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Rascol E, Villette S, Harté E, Alves ID. Plasmon Waveguide Resonance: Principles, Applications and Historical Perspectives on Instrument Development. Molecules 2021; 26:molecules26216442. [PMID: 34770851 PMCID: PMC8588475 DOI: 10.3390/molecules26216442] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/15/2021] [Accepted: 10/20/2021] [Indexed: 11/16/2022] Open
Abstract
Plasmon waveguide resonance (PWR) is a variant of surface plasmon resonance (SPR) that was invented about two decades ago at the University of Arizona. In addition to the characterization of the kinetics and affinity of molecular interactions, PWR possesses several advantages relative to SPR, namely, the ability to monitor both mass and structural changes. PWR allows anisotropy information to be obtained and is ideal for the investigation of molecular interactions occurring in anisotropic-oriented thin films. In this review, we will revisit main PWR applications, aiming at characterizing molecular interactions occurring (1) at lipid membranes deposited in the sensor and (2) in chemically modified sensors. Among the most widely used applications is the investigation of G-protein coupled receptor (GPCR) ligand activation and the study of the lipid environment’s impact on this process. Pioneering PWR studies on GPCRs were carried out thanks to the strong and effective collaboration between two laboratories in the University of Arizona leaded by Dr. Gordon Tollin and Dr. Victor J. Hruby. This review provides an overview of the main applications of PWR and provides a historical perspective on the development of instruments since the first prototype and continuous technological improvements to ongoing and future developments, aiming at broadening the information obtained and expanding the application portfolio.
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Affiliation(s)
- Estelle Rascol
- Université de Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, F-33600 Pessac, France; (E.R.); (S.V.)
| | - Sandrine Villette
- Université de Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, F-33600 Pessac, France; (E.R.); (S.V.)
| | - Etienne Harté
- Université de Bordeaux and CNRS, LOMA, UMR 5798, F-33400 Talence, France;
| | - Isabel D. Alves
- Université de Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, F-33600 Pessac, France; (E.R.); (S.V.)
- Correspondence: ; Tel.: +33-5400-06-8949
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Phosphatidylinositol 3-Phosphate Mediates the Establishment of Infectious Bursal Disease Virus Replication Complexes in Association with Early Endosomes. J Virol 2021; 95:JVI.02313-20. [PMID: 33361427 DOI: 10.1128/jvi.02313-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 12/15/2020] [Indexed: 12/13/2022] Open
Abstract
Infectious bursal disease virus (IBDV) is the archetypal member of the family Birnaviridae and the etiological agent of Gumboro disease, a highly contagious immunosuppressive infection of concern to the global poultry sector for its adverse health effects in chicks. Unlike most double-stranded RNA (dsRNA) viruses, which enclose their genomes within specialized cores throughout their viral replication cycle, birnaviruses organize their bisegmented dsRNA genome in ribonucleoprotein (RNP) structures. Recently, we demonstrated that IBDV exploits endosomal membranes for replication. The establishment of IBDV replication machinery on the cytosolic leaflet of endosomal compartments is mediated by the viral protein VP3 and its intrinsic ability to target endosomes. In this study, we identified the early endosomal phosphatidylinositol 3-phosphate [PtdIns(3)P] as a key host factor of VP3 association with endosomal membranes and consequent establishment of IBDV replication complexes in early endosomes. Indeed, our data reveal a crucial role for PtdIns(3)P in IBDV replication. Overall, our findings provide new insights into the replicative strategy of birnaviruses and strongly suggest that it resembles those of positive-strand RNA (+ssRNA) viruses, which replicate in association with host membranes. Furthermore, our findings support the role of birnaviruses as evolutionary intermediaries between +ssRNA and dsRNA viruses and, importantly, demonstrate a novel role for PtdIns(3)P in the replication of a dsRNA virus.IMPORTANCE Infectious bursal disease virus (IBDV) infects chicks and is the causative agent of Gumboro disease. During IBDV outbreaks in recent decades, the emergence of very virulent variants and the lack of effective prevention/treatment strategies to fight this disease have had devastating consequences for the poultry industry. IBDV belongs to the peculiar family Birnaviridae Unlike most dsRNA viruses, birnaviruses organize their genomes in ribonucleoprotein complexes and replicate in a core-independent manner. We recently demonstrated that IBDV exploits host cell endosomes as platforms for viral replication, a process that depends on the VP3 viral protein. In this study, we delved deeper into the molecular characterization of IBDV-endosome association and investigated the role of host cell phosphatidylinositide lipids in VP3 protein localization and IBDV infection. Together, our findings demonstrate that PtdIns(3)P serves as a scaffold for the association of VP3 to endosomes and reveal its essential role for IBDV replication.
