title: Biphenyl 4-Hydroxylases Involved in Aucuparin Biosynthesis in Rowan and Apple Are Cytochrome P450 736A Proteins.
abstract: Upon pathogen attack, fruit trees such as apple (Malus spp.) and pear (Pyrus spp.) accumulate biphenyl and dibenzofuran phytoalexins, with aucuparin as a major biphenyl compound. 4-Hydroxylation of the biphenyl scaffold, formed by biphenyl synthase (BIS), is catalyzed by a cytochrome P450 (CYP). The biphenyl 4-hydroxylase (B4H) coding sequence of rowan (Sorbus aucuparia) was isolated and functionally expressed in yeast (Saccharomyces cerevisiae). SaB4H was named CYP736A107. No catalytic function of CYP736 was known previously. SaB4H exhibited absolute specificity for 3-hydroxy-5-methoxybiphenyl. In rowan cell cultures treated with elicitor from the scab fungus, transient increases in the SaB4H, SaBIS, and phenylalanine ammonia lyase transcript levels preceded phytoalexin accumulation. Transient expression of a carboxyl-terminal reporter gene construct directed SaB4H to the endoplasmic reticulum. A construct lacking the amino-terminal leader and transmembrane domain caused cytoplasmic localization. Functional B4H coding sequences were also isolated from two apple (Malus × domestica) cultivars. The MdB4Hs were named CYP736A163. When stems of cv Golden Delicious were infected with the fire blight bacterium, highest MdB4H transcript levels were observed in the transition zone. In a phylogenetic tree, the three B4Hs were closest to coniferaldehyde 5-hydroxylases involved in lignin biosynthesis, suggesting a common ancestor. Coniferaldehyde and related compounds were not converted by SaB4H.
authors: Institute of Pharmaceutical Biology (D.S., M.M.G., D.R., T.B., B.L., L.B.) and Institute of Plant Biology (D.K., R.H.), Technische Universität Braunschweig, 38106 Braunschweig, Germany;Plant Pathology, Institute of Integrative Biology, Eidgenössische Technische Hochschule Zürich, 8092 Zurich, Switzerland (C.C., G.A.L.B.); andJulius Kühn-Institute, Federal Research Centre for Cultivated Plants, Institute for Breeding Research on Horticultural and Fruit Crops, 01326 Dresden, Germany (H.F.).
authors: Debabrata
authors: http://orcid.org/0000-0002-2788-119X
authors: D
authors: Sircar
authors: Institute of Pharmaceutical Biology (D.S., M.M.G., D.R., T.B., B.L., L.B.) and Institute of Plant Biology (D.K., R.H.), Technische Universität Braunschweig, 38106 Braunschweig, Germany;Plant Pathology, Institute of Integrative Biology, Eidgenössische Technische Hochschule Zürich, 8092 Zurich, Switzerland (C.C., G.A.L.B.); andJulius Kühn-Institute, Federal Research Centre for Cultivated Plants, Institute for Breeding Research on Horticultural and Fruit Crops, 01326 Dresden, Germany (H.F.).
authors: Mariam M
authors: http://orcid.org/0000-0002-7290-0628
authors: MM
authors: Gaid
authors: Institute of Pharmaceutical Biology (D.S., M.M.G., D.R., T.B., B.L., L.B.) and Institute of Plant Biology (D.K., R.H.), Technische Universität Braunschweig, 38106 Braunschweig, Germany;Plant Pathology, Institute of Integrative Biology, Eidgenössische Technische Hochschule Zürich, 8092 Zurich, Switzerland (C.C., G.A.L.B.); andJulius Kühn-Institute, Federal Research Centre for Cultivated Plants, Institute for Breeding Research on Horticultural and Fruit Crops, 01326 Dresden, Germany (H.F.).
authors: Cornelia
authors: http://orcid.org/0000-0001-9337-4527
authors: C
authors: Chizzali
authors: Institute of Pharmaceutical Biology (D.S., M.M.G., D.R., T.B., B.L., L.B.) and Institute of Plant Biology (D.K., R.H.), Technische Universität Braunschweig, 38106 Braunschweig, Germany;Plant Pathology, Institute of Integrative Biology, Eidgenössische Technische Hochschule Zürich, 8092 Zurich, Switzerland (C.C., G.A.L.B.); andJulius Kühn-Institute, Federal Research Centre for Cultivated Plants, Institute for Breeding Research on Horticultural and Fruit Crops, 01326 Dresden, Germany (H.F.).
authors: Dennis
authors: http://orcid.org/0000-0001-5449-0170
authors: D
authors: Reckwell
authors: Institute of Pharmaceutical Biology (D.S., M.M.G., D.R., T.B., B.L., L.B.) and Institute of Plant Biology (D.K., R.H.), Technische Universität Braunschweig, 38106 Braunschweig, Germany;Plant Pathology, Institute of Integrative Biology, Eidgenössische Technische Hochschule Zürich, 8092 Zurich, Switzerland (C.C., G.A.L.B.); andJulius Kühn-Institute, Federal Research Centre for Cultivated Plants, Institute for Breeding Research on Horticultural and Fruit Crops, 01326 Dresden, Germany (H.F.).
