title: Genome mining reveals the presence of a conserved gene cluster for the biosynthesis of ergot alkaloid precursors in the fungal family Arthrodermataceae.
abstract: Genome sequence analysis of different fungi of the family Arthrodermataceae revealed the presence of a gene cluster consisting of five genes with high sequence similarity to those involved in the early common steps of ergot alkaloid biosynthesis in Aspergillus fumigatus and Claviceps purpurea. To provide evidence that this cluster is involved in ergot alkaloid biosynthesis, the gene ARB_04646 of the fungus Arthroderma benhamiae was cloned into pQE60 and expressed in Escherichia coli. Enzyme assays with the soluble tetrameric His(6)-tagged protein proved unequivocally that the deduced gene product, here termed ChaDH, catalysed the oxidation of chanoclavine-I in the presence of NAD(+), resulting in the formation of chanoclavine-I aldehyde. The enzyme product was unequivocally proven by NMR and MS analyses. Therefore, ChaDH functions as a chanoclavine-I dehydrogenase. K(m) values for chanoclavine-I and NAD(+) were 0.09 and 0.36 mM, respectively. Turnover number was 0.76 s(-1).
authors.affiliation: Philipps-Universität Marburg, Institut für Pharmazeutische Biologie und Biotechnologie, Deutschhausstraße 17a, 35037 Marburg, Germany.
authors.forename: Christiane
authors.initials: C
authors.lastname: Wallwey
authors.affiliation: Abteilung für Molekulare und Angewandte Mikrobiologie, Leibniz-Institut für Naturstoff-Forschung und Infektionsbiologie e.V.-Hans-Knöll-Institut (HKI), Beutenbergstraße 11a, 07745 Jena, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Heddergott
authors.affiliation: Philipps-Universität Marburg, Fachbereich Chemie, Hans-Meerwein-Straße, 35032 Marburg, Germany.
authors.forename: Xiulan
authors.initials: X
authors.lastname: Xie
authors.affiliation: Institut für Mikrobiologie, Friedrich-Schiller-Universität Jena, Philosophenweg 12, 07743 Jena, Germany.|Abteilung für Molekulare und Angewandte Mikrobiologie, Leibniz-Institut für Naturstoff-Forschung und Infektionsbiologie e.V.-Hans-Knöll-Institut (HKI), Beutenbergstraße 11a, 07745 Jena, Germany.
authors.forename: Axel A
authors.initials: AA
authors.lastname: Brakhage
authors.affiliation: Philipps-Universität Marburg, Institut für Pharmazeutische Biologie und Biotechnologie, Deutschhausstraße 17a, 35037 Marburg, Germany.
authors.forename: Shu-Ming
authors.initials: SM
authors.lastname: Li
mesh_terms: D003883:Arthrodermataceae / Q000737:chemistry / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D001232:Aspergillus fumigatus / Q000737:chemistry / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D017124:Conserved Sequence; D004876:Ergot Alkaloids / Q000096:biosynthesis*; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D016681:Genome, Fungal; D008969:Molecular Sequence Data; D005810:Multigene Family; D010088:Oxidoreductases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D004876:Ergot Alkaloids; D005656:Fungal Proteins; D010088:Oxidoreductases