The complete genome sequences of a negative single-stranded RNA virus and a double-stranded RNA virus coinfecting the entomopathogenic fungus Beauveria bassiana Vuillemin

AbstractBeauveria bassiana Vuillemin is an entomopathogenic fungus that has been developed as a biological insecticide.B. bassiana can be infected by single or multiple mycoviruses, most of which are double-stranded RNA (dsRNA) viruses, while infections with single-stranded RNA (ssRNA) viruses, especially negative single-stranded RNA (-ssRNA) viruses, have been observed less frequently. In the present study, we sequenced and analyzed the complete genomes of two new different mycoviruses coinfecting a singleB. bassiana strain: a -ssRNA virus which we have named"Beauveria bassiana negative-strand RNA virus 1" (BbNSRV1), and a dsRNA virus, which we have named"Beauveria bassiana orthocurvulavirus 1" (BbOCuV1). The genome of BbNSRV1 consists of a single segment of negative-sense, single-stranded RNA with a length of 6169 nt, containing a single open reading frame (ORF) encoding a putative RNA-dependent RNA polymerase (RdRp) with 1949 aa (220.1 kDa). BLASTx analysis showed that the RdRp had the highest sequence similarity (59.79%) to that of Plasmopara viticola lesion associated mononegaambi virus 2, a member of the familyMymonaviridae. This is the first report of a -ssRNA mycovirus infectingB. bassiana. The genome of BbOCuV1 consists of two dsRNA segments, 2164 bp and 1765 bp in length, respectively, with dsRNA1 encoding a protein with conserved RdRp motifs and 70.75% sequence identity to the putative RdRp of the taxonomically unassigned mycovirus Fusarium gram...

Source: Archives of Virology - February 8, 2024 Category: Virology Source Type: research