| COG0003 | Oxyanion-translocating ATPase |
| COG0004 | Ammonia permease |
| COG0025 | NhaP-type Na+/H+ and K+/H+ antiporters |
| COG0038 | Chloride channel protein EriC |
| COG0053 | Predicted Co/Zn/Cd cation transporters |
| COG0155 | Sulfite reductase, beta subunit (hemoprotein) |
| COG0168 | Trk-type K+ transport systems, membrane components |
| COG0226 | ABC-type phosphate transport system, periplasmic component |
| COG0248 | Exopolyphosphatase |
| COG0288 | Carbonic anhydrase |
| COG0306 | Phosphate/sulphate permeases |
| COG0310 | ABC-type Co2+ transport system, permease component |
| COG0369 | Sulfite reductase, alpha subunit (flavoprotein) |
| COG0370 | Fe2+ transport system protein B |
| COG0376 | Catalase (peroxidase I) |
| COG0387 | Ca2+/H+ antiporter |
| COG0428 | Predicted divalent heavy-metal cations transporter |
| COG0444 | ABC-type dipeptide/oligopeptide/nickel transport system, ATPase component |
| COG0471 | Di- and tricarboxylate transporters |
| COG0474 | Cation transport ATPase |
| COG0475 | Kef-type K+ transport systems, membrane components |
| COG0477 | Permeases of the major facilitator superfamily |
| COG0490 | Putative regulatory, ligand-binding protein related to C-terminal domains of K+ channels |
| COG0529 | Adenylylsulfate kinase and related kinases |
| COG0530 | Ca2+/Na+ antiporter |
| COG0569 | K+ transport systems, NAD-binding component |
| COG0573 | ABC-type phosphate transport system, permease component |
| COG0581 | ABC-type phosphate transport system, permease component |
| COG0598 | Mg2+ and Co2+ transporters |
| COG0600 | ABC-type nitrate/sulfonate/bicarbonate transport system, permease component |
| COG0601 | ABC-type dipeptide/oligopeptide/nickel transport systems, permease components |
| COG0605 | Superoxide dismutase |
| COG0607 | Rhodanese-related sulfurtransferase |
| COG0609 | ABC-type Fe3+-siderophore transport system, permease component |
| COG0614 | ABC-type Fe3+-hydroxamate transport system, periplasmic component |
| COG0619 | ABC-type cobalt transport system, permease component CbiQ and related transporters |
| COG0651 | Formate hydrogenlyase subunit 3/Multisubunit Na+/H+ antiporter, MnhD subunit |
| COG0659 | Sulfate permease and related transporters (MFS superfamily) |
| COG0672 | High-affinity Fe2+/Pb2+ permease |
| COG0704 | Phosphate uptake regulator |
| COG0715 | ABC-type nitrate/sulfonate/bicarbonate transport systems, periplasmic components |
| COG0725 | ABC-type molybdate transport system, periplasmic component |
| COG0735 | Fe2+/Zn2+ uptake regulation proteins |
| COG0748 | Putative heme iron utilization protein |
| COG0753 | Catalase |
| COG0783 | DNA-binding ferritin-like protein (oxidative damage protectant) |
| COG0798 | Arsenite efflux pump ACR3 and related permeases |
| COG0803 | ABC-type metal ion transport system, periplasmic component/surface adhesin |
| COG0855 | Polyphosphate kinase |
| COG0861 | Membrane protein TerC, possibly involved in tellurium resistance |
| COG1006 | Multisubunit Na+/H+ antiporter, MnhC subunit |
| COG1009 | NADH:ubiquinone oxidoreductase subunit 5 (chain L)/Multisubunit Na+/H+ antiporter, MnhA subunit |
| COG1055 | Na+/H+ antiporter NhaD and related arsenite permeases |
| COG1108 | ABC-type Mn2+/Zn2+ transport systems, permease components |
| COG1116 | ABC-type nitrate/sulfonate/bicarbonate transport system, ATPase component |
| COG1117 | ABC-type phosphate transport system, ATPase component |
| COG1118 | ABC-type sulfate/molybdate transport systems, ATPase component |
| COG1119 | ABC-type molybdenum transport system, ATPase component/photorepair protein PhrA |
| COG1120 | ABC-type cobalamin/Fe3+-siderophores transport systems, ATPase components |
| COG1121 | ABC-type Mn/Zn transport systems, ATPase component |
| COG1122 | ABC-type cobalt transport system, ATPase component |
| COG1124 | ABC-type dipeptide/oligopeptide/nickel transport system, ATPase component |
| COG1135 | ABC-type metal ion transport system, ATPase component |
| COG1173 | ABC-type dipeptide/oligopeptide/nickel transport systems, permease components |
| COG1178 | ABC-type Fe3+ transport system, permease component |
| COG1218 | 3'-Phosphoadenosine 5'-phosphosulfate (PAPS) 3'-phosphatase |
| COG1226 | Kef-type K+ transport systems, predicted NAD-binding component |
| COG1230 | Co/Zn/Cd efflux system component |
| COG1275 | Tellurite resistance protein and related permeases |
| COG1276 | Putative copper export protein |
