A penta-segmented chrysovirus from Penicillium rubens expands the genomic diversity of alphachrysoviruses.

In the present study, a Pakistani isolate of a known chrysovirus was identified in Penicillium rubens strain S25 tentatively named as Penicillium rubens chrysovirus 1 (PrCV1). PrCV1 has five genomic segments, ranging from 0.5 to 3.7 kbp in length. Analysis of the RNA-dependent RNA polymerase (RdRP) amino acid sequence revealed a 99.28% identity with the genome of Penicillium chrysogenum chrysovirus, suggesting a close evolutionary relationship. Notably, a fifth segment, absent in P. chrysogenum, was identified and is described here for the first time in P. rubens. Sequence analysis showed that this fifth segment is 514 bp in length and has a 5'-terminus identical to the other four segments but it differs in the Box-1 region and lacks the characteristic CAA repeats.