authors: David
authors: D
authors: Kaufholdt
authors: Institute of Pharmaceutical Biology (D.S., M.M.G., D.R., T.B., B.L., L.B.) and Institute of Plant Biology (D.K., R.H.), Technische Universität Braunschweig, 38106 Braunschweig, Germany;Plant Pathology, Institute of Integrative Biology, Eidgenössische Technische Hochschule Zürich, 8092 Zurich, Switzerland (C.C., G.A.L.B.); andJulius Kühn-Institute, Federal Research Centre for Cultivated Plants, Institute for Breeding Research on Horticultural and Fruit Crops, 01326 Dresden, Germany (H.F.).
authors: Till
authors: http://orcid.org/0000-0001-5037-6653
authors: T
authors: Beuerle
authors: Institute of Pharmaceutical Biology (D.S., M.M.G., D.R., T.B., B.L., L.B.) and Institute of Plant Biology (D.K., R.H.), Technische Universität Braunschweig, 38106 Braunschweig, Germany;Plant Pathology, Institute of Integrative Biology, Eidgenössische Technische Hochschule Zürich, 8092 Zurich, Switzerland (C.C., G.A.L.B.); andJulius Kühn-Institute, Federal Research Centre for Cultivated Plants, Institute for Breeding Research on Horticultural and Fruit Crops, 01326 Dresden, Germany (H.F.).
authors: Giovanni A L
authors: GA
authors: Broggini
authors: Institute of Pharmaceutical Biology (D.S., M.M.G., D.R., T.B., B.L., L.B.) and Institute of Plant Biology (D.K., R.H.), Technische Universität Braunschweig, 38106 Braunschweig, Germany;Plant Pathology, Institute of Integrative Biology, Eidgenössische Technische Hochschule Zürich, 8092 Zurich, Switzerland (C.C., G.A.L.B.); andJulius Kühn-Institute, Federal Research Centre for Cultivated Plants, Institute for Breeding Research on Horticultural and Fruit Crops, 01326 Dresden, Germany (H.F.).
authors: Henryk
authors: H
authors: Flachowsky
authors: Institute of Pharmaceutical Biology (D.S., M.M.G., D.R., T.B., B.L., L.B.) and Institute of Plant Biology (D.K., R.H.), Technische Universität Braunschweig, 38106 Braunschweig, Germany;Plant Pathology, Institute of Integrative Biology, Eidgenössische Technische Hochschule Zürich, 8092 Zurich, Switzerland (C.C., G.A.L.B.); andJulius Kühn-Institute, Federal Research Centre for Cultivated Plants, Institute for Breeding Research on Horticultural and Fruit Crops, 01326 Dresden, Germany (H.F.).
authors: Benye
authors: http://orcid.org/0000-0001-8527-565X
authors: B
authors: Liu
authors: Institute of Pharmaceutical Biology (D.S., M.M.G., D.R., T.B., B.L., L.B.) and Institute of Plant Biology (D.K., R.H.), Technische Universität Braunschweig, 38106 Braunschweig, Germany;Plant Pathology, Institute of Integrative Biology, Eidgenössische Technische Hochschule Zürich, 8092 Zurich, Switzerland (C.C., G.A.L.B.); andJulius Kühn-Institute, Federal Research Centre for Cultivated Plants, Institute for Breeding Research on Horticultural and Fruit Crops, 01326 Dresden, Germany (H.F.).
authors: Robert
authors: R
authors: Hänsch
authors: Institute of Pharmaceutical Biology (D.S., M.M.G., D.R., T.B., B.L., L.B.) and Institute of Plant Biology (D.K., R.H.), Technische Universität Braunschweig, 38106 Braunschweig, Germany;Plant Pathology, Institute of Integrative Biology, Eidgenössische Technische Hochschule Zürich, 8092 Zurich, Switzerland (C.C., G.A.L.B.); andJulius Kühn-Institute, Federal Research Centre for Cultivated Plants, Institute for Breeding Research on Horticultural and Fruit Crops, 01326 Dresden, Germany (H.F.) l.beerhues@tu-bs.de.
authors: Ludger
authors: http://orcid.org/0000-0002-2147-2731
authors: L
authors: Beerhues
mesh_terms: D000595:Amino Acid Sequence; D001189:Aryl Hydrocarbon Hydroxylases / Q000737:chemistry / Q000378:metabolism*; D002478:Cells, Cultured; D003001:Cloning, Molecular; D003577:Cytochrome P-450 Enzyme System / Q000737:chemistry / Q000378:metabolism*; D018076:DNA, Complementary / Q000235:genetics; D008401:Gas Chromatography-Mass Spectrometry; D018506:Gene Expression Regulation, Plant; D015723:Gene Library; D007700:Kinetics; D027845:Malus / Q000201:enzymology* / Q000235:genetics / Q000382:microbiology; D008861:Microsomes / Q000378:metabolism; D008969:Molecular Sequence Data; D010802:Phylogeny; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology; D010940:Plant Proteins / Q000737:chemistry / Q000378:metabolism*; D021381:Protein Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012717:Sesquiterpenes / Q000737:chemistry / Q000378:metabolism*; D031994:Sorbus / Q000201:enzymology* / Q000235:genetics; D013347:Subcellular Fractions / Q000201:enzymology; D013379:Substrate Specificity; D014026:Nicotiana / Q000378:metabolism; D000094162:Phytoalexins
chemical_list: D018076:DNA, Complementary; D010940:Plant Proteins; D012333:RNA, Messenger; D012717:Sesquiterpenes; C000588997:aucuparin; D003577:Cytochrome P-450 Enzyme System; D001189:Aryl Hydrocarbon Hydroxylases; C019793:biphenyl-4-hydroxylase; D000094162:Phytoalexins