@misc{PecynaUllrichBittneretal., author = {Pecyna, Marek J. and Ullrich, Ren{\´e} and Bittner, Britta and Clemens, Andr{\´e} and Scheibner, Katrin and Schubert, Roland and Hofrichter, Martin}, title = {Molecular characterization of aromatic peroxygenase from Agrocybe aegerita}, series = {Applied Microbiology and Biotechnology}, volume = {84}, journal = {Applied Microbiology and Biotechnology}, number = {5}, issn = {1432-0614}, doi = {10.1007/s00253-009-2000-1}, pages = {885 -- 897}, abstract = {Recently, a novel group of fungal peroxidases, known as the aromatic peroxygenases (APO), has been discovered. Members of these extracellular biocatalysts produced by agaric basidiomycetes such as Agrocybe aegerita or Coprinellus radians catalyze reactions—for example, the peroxygenation of naphthalene, toluene, dibenzothiophene, or pyridine—which are actually attributed to cytochrome P450 monooxygenases. Here, for the first time, genetic information is presented on this new group of peroxide-consuming enzymes. The gene of A. aegerita peroxygenase (apo1) was identified on the level of messenger RNA and genomic DNA. The gene sequence was affirmed by peptide sequences obtained through an Edman degradation and de novo peptide sequencing of the purified enzyme. Quantitative real-time reverse transcriptase polymerase chain reaction demonstrated that the course of enzyme activity correlated well with that of mRNA signals for apo1 in A. aegerita. The full-length sequences of A. aegerita peroxygenase as well as a partial sequence of C. radians peroxygenase confirmed the enzymes' affiliation to the heme-thiolate proteins. The sequences revealed no homology to classic peroxidases, cytochrome P450 enzymes, and only little homology (<30\%) to fungal chloroperoxidase produced by the ascomycete Caldariomyces fumago (and this only in the N-terminal part of the protein comprising the heme-binding region and part of the distal heme pocket). This fact reinforces the novelty of APO proteins. On the other hand, homology retrievals in genetic databases resulted in the identification of various APO homologous genes and transcripts, particularly among the agaric fungi, indicating APO's widespread occurrence in the fungal kingdom.}, 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{KlugeUllrichScheibneretal., author = {Kluge, Martin and Ullrich, Ren{\´e} and Scheibner, Katrin and Hofrichter, Martin}, title = {Formation of naphthalene hydrates in the enzymatic conversion of 1,2-dihydronaphthalene by two fungal peroxygenases and subsequent naphthalene formation}, series = {Journal of Molecular Catalysis : B, Enzymatic}, journal = {Journal of Molecular Catalysis : B, Enzymatic}, number = {103}, issn = {1381-1177}, doi = {10.1016/j.molcatb.2013.08.017}, pages = {56 -- 60}, abstract = {The formation of naphthalene hydrates (i.e. 1- and 2-hydroxy-1,2-dihydronaphthalene) displays a new activity (besides epoxidation) in the enzymatic transformation of 1,2-dihydronaphthalene by two fungal unspecific peroxygenases (UPOs) accounting for 16-19\% of the overall turnover. These arene hydrates decayed into naphthalene that in turn was converted by UPOs into naphthols. The oxygen transferred during hydroxylation was shown to derive from hydrogen peroxide proving a true peroxygenation reaction.}, language = {en} }