The Enzyme Database

Your query returned 12 entries.    printer_iconPrintable version

Accepted name: alcohol dehydrogenase (azurin)
Reaction: a primary alcohol + azurin = an aldehyde + reduced azurin
Other name(s): type II quinoprotein alcohol dehydrogenase; quinohaemoprotein ethanol dehydrogenase; QHEDH; ADHIIB
Systematic name: alcohol:azurin oxidoreductase
Comments: A soluble, periplasmic PQQ-containing quinohemoprotein. Also contains a single heme c. Occurs in Comamonas and Pseudomonas. Does not require an amine activator. Oxidizes a wide range of primary and secondary alcohols, and also aldehydes and large substrates such as sterols; methanol is not a substrate. Usually assayed with phenazine methosulfate or ferricyanide. Like all other quinoprotein alcohol dehydrogenases it has an 8-bladed ‘propeller’ structure, a calcium ion bound to the PQQ in the active site and an unusual disulfide ring structure in close proximity to the PQQ.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc
1.  Groen, B.W., van Kleef, M.A. and Duine, J.A. Quinohaemoprotein alcohol dehydrogenase apoenzyme from Pseudomonas testosteroni. Biochem. J. 234 (1986) 611–615. [PMID: 3521592]
2.  de Jong, G.A., Caldeira, J., Sun, J., Jongejan, J.A., de Vries, S., Loehr, T.M., Moura, I., Moura, J.J. and Duine, J.A. Characterization of the interaction between PQQ and heme c in the quinohemoprotein ethanol dehydrogenase from Comamonas testosteroni. Biochemistry 34 (1995) 9451–9458. [PMID: 7626615]
3.  Toyama, H., Fujii, A., Matsushita, K., Shinagawa, E., Ameyama, M. and Adachi, O. Three distinct quinoprotein alcohol dehydrogenases are expressed when Pseudomonas putida is grown on different alcohols. J. Bacteriol. 177 (1995) 2442–2450. [DOI] [PMID: 7730276]
4.  Matsushita, K., Yamashita, T., Aoki, N., Toyama, H. and Adachi, O. Electron transfer from quinohemoprotein alcohol dehydrogenase to blue copper protein azurin in the alcohol oxidase respiratory chain of Pseudomonas putida HK5. Biochemistry 38 (1999) 6111–6118. [DOI] [PMID: 10320337]
5.  Chen, Z.W., Matsushita, K., Yamashita, T., Fujii, T.A., Toyama, H., Adachi, O., Bellamy, H.D. and Mathews, F.S. Structure at 1.9 Å resolution of a quinohemoprotein alcohol dehydrogenase from Pseudomonas putida HK5. Structure 10 (2002) 837–849. [DOI] [PMID: 12057198]
6.  Oubrie, A., Rozeboom, H.J., Kalk, K.H., Huizinga, E.G. and Dijkstra, B.W. Crystal structure of quinohemoprotein alcohol dehydrogenase from Comamonas testosteroni: structural basis for substrate oxidation and electron transfer. J. Biol. Chem. 277 (2002) 3727–3732. [DOI] [PMID: 11714714]
[EC created 2010 as EC; transferred 2011 to EC]
Transferred entry: Now EC, alcohol dehydrogenase (azurin)
[EC created 2010, deleted 2011]
Accepted name: aralkylamine dehydrogenase (azurin)
Reaction: ArCH2NH2 + H2O + 2 azurin = ArCHO + NH3 + 2 reduced azurin
Glossary: azurin = an electron-transfer protein containing a type-1 copper site
Other name(s): aromatic amine dehydrogenase; arylamine dehydrogenase; tyramine dehydrogenase; aralkylamine:(acceptor) oxidoreductase (deaminating)
Systematic name: aralkylamine:azurin oxidoreductase (deaminating)
Comments: Phenazine methosulfate can act as acceptor. Acts on aromatic amines and, more slowly, on some long-chain aliphatic amines, but not on methylamine or ethylamine
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc
