Mycovirus

As Mykoviren ( ancient Greek μύκης mykes: Mushroom ) refers to those viruses which have various fungi and yeasts to the host. In the non- taxonomic group Mykoviren to virus species are so far from nine very different virus families ( Barnaviridae, Chrysoviridae, Hypoviridae, Metaviridae, Narnaviridae, Partitiviridae, Pseudoviridae, Reoviridae and Totiviridae ) and the unclassified genus Rhizidiovirus.

The detectable in spores and hyphae Mykoviren mainly cause no disease in fungi ( hypovirulence ) and spread almost exclusively by cell division of the host cell ( vertical transmission ) or cell fusion. A outside the cell taking place infection cycle is absent in most Mykoviren, also exist partly no extracellular virions. It is found in the cytoplasm of the fungal cell only virus-like particles ( virus - like particles, VLPs ) as a sign of infection. Because of these properties of hypovirulence and the absence of virus particles outside the cell, the Mykoviren are also called crypto viruses ( gr κρύπτος: hidden) called.

Discovery

The first indication of viruses in fungi found in 1968 in studies on cultured cultivated mushrooms (Agaricus bisporus ) that were affected by a severe growth failure. In the hyphae of mushrooms VLPs could be identified. 1970 were found in hyphae of Aspergillus foetidus also VLPs and viral double-stranded RNA. Since these initial discoveries were based on viral infections in fungi on studies in diseases of fungi, the vast majority of non-pathogenic Mykoviren was discovered and characterized until the 1980s and 90s by nucleic acid hybridization and PCR studies.

Occurrence

Mykoviren are present in fungal species different taxonomic groups worldwide, including the Ascomycota ( ascomycetes ), Stand mushrooms ( Basidiomycetes ) and not to the mushrooms scoring Eipilze ( Peronosporomycetes ). In various types of yeast, which also have economic importance as the brewer's yeast, Mykoviren are responsible for the synthesis of so-called "killer toxins ". These are produced by the virus-infected yeast glycoproteins to uninfected yeast strains other (but the same species) have a toxic effect by damaging the cell membrane or the DNA synthesis apparatus (killer yeasts).

Swell

• M. Hollings: Mycoviruses: viruses did infect fungi. Adv Virus Res (1978 ) 22: pp. 1-53 (Review) PMID 345 774
• S. Tavantzis: Partitiviruses of Fungi. In: Brian WJ Mahy and Marc H. van Regenmortel (eds. ): Encyclopedia of Virology, 3rd Edition, San Diego 2008, Volume 4, pp. 63ff, ISBN 978-0-12-373935-3