Genome comparison between Escherichia coli phage Mu and PaMx73. The genome maps of phage Mu, modified from , and PaMx73 are drawn to scale. The ORFs in both maps are represented by color coded arrows, as in Figure 4, adding the yellow arrows that represent accessory ORFs. Putative promoters identified in PaMx73 and those reported for Mu  are marked with angled black arrows. Some genes above phage Mu map are labeled with the functions that they encode . Core ORFs in PaMx73 genome are numbered and the position of the regions of genome plasticity, RGPs A to I is indicated. The ORFs of Mu and PaMx73 were compared using BLASTp and the ORFs showing sequence similarity are connected by cyan lines between the two maps. The percentages of sequence similarity between the connected genes are indicated. Black lines connect ORFs encoding the same function, but showed no sequence homology.