Flavocytochrome substrate specificity

Tyr 143, 36 293 Tyr 254, 36 291-293 NMR spectroscopy, 36 271-272 pH dependence, 36 274-275 primary stmcture, 36 261-263 prosthetic groups structure, 36 258 quaternary structure, 36 261-262 reduction potentials, 36 268-269 short electron transport chain, 36 258-259 site-directed mutagenesis, 36 289-290 substrate specificity, 36 272-274 Flavocytochrome C552 electrochemistry, 36 365-367, 369... 

In addition to these topics, the factors controlling substrate specificity in flavocytochrome i>2 Tvill also be discussed since considerable progress has been made in this area over recent years. This discussion will also... 

Limited amino acid sequence information has shown that long-chain a-hydroxyacid oxidase from rat kidney is also related to these FMN-containing oxidoreductases (55). It is likely that several further members of this family remain to be identified. The flavodehydrogenase domain shows no sequence similarity to the lactate dehydrogenase from bacteria and higher eukaryotes that utilize NAD as a substrate. Yeasts lack such an enzyme and the substrate specificity of flavocytochrome 62 has presumably evolved independently of the NAD-linked dehydrogenases. 

Flavocytochromes 2 2-hydroxyacid dehydrogenases found in the inter-membrane space of yeast mitochondria where they couple oxidation of the substrate to reduction of cytochrome c. Examples include the enzymes from Saccharomyces cerevisiae and Hansenula anomala, both of which are l-lactate dehydrogenases (Chapman et al., 1998), and the enzyme from Rhodotorula graminis which is a L-mandelate dehydrogenase (Ilias et al., 1998). This article will concentrate on the flavocytochrome 2 (L-lactate cytochrome c oxidoreductase) from S. cerevisiae (Bakersi yeast), since this is by far the most studied of these enzymes (Chapman et al., 1991). Therefore, throughout this article, the term flavocytochrome 2 will refer specifically to the enzyme from S. cerevisiae unless otherwise stated. 

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