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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:dateCreated |
1992-12-14
|
| pubmed:abstractText |
The degradation of aromatic compounds by aerobic bacteria frequently begins with the dihydroxylation of the substrate by nonheme iron-containing dioxygenases. These enzymes consist of two or three soluble proteins that interact to form an electron-transport chain that transfers electrons from reduced nucleotides (NADH) via flavin and [2Fe-2S] redox centers to a terminal dioxygenase. The dioxygenases may be classified in terms of the number of constituent components and the nature of the redox centers. Class I consists of two-component enzymes in which the first protein is a reductase containing both a flavin and a [2Fe-2S] redox center and the second component is the oxygenase; Class II consists of three-component enzymes in which the flavin and [2Fe-2S] redox centers of the reductase are on a separate flavoprotein and ferredoxin, respectively; and Class III consists of three-component enzymes in which the reductase contains both a flavin and [2Fe-2S] redox center but also requires a second [2Fe-2S] center on a ferredoxin for electron transfer to the terminal oxygenase. Further subdivision is based on the the type of flavin (FMN or FAD) in the reductase, the coordination of the [2Fe-2S] center in the ferredoxin, and the number of terminal oxygenase subunits. From the deduced amino acid sequence of several dioxygenases the ligands involved in the coordination of the nucleotides, iron-sulfur centers, and mononuclear nonheme iron active site are proposed. On the basis of their spectroscopic properties and unusually high redox potentials, the [2Fe-2S] clusters of the ferredoxins and terminal oxygenases have been assigned to the class of Rieske-type iron-sulfur proteins. The iron atoms in the Rieske iron-sulfur cluster are coordinated to the protein by two histidine nitrogens and two cysteine sulfurs.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:issn |
0066-4227
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
46
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
277-305
|
| pubmed:dateRevised |
2006-11-15
|
| pubmed:meshHeading | |
| pubmed:year |
1992
|
| pubmed:articleTitle |
The electron-transport proteins of hydroxylating bacterial dioxygenases.
|
| pubmed:affiliation |
Division of Biosphere Sciences, King's College London, United Kingdom.
|
| pubmed:publicationType |
Journal Article,
Review,
Research Support, Non-U.S. Gov't
|