Cingolani G, Casjens SR. The tip of the tail needle affects the rate of DNA delivery by bacteriophage P22. PLoS One 2013; 8:e70936. [PMID: 23951045 PMCID: PMC3741392 DOI: 10.1371/journal.pone.0070936] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 06/25/2013] [Indexed: 02/01/2023] Open
Abstract
The P22-like bacteriophages have short tails. Their virions bind to their polysaccharide receptors through six trimeric tailspike proteins that surround the tail tip. These short tails also have a trimeric needle protein that extends beyond the tailspikes from the center of the tail tip, in a position that suggests that it should make first contact with the host’s outer membrane during the infection process. The base of the needle serves as a plug that keeps the DNA in the virion, but role of the needle during adsorption and DNA injection is not well understood. Among the P22-like phages are needle types with two completely different C-terminal distal tip domains. In the phage Sf6-type needle, unlike the other P22-type needle, the distal tip folds into a “knob” with a TNF-like fold, similar to the fiber knobs of bacteriophage PRD1 and Adenovirus. The phage HS1 knob is very similar to that of Sf6, and we report here its crystal structure which, like the Sf6 knob, contains three bound L-glutamate molecules. A chimeric P22 phage with a tail needle that contains the HS1 terminal knob efficiently infects the P22 host, Salmonella enterica, suggesting the knob does not confer host specificity. Likewise, mutations that should abrogate the binding of L-glutamate to the needle do not appear to affect virion function, but several different other genetic changes to the tip of the needle slow down potassium release from the host during infection. These findings suggest that the needle plays a role in phage P22 DNA delivery by controlling the kinetics of DNA ejection into the host.
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Affiliation(s)
- Justin C. Leavitt
- Biology Department, University of Utah, Salt Lake City, Utah, United States of America
| | - Lasha Gogokhia
- Division of Microbiology and Immunology, Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Eddie B. Gilcrease
- Division of Microbiology and Immunology, Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Anshul Bhardwaj
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania, United States of America
| | - Gino Cingolani
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania, United States of America
| | - Sherwood R. Casjens
- Biology Department, University of Utah, Salt Lake City, Utah, United States of America
- Division of Microbiology and Immunology, Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- * E-mail:
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34
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Kudryashev M, Stenta M, Schmelz S, Amstutz M, Wiesand U, Castaño-Díez D, Degiacomi MT, Münnich S, Bleck CK, Kowal J, Diepold A, Heinz DW, Dal Peraro M, Cornelis GR, Stahlberg H. In situ structural analysis of the Yersinia enterocolitica injectisome. eLife 2013; 2:e00792. [PMID: 23908767 PMCID: PMC3728920 DOI: 10.7554/elife.00792] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Accepted: 06/27/2013] [Indexed: 12/20/2022] Open
Abstract
Injectisomes are multi-protein transmembrane machines allowing pathogenic bacteria to
inject effector proteins into eukaryotic host cells, a process called type III
secretion. Here we present the first three-dimensional structure of Yersinia
enterocolitica and Shigella flexneri injectisomes in
situ and the first structural analysis of the Yersinia injectisome.