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The RNA-Binding Protein of a Double-Stranded RNA Virus Acts like a Scaffold Protein. J Virol 2018; 92:JVI.00968-18. [PMID: 30021893 DOI: 10.1128/jvi.00968-18] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2018] [Accepted: 07/09/2018] [Indexed: 12/22/2022] Open
Abstract
Infectious bursal disease virus (IBDV), a nonenveloped, double-stranded RNA (dsRNA) virus with a T=13 icosahedral capsid, has a virion assembly strategy that initiates with a precursor particle based on an internal scaffold shell similar to that of tailed double-stranded DNA (dsDNA) viruses. In IBDV-infected cells, the assembly pathway results mainly in mature virions that package four dsRNA segments, although minor viral populations ranging from zero to three dsRNA segments also form. We used cryo-electron microscopy (cryo-EM), cryo-electron tomography, and atomic force microscopy to characterize these IBDV populations. The VP3 protein was found to act as a scaffold protein by building an irregular, ∼40-Å-thick internal shell without icosahedral symmetry, which facilitates formation of a precursor particle, the procapsid. Analysis of IBDV procapsid mechanical properties indicated a VP3 layer beneath the icosahedral shell, which increased the effective capsid thickness. Whereas scaffolding proteins are discharged in tailed dsDNA viruses, VP3 is a multifunctional protein. In mature virions, VP3 is bound to the dsRNA genome, which is organized as ribonucleoprotein complexes. IBDV is an amalgam of dsRNA viral ancestors and traits from dsDNA and single-stranded RNA (ssRNA) viruses.IMPORTANCE Structural analyses highlight the constraint of virus evolution to a limited number of capsid protein folds and assembly strategies that result in a functional virion. We report the cryo-EM and cryo-electron tomography structures and the results of atomic force microscopy studies of the infectious bursal disease virus (IBDV), a double-stranded RNA virus with an icosahedral capsid. We found evidence of a new inner shell that might act as an internal scaffold during IBDV assembly. The use of an internal scaffold is reminiscent of tailed dsDNA viruses, which constitute the most successful self-replicating system on Earth. The IBDV scaffold protein is multifunctional and, after capsid maturation, is genome bound to form ribonucleoprotein complexes. IBDV encompasses numerous functional and structural characteristics of RNA and DNA viruses; we suggest that IBDV is a modern descendant of ancestral viruses and comprises different features of current viral lineages.
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Falanga A, Galdiero M, Morelli G, Galdiero S. Membranotropic peptides mediating viral entry. Pept Sci (Hoboken) 2018; 110:e24040. [PMID: 32328541 PMCID: PMC7167733 DOI: 10.1002/pep2.24040] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 11/27/2017] [Accepted: 12/20/2017] [Indexed: 02/06/2023]
Abstract
The means used by enveloped viruses to bypass cellular membranes are well characterized; however, the mechanisms used by non-enveloped viruses to deliver their genome inside the cell remain unresolved and poorly defined. The discovery of short, membrane interacting, amphipathic or hydrophobic sequences (known as membranotropic peptides) in both enveloped and non-enveloped viruses suggests that these small peptides are strongly involved in breaching the host membrane and in the delivery of the viral genome into the host cell. Thus, in spite of noticeable differences in entry, this short stretches of membranotropic peptides are probably associated with similar entry-related events. This review will uncover the intrinsic features of viral membranotropic peptides involved in viral entry of both naked viruses and the ones encircled with a biological membrane with the objective to better elucidate their different functional properties and possible applications in the biomedical field.
