Search results for "virions"
showing 6 items of 6 documents
The role of spatial structure in the evolution of viral innate immunity evasion: A diffusion-reaction cellular automaton model
2020
Most viruses have evolved strategies for preventing interferon (IFN) secretion and evading innate immunity. Recent work has shown that viral shutdown of IFN secretion can be viewed as a social trait, since the ability of a given virus to evade IFN-mediated immunity depends on the phenotype of neighbor viruses. Following this idea, we investigate the role of spatial structure in the evolution of innate immunity evasion. For this, we model IFN signaling and viral spread using a spatially explicit approximation that combines a diffusion-reaction model and cellular automaton. Our results indicate that the benefits of preventing IFN secretion for a virus are strongly determined by spatial struct…
DNA binding of L1 is required for human papillomavirus morphogenesis in vivo.
2002
AbstractThe role of putative DNA-binding domains of human papillomavirus (HPV) capsid proteins for DNA encapsidation in vivo is still unknown. We have now analyzed mutants of the major capsid protein L1 of HPV type 33, which are defective for DNA binding, for their ability to encapsidate DNA using an in vivo packaging approach. Since the DNA-binding domain and the nuclear localization signal (NLS) of L1 overlap, both a carboxy-terminal deletion mutant (L1-1/470) and a substitution mutant (L1-1/477M9) were analyzed. L1-1/477M9 has the classical NLS replaced by a noncanonical NLS taken from the human hnRNP protein A1. The mutant proteins were defective for DNA binding in contrast to wild-type…
The sf32 unique gene of Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV) is a non-essential gene that could be involved in nucleocapsid o…
2013
A recombinant virus lacking the sf32 gene (Sf32null), unique to the Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV), was generated by homologous recombination from a bacmid comprising the complete viral genome (Sfbac). Transcriptional analysis revealed that sf32 is an early gene. Occlusion bodies (OBs) of Sf32null contained 62% more genomic DNA than viruses containing the sf32 gene, Sfbac and Sf32null-repair, although Sf32null DNA was three-fold less infective when injected in vivo. Sf32null OBs were 18% larger in diameter and contained 17% more nucleocapsids within ODVs than those of Sfbac. No significant differences were detected in OB pathogenicity (50% lethal concentration)…
Proteomic Analyses of Human Cytomegalovirus Strain AD169 Derivatives Reveal Highly Conserved Patterns of Viral and Cellular Proteins in Infected Fibr…
2014
Human cytomegalovirus (HCMV) particle morphogenesis in infected cells is an orchestrated process that eventually results in the release of enveloped virions. Proteomic analysis has been employed to reveal the complexity in the protein composition of these extracellular particles. Only limited information is however available regarding the proteome of infected cells preceding the release of HCMV virions. We used quantitative mass spectrometry to address the pattern of viral and cellular proteins in cells, infected with derivatives of the AD169 laboratory strain. Our analyses revealed a remarkable conservation in the patterns of viral and of abundant cellular proteins in cells, infected for 2…
Analysis of the infectious entry pathway of human papillomavirus type 33 pseudovirions.
2002
AbstractHuman papillomavirus type 33 (HPV-33) pseudovirus infection is a slow process dependent on the initial interaction with cell-surface heparan sulfate (T. Giroglou, L. Florin, F. Schafer, R. E. Streeck, and M. Sapp, 2001a, J. Virol. 75, 1565–1570). We have now further dissected the initial steps of pseudovirus uptake using removal of cell-surface proteoglycans and selective inhibition of entry pathways. Treatment of cells with heparinase I, but not with phosphoinositol-specific phospholipase C (PIPLC), prevented binding of papillomavirus-like particles and infection with HPV-33 pseudovirions, indicating that GPI-linked proteoglycans (glypicans) are not required for productive infectio…
Infrared based saliva screening test for COVID‐19
2021
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in an unprecedented need for diagnostic testing that is critical in controlling the spread of COVID-19. We propose a portable infrared spectrometer with purpose-built transflection accessory for rapid point-of-care detection of COVID-19 markers in saliva. Initially, purified virion particles were characterized with Raman spectroscopy, synchrotron infrared (IR) and AFM-IR. A data set comprising 171 transflection infrared spectra from 29 subjects testing positive for SARS-CoV-2 by RT-qPCR and 28 testing negative, was modeled using Monte Carlo Double Cross Validation with 50 randomized test and model sets. The testing se…