PhageD long terminal repeats share structural similarity
but few gene sequences with bacteriophage SPO1.
The accompanying slides show a 6942 bp terminal direct repeat
for phageD with 21 small ORFs driven by 15 near perfect B. subtilis
sigma A (vegetative) promoters.
This arrangement is highly reminiscent to the organization
of the long terminal repeats in bacteriophage SPO1 (Stewart
et al., 1998).
The SPO1 terminal repeat is termed the "host takeover" module,
because it contains early genes that co-opt the host metabolism.
However, only 2 of the genes are homologous to SPO1 genes.
One ORF has small homologues in a few other phages, and is
also homologous to a domain in Bxz1 tape measure.