The Osmotic Stress Response Partitions into Distinct Classes of Cellular Function
| Cluster | pvalue | GenProt designation | Description | Observed (F∩C) | Expected (F∩C) |
| 0 | 7.06E-05 | 5.5 | Adaptation to stress | 12 | 4.9 |
| 0 | 5.38E-04 | 5.5.1 | Osmotic pressure | 10 | 4.2 |
| 1 | 8.99E-05 | 1.7.34 | Peptidoglycan (murein) turnover, recycling | 3 | 0.1 |
| 1 | 1.93E-04 | 6 | Cell structure | 6 | 1.5 |
| 2 | 4.32E-03 | 1.6 | Macromolecules (cellular constituent) biosynthesis | 6 | 2.0 |
| 2 | 5.03E-03 | 1.1.1 | Carbon compounds | 11 | 5.3 |
| 2 | 9.11E-03 | 6.4 | Flagellum | 4 | 1.1 |
| 2 | 9.11E-03 | 1.6.12 | Flagella | 4 | 1.1 |
| 2 | 9.11E-03 | 5.3 | Motility (incl. chemotaxis, energytaxis, aerotaxis, redoxtaxis) | 4 | 1.1 |
| 2 | 9.23E-03 | 1.1 | Carbon utilization | 12 | 6.5 |
| 3 | 9.29E-04 | 1.7.1 | Unassigned reversible reactions | 3 | 0.3 |
| 4 | 8.13E-06 | 1.5 | Building block biosynthesis | 13 | 4.2 |
| 4 | 4.41E-04 | 1.5.1 | Amino acids | 9 | 2.9 |
| 5 | 7.06E-04 | 4.S | Substrate | 11 | 4.4 |
| 5 | 8.77E-04 | 4 | Transport | 12 | 5.2 |
| 5 | 2.31E-03 | 4.4.A.6 | The PTS Mannose-Fructose-Sorbose (Man) family | 3 | 0.4 |
| 5 | 6.45E-03 | 1.1 | Carbon utilization | 9 | 4.0 |
| 5 | 6.70E-03 | 1.1.1 | Carbon compounds | 8 | 3.3 |
| 5 | 7.34E-03 | 4.4 | Group translocators | 4 | 1.0 |
| 5 | 7.34E-03 | 4.4.A | Phosphotransferase systems (PEP-dependent PTS) | 4 | 1.0 |
[i] The six clusters were screened using a hypergeometric test measuring statistical enrichment for functional categories from the GenProtEC Escherichia coli database. Observed (F∩C) denotes the number of genes in the specified functional category that are found in the cluster. Expected (F∩C) denotes the number of genes expected by chance to lie within the cluster. P values below 0.01 were deemed significant using Bonferroni correction for multiple hypothesis testing phosphoenolpyruvate (PEP).