1.  Iwaki, M., Yagi, T., Horiike, K., Saeki, Y., Ushijima, T. and Nozaki, M. Crystallization and properties of aromatic amine dehydrogenase from Pseudomonas sp. Arch. Biochem. Biophys. 220 (1983) 253–262. [DOI] [PMID: 6830237]
2.  Hyun, Y.L. and Davidson, V.L. Electron transfer reactions between aromatic amine dehydrogenase and azurin. Biochemistry 34 (1995) 12249–12254. [PMID: 7547967]
3.  Hyun, Y.L., Zhu, Z. and Davidson, V.L. Gated and ungated electron transfer reactions from aromatic amine dehydrogenase to azurin. J. Biol. Chem. 274 (1999) 29081–29086. [DOI] [PMID: 10506161]
4.  Davidson, V.L. Electron transfer in quinoproteins. Arch. Biochem. Biophys. 428 (2004) 32–40. [DOI] [PMID: 15234267]
5.  Sukumar, N., Chen, Z.W., Ferrari, D., Merli, A., Rossi, G.L., Bellamy, H.D., Chistoserdov, A., Davidson, V.L. and Mathews, F.S. Crystal structure of an electron transfer complex between aromatic amine dehydrogenase and azurin from Alcaligenes faecalis. Biochemistry 45 (2006) 13500–13510. [DOI] [PMID: 17087503]
[EC created 1986 as EC, transferred 2011 to EC]
Transferred entry: aralkylamine dehydrogenase. Now EC, aralkylamine dehydrogenase (azurin)
[EC created 1986, deleted 2011]
Accepted name: nitrite reductase (NO-forming)
Reaction: nitric oxide + H2O + ferricytochrome c = nitrite + ferrocytochrome c + 2 H+
Glossary: nitric oxide = NO = nitrogen(II) oxide
Other name(s): cd-cytochrome nitrite reductase; [nitrite reductase (cytochrome)] [misleading, see comments.]; cytochrome c-551:O2, NO2+ oxidoreductase; cytochrome cd; cytochrome cd1; hydroxylamine (acceptor) reductase; methyl viologen-nitrite reductase; nitrite reductase (cytochrome; NO-forming)
Systematic name: nitric-oxide:ferricytochrome-c oxidoreductase
Comments: The reaction is catalysed by two types of enzymes, found in the perimplasm of denitrifying bacteria. One type comprises proteins containing multiple copper centres, the other a heme protein, cytochrome cd1. Acceptors include c-type cytochromes such as cytochrome c-550 or cytochrome c-551 from Paracoccus denitrificans or Pseudomonas aeruginosa, and small blue copper proteins such as azurin and pseudoazurin. Cytochrome cd1 also has oxidase and hydroxylamine reductase activities. May also catalyse the reaction of hydroxylamine reductase (EC since this is a well-known activity of cytochrome cd1.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, UM-BBD, CAS registry number: 9080-03-9
1.  Miyata, M. and Mori, T. Studies on denitrification. X. The "denitrifying enzyme" as a nitrite reductase and the electron donating system for denitrification. J. Biochem. (Tokyo) 66 (1969) 463–471. [PMID: 5354021]
2.  Chung, C.W. and Najjar, V.A. Cofactor requirements for enzymatic denitrification. I. Nitrite reductase. J. Biol. Chem. 218 (1956) 617–625. [PMID: 13295215]
3.  Walker, G.C. and Nicholas, D.J.D. Nitrite reductase from Pseudomonas aeruginosa. Biochim. Biophys. Acta 49 (1961) 350–360. [DOI] [PMID: 13782716]
4.  Singh, J. Cytochrome oxidase from Pseudomonas aeruginosa. III. Reduction of hydroxylamine. Biochim. Biophys. Acta 333 (1974) 28–36. [PMID: 19396990]
5.  Michalski, W.P. and Nicholas, D.J.D. Molecular characterization of a copper-containing nitrite reductase from Rhodopseudomonas sphaeriodes forma sp. Denitrificans. Biochim. Biophys. Acta 828 (1985) 130–137.
