Figure 5. Comparison of the Sp5 late region with three well-characterized Podoviridae family phages.

The genes (or ORFs) of each phage are numbered according to Asadulghani et al.³² for Sp5, Pedulla et al.⁴ for P22, Dunn & Studier⁶⁸ for T7, and accession number NC_008720 for phi29. Essential genes are colored, and open arrows indicate non-essential genes. Genes with the same or similar functions are depicted in the same color, as indicated in the inset. Head completion/neck proteins are included in the “tail formation” category. Note that the ORF64 and ORF76 mutants (marked by asterisks) showed markedly reduced infectivity but were still infectious (see Fig. 1 and the main text). In T7, gp10B (light green in the figure) encodes a minor capsid protein.