First isolation of a giant virus in wild Hirudo medecinalis leech. Hirudovirus

We describe the isolation, by coculture on Acanthamoeba sp., of a giant virus from the family of Mimiviridae from a wild specimen of a medical leech Hirudo medicinalis. It was named Hirudovirus. The Hirudovirus genome was sequenced on the 454 Roche sequencer device. A rough analyis of this genome was performed using BLAST p searches against other mimivruses, the NCBI international proteic sequences database, and the recently described Pandoravirus dulcis and Pandoravirus salinus genomes. Transfer RNA were searched for using the ARAGORN software. The sequenced genome assembly resulted in two scaffolds of 1,155,382 and 25,660 bases pairs, with a mean GC content of 28%. A total of 992 ORFs were identified in the draft genome of Hirudovirus. Four tRNA synthetases and 6 transfer RNA were found in the Hirudovirus genome.The rough analysis of the 1.18Mb genome sequence of Hirudovirus showed a gene content closely relative to those of Acanthamoeaba polyphaga mimivirus (APMV) and Acanthamoeba castellani mamavirus. The phylogenetic analysis showed a closely relationship between Hirudovirus and the mimiviruses belonging to the lineage A, APMV and Acanthamoeba castellani mamavirus.