Draft Genome Sequence of Pandoravirus japonicus Isolated from the Sabaishi River, Niigata, Japan

Abstract

“Pandoraviridae” is a proposed family of the phylum Nucleocytoviricota. Its features include an amphora-shaped capsid and the largest genome among all viruses. We report the isolation and genome sequencing of a new member of this family, named Pandoravirus japonicus, the third strain discovered in Japan.

Kinetic Analysis of Acanthamoeba castellanii Infected with Giant Viruses Quantitatively Revealed Process of Morphological and Behavioral Changes in Host Cells

“…Mimivirus shirakomae of the Mimiviridae family, kyotovirus of the Marseilleviridae family, medusavirus, and Pandoravirus japonicus of the Pandoraviridae family were isolated in our laboratory from water samples collected in Japan from the Tatakai River in Kyoto (kyotovirus), the Shirakoma Ponds in Nagano ( M. shirakomae ), Japanese hot springs (medusavirus), and the Sabaishi River in Niigata ( P. japonicus ). Isolation of the viruses was performed by screening A. castellanii cells showing CPE in 96-well plates ( 8 , 10 , 18 , 19 ). Each virus propagated using A. castellanii cells in one or several 75-cm 2 flasks was stored in phosphate-buffered saline at 4°C as previously described ( 8 , 10 , 18 , 19 ).…”

“…Isolation of the viruses was performed by screening A. castellanii cells showing CPE in 96-well plates ( 8 , 10 , 18 , 19 ). Each virus propagated using A. castellanii cells in one or several 75-cm 2 flasks was stored in phosphate-buffered saline at 4°C as previously described ( 8 , 10 , 18 , 19 ). The MOI of each virus was calculated as previously described ( 10 ).…”

“…In this study, we updated PKA3 for a more accurate analysis of the cell morphology in high-magnification images and some additional parameters. The new algorithm was used to analyze A. castellanii infected with four types of giant viruses, kyotovirus of the Marseilleviridae family ( 10 ), Mimivirus shirakomae of the Mimiviridae family ( 18 ), medusavirus ( 8 ), and Pandoravirus japonicus of the Pandoraviridae family ( 19 ) isolated in Japan. Infection with these viruses is known to cause cell rounding in A. castellanii .…”

Analysis of Morphological Changes in the Nucleus and Vacuoles of Acanthamoeba castellanii following Giant Virus Infection

“…Figure 3 shows the PKA3 algorithm analysis of A. castellanii infected with four viruses of phylum Nucleocytoviricota , including medusavirus, kyotovirus of the family Marseilleviridae ( 22 ), Mimivirus shirakomae of the family Mimiviridae ( 23 ), and Pandoravirus japonicus of the proposed family Pandoraviridae ( 24 ). Figure 3B shows the rate of A. castellanii cells with the nuclei detected in approximately 60 to 80% of uninfected cells but with a smaller rate of infected cells ( Fig.…”