Jumbo phages use a membrane-bound EPI vesicle and then the phage nucleus to compartmentalize their genomes (Cell Host & Microbe)

Bacteriophages of the Chimalliviridae family are shown to use two successive compartments during infection: a membrane-bound early phage infection (EPI) vesicle that encloses the injected genome and expresses early genes, and the protein-lattice phage nucleus to which the DNA is transferred before genome replication begins. The authors describe the EPI vesicle as a transcriptionally active, membrane-bound organelle formed by a prokaryotic virus.