gedI

Probable decarboxylase gedI

313 amino acids

Probable decarboxylase; part of the gene cluster that mediates the biosynthesis of geodin, an intermediate in the biosynthesis of other natural products (PubMed:7665560, PubMed:19549600, PubMed:24009710). The pathway begins with the synthesis of atrochrysone thioester by the polyketide synthase (PKS) gedC (PubMed:12536215, PubMed:19549600). The atrochrysone carboxyl ACP thioesterase gedB then breaks the thioester bond and releases the atrochrysone carboxylic acid from gedC (PubMed:19549600). The atrochrysone carboxylic acid is then converted to atrochrysone which is further transformed into emodin anthrone (PubMed:24009710). The next step is performed by the emodinanthrone oxygenase gedH that catalyzes the oxidation of emodinanthrone to emodin (PubMed:1810248). Emodin O-methyltransferase encoded probably by gedA then catalyzes methylation of the 8-hydroxy group of emodin to form questin (PubMed:1444712). Questin oxidase is then involved in the ring cleavage of questin to form desmethylsulochrin via several intermediates including questin epoxide (PubMed:3182756). Another methylation step probably catalyzed by one of the methyltransferases identified in the cluster leads to the formation of sulochrin which is further converted to dihydrogeodin by the sulochrin halogenase gedL (PubMed:24009710). Finally, the dihydrogeodin oxidase gedJ catalyzes the stereospecific phenol oxidative coupling reaction converting dihydrogeodin to geodin (PubMed:7665560).

Belongs to the tpcK family.

35.205 kDa

MKLEQCIVGRDHTDPRKWHHGDGRDGREHRTAPGLVGGSLAGRDPPVERARGDGDGGHEFMSVVVEGGELREQLLGLRIGIEEDRHRDERQAHHRPYRRSTRCTAGSLYIGDFIAGRTTVVGAIGAGPPSQRRFAFPEVNDCGPSSNIFAKCCAPGTILFGNIFDLPNFPRMSDVRAGSNDPPGKYLCLTICGYRKPGMSEEDYRHHMTKISAPMTKDLMVKYGIKRWTMIHSPAVTRTLMDQLYDSQMVNLADFDCFSQVVFKSVEDYKRMKEDPYYKEHLFKDHEHFADTKKSLFVHFMPLPPPLGPCPGS