Unexpectedly, basal bodies of injectisomes inside the bacterial cells showed length
variations of 20%. The in situ structures of the Y. enterocolitica
and S. flexneri injectisomes had similar dimensions and were
significantly longer than the isolated structures of related injectisomes. The
crystal structure of the inner membrane injectisome component YscD appeared elongated
compared to a homologous protein, and molecular dynamics simulations documented its
elongation elasticity. The ring-shaped secretin YscC at the outer membrane was
stretched by 30–40% in situ, compared to its isolated liposome-embedded
conformation. We suggest that elasticity is critical for some two-membrane spanning
protein complexes to cope with variations in the intermembrane distance. DOI:http://dx.doi.org/10.7554/eLife.00792.001 Humans and other animals can use the five senses—touch, taste, sight, smell,
and hearing—to interpret the world around them. Single-celled organisms,
however, must rely on molecular cues to understand their immediate surroundings. In
particular, bacteria gather information about external conditions, including
potential hosts nearby, by secreting protein sensors that can relay messages back to
the cell. Bacteria export these sensors via secretion systems that enable the organism both to
receive information about the environment and to invade a host cell. A total of seven
separate secretion systems, known as types I–VII, have been identified. These
different secretion systems handle distinct cargoes, allowing the bacterial cell to
respond to a range of feedback from the external milieu. The type III secretion system, also known as the ‘injectisome’, is
found in bacterial species that are enclosed by two membranes separated by a
periplasmic space. The injectisome comprises different components that combine to
form the basal body, which spans the inner and outer membranes, and a projection from
the basal body, called the hollow needle, that mediates the export of cargo from a
bacterium to its host or the local environment. The distance between the inner and outer membranes may vary across species or
according to environmental conditions, so the basal body must be able to accommodate
these changes. However, no mechanism has yet been established that might introduce
such elasticity into the injectisome. Now, Kudryashev et al. have generated
three-dimensional structures for the injectisomes of two species of bacteria,
Shigella flexneri and Yersinia enterocolitica,
and shown that the size of the basal body can fluctuate by up to 20%. Kudryashev et al. imaged whole injectisomes in these two species and found that the
height of the basal body was proportional to the distance between the inner and outer
membranes. To probe how this could occur, the properties of two proteins that are
important components of the basal body were studied in greater detail. YscD, a
protein that extends across the periplasmic space, was crystallized and its structure
was then determined and used to develop a computer model to assess its
compressibility: this model indicated that YscD could stretch or contract by up to
50% of its total length. The outer membrane component YscC also appeared elastic:
when the protein was isolated and introduced into synthetic membranes, its length was
reduced 30–40% relative to that observed in intact bacterial membranes. A further experiment confirmed the adaptability of the basal body: when the
separation of the membranes was deliberately increased by placing bacteria in a
high-salt medium, the basal body extended approximately 10% in length. Cumulatively,
therefore, these experiments suggest that the in-built flexibility of the basal body
of the injectisome allows bacteria to adjust to environmental changes while
maintaining their sensory abilities and host-invasion potential. DOI:http://dx.doi.org/10.7554/eLife.00792.002
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Affiliation(s)
- Mikhail Kudryashev
- Center for Cellular Imaging and NanoAnalytics (C-CINA) , Biozentrum, University of Basel , Basel , Switzerland
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35
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Single particle and molecular assembly analysis of polyribosomes by single- and double-tilt cryo electron tomography. Ultramicroscopy 2013; 126:33-9. [DOI: 10.1016/j.ultramic.2012.12.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Revised: 11/27/2012] [Accepted: 12/07/2012] [Indexed: 11/19/2022]
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36
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Leforestier A. Polymorphism of DNA conformation inside the bacteriophage capsid. J Biol Phys 2013; 39:201-13. [PMID: 23860869 PMCID: PMC3662419 DOI: 10.1007/s10867-013-9315-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Accepted: 03/20/2013] [Indexed: 10/27/2022] Open
Abstract
Double-stranded DNA bacteriophage genomes are packaged into their icosahedral capsids at the highest densities known so far (about 50 % w:v). How the molecule is folded at such density and how its conformation changes upon ejection or packaging are fascinating questions still largely open. We review cryo-TEM analyses of DNA conformation inside partially filled capsids as a function of the physico-chemical environment (ions, osmotic pressure, temperature). We show that there exists a wide variety of DNA conformations. Strikingly, the different observed structures can be described by some of the different models proposed over the years for DNA organisation inside bacteriophage capsids: either spool-like structures with axial or concentric symmetries, or liquid crystalline structures characterised by a DNA homogeneous density. The relevance of these conformations for the understanding of DNA folding and unfolding upon ejection and packaging in vivo is discussed.
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Affiliation(s)
- Amélie Leforestier
- Laboratoire de Physqiue des Solides, CNRS, UMR 8502, Université Paris Sud, Orsay, France.
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Guerrero-Ferreira RC, Wright ER. Cryo-electron tomography of bacterial viruses. Virology 2013; 435:179-86. [PMID: 23217626 DOI: 10.1016/j.virol.2012.08.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Revised: 08/08/2012] [Accepted: 08/19/2012] [Indexed: 01/15/2023]
Abstract
Bacteriophage particles contain both simple and complex macromolecular assemblages and machines that enable them to regulate the infection process under diverse environmental conditions with a broad range of bacterial hosts. Recent developments in cryo-electron tomography (cryo-ET) make it possible to observe the interactions of bacteriophages with their host cells under native-state conditions at unprecedented resolution and in three-dimensions. This review describes the application of cryo-ET to studies of bacteriophage attachment, genome ejection, assembly and egress. Current topics of investigation and future directions in the field are also discussed.
