1.1.2.8 evolution ADHs are categorized into three groups (type I, II, and III ADHs) according to their domain structure and localization. Type I ADHs have molecular and enzymatic properties that are very similar to those of methanol dehydrogenases, MDHs, but they have a low affinity for methanol. Type I ADHs, on the other hand, generally use ethylamine or methylamine as essential activators instead of ammonia -, 742110 1.1.2.8 evolution quinoprotein alcohol dehydrogenase usually occupies PQQ as a cofactor and belongs to the family of PQQ-dependent type I alcohol dehydrogenases, sequence comparisons and phylogenetic tree -, 741733 1.1.2.8 malfunction an exaF mutant is not affected for growth with ethanol -, 742793 1.1.2.8 malfunction inactivation of exaA adversely affects the growth of Azospirillum brasilense on glycerol -, 763204 1.1.2.8 malfunction single deletions of genes coding for PQQ-dependent alcohol dehydrogenases PedE and PedH have only minor effects on growth rates, indicating that Pseudomonas putida strain KT2440 can use both enzymes in a redundant fashion for the metabolization of butanol. Growth of mutants lacking PedE and PedH on n-butanol is significantly impaired, but not completely inhibited, suggesting that additional alcohol dehydrogenases can at least partially complement their function in strain KT2440 -, 743174 1.1.2.8 metabolism butanol is oxidized to butyraldehyde by PedE and PedH and then further oxidized to butyric acid by the aldehyde dehydrogenase PedI. Both enzymes, PedE and PedH, are directly involved in butanol oxidation in Pseudomonas putida KT2440 -, 743174 1.1.2.8 metabolism key enzyme in the ethanol oxidase respiratory chain of acetic acid bacteria -, 763081 1.1.2.8 metabolism the enzyme plays an important role in the catabolism of alcohols in bacteria -, 763204 1.1.2.8 additional information ExaF homology modeling using the crystal structure of the quinoprotein ethanol dehydrogenase QEDH from Pseudomonas aeruginosa, PDB 1FLG, overview. Residues E198, D317, D319, and N275 form the active site. Residue D319 might be necessary for lanthanide coordination next to catalytic aspartate D317 -, 742793 1.1.2.8 additional information the enzyme occurs in active and inactive forms, overview. Active ADHa is brought back by ethanol to its full reduction state, but in inactive ADHi, only one-quarter of the total heme c is reduced, pH dependencies and redox potentials of cofactors, overview -, 725041