| COG1283 | Na+/phosphate symporter |
| COG1320 | Multisubunit Na+/H+ antiporter, MnhG subunit |
| COG1324 | Uncharacterized protein involved in tolerance to divalent cations |
| COG1348 | Nitrogenase subunit NifH (ATPase) |
| COG1392 | Phosphate transport regulator (distant homolog of PhoU) |
| COG1393 | Arsenate reductase and related proteins, glutaredoxin family |
| COG1464 | ABC-type metal ion transport system, periplasmic component/surface antigen |
| COG1513 | Cyanate lyase |
| COG1528 | Ferritin-like protein |
| COG1553 | Uncharacterized conserved protein involved in intracellular sulfur reduction |
| COG1563 | Predicted subunit of the Multisubunit Na+/H+ antiporter |
| COG1613 | ABC-type sulfate transport system, periplasmic component |
| COG1629 | Outer membrane receptor proteins, mostly Fe transport |
| COG1668 | ABC-type Na+ efflux pump, permease component |
| COG1785 | Alkaline phosphatase |
| COG1824 | Permease, similar to cation transporters |
| COG1840 | ABC-type Fe3+ transport system, periplasmic component |
| COG1858 | Cytochrome c peroxidase |
| COG1863 | Multisubunit Na+/H+ antiporter, MnhE subunit |
| COG1910 | Periplasmic molybdate-binding protein/domain |
| COG1914 | Mn2+ and Fe2+ transporters of the NRAMP family |
| COG1918 | Fe2+ transport system protein A |
| COG1930 | ABC-type cobalt transport system, periplasmic component |
| COG1965 | Protein implicated in iron transport, frataxin homolog |
| COG2011 | ABC-type metal ion transport system, permease component |
| COG2032 | Cu/Zn superoxide dismutase |
| COG2046 | ATP sulfurylase (sulfate adenylyltransferase) |
| COG2059 | Chromate transport protein ChrA |
| COG2060 | K+-transporting ATPase, A chain |
| COG2072 | Predicted flavoprotein involved in K+ transport |
| COG2076 | Membrane transporters of cations and cationic drugs |
| COG2111 | Multisubunit Na+/H+ antiporter, MnhB subunit |
| COG2116 | Formate/nitrite family of transporters |
| COG2146 | Ferredoxin subunits of nitrite reductase and ring-hydroxylating dioxygenases |
| COG2156 | K+-transporting ATPase, c chain |
| COG2168 | Uncharacterized conserved protein involved in oxidation of intracellular sulfur |
| COG2193 | Bacterioferritin (cytochrome b1) |
| COG2212 | Multisubunit Na+/H+ antiporter, MnhF subunit |
| COG2216 | High-affinity K+ transport system, ATPase chain B |
| COG2217 | Cation transport ATPase |
| COG2223 | Nitrate/nitrite transporter |
| COG2239 | Mg/Co/Ni transporter MgtE (contains CBS domain) |
| COG2375 | Siderophore-interacting protein |
| COG2382 | Enterochelin esterase and related enzymes |
| COG2608 | Copper chaperone |
| COG2703 | Hemerythrin |
| COG2807 | Cyanate permease |
| COG2822 | Predicted periplasmic lipoprotein involved in iron transport |
| COG2824 | Uncharacterized Zn-ribbon-containing protein involved in phosphonate metabolism |
| COG2837 | Predicted iron-dependent peroxidase |
| COG2895 | GTPases - Sulfate adenylate transferase subunit 1 |
| COG2897 | Rhodanese-related sulfurtransferase |
| COG2906 | Bacterioferritin-associated ferredoxin |
| COG2920 | Dissimilatory sulfite reductase (desulfoviridin), gamma subunit |
| COG2923 | Uncharacterized protein involved in the oxidation of intracellular sulfur |
| COG2967 | Uncharacterized protein affecting Mg2+/Co2+ transport |
| COG3004 | Na+/H+ antiporter |
| COG3015 | Uncharacterized lipoprotein NlpE involved in copper resistance |
| COG3062 | Uncharacterized protein involved in formation of periplasmic nitrate reductase |
| COG3067 | Na+/H+ antiporter |
| COG3119 | Arylsulfatase A and related enzymes |
| COG3131 | Periplasmic glucans biosynthesis protein |
| COG3142 | Uncharacterized protein involved in copper resistance |
| COG3158 | K+ transporter |
| COG3197 | Uncharacterized protein, possibly involved in nitrogen fixation |
| COG3213 | Uncharacterized protein involved in response to NO |
| COG3221 | ABC-type phosphate/phosphonate transport system, periplasmic component |
| COG3230 | Heme oxygenase |
| COG3256 | Nitric oxide reductase large subunit |
| COG3263 | NhaP-type Na+/H+ and K+/H+ antiporters with a unique C-terminal domain |
| COG3301 | Formate-dependent nitrite reductase, membrane component |
| COG3303 | Formate-dependent nitrite reductase, periplasmic cytochrome c552 subunit |
| COG3338 | Carbonic anhydrase |
| COG3376 | High-affinity nickel permease |
| COG3420 | Nitrous oxidase accessory protein |
