The polymycovirus-mediated growth enhancement of the entomopathogenic fungus Beauveria bassiana is dependent on carbon and nitrogen metabolism
File(s)
Published version
Author(s)
Filippou, Charalampos
Diss, Rebecca
Daudu, John
Coutts, Robert
Kotta-Loizou, Ioly
Type
Journal Article
Abstract
Polymycoviridae is a growing family of mycoviruses whose members typically have non-conventional capsids and multi-segmented, double-stranded (ds) RNA genomes. Beauveria bassiana polymycovirus (BbPmV) 1 is known to enhance the growth and virulence of its fungal host, the entomopathogenic ascomycete and popular biological control agent B. bassiana. Here we report the complete sequence of BbPmV-3, which has six genomic dsRNA segments. Phylogenetic analysis of RNA-dependent RNA polymerase (RdRp) protein sequences revealed that BbPmV-3 is closely related to the partially sequenced BbPmV-2 but not BbPmV-1. Nevertheless, both BbPmV-3 and BbPmV-1 have similar effects on their respective host isolates ATHUM 4946 and EABb 92/11-Dm, affecting pigmentation, sporulation, and radial growth. Production of conidia and radial growth are significantly enhanced in virus-infected isolates as compared to virus-free isogenic lines on Czapek-Dox complete and minimal media that contain sucrose and sodium nitrate. However, this polymycovirus-mediated effect on growth is dependent on the carbon and nitrogen sources available to the host fungus. Both BbPmV-3 and BbPmV-1 increase growth of ATHUM 4946 and EABb 92/11-Dm when sucrose is replaced by lactose, trehalose, glucose, or glycerol, while the effect is reversed on maltose and fructose. Similarly, both BbPmV-3 and BbPmV-1 decrease growth of ATHUM 4946 and EABb 92/11-Dm when sodium nitrate is replaced by sodium nitrite, potassium nitrate, or ammonium nitrate. In conclusion, the effects of polymycoviruses on B. bassiana are at least partially mediated via its metabolic pathways.
Date Issued
2021-02-02
Date Acceptance
2021-01-04
Citation
Frontiers in Microbiology, 2021, 12
ISSN
1664-302X
Publisher
Frontiers Media
Journal / Book Title
Frontiers in Microbiology
Volume
12
Copyright Statement
© 2021 Filippou, Diss, Daudu, Coutts and Kotta-Loizou. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
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Subjects
Beauveria bassiana
Polymycoviridae
fungal growth
fungal sporulation
mycovirus
0502 Environmental Science and Management
0503 Soil Sciences
0605 Microbiology
Publication Status
Published
Article Number
ARTN 606366