The genetic element pSSVx of the extremely thermophilic crenarchaeon Sulfolobus is a hybrid between a plasmid and a virus

Abstract
A new Sulfolobus islandicus strain, REY15/4, harboured both a novel fusellovirus, SSV2, and a small plasmid, pSSVx. The plasmid spread in S. solfataricus P1 together with the virus after infection wi...