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Affiliation(s)
- Annarita Falanga
- Department of Pharmacy, School of MedicineNaples80134Italy
- CIRPEB University of Naples Federico II, Via Mezzocannone 16Naples80134Italy
| | - Massimiliano Galdiero
- CIRPEB University of Naples Federico II, Via Mezzocannone 16Naples80134Italy
- Department of Experimental MedicineUniversity of Campania “Luigi Vanvitelli,” Via de CrecchioNaples80134Italy
| | - Giancarlo Morelli
- Department of Pharmacy, School of MedicineNaples80134Italy
- CIRPEB University of Naples Federico II, Via Mezzocannone 16Naples80134Italy
| | - Stefania Galdiero
- Department of Pharmacy, School of MedicineNaples80134Italy
- CIRPEB University of Naples Federico II, Via Mezzocannone 16Naples80134Italy
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Xu J, Gui M, Wang D, Xiang Y. The bacteriophage ϕ29 tail possesses a pore-forming loop for cell membrane penetration. Nature 2016; 534:544-7. [PMID: 27309813 DOI: 10.1038/nature18017] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Accepted: 04/14/2016] [Indexed: 12/29/2022]
Abstract
Most bacteriophages are tailed bacteriophages with an isometric or a prolate head attached to a long contractile, long non-contractile, or short non-contractile tail. The tail is a complex machine that plays a central role in host cell recognition and attachment, cell wall and membrane penetration, and viral genome ejection. The mechanisms involved in the penetration of the inner host cell membrane by bacteriophage tails are not well understood. Here we describe structural and functional studies of the bacteriophage ϕ29 tail knob protein gene product 9 (gp9). The 2.0 Å crystal structure of gp9 shows that six gp9 molecules form a hexameric tube structure with six flexible hydrophobic loops blocking one end of the tube before DNA ejection. Sequence and structural analyses suggest that the loops in the tube could be membrane active. Further biochemical assays and electron microscopy structural analyses show that the six hydrophobic loops in the tube exit upon DNA ejection and form a channel that spans the lipid bilayer of the membrane and allows the release of the bacteriophage genomic DNA, suggesting that cell membrane penetration involves a pore-forming mechanism similar to that of certain non-enveloped eukaryotic viruses. A search of other phage tail proteins identified similar hydrophobic loops, which indicates that a common mechanism might be used for membrane penetration by prokaryotic viruses. These findings suggest that although prokaryotic and eukaryotic viruses use apparently very different mechanisms for infection, they have evolved similar mechanisms for breaching the cell membrane.
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Affiliation(s)
- Jingwei Xu
- Centre for Infectious Diseases Research, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing Advanced Innovation Center for Structural Biology, Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Miao Gui
- Centre for Infectious Diseases Research, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing Advanced Innovation Center for Structural Biology, Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Dianhong Wang
- Centre for Infectious Diseases Research, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing Advanced Innovation Center for Structural Biology, Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Ye Xiang
- Centre for Infectious Diseases Research, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing Advanced Innovation Center for Structural Biology, Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
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Three-dimensional structure of a protozoal double-stranded RNA virus that infects the enteric pathogen Giardia lamblia. J Virol 2014; 89:1182-94. [PMID: 25378500 DOI: 10.1128/jvi.02745-14] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
