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Order Picornavirales
Published in Paul Pumpens, Peter Pushko, Philippe Le Mercier, Virus-Like Particles, 2022
Paul Pumpens, Peter Pushko, Philippe Le Mercier
In parallel, Luque et al. (2012) designed several insertion mutants to validate the VP60 (or VP1 in this paper) pseudoatomic model, placed foreign epitopes at the N- or C-terminal end as well as in an exposed loop on the capsid surface, and expressed the chimeric genes by the baculovirus expression system. A set of T- and B-cell epitopes of various lengths derived from viral and eukaryotic origins was employed. Whereas most insertions were well tolerated, VP1 with a feline calicivirus (FCV) capsid protein-neutralizing epitope at the N terminus assembled into mixtures of T = 3 and larger T = 4 capsids (Luque et al. 2012). Figure 27.4 shows the outfit of this novel class of the RHDV-derived capsids.
Ecology
Published in Paul Pumpens, Single-Stranded RNA Phages, 2020
The efficacy levels of different physical and chemical washing treatments were evaluated for the reduction of viral and bacterial pathogens, including the phage MS2 as a surrogate, from inoculated strawberries (Lukasik et al. 2003). The survival of the phage MS2 on lettuce and cabbage was detected together with that of E. coli and feline calicivirus by different temperatures and sanitizers (Allwood et al. 2004a). A stronger correlation of survival measures was observed between feline calicivirus and MS2 than between E. coli and either of the viral agents at 25°C and 37°C. Furthermore, the phage MS2 was applied as a surrogate for norovirus to study the virus survival when it was spiked into fresh produce items such as iceberg lettuce, baton carrot, cabbage, spring onion, curly leaf parsley, capsicum pepper, tomato, cucumber, raspberries, and strawberries (Dawson et al. 2005). It was concluded that MS2 could be used as an effective surrogate in similar studies, since it survived for prolonged periods, both in buffer and on fresh produce, at temperatures relevant to chilled foods, and it was not removed effectively by chlorine washing.
Human Noroviruses
Published in Dongyou Liu, Handbook of Foodborne Diseases, 2018
G. Sanchez, W. Randazzo, D.H. D'Souza
The capacity of HNoVs to maintain infectivity in the environment has mainly been obtained through culturable surrogates, such as feline calicivirus (FCV), murine norovirus (MNV), and more recently, Tulane virus (TV). Even though these models have largely been used to infer the behavior of HNoV, the appropriateness of such surrogates as models still raises questions and needs to be confirmed.24,25 The environmental persistence of HNoV depends on many physical, chemical, and biological factors such as temperature, ionic strength, chemical constituents, microbial antagonism, the status of the virus (such as virus bound to organic matter or virus aggregation), and the type of virus.26 HNoVs showed different behavior and inactivation rates depending on the genotype. Strong evidence suggests that HNoVs are very stable and maintain their infectivity in the environment and food for up to several months.
Hydrogen peroxide vapour treatment inactivates norovirus but has limited effect on post-treatment viral RNA levels
Published in Infectious Diseases, 2019
Torsten Holmdahl, Inga Odenholt, Kristian Riesbeck, Patrik Medstrand, Anders Widell
Noroviruses are divided into at least five genogroups. Three of them (I, II and IV), infect humans while norovirus genogroup III infects cattle, and genogroup V, (the murine norovirus), infects mice. Human norovirus and murine norovirus are structurally similar and share tissue tropism for enterocytes in the gut of the respective species [11]. Another calicivirus, although not classified as a norovirus, which is often used for research is the feline calicivirus [12], a respiratory virus, which causes significant morbidity in cats [13].
Application of selected biosensor techniques in clinical diagnostics
Published in Expert Review of Molecular Diagnostics, 2021
Beata Olejnik, Agata Kozioł, Ewa Brzozowska, Mirosława Ferens-Sieczkowska
Attempts at the application of SPR-based methods in the diagnosis of viral infections cover recent years, when the global threat of new viral epidemics increased. In 2013, Yu et al. [121] developed a silver nanoisland sensor for the sensitive trapping of adenoviruses. In this experiment, however, the binding was nonspecific so the method was applicable only to the evaluation of virions cultivated in vitro; the lack of specific capture prevented its diagnostic use. This barrier was overcome at about the same time by the team of Yakes et al. [122], who designed a sensor with a typical sandwich system used in ELISA immunoassay techniques. The test was used to detect feline calicivirus, the equivalent of extremely infectious human noroviruses. Intact viral particles isolated from foodstuffs were captured by specific antibodies immobilized on the sensor surface and generated a first SPR signal, further amplified by the attachment of a second (detection) antibody, which in this case did not need to be labeled. Soon there were reports on the development of sensors with hepatitis B antigens, and antibodies that specifically recognize them were imprinted on the gold surface in the form of microarrays, which allowed multiplex detection of several HB antigens and antibodies using a single chip (device) in a 20μL serum sample, with 85% agreement with ELISA data [123]. Ashiba et al. [124] used SPR-assisted fluoroimmunoassay for the sensitive detection of above-mentioned noroviruses causing severe gastroenteritis. Quantum dot fluorescence was used to enhance the sensitivity of detection. The sensor was designed to excite Q-dot fluorescent dyes by an enhanced electric field induced by SPR on Al film. Gold, commonly used as a sensor, is not compatible with the excitation (390 nm) and emission (705 nm) ranges of the Q-dots used, so it was replaced with aluminum. Shi et al. [125] used SPR to distinguish nine respiratory viruses, which cross-reacted in PCR reactions. The viral material was precisely bound to complementary oligonucleotide probes in this study. H5N1 avian influenza virus aptasensors were used by Bai et al. [126]. A commercially available miniature chip from Texas Instruments with a streptavidin-coated gold sensor was functionalized with a biotinylated hemagglutinin-specific aptamer and thus ready to bind viral surface protein. The authors achieved binding of the analyte with a KD constant of 4.65 nM. A pair of specific aptamers was used for H5Nx viruses by Nguyen et al, [127]. Also, last year, the sensitive detection of Dengue virus protein on the graphen-based sensor was reported [9].