Kaumoebavirus, a New Virus That Clusters with Faustoviruses and Asfarviridae

Abstract

In this study, we report the isolation of a new giant virus found in sewage water from the southern area of Jeddah (Saudi Arabia), with morphological and genomic resemblance to Faustoviruses. This new giant virus, named Kaumoebavirus, was obtained from co-culture with Vermamoeba vermiformis, an amoeboid protozoa considered to be of special interest to human health and the environment. This new virus has ~250 nm icosahedral capsids and a 350,731 bp DNA genome length. The genome of Kaumoebavirus has a coding density of 86%, corresponding to 465 genes. Most of these genes (59%) are closely related to genes from members of the proposed order Megavirales, and the best matches to its proteins with other members of the Megavirales are Faustoviruses (43%) and Asfarviruses (23%). Unsurprisingly, phylogenetic reconstruction places Kaumoebavirus as a distant relative of Faustoviruses and Asfarviruses.

Pacmanvirus, a New Giant Icosahedral Virus at the Crossroads between Asfarviridae and Faustoviruses

“…Indeed, with faustovirus and kaumoebavirus analyses (15,16), we observed that small coding sequences were conserved and may encode elements constituting the viral capsid. Finally, in the absence of transcriptomic and proteomic analyses, we decided to keep 465 genes in the pacmanvirus gene repertoire, which represents a coding density of about 89.3% along the 353,121 bp (mean GC% of the coding sequences Ϸ 34.7%).…”

“…The major capsid protein is encoded in a single ORF in pacmanvirus and ASFV, while it is located in different loci in the case of kaumoebavirus and faustoviruses. We do not know if this process is related to host range as for the double protein capsid studied for faustovirus (15,17,19) and the predicted capsid protein of kaumoebavirus (16). Despite all this, the ASFV virion structure includes an outer lipid membrane, an icosahedral protein capsid, and an inner lipid membrane (29) that is strongly involved in cell infection.…”

“…A total information set of 8.3 Gb was obtained, with a 910,000/mm 2 cluster density and with a cluster-passing quality control filter of 92.8% (16,316,457 passed filter clusters). Within this run, the index representation for pacmanvirus A23 was determined to be 3.44%.…”

“…In 2015, we reported the isolation of a new virus, faustovirus (15), using the protist Vermamoeba vermiformis as a cell support in our coculture process. Another virus, kaumoebavirus, was isolated using the same strategy (16). These two viruses represent a new group which is most closely related to asfarviruses, raising the question of whether they are distant relatives of asfarviruses or comprise putative new families.…”

Genome Sequences of New Faustovirus Strains ST1 and LC9, Isolated from the South of France

“…Analyses of their genomes have revealed homology with Asfarviridae and kaumoebavirus, suggesting a shared origin (2, 3). Here, we report the complete genome sequence of faustovirus strain ST1 and the draft genome annotation of faustovirus strain LC9.…”