Figure 3-4: Dot-plot matrix for phage lambda and the eleven lambda-like prophage elements Sp3 to Sp15 from the E. coli strain O157:H7 Sakai. Phage lambda is given as the conventional vegetative map (starting with the cos-site and the packaging genes) while the Sakai prophages start with attL and the integrase gene. Prophages Sp3, 5, 8, 11, 12, 14 and 15 share thus DNA sequence identity with the structural gene cluster of lambda. Prophages Sp3, 4, 8, 9, 10, 14, and 15 share DNA sequence identity with the structural gene cluster of lambda. Sp6 is thus clearly distinct from lambda at the DNA level while it shares long regions of DNA identity with other Sakai prophages. Remarkable is the high degree of DNA sequence identity between the different Sakai prophages since it should lead to frequent genome rearrangements due to homologous recombination between the prophage elements. (for better image quality, click here for tif image, which may be quite large; may also require screen refreshing plus special software to view; or view larger tif in separate window)

Figure 3-1( left,  right ), Figure 3-2, Figure 3-3, Figure 3-4

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