FAD-dependent monooxygenase tropB

UniProtKB accession:  B8M9J8

Grouped By:  Matching UniProtKB accession

UniProtKB description:  FAD-dependent monooxygenase; part of the gene cluster that mediates the biosynthesis of the tropolone class of fungal maleic anhydrides (PubMed:22508998, PubMed:24863423, PubMed:31346489). Within the pathway, tropB catalyzes a synthetically challenging asymmetric oxidative dearomatization reaction to convert 3-methylorcinaldehyde into a hydroxycyclohexadione (PubMed:22508998, PubMed:24863423, PubMed:31346489). The pathway begins with the synthesis of 3-methylorcinaldehyde by the non-reducing polyketide synthase (PKS) tropA. 3-methylorcinaldehyde is the substrate for the FAD-dependent monooxygenase tropB to yield a dearomatized hydroxycyclohexadione. The 2-oxoglutarate-dependent dioxygenase tropC then performs the oxidative ring expansion to provide the first tropolone metabolite stipitaldehyde. Trop D converts stipitaldehyde into stipitacetal which is in turn converted to stipitalide by the short-chain dehydrogenase/reductase tropE. The next steps involve tropF, tropG, tropH, tropI and tropJ to form successive tropolone maleic anhydrides including stipitaldehydic, stipitatonic and stipitatic acids (Probable).