@misc{PorajKobielskaKinneUllrichetal., author = {Poraj-Kobielska, Marzena and Kinne, Matthias and Ullrich, Ren{\´e} and Scheibner, Katrin and Kayser, Gernot and Hammel, Kenneth E. and Hofrichter, Martin}, title = {Preparation of human drug metabolites using fungal peroxygenases}, series = {Biochemical Pharmacology}, volume = {82}, journal = {Biochemical Pharmacology}, number = {7}, issn = {1873-2968}, doi = {10.1016/j.bcp.2011.06.020}, pages = {789 -- 796}, abstract = {The synthesis of hydroxylated and O- or N-dealkylated human drug metabolites (HDMs) via selective monooxygenation remains a challenging task for synthetic organic chemists. Here we report that aromatic peroxygenases (APOs; EC 1.11.2.1) secreted by the agaric fungi Agrocybe aegerita and Coprinellus radians catalyzed the H₂O₂-dependent selective monooxygenation of diverse drugs, including acetanilide, dextrorphan, ibuprofen, naproxen, phenacetin, sildenafil and tolbutamide. Reactions included the hydroxylation of aromatic rings and aliphatic side chains, as well as O- and N-dealkylations and exhibited different regioselectivities depending on the particular APO used. At best, desired HDMs were obtained in yields greater than 80\% and with isomeric purities up to 99\%. Oxidations of tolbutamide, acetanilide and carbamazepine in the presence of H₂¹⁸O₂ resulted in almost complete incorporation of ¹⁸O into the corresponding products, thus establishing that these reactions are peroxygenations. The deethylation of phenacetin-d₁ showed an observed intramolecular deuterium isotope effect [(k(H)/k(D))(obs)] of 3.1±0.2, which is consistent with the existence of a cytochrome P450-like intermediate in the reaction cycle of APOs. Our results indicate that fungal peroxygenases may be useful biocatalytic tools to prepare pharmacologically relevant drug metabolites.}, language = {en} } @misc{KinnePorajKobielskaArandaetal., author = {Kinne, Matthias and Poraj-Kobielska, Marzena and Aranda, Elisabet and Ullrich, Ren{\´e} and Hammel, Kenneth E. and Scheibner, Katrin and Hofrichter, Martin}, title = {Regioselective preparation of 5-hydroxypropranolol and 4′-hydroxydiclofenac with a fungal peroxygenase}, series = {Bioorganic \& Medicinal Chemistry Letters}, volume = {19}, journal = {Bioorganic \& Medicinal Chemistry Letters}, number = {11}, issn = {1464-3405}, doi = {10.1016/j.bmcl.2009.04.015}, pages = {3085 -- 3087}, abstract = {An extracellular peroxygenase of Agrocybe aegerita catalyzed the H2O2-dependent hydroxylation of the multi-function beta-adrenergic blocker propranolol (1-naphthalen-1-yloxy-3-(propan-2-ylamino)propan-2-ol) and the non-steroidal anti-inflammatory drug diclofenac (2-[2-[(2,6-dichlorophenyl)amino]phenyl]acetic acid) to give the human drug metabolites 5-hydroxypropranolol (5-OHP) and 4′-hydroxydiclofenac (4′-OHD). The reactions proceeded regioselectively with high isomeric purity and gave the desired 5-OHP and 4′-OHD in yields up to 20\% and 65\%, respectively. 18O-labeling experiments showed that the phenolic hydroxyl groups in 5-OHP and 4′-OHD originated from H2O2, which establishes that the reaction is mechanistically a peroxygenation. Our results raise the possibility that fungal peroxygenases may be useful for versatile, cost-effective, and scalable syntheses of drug metabolites.