title: Catabolism of 4-hydroxybenzoate in Candida parapsilosis proceeds through initial oxidative decarboxylation by a FAD-dependent 4-hydroxybenzoate 1-hydroxylase.
abstract: The first two steps in the catabolism of 4-hydroxybenzoate by the ascomycetous yeast Candida parapsilosis CBS604 were investigated. In contrast to the well-known bacterial pathways and to what was previously assumed, metabolism of 4-hydroxybenzoate in C. parapsilosis proceeds through initial oxidative decarboxylation to give 1,4-dihydroxybenzene. This reaction is catalyzed by a NAD(P)H and FAD-dependent 4-hydroxybenzoate 1-hydroxylase. Further metabolism of 1,4-dihydroxybenzene to the ring-fission substrate 1,2,4-trihydroxybenzene is catalyzed by a NADPH-specific FAD-dependent aromatic hydroxylase acting on phenolic compounds. 19F-NMR experiments with cell extracts and 2-fluoro-4-hydroxybenzoate as the model compound confirm this metabolic pathway and exclude the alternative pathway proceeding through initial 3-hydroxylation followed by oxidative decarboxylation in the second step.
authors.affiliation: Department of Biochemistry, Agricultural University, Wageningen, The Netherlands.
authors.forename: W J
authors.initials: WJ
authors.lastname: van Berkel
authors.forename: M H
authors.initials: MH
authors.lastname: Eppink
authors.forename: W J
authors.initials: WJ
authors.lastname: Middelhoven
authors.forename: J
authors.initials: J
authors.lastname: Vervoort
authors.forename: I M
authors.initials: IM
authors.lastname: Rietjens
mesh_terms: D015109:4-Hydroxybenzoate-3-Monooxygenase / Q000378:metabolism*; D002175:Candida / Q000201:enzymology* / Q000378:metabolism; D003653:Decarboxylation; D005182:Flavin-Adenine Dinucleotide / Q000378:metabolism*; D010226:Parabens / Q000378:metabolism*
chemical_list: D010226:Parabens; D005182:Flavin-Adenine Dinucleotide; D015109:4-Hydroxybenzoate-3-Monooxygenase; C038193:4-hydroxybenzoic acid