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Affiliation(s)
- Ricardo C Guerrero-Ferreira
- Division of Pediatric Infectious Diseases, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, GA 30322, USA
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Abstract
Sixty years after Hershey and Chase showed that nucleic acid is the major component of phage particles that is ejected into cells, we still do not fully understand how the process occurs. Advances in electron microscopy have revealed the structure of the condensed DNA confined in a phage capsid, and the mechanisms and energetics of packaging a phage genome are beginning to be better understood. Condensing DNA subjects it to high osmotic pressure, which has been suggested to provide the driving force for its ejection during infection. However, forces internal to a phage capsid cannot, alone, cause complete genome ejection into cells. Here, we describe the structure of the DNA inside mature phages and summarize the current models of genome ejection, both in vitro and in vivo.
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Affiliation(s)
- Ian J Molineux
- Molecular Genetics and Microbiology, Institute for Cell and Molecular Biology, The University of Texas at Austin, Austin, Texas 78712, USA.
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Shiomi D, Toyoda A, Aizu T, Ejima F, Fujiyama A, Shini T, Kohara Y, Niki H. Mutations in cell elongation genes mreB, mrdA and mrdB suppress the shape defect of RodZ-deficient cells. Mol Microbiol 2013; 87:1029-44. [PMID: 23301723 PMCID: PMC3599482 DOI: 10.1111/mmi.12148] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/28/2012] [Indexed: 11/30/2022]
Abstract
RodZ interacts with MreB and both factors are required to maintain the rod shape of Escherichia coli. The assembly of MreB into filaments regulates the subcellular arrangement of a group of enzymes that synthesizes the peptidoglycan (PG) layer. However, it is still unknown how polymerization of MreB determines the rod shape of bacterial cells. Regulatory factor(s) are likely to be involved in controlling the function and dynamics of MreB. We isolated suppressor mutations to partially recover the rod shape in rodZ deletion mutants and found that some of the suppressor mutations occurred in mreB. All of the mreB mutations were in or in the vicinity of domain IA of MreB. Those mreB mutations changed the property of MreB filaments in vivo. In addition, suppressor mutations were found in the periplasmic regions in PBP2 and RodA, encoded by mrdA and mrdB genes. Similar to MreB and RodZ, PBP2 and RodA are pivotal to the cell wall elongation process. Thus, we found that mutations in domain IA of MreB and in the periplasmic domain of PBP2 and RodA can restore growth and rod shape to ΔrodZ cells, possibly by changing the requirements of MreB in the process.
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Affiliation(s)
- Daisuke Shiomi
- Microbial Genetics Laboratory, Genetic Strains Research Center, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka 411-8540, Japan
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Hu B, Margolin W, Molineux IJ, Liu J. The bacteriophage t7 virion undergoes extensive structural remodeling during infection. Science 2013; 339:576-9. [PMID: 23306440 DOI: 10.1126/science.1231887] [Citation(s) in RCA: 162] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Adsorption and genome ejection are fundamental to the bacteriophage life cycle, yet their molecular mechanisms are not well understood. We used cryo-electron tomography to capture T7 virions at successive stages of infection of Escherichia coli minicells at ~4-nm resolution. The six phage tail fibers were folded against the capsid, extending and orienting symmetrically only after productive adsorption to the host cell surface. Receptor binding by the tail triggered conformational changes resulting in the insertion of an extended tail, which functions as the DNA ejection conduit into the cell cytoplasm. After ejection, the extended phage tail collapsed or disassembled, which allowed resealing of the infected cell membrane. These structural studies provide a detailed series of intermediates during phage infection.
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Affiliation(s)
- Bo Hu
- Department of Pathology and Laboratory Medicine, University of Texas Medical School at Houston, TX 77030, USA
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Abstract
Correct host cell recognition is important in the replication cycle for any virus, including bacterial viruses. This essential step should occur before the bacteriophage commits to transfer its genomic material into the host. In this chapter we will discuss the proteins and mechanisms bacteriophages use for receptor recognition (just before full commitment to infection) and nucleic acid injection, which occurs just after commitment. Some bacteriophages use proteins of the capsid proper for host cell recognition, others use specialised spikes or fibres. Usually, several identical recognition events take place, and the information that a suitable host cell has been encountered is somehow transferred to the part of the bacteriophage capsid involved in nucleic acid transfer. The main part of the capsids of bacteriophages stay on the cell surface after transferring their genome, although a few specialised proteins move with the DNA, either forming a conduit, protecting the nucleic acids after transfer and/or functioning in the process of transcription and translation.
