title: Identification of a Polyketide Synthase Gene in the Synthesis of Phleichrome of the Phytopathogenic Fungus Cladosporium phlei.
abstract: Phleichrome, a pigment produced by the phytopathogenic fungus Cladosporium phlei, is a fungal perylenequinone whose photodynamic activity has been studied intensively. To determine the biological function of phleichrome and to engineer a strain with enhanced production of phleichrome, we identified the gene responsible for the synthesis of phleichrome. Structural comparison of phleichrome with other fungal perylenequinones suggested that phleichrome is synthesized via polyketide pathway. We recently identified four different polyketide synthase (PKS) genes encompassing three major clades of fungal PKSs that differ with respect to reducing conditions for the polyketide product. Based on in silico analysis of cloned genes, we hypothesized that the non-reducing PKS gene, Cppks1, is involved in phleichrome biosynthesis. Increased accumulation of Cppks1 transcript was observed in response to supplementation with the application of synthetic inducer cyclo-(l-Pro-l-Phe). In addition, heterologous expression of the Cppks1 gene in Cryphonectria parasitica resulted in the production of phleichrome. These results provide convincing evidence that the Cppks1 gene is responsible for the biosynthesis of phleichrome.
authors.affiliation: Institute for Molecular Biology and Genetics, Chonbuk National University, Jeonju 561-756, Korea.
authors.forename: Kum-Kang
authors.initials: KK
authors.lastname: So
authors.affiliation: Physical Lab., Center for University-wide Research Facilities, Chonbuk National University, Jeonju 561-756, Korea.
authors.forename: Yun-Jo
authors.initials: YJ
authors.lastname: Chung
authors.affiliation: Department of Bio-Environmental Chemistry, Institute of Life Science and Natural Resources, Wonkwang University, Iksan 570-749, Korea.
authors.forename: Jung-Mi
authors.initials: JM
authors.lastname: Kim
authors.affiliation: Research Center of Bioactive Materials, Chonbuk National University, Jeonju 561-756, Korea.
authors.forename: Beom-Tae
authors.initials: BT
authors.lastname: Kim
authors.affiliation: Institute for Molecular Biology and Genetics, Chonbuk National University, Jeonju 561-756, Korea.
authors.forename: Seung-Moon
authors.initials: SM
authors.lastname: Park
authors.affiliation: Institute for Molecular Biology and Genetics, Chonbuk National University, Jeonju 561-756, Korea.
authors.forename: Dae-Hyuk
authors.initials: DH
authors.lastname: Kim
mesh_terms: D002963:Cladosporium / Q000201:enzymology* / Q000235:genetics; D003001:Cloning, Molecular; D003198:Computer Simulation; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D009281:Naphthalenes / Q000737:chemistry / Q000378:metabolism*; D010802:Phylogeny; D048630:Polyketide Synthases / Q000235:genetics* / Q000378:metabolism
chemical_list: D005656:Fungal Proteins; D009281:Naphthalenes; D048630:Polyketide Synthases; C061463:calphostin D
keywords: Cladosporium phlei; Cryphonectria parasitica; heterologous expression; phleichrome; polyketide synthase