UNLABELLED Giardia lamblia virus (GLV) is a small, nonenveloped, nonsegmented double-stranded RNA (dsRNA) virus infecting Giardia lamblia, the most common protozoan pathogen of the human intestine and a major agent of waterborne diarrheal disease worldwide. GLV (genus Giardiavirus) is a member of family Totiviridae, along with several other groups of protozoal or fungal viruses, including Leishmania RNA viruses and Trichomonas vaginalis viruses. Interestingly, GLV is more closely related than other Totiviridae members to a group of recently discovered metazoan viruses that includes penaeid shrimp infectious myonecrosis virus (IMNV). Moreover, GLV is the only known protozoal dsRNA virus that can transmit efficiently by extracellular means, also like IMNV. In this study, we used transmission electron cryomicroscopy and icosahedral image reconstruction to examine the GLV virion at an estimated resolution of 6.0 Å. Its outermost diameter is 485 Å, making it the largest totivirus capsid analyzed to date. Structural comparisons of GLV and other totiviruses highlighted a related "T=2" capsid organization and a conserved helix-rich fold in the capsid subunits. In agreement with its unique capacity as a protozoal dsRNA virus to survive and transmit through extracellular environments, GLV was found to be more thermoresistant than Trichomonas vaginalis virus 1, but no specific protein machinery to mediate cell entry, such as the fiber complexes in IMNV, could be localized. These and other structural and biochemical findings provide a basis for future work to dissect the cell entry mechanism of GLV into a "primitive" (early-branching) eukaryotic host and an important enteric pathogen of humans. IMPORTANCE Numerous pathogenic bacteria, including Corynebacterium diphtheriae, Salmonella enterica, and Vibrio cholerae, are infected with lysogenic bacteriophages that contribute significantly to bacterial virulence. In line with this phenomenon, several pathogenic protozoa, including Giardia lamblia, Leishmania species, and Trichomonas vaginalis are persistently infected with dsRNA viruses, and growing evidence indicates that at least some of these protozoal viruses can likewise enhance the pathogenicity of their hosts. Understanding of these protozoal viruses, however, lags far behind that of many bacteriophages. Here, we investigated the dsRNA virus that infects the widespread enteric parasite Giardia lamblia. Using electron cryomicroscopy and icosahedral image reconstruction, we determined the virion structure of Giardia lamblia virus, obtaining new information relating to its assembly, stability, functions in cell entry and transcription, and similarities and differences with other dsRNA viruses. The results of our study set the stage for further mechanistic work on the roles of these viruses in protozoal virulence.
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Elaid S, Libersou S, Ouldali M, Morellet N, Desbat B, Alves ID, Lepault J, Bouaziz S. A peptide derived from the rotavirus outer capsid protein VP7 permeabilizes artificial membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1838:2026-35. [DOI: 10.1016/j.bbamem.2014.04.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Revised: 04/02/2014] [Accepted: 04/07/2014] [Indexed: 01/02/2023]
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Galdiero S, Falanga A, Vitiello M, Grieco P, Caraglia M, Morelli G, Galdiero M. Exploitation of viral properties for intracellular delivery. J Pept Sci 2014; 20:468-78. [PMID: 24889153 PMCID: PMC7168031 DOI: 10.1002/psc.2649] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 04/16/2014] [Accepted: 04/18/2014] [Indexed: 01/23/2023]
Abstract
Nanotechnology is an expanding area of study with potentially pivotal applications in a discipline as medicine where new biomedical active molecules or strategies are continuously developing. One of the principal drawbacks for the application of new therapies is the difficulty to cross membranes that represent the main physiological barrier in our body and in all living cells. Membranes are selectively permeable and allow the selective internalization of substances; generally, they form a highly impermeable barrier to most polar and charged molecules, and represent an obstacle for drug delivery, limiting absorption to specific routes and mechanisms. Viruses provide attracting suggestions for the development of targeted drug carriers as they have evolved naturally to deliver their genomes to host cells with high fidelity. A detailed understanding of virus structure and their mechanisms of entry into mammalian cells will facilitate the development and analysis of virus‐based materials for medical applications. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.