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Affiliation(s)
- Carmela Garcia-Doval
- Department of Macromolecular Structure, Centro Nacional de Biotecnología (CSIC), c/Darwin 3, Campus de Cantoblanco, 28049, Madrid, Spain
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Molecular architecture of chemoreceptor arrays revealed by cryoelectron tomography of Escherichia coli minicells. Proc Natl Acad Sci U S A 2012; 109:E1481-8. [PMID: 22556268 DOI: 10.1073/pnas.1200781109] [Citation(s) in RCA: 150] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The chemoreceptors of Escherichia coli localize to the cell poles and form a highly ordered array in concert with the CheA kinase and the CheW coupling factor. However, a high-resolution structure of the array has been lacking, and the molecular basis of array assembly has thus remained elusive. Here, we use cryoelectron tomography of flagellated E. coli minicells to derive a 3D map of the intact array. Docking of high-resolution structures into the 3D map provides a model of the core signaling complex, in which a CheA/CheW dimer bridges two adjacent receptor trimers via multiple hydrophobic interactions. A further, hitherto unknown, hydrophobic interaction between CheW and the homologous P5 domain of CheA in an adjacent core complex connects the complexes into an extended array. This architecture provides a structural basis for array formation and could explain the high sensitivity and cooperativity of chemotaxis signaling in E. coli.
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Transmission electron microscopy studies of cellular responses to entry of virions: one kind of natural nanobiomaterial. Int J Cell Biol 2012; 2012:596589. [PMID: 22567012 PMCID: PMC3332201 DOI: 10.1155/2012/596589] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2011] [Accepted: 01/23/2012] [Indexed: 01/16/2023] Open
Abstract
Virions are one kind of nanoscale pathogen and are able to infect living cells of animals, plants, and bacteria. The infection is an intrinsic property of the virions, and the biological process provides a good model for studying how these nanoparticles enter into cells. During the infection, the viruses employ different strategies to which the cells have developed respective responses. For this paper, we chose Bombyx mori cypovirus 1 (BmCPV-1) interactions with midgut cells from silkworm, and severe acute respiratory syndrome (SARS) associated coronavirus interactions with Vero E6 cells, as examples to demonstrate the response of eukaryotic cells to two different types of virus from our previous studies. The bacteriophage-bacteria interactions are also introduced to elucidate how the bacteriophage conquers the barrier of cell walls in the prokaryotic cells to transport genome into the host.
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Phage Pierces the Host Cell Membrane with the Iron-Loaded Spike. Structure 2012; 20:326-39. [DOI: 10.1016/j.str.2011.12.009] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Revised: 12/02/2011] [Accepted: 12/04/2011] [Indexed: 11/23/2022]
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Role of channel lysines and the "push through a one-way valve" mechanism of the viral DNA packaging motor. Biophys J 2012; 102:127-35. [PMID: 22225806 PMCID: PMC3250684 DOI: 10.1016/j.bpj.2011.11.4013] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Revised: 10/27/2011] [Accepted: 11/14/2011] [Indexed: 11/22/2022] Open
Abstract
Linear double-stranded DNA (dsDNA) viruses package their genomes into preformed protein shells via nanomotors using ATP as an energy source. The central hub of the bacteriophage φ29 DNA-packaging motor contains a 3.6-nm channel for dsDNA to enter during packaging and to exit during infection. The negatively charged interior channel wall is decorated with a total of 48 positively charged lysine residues displayed as four 12-lysine rings from the 12 gp10 subunits that enclose the channel. The standard notion derived from many models is that these uniquely arranged, positively charged rings play active roles in DNA translocation through the channel. In this study, we tested this prevailing view by examining the effect of mutating these basic lysines to alanines, and assessing the impact of altering the pH environment. Unexpectedly, mutating these basic lysine residues or changing the pH to 4 or 10, which could alter the charge of lysines, did not measurably impair DNA translocation or affect the one-way traffic property of the channel. The results support our recent findings regarding the dsDNA packaging mechanism known as the "push through a one-way valve".
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