Medusavirus

Medusavirus is a nucleocytoplasmic large DNA virus first isolated from a Japanese hot spring. It notably encodes all five types of histones — H1, H2A, H2B, H3, and H4 — which are involved in DNA packaging in eukaryotes. The virus can harden amoebas of the species "Acanthamoeba castellanii" into stone-like cysts, but infection usually causes infected amoebas to burst open. The virus was named after Medusa, the monster in Greek mythology whose gaze turned people to stone.