Table 1. Summary of genetic differences among three clinical genotypes (CG) and four bovine-biased genotypes (BBG) of EHEC O157 identified using optical mapping technology.
| Total number of genetic rearrangementsc | |||||||
| Strain | SBI Genotypea | Genome size (bp)b | BamHI fragments (No.) | Insertions | Deletions | RFLP | Others |
| E2325 | CG-1 (AY2) | 5,407,641 | 478 | 2 | 6 | 24 | 1 Inv, 3 Sub |
| E5252 | CG-3 (WY12) | 5,376,952 | 488 | 0 | 7 | 7 | 1 Sub |
| E3046 | CG-3 (WY12) | 5,486,716 | 540 | 1 | 0 | 16 | 1 Inv, 1 Sub |
| E5880 | BBG-5 (SY2c) | 5,426,915 | 532 | 2 | 7 | 12 | 2 Inv, 5 Sub |
| E3855 | BBG-5 (SY2c) | 5,390,209 | 500 | 5 | 10 | 16 | 3 Sub |
| E2309 | BBG-6 (ASY12c) | 5,504,252 | 518 | 3 | 6 | 11 | 1 Inv, 1 Tnv, 3 Sub |
| E6996 | BBG-6 (ASY12c) | 5,583,835 | 551 | 4 | 5 | 18 | 4 Sub |
Modified SBI genotype for each isolate is indicated in parenthesis. This shows the concatenation of presence of specific bacteriophage at argW, sbcB, wrbA or yehV locations designated by uppercase first letter of each insertion site (A, S, W or Y,) followed by the presence of stx1, stx2a or stx2c denoted by 1,2 or 2c.
Genome sizes predicted on the basis of optical maps of each strain.
Number of genetic rearrangements in comparison with strain Sakai (CG-3). Insertions = presence of additional restriction fragments; deletions = loss of RE fragments; RFLPs (restriction fragment length polymorphisms) = altered sizes and/or numbers of RE fragments; inversions (Inv) = RE fragments in reversed order; substitutions (Sub) = altered RE fragments; transversion (Tnv) = RE fragments in reversed order and in a different location.