| COG3454 | Metal-dependent hydrolase involved in phosphonate metabolism |
| COG3470 | Uncharacterized protein probably involved in high-affinity Fe2+ transport |
| COG3487 | Uncharacterized iron-regulated protein |
| COG3540 | Phosphodiesterase/alkaline phosphatase D |
| COG3546 | Mn-containing catalase |
| COG3615 | Uncharacterized protein/domain, possibly involved in tellurite resistance |
| COG3624 | Uncharacterized enzyme of phosphonate metabolism |
| COG3625 | Uncharacterized enzyme of phosphonate metabolism |
| COG3626 | Uncharacterized enzyme of phosphonate metabolism |
| COG3627 | Uncharacterized enzyme of phosphonate metabolism |
| COG3638 | ABC-type phosphate/phosphonate transport system, ATPase component |
| COG3639 | ABC-type phosphate/phosphonate transport system, permease component |
| COG3667 | Uncharacterized protein involved in copper resistance |
| COG3678 | P pilus assembly/Cpx signaling pathway, periplasmic inhibitor/zinc-resistance associated protein |
| COG3696 | Putative silver efflux pump |
| COG3703 | Uncharacterized protein involved in cation transport |
| COG3709 | Uncharacterized component of phosphonate metabolism |
| COG3712 | Fe2+-dicitrate sensor, membrane component |
| COG3720 | Putative heme degradation protein |
| COG3721 | Putative heme iron utilization protein |
| COG3746 | Phosphate-selective porin |
| COG3793 | Tellurite resistance protein |
| COG3853 | Uncharacterized protein involved in tellurite resistance |
| COG3965 | Predicted Co/Zn/Cd cation transporters |
| COG4097 | Predicted ferric reductase |
| COG4100 | Cystathionine beta-lyase family protein involved in aluminum resistance |
| COG4107 | ABC-type phosphonate transport system, ATPase component |
| COG4148 | ABC-type molybdate transport system, ATPase component |
| COG4149 | ABC-type molybdate transport system, permease component |
| COG4150 | ABC-type sulfate transport system, periplasmic component |
| COG4208 | ABC-type sulfate transport system, permease component |
| COG4242 | Cyanophycinase and related exopeptidases |
| COG4256 | Hemin uptake protein |
| COG4300 | Predicted permease, cadmium resistance protein |
| COG4362 | Nitric oxide synthase, oxygenase domain |
| COG4454 | Uncharacterized copper-binding protein |
| COG4521 | ABC-type taurine transport system, periplasmic component |
| COG4525 | ABC-type taurine transport system, ATPase component |
| COG4531 | ABC-type Zn2+ transport system, periplasmic component/surface adhesin |
| COG4535 | Putative Mg2+ and Co2+ transporter CorC |
| COG4536 | Putative Mg2+ and Co2+ transporter CorB |
| COG4548 | Nitric oxide reductase activation protein |
| COG4555 | ABC-type Na+ transport system, ATPase component |
| COG4558 | ABC-type hemin transport system, periplasmic component |
| COG4559 | ABC-type hemin transport system, ATPase component |
| COG4592 | ABC-type Fe2+-enterobactin transport system, periplasmic component |
| COG4594 | ABC-type Fe3+-citrate transport system, periplasmic component |
| COG4604 | ABC-type enterochelin transport system, ATPase component |
| COG4605 | ABC-type enterochelin transport system, permease component |
| COG4606 | ABC-type enterochelin transport system, permease component |
| COG4607 | ABC-type enterochelin transport system, periplasmic component |
| COG4615 | ABC-type siderophore export system, fused ATPase and permease components |
| COG4638 | Phenylpropionate dioxygenase and related ring-hydroxylating dioxygenases, large terminal subunit |
| COG4651 | Kef-type K+ transport system, predicted NAD-binding component |
| COG4771 | Outer membrane receptor for ferrienterochelin and colicins |
| COG4772 | Outer membrane receptor for Fe3+-dicitrate |
| COG4773 | Outer membrane receptor for ferric coprogen and ferric-rhodotorulic acid |
| COG4774 | Outer membrane receptor for monomeric catechols |
| COG4778 | ABC-type phosphonate transport system, ATPase component |
| COG4779 | ABC-type enterobactin transport system, permease component |
| COG4985 | ABC-type phosphate transport system, auxiliary component |
| COG4986 | ABC-type anion transport system, duplicated permease component |
| COG5036 | SPX domain-containing protein involved in vacuolar polyphosphate accumulation |
| COG5065 | Protein involved in inorganic phosphate transport |
| COG5266 | ABC-type Co2+ transport system, periplasmic component |
| COG5398 | Heme oxygenase |
| COG5456 | Predicted integral membrane protein linked to a cation pump |
