FIG 4.

Representation of the 6 “superviral hallmark genes” in virus genomes of the seven Baltimore classes. The “superviral hallmark proteins” are shown by ribbon diagrams of the representative protein structures. The lines connect the proteins with the viruses of BCs in which they are present. The thickness of each connecting line roughly reflects the abundance of a given “superhallmark” gene in a given BC. DJR-CP, double-jelly-roll capsid protein; RCRE, rolling-circle replication (initiation) endonuclease; RdRp, RNA-directed RNA polymerase; RT, reverse transcriptase; S3H, superfamily 3 helicase; SJR-CP, single-jelly-roll capsid protein.