title: Biotransformation of natural and synthetic isoflavonoids by two recombinant microbial enzymes.
abstract: Isolation and synthesis of isoflavonoids has become a frequent endeavor, due to their interesting biological activities. The introduction of hydroxyl groups into isoflavonoids by the use of enzymes represents an attractive alternative to conventional chemical synthesis. In this study, the capabilities of biphenyl-2,3-dioxygenase (BphA) and biphenyl-2,3-dihydrodiol 2,3-dehydrogenase (BphB) of Burkholderia sp. strain LB400 to biotransform 14 isoflavonoids synthesized in the laboratory were investigated by using recombinant Escherichia coli strains containing plasmid vectors expressing the bphA1A2A3A4 or bphA1A2A3A4B genes of strain LB400. The use of BphA and BphB allowed us to biotransform 7-hydroxy-8-methylisoflavone and 7-hydroxyisoflavone into 7,2',3'-trihydroxy-8-methylisoflavone and 7,3',4'-trihydroxyisoflavone, respectively. The compound 2'-fluoro-7-hydroxy-8-methylisoflavone was dihydroxylated by BphA at ortho-fluorinated and meta positions of ring B, with concomitant dehalogenation leading to 7,2',3',-trihydroxy-8-methylisoflavone. Daidzein (7,4'-dihydroxyisoflavone) was biotransformed by BphA, generating 7,2',4'-trihydroxyisoflavone after dehydration. Biotransformation products were analyzed by gas chromatography-mass spectrometry and nuclear magnetic resonance techniques.
authors.affiliation: Laboratorio de Microbiología Molecular y Biotecnología Ambiental, Departamento de Química, Universidad Técnica Federico Santa María, Valparaíso, Chile. michael.seeger@qui.utfsm.cl
authors.forename: Michael
authors.initials: M
authors.lastname: Seeger
authors.forename: Myriam
authors.initials: M
authors.lastname: González
authors.forename: Beatriz
authors.initials: B
authors.lastname: Cámara
authors.forename: Liliana
authors.initials: L
authors.lastname: Muñoz
authors.forename: Emilio
authors.initials: E
authors.lastname: Ponce
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Mejías
authors.forename: Carolina
authors.initials: C
authors.lastname: Mascayano
authors.forename: Yesseny
authors.initials: Y
authors.lastname: Vásquez
authors.forename: Silvia
authors.initials: S
authors.lastname: Sepúlveda-Boza
mesh_terms: D001711:Biotransformation; D019117:Burkholderia / Q000201:enzymology*; D005419:Flavonoids / Q000493:pharmacokinetics*; D007506:Iron-Sulfur Proteins; D007529:Isoflavones / Q000493:pharmacokinetics*; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D010105:Oxygenases / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism*; D013379:Substrate Specificity
chemical_list: D005419:Flavonoids; D007506:Iron-Sulfur Proteins; D007529:Isoflavones; D011994:Recombinant Proteins; D010088:Oxidoreductases; D010105:Oxygenases; C074161:biphenyl-2,3-dioxygenase; C048338:trans-1,2-dihydrobenzene-1,2-diol dehydrogenase