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Affiliation(s)
- Stefania Galdiero
- Department of Pharmacy, University of Naples "Federico II", Via Mezzocannone 16, and Via Domenico Montesano 49, 80100, Napoli, Italy; Centro Interuniversitario di Ricerca sui Peptidi Bioattivi, University of Naples "Federico II", Via Mezzocannone 16, 80134, Napoli, Italy; Istituto di Biostrutture e Bioimmagini - CNR, Via Mezzocannone 16, 80134, Napoli, Italy; DFM Scarl, Via Mezzocannone 16, 80134, Napoli, Italy
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Peptide-lipid interactions: experiments and applications. Int J Mol Sci 2013; 14:18758-89. [PMID: 24036440 PMCID: PMC3794806 DOI: 10.3390/ijms140918758] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 08/27/2013] [Accepted: 08/28/2013] [Indexed: 02/06/2023] Open
Abstract
The interactions between peptides and lipids are of fundamental importance in the functioning of numerous membrane-mediated cellular processes including antimicrobial peptide action, hormone-receptor interactions, drug bioavailability across the blood-brain barrier and viral fusion processes. Moreover, a major goal of modern biotechnology is obtaining new potent pharmaceutical agents whose biological action is dependent on the binding of peptides to lipid-bilayers. Several issues need to be addressed such as secondary structure, orientation, oligomerization and localization inside the membrane. At the same time, the structural effects which the peptides cause on the lipid bilayer are important for the interactions and need to be elucidated. The structural characterization of membrane active peptides in membranes is a harsh experimental challenge. It is in fact accepted that no single experimental technique can give a complete structural picture of the interaction, but rather a combination of different techniques is necessary.
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Gomes-Neto F, Valente AP, Almeida FCL. Modeling the interaction of dodecylphosphocholine micelles with the anticoccidial peptide PW2 guided by NMR data. Molecules 2013; 18:10056-80. [PMID: 23966088 PMCID: PMC6270265 DOI: 10.3390/molecules180810056] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 08/05/2013] [Accepted: 08/07/2013] [Indexed: 11/16/2022] Open
Abstract
Antimicrobial peptides are highly dynamic entities that acquire structure upon binding to a membrane interface. To better understand the structure and the mechanism for the molecular recognition of dodecylphosphocholine (DPC) micelles by the anticoccidial peptide PW2, we performed molecular dynamics (MD) simulations guided by NMR experimental data, focusing on strategies to explore the transient nature of micelles, which rearrange on a millisecond to second timescale. We simulated the association of PW2 with a pre-built DPC micelle and with free-DPC molecules that spontaneously forms micelles in the presence of the peptide along the simulation. The simulation with spontaneous micelle formation provided the adequate environment which replicated the experimental data. The unrestrained MD simulations reproduced the NMR structure for the entire 100 ns MD simulation time. Hidden discrete conformational states could be described. Coulomb interactions are important for initial approximation and hydrogen bonds for floating the aromatic region at the interface, being essential for the stabilization of the interaction. Arg9 is strongly attached with phosphate. We observed a helix elongation process stabilized by the intermolecular peptide-micelle association. Full association that mimics the experimental data only happens after complete micelle re-association. Fast micelle dynamics without dissociation of surfactants leads to only superficial binding.
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Affiliation(s)
- Francisco Gomes-Neto
- Laboratory of Toxinology, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro 21045-900, Brazil; E-Mail:
- Institute of Medical Biochemistry, National Center of Nuclear Magnetic Resonance Jiri Jonas, Federal University of Rio de Janeiro - Institute of Structural Biology and Bioimaging, Rio de Janeiro 21941-920, Brazil; E-Mail:
| | - Ana Paula Valente
- Institute of Medical Biochemistry, National Center of Nuclear Magnetic Resonance Jiri Jonas, Federal University of Rio de Janeiro - Institute of Structural Biology and Bioimaging, Rio de Janeiro 21941-920, Brazil; E-Mail:
| | - Fabio C. L. Almeida
- Institute of Medical Biochemistry, National Center of Nuclear Magnetic Resonance Jiri Jonas, Federal University of Rio de Janeiro - Institute of Structural Biology and Bioimaging, Rio de Janeiro 21941-920, Brazil; E-Mail:
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +55-21-3104-2326; Fax: +55-21-3104-2326
