China
Africa
Explore chapters and articles related to this topic
Order Tymovirales
Published in Paul Pumpens, Peter Pushko, Philippe Le Mercier, Virus-Like Particles, 2022
Paul Pumpens, Peter Pushko, Philippe Le Mercier
Figure 21.1 demonstrates portraits and schematic cartoons of the typical representatives of the two most interesting families. The Alphaflexiviridae members are looking like flexuous filaments, usually 12–13 nm (in a range 10–15 nm) in diameter and from 470–800 nm in length, depending on the genus. The viral capsid is composed of a single polypeptide ranging in size from 18–43 kDa except for members of the genus Lolavirus, which have two C-coterminal capsid protein variants, and members of the genus Sclerodarnavirus, in which no capsid protein has been identified (Kunze et al. 2020). The Tymoviridae is the only family within the order Tymovirales that has viruses with isometric particles. The virions are nonenveloped, about 30 nm in diameter, and made up of 20 hexameric and 12 pentameric subunits arranged in a T = 3 icosahedron. The RNA appears to be at least partially ordered in an icosahedral arrangement in the center of the protein shell (Dreher et al. 2012).
Metagenomic analysis of intestinal mucosa revealed a specific eukaryotic gut virome signature in early-diagnosed inflammatory bowel disease
Published in Gut Microbes, 2019
Federica Ungaro, Luca Massimino, Federica Furfaro, Valeria Rimoldi, Laurent Peyrin-Biroulet, Silvia D’Alessio, Silvio Danese
Conversely, other viral families, such as Polydnaviridae and Tymoviridae in UC, and Virgaviridae in CD, that we observed to be less enriched in IBD patients and to negatively correlate with the presence of other viruses, might be somehow considered protective in the human host.15 This is interesting, because Polydnaviridae, Tymoviridae, and Virgaviridae are viruses that typically infects plants and insects and may have reached the gut through the diet.3 The trans-kingdom interaction15 between viruses and hosts, such as plant and insect viruses that colonize human tissues, has already been reported in the past for Tobacco Mosaic Virus (TMV), against which antibodies were found in human sera.42 Unlike animal viruses, plant viruses cannot replicate in humans or other animals because of the lack of specific receptors. Nevertheless, they still can induce the host immune response, as shown for the cowpea mosaic virus in mice.43,44