Summary of Results for 42 Organisms
| Species | No. of predicted operons | Genome size (Mb) | No. of enzymes in operons/No. of total enzymes[i] | Ratio of enzymes of operons | Average length of operons | Number of operons in a shuffled genome | P-value |
| E. coli | 124 | 4.7 | 374/562 | 0.66 | 3.0 | 22 | 0.001 |
| H. influenzae | 52 | 1.8 | 160/293 | 0.54 | 3.1 | 11 | 0.006 |
| X. fastidiosa | 42 | 2.7 | 148/365 | 0.39 | 3.5 | 5 | 0.005 |
| V. cholerae | 80 | 4.0 | 237/562 | 0.42 | 3.0 | 11 | 0.001 |
| P. aeruginosa | 101 | 6.4 | 290/715 | 0.41 | 2.9 | 14 | 0.002 |
| Buchnera sp APS | 30 | 0.7 | 122/224 | 0.54 | 4.1 | 8 | 0.02 |
| P. multocida | 57 | 2.3 | 169/418 | 0.40 | 3.0 | 12 | 0.004 |
| N. meningitidis B | 38 | 2.3 | 134/404 | 0.33 | 3.5 | 8 | 0.007 |
| H. pylori | 25 | 1.7 | 81/280 | 0.29 | 3.2 | 6 | 0.02 |
| C. jejuni | 33 | 1.7 | 112/335 | 0.33 | 3.4 | 8 | 0.009 |
| R. prowazekii | 25 | 1.1 | 71/182 | 0.39 | 2.8 | 6 | 0.007 |
| M. lot̂i | 88 | 7.1 | 260/729 | 0.36 | 3.0 | 8 | 0.003 |
| C. crescentus | 48 | 4.1 | 135/372 | 0.36 | 2.8 | 5 | 0.004 |
| B. subtilis | 105 | 4.3 | 323/510 | 0.63 | 3.1 | 13 | 0.001 |
| B. halodurans | 98 | 4.3 | 308/563 | 0.55 | 3.1 | 13 | 0.001 |
| M. genitalium | 13 | 0.6 | 40/86 | 0.47 | 3.1 | 5 | 0.10 |
| M. pneumoniae | 17 | 0.8 | 50/117 | 0.43 | 2.9 | 6 | 0.03 |
| M. pulmonis | 19 | 1.0 | 60/116 | 0.52 | 3.2 | 4 | 0.01 |
| U. urealyticum | 11 | 0.8 | 33/101 | 0.33 | 3.0 | 3 | 0.04 |
| L. lactis | 62 | 2.4 | 203/367 | 0.55 | 3.3 | 9 | 0.002 |
| S. pyogenes | 46 | 1.9 | 152/283 | 0.54 | 3.3 | 10 | 0.001 |
| S. aureus Mu50 | 6 | 2.9 | 21/43 | 0.49 | 3.5 | 0 | 0.005 |
| M. tuberculosis | 89 | 4.5 | 266/591 | 0.45 | 3.0 | 16 | 0.003 |
| M. leprae | 47 | 3.3 | 134/326 | 0.41 | 2.9 | 4 | 0.002 |
| C. trachomatis | 27 | 1.0 | 81/187 | 0.43 | 3.0 | 5 | 0.007 |
| C. pneumoniae | 24 | 1.2 | 75/190 | 0.39 | 3.1 | 4 | 0.007 |
| B. burgdorferi | 20 | 1.5 | 50/138 | 0.36 | 2.5 | 2 | 0.001 |
| T. pallidum | 15 | 1.2 | 44/152 | 0.29 | 2.9 | 5 | 0.03 |
| Synechocystis | 24 | 3.6 | 59/453 | 0.13 | 2.5 | 8 | 0.02 |
| D. radiodurans | 46 | 2.7 | 136/434 | 0.31 | 3.0 | 7 | 0.002 |
| A. aeolicus | 31 | 1.6 | 90/387 | 0.23 | 2.9 | 10 | 0.01 |
| T. maritima | 42 | 1.9 | 172/368 | 0.47 | 4.1 | 7 | 0.005 |
| M. jannaschii | 28 | 1.7 | 96/274 | 0.35 | 3.4 | 9 | 0.01 |
| M. thermoautotrophicum | 46 | 1.8 | 164/349 | 0.47 | 3.6 | 10 | 0.006 |
| A. fulgidus | 59 | 2.2 | 178/406 | 0.44 | 3.0 | 13 | 0.003 |
| T. acidophilum | 34 | 1.6 | 107/271 | 0.39 | 3.2 | 8 | 0.03 |
| T. volcanium | 35 | 1.6 | 116/277 | 0.42 | 3.3 | 7 | 0.006 |
| P. horikoshii | 23 | 1.8 | 80/231 | 0.35 | 3.5 | 4 | 0.01 |
| P. abyssi | 30 | 1.8 | 125/280 | 0.45 | 4.2 | 6 | 0.009 |
| A. pernix | 33 | 1.7 | 95/274 | 0.37 | 2.9 | 4 | 0.004 |
| S. solfataricus | 59 | 3.0 | 190/458 | 0.41 | 3.2 | 11 | 0.007 |
| S. cerevisiae | 33 | 13 | 74/692 | 0.11 | 2.2 | 16 | 0.047 |
[i] The total number of enzymes that are involved in the metabolic pathways.