6.  Godden, J.W., Turley, S., Teller, D.C., Adman, E.T., Liu, M.Y., Payne, W.J. and Legall, J. The 2.3 angstrom X-ray structure of nitrite reductase from Achromobacter cycloclastes. Science 253 (1991) 438–442. [DOI] [PMID: 1862344]
7.  Williams, P.A., Fulop, V., Leung, Y.C., Chan, C., Moir, J.W.B., Howlett, G., Ferguson, S.J., Radford, S.E. and Hajdu, J. Pseudospecific docking surfaces on electron transfer proteins as illustrated by pseudoazurin, cytochrome c-550 and cytochrome cd1 nitrite reductase. Nat. Struct. Biol. 2 (1995) 975–982. [PMID: 7583671]
8.  Hole, U.H., Vollack, K.U., Zumft, W.G., Eisenmann, E., Siddiqui, R.A., Friedrich, B. and Kroneck, P.M.H. Characterization of the membranous denitrification enzymes nitrite reductase (cytochrome cd1) and copper-containing nitrous oxide reductase from Thiobacillus denitrificans. Arch. Microbiol. 165 (1996) 55–61. [PMID: 8639023]
9.  Zumft, W.G. Cell biology and molecular basis of denitrification. Microbiol. Mol. Biol. Rev. 61 (1997) 533–616. [PMID: 9409151]
10.  Ferguson, S.J. Nitrogen cycle enzymology. Curr. Opin. Chem. Biol. 2 (1998) 182–193. [DOI] [PMID: 9667932]
11.  Vijgenboom, E., Busch, J.E. and Canters, G.W. In vitro studies disprove the obligatory role of azurin in denitrification in Pseudomonas aeruginosa and show that azu expression is under the control of RpoS and ANR. Microbiology 143 (1997) 2853–2863. [DOI] [PMID: 9308169]
[EC created 1961, modified 1976, modified 2001, modified 2002 (EC created 1961 as EC, transferred 1964 to EC, modified 1976, incorporated 2002, EC created 1965, incorporated 2002)]
Transferred entry: hydroxylamine oxidase. Now covered by EC, hydroxylamine dehydrogenase, and EC, hydroxylamine oxidase (cytochrome)
[EC created 1972, deleted 2013]
Accepted name: hydroxylamine oxidase (cytochrome)
Reaction: hydroxylamine + O2 = nitrite + H2O + H+ (overall reaction)
(1a) hydroxylamine + 2 ferricytochrome c = nitroxyl + 2 ferrocytochrome c + 2 H+
(1b) nitroxyl + 2 ferrocytochrome c + O2 + H+ = nitrite + 2 ferricytochrome c + H2O (spontaneous)
Other name(s): HAO (ambiguous); hydroxylamine oxidoreductase (ambiguous); hydroxylamine oxidase (misleading)
Systematic name: hydroxylamine:oxygen oxidoreductase
Comments: The enzyme from the heterotrophic nitrifying bacterium Paracoccus denitrificans contains three to five non-heme, non-iron-sulfur iron atoms and interacts with cytochrome c556 and pseudoazurin [2,3]. Under anaerobic conditions in vitro only nitrous oxide is formed [3]. Presumably nitroxyl is released and combines with a second nitroxyl to give nitrous oxide and water. When oxygen is present, nitrite is formed.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9075-43-8
1.  Kurokawa, M, Fukumori, Y and Yamanaka, T A hydroxylamine - cytochrome c reductase occurs in the heterotrophic nitrifier Arthrobacter globiformis. Plant Cell Physiol. 26 (1985) 1439–1442.
