title: Transcriptomic study for screening genes involved in the oxidative bioconversions of Streptomyces avermitilis.
abstract: Streptomyces avermitilis is a well known organism producing avermectin antibiotics, and has been utilized as an industrial host for oxidation bioconversion processes. Recently, gene screening strategies related to bioconversions have received much focus, as attempts are made to optimize oxidation and biodegradation pathways to maximize yield and productivity. Here, we have demonstrated the oxidative metabolisms of three molecules, daidzein, p-coumaric acid and mevastatin, where S. avermitilis converted each substrate to 3',4',7-trihydroxyisoflavone, caffeic acid and hydroxyl-mevastatin to yield 9.3, 32.5 and 15.0 %, respectively. Microarray technology was exploited to investigate genome-wide analysis of gene expression changes, which were induced upon the addition of each substrate. Cytochrome P450 hydroxylases (pteC, cyp28 and olmB), diooxygenases (xylE, cdo1 and putatives) and LuxAB-like oxygenase were identified. One of them, cyp28, was indeed a gene encoding P450 hydroxylase responsible for the oxidative reaction of daidzein. Furthermore, possible electron transfer chain (fdrC → pteE → pteC) supporting cytochrome P450 dependent hydroxylation of daidzein has been suggested based on the interpretation of expression profiles. The result provided a potential application of transcriptomic study on uncovering enzymes involved in oxidative bioconversions of S. avermitilis.
authors.affiliation: Department of Chemical and Biological Engineering, Korea University, Seongbuk-gu, Seoul, 136-713, South Korea.
authors.forename: Hyo-Jeong
authors.initials: HJ
authors.lastname: Kim
authors.forename: Kwon-Young
authors.initials: KY
authors.lastname: Choi
authors.forename: Da-Hye
authors.initials: DH
authors.lastname: Jung
authors.forename: Joon-Young
authors.initials: JY
authors.lastname: Jung
authors.forename: Eunok
authors.initials: E
authors.lastname: Jung
authors.forename: Yung-Hun
authors.initials: YH
authors.lastname: Yang
authors.forename: Byung-Gee
authors.initials: BG
authors.lastname: Kim
authors.forename: Min-Kyu
authors.initials: MK
authors.lastname: Oh
mesh_terms: D001673:Biodegradation, Environmental; D003373:Coumaric Acids / Q000378:metabolism; D008401:Gas Chromatography-Mass Spectrometry; D020869:Gene Expression Profiling; D005798:Genes, Bacterial; D007529:Isoflavones / Q000378:metabolism; D008148:Lovastatin / Q000031:analogs & derivatives / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D010084:Oxidation-Reduction; D010802:Phylogeny; D011422:Propionates; D013302:Streptomyces / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D059467:Transcriptome
chemical_list: D003373:Coumaric Acids; D007529:Isoflavones; D011422:Propionates; C012258:mevastatin; C004742:daidzein; D008148:Lovastatin; C495469:p-coumaric acid