TY - BOOK A1 - Zellhöfer, David A1 - Weber-Wulff, Debora A1 - Class, Christa A1 - Coy, Wolfgang A1 - Kurz, Constanze A1 - Ullrich, Sebastian T1 - Fallstudien zur Ethik in Wissenschaft, Wirtschaft, Technik und Gesellschaft Y1 - 2011 SN - 978-3-86644-608-3 PB - KIT Scientific Publishing CY - Karlsruhe ER - TY - GEN A1 - Zellhöfer, David A1 - Ullrich, Sebastian T1 - Gewissensbits- Wie würden Sie urteilen? Fallbeispiel: Maschinelle Hausarbeiten T2 - Informatik Spektrum Y1 - 2011 SN - 0170-6012 VL - 34 IS - 1 SP - 107 EP - 108 ER - TY - CHAP A1 - Vasileiadou, Eleni Magdalini A1 - Mißler-Behr, Magdalena A1 - Ullrich, Sebastian T1 - Relational Capital Management of new Ventures Through Virtual Embeddedness and Social Media Y1 - 2011 ER - TY - BOOK A1 - Vasileiadou, Eleni Magdalini A1 - Ullrich, Sebastian A1 - Tamm, Gerrit T1 - Cloud Computing Definitions and Approaches - Levels of Abstraction: IAAS, PAAS, SAAS Y1 - 2011 PB - Asperado GmbH & SRH Hochschule Berlin ER - TY - GEN A1 - Peter, Sebastian A1 - Karich, Alexander A1 - Ullrich, René A1 - Gröbe, Glenn A1 - Scheibner, Katrin A1 - Hofrichter, Martin T1 - Enzymatic one-pot conversion of cyclohexane into cyclohexanone: Comparison of four fungal peroxygenases T2 - Journal of Molecular Catalysis : B, Enzymatic N2 - Unspecific peroxygenases (UPO; EC 1.11.2.1) represent a group of secreted heme-thiolate proteins that are capable of catalyzing the mono-oxygenation of diverse organic compounds, using only H2O2 as a co-substrate. Here we show that the four peroxygenases AaeUPO, MroUPO, rCciUPO and rNOVO catalyze the stepwise hydroxylation of cyclohexane to cyclohexanol and cyclohexanone. The catalytic efficiencies (kcat/Km) for the initial hydroxylation were in the same order of magnitude for all four peroxygenases (∼104 M−1 s−1), whereas they differed in the second step. The conversion of cyclohexanol by AaeUPO and rCciUPO was 1–2 orders of magnitude less efficient (∼102 M−1 s−1) than by MroUPO and rNOVO (∼104 M−1 s−1). The highest conversion rate in terms of H2O2 utilization was accomplished by MroUPO under repeated addition of the peroxide (87% in relation to the total products formed). Using the latter UPO, we successfully established a micro-mixing reaction device (SIMM-V2) for the oxidation of cyclohexane. As cyclohexanone is a chemical of high relevance, for example, as starting material for polymer syntheses or as organic solvent, new enzymatic production pathways for this compound are of interest to complement existing chemical and biotechnological approaches. Stable and versatile peroxygenases, as those presented here, may form a promising biocatalytic platform for the development of such enzyme-based processes. KW - cyclohexane KW - cyclohexanol KW - cyclohexanone KW - UPO KW - Peroxygenase Y1 - 2014 UR - http://www.sciencedirect.com/science/article/pii/S138111771300266X U6 - https://doi.org/10.1016/j.molcatb.2013.09.016 IS - 103 SP - 47 EP - 51 ER - TY - GEN A1 - Poraj-Kobielska, Marzena A1 - Peter, Sebastian A1 - Leonhardt, Sabrina A1 - Ullrich, René A1 - Scheibner, Katrin A1 - Hofrichter, Martin T1 - Immobilization of unspecific peroxygenases (EC 1.11.2.1) in PVA/PEG gel and hollow fiber modules T2 - Biochemical Engineering Journal N2 - The immobilization of enzymes has many advantages, such as higher stability, easier handling, and reuse of the catalyst. Here we report, for the first time, two effective methods for the immobilization of unspecific peroxygenase (UPO; EC 1.11.2.1). This biocatalyst type comprises heavily glycosylated heme-thiolate proteins that catalyze various biotechnologically relevant oxyfunctionalizations. Both the encapsulation in cryogel and the retention of the enzyme in hollow fiber modules were found to be efficient methods for their immobilization. After encapsulation, the enzyme still exhibited 60% of its initial activity. Interestingly, we did not find differences in the kinetic parameters of free and immobilized UPOs. In long-term experiments, the conversion of the pharmaceutical diclofenac with immobilized UPOs in different reactor types yielded between 62 mg and 154 mg of the major human drug metabolite 4′-hydroxydiclofenac. The maximal total turnover number was about 60-fold higher compared to the free enzyme. A test over 5 months showed that storage of encapsulated UPOs in non-polar solvents (e.g., cyclohexane) helps to preserve the enzyme stability and increases their relative activity (by about ∼150%, in the case of diclofenac hydroxylation). In addition to the hydrophilic substrate diclofenac, encapsulated UPOs also oxidized the hydrophobic model compound cyclohexane. KW - Peroxygenase Y1 - 2015 UR - http://www.sciencedirect.com/science/article/pii/S1369703X15000820 U6 - https://doi.org/10.1016/j.bej.2015.02.037 SN - 1369-703X VL - 98 SP - 144 EP - 150 ER -