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Domitrovic T, Matsui T, Johnson JE. Dissecting quasi-equivalence in nonenveloped viruses: membrane disruption is promoted by lytic peptides released from subunit pentamers, not hexamers. J Virol 2012; 86:9976-82. [PMID: 22761380 PMCID: PMC3446560 DOI: 10.1128/jvi.01089-12] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Accepted: 06/28/2012] [Indexed: 11/20/2022] Open
Abstract
Nonenveloped viruses often invade membranes by exposing hydrophobic or amphipathic peptides generated by a proteolytic maturation step that leaves a lytic peptide noncovalently associated with the viral capsid. Since multiple copies of the same protein form many nonenveloped virus capsids, it is unclear if lytic peptides derived from subunits occupying different positions in a quasi-equivalent icosahedral capsid play different roles in host infection. We addressed this question with Nudaurelia capensis omega virus (NωV), an insect RNA virus with an icosahedral capsid formed by protein α, which undergoes autocleavage during maturation, producing the lytic γ peptide. NωV is a unique model because autocatalysis can be precisely initiated in vitro and is sufficiently slow to correlate lytic activity with γ peptide production. Using liposome-based assays, we observed that autocatalysis is essential for the potent membrane disruption caused by NωV. We observed that lytic activity is acquired rapidly during the maturation program, reaching 100% activity with less than 50% of the subunits cleaved. Previous time-resolved structural studies of partially mature NωV particles showed that, during this time frame, γ peptides derived from the pentamer subunits are produced and are organized in a vertical helical bundle that is projected toward the particle surface, while identical polypeptides in quasi-equivalent subunits are produced later or are in positions inappropriate for release. Our functional data provide experimental support for the hypothesis that pentamers containing a central helical bundle, observed in different nonenveloped virus families, are a specialized lytic motif.
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Affiliation(s)
- Tatiana Domitrovic
- Department of Molecular Biology, The Scripps Research Institute, La Jolla California, USA
| | - Tsutomu Matsui
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, California, USA
| | - John E. Johnson
- Department of Molecular Biology, The Scripps Research Institute, La Jolla California, USA
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Jofré C, Guzmán F, Cárdenas C, Albericio F, Marshall SH. A natural peptide and its variants derived from the processing of infectious pancreatic necrosis virus (IPNV) displaying enhanced antimicrobial activity: a novel alternative for the control of bacterial diseases. Peptides 2011; 32:852-8. [PMID: 21291934 DOI: 10.1016/j.peptides.2011.01.026] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Revised: 01/20/2011] [Accepted: 01/20/2011] [Indexed: 11/24/2022]
Abstract
The larger segment of the infectious pancreatic necrosis virus (IPNV) codifies most of the structural and non-structural proteins of the virus in two overlapping open reading frames (ORFs). The longer of the two ORF is expressed as a polyprotein which generates a number of variable length peptides of unknown function during processing. Since an appealing hypothesis would be that these peptides are generated by the virus to act as antimicrobial agents that favor viral infectivity in their fish host, we decided to test this possibility by selecting a master peptide and using it to generate substitution variants that may enhance their antimicrobial potential. A 20-residue master peptide (p20) was selected from the well-described maturation process of the structural viral protein VP2; several variants were then designed and chemically synthesized, ranging in size from 16 to 20 residues. The synthesized peptides were tested for in vitro activity against several prototype bacterial pathogens using standardized laboratory procedures. Chemically synthesized p20 and all its variants displayed broad activity against the tested bacteria and none of them were toxic to eukaryotic cells at least 10× the concentration used against the bacteria. Interestingly, when p20 was tested against the very aggressive bacterial pathogen Piscirickettsia salmonis, a common co-infectant of IPNV in salmonid fish, the specific activity of the novel peptide was significantly higher than that displayed for bactericidal fish farm antibiotics such as oxolinic acid, flumequine and florfenicol, which are commonly used to control Piscirickettsiosis in the field. It is potentially significant that the approach presented in this report provides a novel alternative for generating new and ideally more efficient and friendly safeguards for bacterial prophylaxis.
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Affiliation(s)
- Claudio Jofré
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Campus Curauma, Av Parque Sur, Valparaíso, Chile.
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