2.  Wehrfritz, J.M., Reilly, A., Spiro, S. and Richardson, D.J. Purification of hydroxylamine oxidase from Thiosphaera pantotropha. Identification of electron acceptors that couple heterotrophic nitrification to aerobic denitrification. FEBS Lett. 335 (1993) 246–250. [DOI] [PMID: 8253206]
3.  Moir, J.W., Wehrfritz, J.M., Spiro, S. and Richardson, D.J. The biochemical characterization of a novel non-haem-iron hydroxylamine oxidase from Paracoccus denitrificans GB17. Biochem. J. 319 (1996) 823–827. [PMID: 8920986]
4.  Wehrfritz, J., Carter, J.P., Spiro, S. and Richardson, D.J. Hydroxylamine oxidation in heterotrophic nitrate-reducing soil bacteria and purification of a hydroxylamine-cytochrome c oxidoreductase from a Pseudomonas species. Arch. Microbiol. 166 (1996) 421–424. [PMID: 9082922]
[EC created 1972 as EC, part transferred 2013 to EC, modified 2015]
Accepted name: 4-methylphenol dehydrogenase (hydroxylating)
Reaction: 4-methylphenol + 4 oxidized azurin + H2O = 4-hydroxybenzaldehyde + 4 reduced azurin + 4 H+ (overall reaction)
(1a) 4-methylphenol + 2 oxidized azurin + H2O = 4-hydroxybenzyl alcohol + 2 reduced azurin + 2 H+
(1b) 4-hydroxybenzyl alcohol + 2 oxidized azurin = 4-hydroxybenzaldehyde + 2 reduced azurin + 2 H+
Glossary: 4-methylphenol = 4-cresol = p-cresol
Other name(s): pchCF (gene names); p-cresol-(acceptor) oxidoreductase (hydroxylating); p-cresol methylhydroxylase; 4-cresol dehydrogenase (hydroxylating)
Systematic name: 4-methylphenol:oxidized azurin oxidoreductase (methyl-hydroxylating)
Comments: This bacterial enzyme contains a flavin (FAD) subunit and a cytochrome c subunit. The flavin subunit abstracts two hydrogen atoms from the substrate, forming a quinone methide intermediate, then hydrates the latter at the benzylic carbon with a hydroxyl group derived from water. The protons are lost to the bulk solvent, while the electrons are passed to the heme on the cytochrome subunit, and from there to azurin, a small copper-binding protein that is co-localized with the enzyme in the periplasm. The first hydroxylation forms 4-hydroxybenzyl alcohol; a second hydroxylation converts this into 4-hydroxybenzaldehyde.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, UM-BBD, CAS registry number: 66772-07-4
1.  Hopper, D.J. and Taylor, D.G. The purification and properties of p-cresol-(acceptor) oxidoreductase (hydroxylating), a flavocytochrome from Pseudomonas putida. Biochem. J. 167 (1977) 155–162. [PMID: 588247]
2.  McIntire, W., Edmondson, D.E. and Singer, T.P. 8α-O-Tyrosyl-FAD: a new form of covalently bound flavin from p-cresol methylhydroxylase. J. Biol. Chem. 255 (1980) 6553–6555. [PMID: 7391034]
3.  Hopper, D.J., Jones, M.R. and Causer, M.J. Periplasmic location of p-cresol methylhydroxylase in Pseudomonas putida. FEBS Lett. 182 (1985) 485–488. [PMID: 3920077]
4.  Bossert, I.D., Whited, G., Gibson, D.T. and Young, L.Y. Anaerobic oxidation of p-cresol mediated by a partially purified methylhydroxylase from a denitrifying bacterium. J. Bacteriol. 171 (1989) 2956–2962. [DOI] [PMID: 2722739]
5.  Reeve, C.D., Carver, M.A. and Hopper, D.J. Stereochemical aspects of the oxidation of 4-ethylphenol by the bacterial enzyme 4-ethylphenol methylenehydroxylase. Biochem. J. 269 (1990) 815–819. [PMID: 1697166]
6.  Peters, F., Heintz, D., Johannes, J., van Dorsselaer, A. and Boll, M. Genes, enzymes, and regulation of para-cresol metabolism in Geobacter metallireducens. J. Bacteriol. 189 (2007) 4729–4738. [PMID: 17449613]
7.  Johannes, J., Bluschke, A., Jehmlich, N., von Bergen, M. and Boll, M. Purification and characterization of active-site components of the putative p-cresol methylhydroxylase membrane complex from Geobacter metallireducens. J. Bacteriol. 190 (2008) 6493–6500. [PMID: 18658262]
[EC created 1983 as EC, modified 2001, modified 2011, modified 2015, transferred 2018 to EC]
Accepted name: (+)-pinoresinol hydroxylase
Reaction: (+)-pinoresinol + 2 oxidized azurin + H2O = (+)-6-hydroxypinoresinol + 2 reduced azurin + 2 H+
