Solanapyrone synthase, a possible Diels-Alderase and iterative type I polyketide synthase encoded in a biosynthetic gene cluster from Alternaria solani.
The solanapyrone biosynthetic gene cluster was cloned from Alternaria solani. It consists of six genes-sol1-6-coding for a polyketide synthase, an O-methyltransferase, a dehydrogenase, a transcription factor, a flavin-dependent oxidase, and cytochrome P450. The prosolanapyrone synthase (PSS) encoded by sol1 was expressed in Aspergillus oryzae and its product was identified as desmethylprosolanapyrone I (8). Although PSS is closely related to the PKSs/Diels-Alderases LovB and MlcA of lovastatin and compactin biosynthesis, it did not catalyze cycloaddition. Sol5, encoding a flavin-dependent oxidase (solanapyrone synthase, SPS), was expressed in Pichia pastoris and purified. The purified recombinant SPS showed activity for the formation of (-)-solanapyrone A (1) from achiral prosolanapyrone II (2), establishing that this single enzyme catalyzes both the oxidation and the subsequent cycloaddition reaction, possibly as a Diels-Alder enzyme.
Kasahara
Ken
K
Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Miyamoto
Takanori
T
Fujimoto
Takashi
T
Oguri
Hiroki
H
Tokiwano
Tetsuo
T
Oikawa
Hideaki
H
Ebizuka
Yutaka
Y
Fujii
Isao
I
D000528:Alternaria / Q000201:enzymology*; D055162:Biocatalysis; D002942:Circular Dichroism; D003500:Cyclization; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D019746:Intramolecular Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D005810:Multigene Family; D009281:Naphthalenes / Q000737:chemistry / Q000378:metabolism; D010084:Oxidation-Reduction; D048630:Polyketide Synthases / Q000235:genetics / Q000378:metabolism*; D011753:Pyrones / Q000737:chemistry / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D013237:Stereoisomerism
D005656:Fungal Proteins; D009281:Naphthalenes; D011753:Pyrones; D011994:Recombinant Proteins; D048630:Polyketide Synthases; C113266:solanapyrone A; D019746:Intramolecular Oxidoreductases; C113265:solanapyrone synthase