<i>Marseilleviridae</i> Lineage B Diversity and Bunch Formation Inhibited by Galactose

Abstract

Marseilleviridae is a family of large double-stranded DNA viruses that is currently divided into five subgroups, lineages A-E. Hokutovirus and kashiwazakivirus, both of which belong to lineage B, have been reported to induce host acanthamoeba cells to form aggregations called "bunches". This putatively results in increased opportunities to infect acanthamoeba cells, in contrast to lineage A, which has been reported to not form "bunches". In the present study, we isolated 14 virus strains of the family Marseilleviridae from several Japanese water samples, 11 of which were identified as lineage B viruses. All 11 lineage B strains caused infected amoeba cells to form bunches. We then investigated the involvement of monosaccharides in bunch formation by amoeba cells infected with hokutovirus. Galactose inhibited bunch formation, thereby allowing amoeba cells to delay the process, whereas mannose and glucose did not. A kinetic image analysis of hokutovirus-infected amoeba cells confirmed the inhibition of bunch formation by galactose. The number of hokutovirus-infected amoeba cells increased more rapidly than that of tokyovirus-infected cells, which belongs to lineage A. This result suggests that bunch formation by infected amoeba cells is advantageous for lineage B viruses.

Amoebae: Hiding in Plain Sight: Unappreciated Hosts for the Very Large Viruses

“…Such behavior has also been linked to relevant changes in the expression of mannose-binding protein genes by tupanvirus (108) (Figure 5c). Interestingly, a similar CPE has also been described for viruses belonging to a marseillevirus lineage (109).…”

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

“…PKA3 can analyze time-lapse phase-contrast microscopic images of nonlabeled living amoebae and provide output in the form of number, movement, and direction of particles that are considered to be amoebae. To date, only images of Acanthamoeba castellanii cells infected with viruses of the Marseilleviridae family have been analyzed using PKA3 ( 16 , 17 ). However, it can also be used to analyze the behavior of A. castellanii cells infected with giant viruses from other families.…”

Marseilleviruses: An Update in 2021

“…The same year, 15 new marseilleviruses were discovered in sewage, swamp, or wastewater from different locations in Algeria ( Supplementary Table 1 ). Finally, 14 novel marseillevirus isolates have been recently reported from five Japanese aquatic sampling locations, as confirmed by molecular phylogenetic analyses of the major capsid protein (MCP); 11 strains belonged to lineage B, two to lineage A, and one to another lineage close to tokyovirus ( Aoki et al, 2021 ). Therefore, marseilleviruses, like other giant viruses and amoeba, have been shown to be common in water and soil worldwide.…”

“…Marseilleviruses have a large worldwide distribution (nine countries, five continents), being found in samples such as water, soil, mussels, insects, and humans. Accordingly, new marseillevirus isolates continue to be described worldwide, including possible members from new lineages ( Aoki et al, 2021 ). Their presence in both symptomatic and asymptomatic patients deserves further investigation.…”