First evidence of host range expansion in virophages and its potential impact on giant viruses and host cells

Said Mougari; Nisrine Chelkha; Dehia Sahmi-Bounsiar; Fabrizio Di Pinto; Philippe Colson; Jonatas Abrahao; Bernard La Scola

To investigate whether mutant Guarani was able to maintain the deletion mutation during several passages with Tupanvirus, A. castellanii cells at a concentration of 5.10 5 cell/ml in 10 ml PYG medium were inoculated with Tupanvirus Deep Ocean and Guarani wild-type genotype at MOIs of 10. The coculture was incubated at 30°C until complete lysis of amoebas was observed. To perform serial flask passaging, 100 µl of the virus-virophage supernatant collected from this primo coculture was used to infect fresh A. castellanii cells seeded at a 5. To evaluate whether mutant Guarani was able to inhibit the production of Tupanvirus infectious particles during a passage experiment, A. castellanii cells at a 5. 10 5 cells/ml density in 10 ml PYG medium were simultaneously coinfected with Tupanvirus Deep Ocean at an MOI of 10 and 100 µl of Guarani mixture containing both wild-type and mutant author/funder. All rights reserved. No reuse allowed without permission.