Genomic characterization of a novel bunyavirus FsBV1 from Fusarium solani.

A novel bunyavirus, tentatively named Fusarium solani bunyavirus 1 (FsBV1), was identified in the phytopathogenic fungus Fusarium solani. The complete sequence of the L segment of FsBV1 is 7,186 nucleotides (nt) in length and contains a single open reading frame (ORF) encoding an RNA-dependent RNA polymerase (RdRp) of 316 amino acids (aa). The RdRp contains six conserved bunyaviral motifs, including the SDD tripeptide. The M segment is 1,422 nt long and contains a single ORF encoding a YwqJ-like deaminase of 81 aa. The S segment is 1,301 nt long and contains a single ORF encoding a protein containing putative multifunctional flavoprotein (SiRFP) domain. BLASTp analysis showed that the RdRp of FsBV1 shared the highest amino acid sequence identity (48.73%) with that of Cheeloo tick associated virus 2. Phylogenetic analysis revealed that FsBV1 clusters with unclassified bunyaviruses. Based on its genome organization, protein sequences, and phylogenetic position, FsBV1 is proposed as a novel virus within the class Bunyaviricetes.