Other name(s): pinoresinol α-hydroxylase; pinAB (gene names)
Systematic name: (+)-pinoresinol:azurin oxidoreductase
Comments: Contains FAD. This enzyme, characterized from the bacterium Pseudomonas sp. SG-MS2, catalyses the incorporation of an oxygen atom originating from a water molecule into position C-6 of the lignan (+)-pinoresinol. The enzyme consists of a flavoprotein subunit and a c-type cytochrome subunit. Electrons that originate in the substrate are transferred via the FAD cofactor and the cytochrome subunit to the blue-copper protein azurin.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc
1.  Shettigar, M., Balotra, S., Kasprzak, A., Pearce, S.L., Lacey, M.J., Taylor, M.C., Liu, J.W., Cahill, D., Oakeshott, J.G. and Pandey, G. Oxidative catabolism of (+)-pinoresinol is initiated by an unusual flavocytochrome encoded by translationally coupled genes within a cluster of (+)-pinoresinol-coinduced genes in Pseudomonas sp. strain SG-MS2. Appl. Environ. Microbiol. 86 (2020) e00375-20. [PMID: 32198167]
[EC created 2020]
Accepted name: arsenate reductase (cytochrome c)
Reaction: arsenite + H2O + 2 oxidized cytochrome c = arsenate + 2 reduced cytochrome c + 2 H+
Other name(s): arsenite oxidase (ambiguous)
Systematic name: arsenite:cytochrome c oxidoreductase
Comments: A molybdoprotein containing iron-sulfur clusters. Isolated from α-proteobacteria. Unlike EC, arsenate reductase (azurin), it does not use azurin as acceptor.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc
1.  vanden Hoven, R.N. and Santini, J.M. Arsenite oxidation by the heterotroph Hydrogenophaga sp. str. NT-14: the arsenite oxidase and its physiological electron acceptor. Biochim. Biophys. Acta 1656 (2004) 148–155. [DOI] [PMID: 15178476]
2.  Santini, J.M., Kappler, U., Ward, S.A., Honeychurch, M.J., vanden Hoven, R.N. and Bernhardt, P.V. The NT-26 cytochrome c552 and its role in arsenite oxidation. Biochim. Biophys. Acta 1767 (2007) 189–196. [DOI] [PMID: 17306216]
3.  Branco, R., Francisco, R., Chung, A.P. and Morais, P.V. Identification of an aox system that requires cytochrome c in the highly arsenic-resistant bacterium Ochrobactrum tritici SCII24. Appl. Environ. Microbiol. 75 (2009) 5141–5147. [DOI] [PMID: 19525272]
4.  Lieutaud, A., van Lis, R., Duval, S., Capowiez, L., Muller, D., Lebrun, R., Lignon, S., Fardeau, M.L., Lett, M.C., Nitschke, W. and Schoepp-Cothenet, B. Arsenite oxidase from Ralstonia sp. 22: characterization of the enzyme and its interaction with soluble cytochromes. J. Biol. Chem. 285 (2010) 20433–20441. [DOI] [PMID: 20421652]
[EC created 2011]
Accepted name: arsenate reductase (azurin)
Reaction: arsenite + H2O + 2 oxidized azurin = arsenate + 2 reduced azurin + 2 H+
For diagram of arsenate catabolism, click here
Glossary: Azurin is a blue copper protein found in many bacteria, which undergoes oxidation-reduction between Cu(I) and Cu(II), and transfers single electrons between enzymes.
Other name(s): arsenite oxidase (ambiguous)
Systematic name: arsenite:azurin oxidoreductase
Comments: Contains a molybdopterin centre comprising two molybdopterin guanosine dinucleotide cofactors bound to molybdenum, a [3Fe-4S] cluster and a Rieske-type [2Fe-2S] cluster. Isolated from β-proteobacteria. Also uses a c-type cytochrome or O2 as acceptors.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, UM-BBD, CAS registry number: 146907-46-2
1.  Anderson, G.L., Williams, J. and Hille, R. The purification and characterization of arsenite oxidase from Alcaligenes faecalis, a molybdenum-containing hydroxylase. J. Biol. Chem. 267 (1992) 23674–23682. [PMID: 1331097]
2.  Ellis, P.J., Conrads, T., Hille, R. and Kuhn, P. Crystal structure of the 100 kDa arsenite oxidase from Alcaligenes faecalis in two crystal forms at 1.64 Å and 2.03 Å. Structure 9 (2001) 125–132. [DOI] [PMID: 11250197]
[EC created 2001 as EC, transferred 2011 to EC]
Transferred entry: arsenate reductase (azurin). Now EC, arsenate reductase (azurin)
[EC created 2001, deleted 2011]

Data © 2001–2022 IUBMB
Web site © 2005–2022 Andrew McDonald