Intradiol dioxygenases structure

With one exception, in all the substrates the ene-diol structure is part of an aromatic nucleus. Oxidative cleavage of the ene-diol yields a dicarboxylic acid which retains the geometry of the remaining double bonds. There are eight of these so-called intradiol dioxygenases (/, 2, 83). 

Dioxygenase enzymes are known that contain heme iron, nonheme iron, copper, or manganese.The substrates whose oxygenations are catalyzed by these enzymes are very diverse, as are the metal-binding sites so probably several, possibly unrelated, mechanisms operate in these different systems. For many of these enzymes, there is not yet much detailed mechanistic information. However, some of the intradiol catechol dioxygenases isolated from bacterial sources have been studied in great detail, and both structural and mechanistic information is available. These are the systems that will be described here. 

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