title: Characterization of a Biflaviolin Synthase CYP158A3 fromStreptomyces avermitilisand Its Role in the Biosynthesis of Secondary Metabolites.
abstract: Streptomyces avermitilisproduces clinically useful drugs such as avermectins and oligomycins. Its genome contains approximately 33 cytochrome P450 genes and they seem to play important roles in the biosynthesis of many secondary metabolites. TheSAV_7130gene fromS. avermitilisencodes CYP158A3. The amino acid sequence of this enzyme has high similarity with that of CYP158A2, a biflaviolin synthase fromS. coelicolorA3(2). RecombinantS. avermitilisCYP158A3 was heterologously expressed and purified. It exhibited the typical P450 Soret peak at 447 nm in the reduced CO-bound form. Type I binding spectral changes were observed when CYP158A3 was titrated with myristic acid; however, no oxidative product was formed. An analog of flaviolin, 2-hydroxynaphthoquinone (2-OH NQ) displayed similar type I binding upon titration with purified CYP158A3. It underwent an enzymatic reaction forming dimerized product. A homology model of CYP158A3 was superimposed with the structure of CYP158A2, and the majority of structural elements aligned. These results suggest that CYP158A3 might be an orthologue of biflaviolin synthase, catalyzing C-C coupling reactions during pigment biosynthesis inS. avermitilis.
authors.affiliation: Department of Biological Sciences, Konkuk University, Seoul 05025, Republic of Korea.
authors.forename: Young-Ran
authors.initials: YR
authors.lastname: Lim
authors.affiliation: Department of Biological Sciences, Konkuk University, Seoul 05025, Republic of Korea.
authors.forename: Songhee
authors.initials: S
authors.lastname: Han
authors.affiliation: Department of Biological Sciences, Konkuk University, Seoul 05025, Republic of Korea.
authors.forename: Joo-Hwan
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Biological Sciences, Konkuk University, Seoul 05025, Republic of Korea.
authors.forename: Hyoung-Goo
authors.initials: HG
authors.lastname: Park
authors.affiliation: School of Biological Sciences and Technology, Chonnam National University, Gwangju 61186, Republic of Korea.
authors.forename: Ga-Young
authors.initials: GY
authors.lastname: Lee
authors.affiliation: School of Biological Sciences and Technology, Chonnam National University, Gwangju 61186, Republic of Korea.
authors.forename: Thien-Kim
authors.initials: TK
authors.lastname: Le
authors.affiliation: School of Biological Sciences and Technology, Chonnam National University, Gwangju 61186, Republic of Korea.
authors.forename: Chul-Ho
authors.initials: CH
authors.lastname: Yun
authors.affiliation: Department of Biological Sciences, Konkuk University, Seoul 05025, Republic of Korea.
authors.forename: Donghak
authors.initials: D
authors.lastname: Kim
keywords: 2-Hydroxynaphthoquinone; CYP158A3; Flaviolin; P450; Streptomyces avermitilis