FIG 1.

Genome maps of phages 21 and 434. Maps of phages 21, λ, and 434 are shown with selected λ genes indicated; homologs in 21 and 434 are marked by the λ gene name. At the bottom, the major transcription units are indicated by horizontal arrows: red, early left and right operons; black, late operons; green, repressor transcript expressed in the lysogen. The universal order of gene functions in the λ-like phages is shown at the bottom. Gray areas between maps indicate regions of homology, with the percent identity values shown.