}, language = {en} } @misc{KlugeUllrichDolgeetal., author = {Kluge, Martin and Ullrich, Ren{\´e} and Dolge, Christoph and Scheibner, Katrin and Hofrichter, Martin}, title = {Hydroxylation of naphthalene by aromatic peroxygenase from Agrocybe aegerita proceeds via oxygen transfer from H2O2 and intermediary epoxidation}, series = {Applied Microbiology and Biotechnology}, volume = {81}, journal = {Applied Microbiology and Biotechnology}, number = {6}, issn = {0175-7598}, doi = {10.1007/s00253-008-1704-y}, pages = {1071 -- 1076}, abstract = {Agrocybe aegerita peroxidase/peroxygenase (AaP) is an extracellular fungal biocatalyst that selectively hydroxylates the aromatic ring of naphthalene. Under alkaline conditions, the reaction proceeds via the formation of an intermediary product with a molecular mass of 144 and a characteristic UV absorption spectrum (A max 210, 267, and 303 nm). The compound was semistable at pH 9 but spontaneously hydrolyzed under acidic conditions (pH <7) into 1-naphthol as major product and traces of 2-naphthol. Based on these findings and literature data, we propose naphthalene 1,2-oxide as the primary product of AaP-catalyzed oxygenation of naphthalene. Using 18O-labeled hydrogen peroxide, the origin of the oxygen atom transferred to naphthalene was proved to be the peroxide that acts both as oxidant (primary electron acceptor) and oxygen source.}, language = {en} } @misc{KinneUllrichHammeletal., author = {Kinne, Matthias and Ullrich, Ren{\´e} and Hammel, Kenneth E. and Scheibner, Katrin and Hofrichter, Martin}, title = {Regioselective preparation of (R)-2-(4-Hydroxyphenoxy)propionic acid with a fungal peroxygenase}, series = {Tetrahedron Letters}, volume = {49}, journal = {Tetrahedron Letters}, number = {41}, issn = {1873-3581}, doi = {10.1016/j.tetlet.2008.07.152}, pages = {5950 -- 5953}, abstract = {The extracellular heme-thiolate peroxygenase of Agrocybe aegerita catalyzed the H2O2-dependent hydroxylation of 2-phenoxypropionic acid (POPA) to give the herbicide precursor 2-(4-hydroxyphenoxy)propionic acid (HPOPA). The reaction proceeded regioselectively with an isomeric purity near 98\%, and yielded the desired R-isomer of HPOPA with an enantiomeric excess of 60\%. 18O-labeling experiments showed that the phenolic hydroxyl in HPOPA originated from H2O2, which establishes that the reaction is mechanistically a peroxygenation. Our results raise the possibility that fungal peroxygenases may be useful for a variety of organic oxidations.}, language = {en} } @misc{KlugeUllrichScheibneretal., author = {Kluge, Martin and Ullrich, Ren{\´e} and Scheibner, Katrin and Hofrichter, Martin}, title = {Spectrophotometric assay for detection of aromatic hydroxylation catalyzed by fungal haloperoxidase-peroxygenase}, series = {Applied Microbiology and Biotechnology}, volume = {75}, journal = {Applied Microbiology and Biotechnology}, number = {6}, issn = {1432-0614}, doi = {10.1007/s00253-007-0942-8}, pages = {1473 -- 1478}, abstract = {Agrocybe aegerita peroxidase (AaP) is a versatile heme-thiolate protein that can act as a peroxygenase and catalyzes, among other reactions, the hydroxylation of aromatic rings. This paper reports a rapid and selective spectrophotometric method for directly detecting aromatic hydroxylation by AaP. The weakly activated aromatic compound naphthalene served as the substrate that was regioselectively converted into 1-naphthol in the presence of the co-substrate hydrogen peroxide. Formation of 1-naphthol was followed at 303 nm (ɛ 303 = 2,010 M-1 cm-1), and the apparent Michaelis-Menten (K m) and catalytic (k cat) constants for the reaction were estimated to be 320 μM and 166 s-1, respectively. This method will be useful in screening of fungi and other microorganisms for extracellular peroxygenase activities and in comparing and assessing different catalytic activities of haloperoxidase-peroxygenases.}, language = {en} }