Table 1.
COG codes for general function and pathway/systems
| Code | Genes | Description |
| General function | ||
| 416 | Information storage and processing | |
| J | 242 | Translation, ribosomal structure and biogenesis |
| K | 80 | Transcription |
| L | 94 | DNA replication, recombination and repair |
| 429 | Metabolism | |
| C | 62 | Energy production and conversion |
| G | 71 | Carbohydrate transport and metabolism |
| E | 153 | Amino acid transport and metabolism |
| F | 50 | Nucleotide transport and metabolism |
| H | 54 | Coenzyme metabolism |
| I | 39 | Lipid metabolism |
| 226 | Cellular processes | |
| D | 4 | Cell division and chromosome partitioning |
| O | 98 | Posttranslational modification, protein turnover, chaperones |
| M | 9 | Cell envelope biogenesis, outer membrane |
| N | 6 | Cell motility and secretion |
| P | 71 | Inorganic ion transport and metabolism |
| T | 38 | Signal transduction mechanisms |
| 127 | Poorly characterized | |
| R | 119 | General function prediction only |
| S | 8 | Function unknown |
| Pathway/system | ||
| - | 613 | No pathway/system assigned |
| C1 | 2 | Pyruvate decarboxylation |
| C2 | 18 | TCA cycle |
| C3 | 3 | Glyoxylate bypass |
| E1 | 6 | Arginine biosynthesis |
| E2 | 3 | Phenylalanine/tyrosine biosynthesis |
| E3 | 3 | Tryptophan biosynthesis |
| E4 | 2 | Threonine biosynthesis |
| E5 | 1 | Isoleucine biosynthesis |
| E7 | 19 | Leucine biosynthesis |
| E8 | 7 | Methionine biosynthesis |
| E9 | 4 | Proline biosynthesis |
| E10 | 4 | Histidine biosynthesis |
| F1 | 15 | Purine biosynthesis |
| F2 | 3 | Purine salvage |
| F3 | 12 | Pyrimidine biosynthesis |
| F4 | 2 | Pyrimidine salvage |
| F5 | 7 | Thymidylate biosynthesis |
| G1 | 4 | Glycolysis |
| G2 | 14 | Gluconeogenesis |
| G3 | 6 | Pentose phosphate pathway |
| G4 | 4 | Entner-doudoroff pathway |
| H1 | 8 | Heme biosynthesis |
| H3 | 2 | FAD biosynthesis |
| H4 | 7 | Biotin biosynthesis |
| H5 | 1 | NAD biosynthesis |
| H6 | 7 | Ubiquinone biosynthesis |
| H7 | 3 | Menaquinone biosynthesis |
| H8 | 2 | Thiamine biosynthesis |
| H9 | 1 | Pyridoxal phosphate biosynthesis |
| I1 | 10 | Fatty acid biosynthesis |
| J1 | 26 | Translation factors and enzymes involved in translation |
| J2 | 30 | Aminoacyl-tRNA synthetases, amino acid activation |
| J3 | 47 | Ribosomal proteins - small subunit |
| J4 | 77 | Ribosomal proteins - large subunit |
| K1 | 14 | DNA-dependent RNA polymerase subunits |
| K2 | 7 | Basal transcription factors |
| K3 | 2 | Transcriptional regulators |
| L1 | 20 | Basal replication machinery |
The COG letter-codes for general function and pathway/system categories are given the first column (Code). The Genes column holds the number of genes in the microarray data studied that were found for each functional class. The last column (Description) gives the description for each category.