43 research outputs found
Photobiocatalytic chemistry of oxidoreductases using water as the electron donor
[EN] To date, water has been poorly studied as the sacrificial electron donor for biocatalytic redox reactions using isolated enzymes. Here we demonstrate that water can also be turned into a sacrificial electron donor to promote biocatalytic redox reactions. The thermodynamic driving force required for water oxidation is obtained from UV and visible light by means of simple titanium dioxide-based photocatalysts. The electrons liberated in this process are delivered to an oxidoreductase by simple flavin redox mediators. Overall, the feasibility of photobiocatalytic, water-driven bioredox reactions is demonstrated.Financial support from the Spanish Science and Innovation Ministry (Consolider Ingenio 2010-MULTICAT CSD 2009-00050, Subprograma de apoyo a Centros y Universidades de Excelencia Severo Ochoa SEV 2012 0267). M. M. acknowledges the Spanish Science and Innovation Ministry for a 'Juan de la Cierva' postdoctoral contract. S. G. acknowledges the European Union Marie Curie Programme (ITN 'Biotrains', Grant Agreement No. 238531).Mifsud Grau, M.; Gargiulo, S.; Iborra Chornet, S.; Arends, IWCE.; Hollmann, F.; Corma CanĂłs, A. (2014). Photobiocatalytic chemistry of oxidoreductases using water as the electron donor. Nature Communications. 5:1-6. https://doi.org/10.1038/ncomms4145S165Bornscheuer, U. T. et al. Engineering the third wave of biocatalysis. Nature 485, 185–194 (2012).Breuer, M. et al. Industrial methods for the production of optically active intermediates. Angew. Chem. Int. Ed. 43, 788–824 (2004).Pollard, D. J. & Woodley, J. M. Biocatalysis for pharmaceutical intermediates: the future is now. Trends Biotechnol. 25, 66–73 (2007).Ran, N., Zhao, L., Chen, Z. & Tao, J. Recent applications of biocatalysis in developing green chemistry for chemical synthesis at the industrial scale. Green. Chem. 10, 361–372 (2008).Schmid, A. et al. Industrial biocatalysis today and tomorrow. Nature 409, 258–268 (2001).Schmid, A., Hollmann, F., Park, J. B. & BĂĽhler, B. The use of enzymes in the chemical industry in Europe. Curr. Opin. Biotechnol. 13, 359–366 (2002).Schoemaker, H. E., Mink, D. & Wubbolts, M. G. Dispelling the myths-biocatalysis in industrial synthesis. Science 299, 1694–1697 (2003).Turner, N. J. & O’Reilly, E. Biocatalytic retrosynthesis. Nat. Chem. Biol. 9, 285–288 (2013).Drauz K., Gröger H., May O. (eds)Enzyme Catalysis in Organic Synthesis Wiley-VCH: Weinheim, (2012).Weckbecker, A., Gröger, H. & Hummel, W. Regeneration of nicotinamide coenzymes: principles and applications for the synthesis of chiral compounds. inBiosystems Engineering I: Creating Superior Biocatalysts pp195–242Springer: Berlin, (2010).Van der Donk, W. A. & Zhao, H. Recent developments in pyridine nucleotide regeneration. Curr. Opin. Biotechnol. 14, 421–426 (2003).Wu, H. et al. Methods for the regeneration of nicotinamide coenzymes. Green. Chem. 15, 1773–1789 (2013).Rodriguez, C., Lavandera, I. & Gotor, V. Recent advances in cofactor regeneration systems applied to biocatalyzed oxidative processes. Curr. Org. Chem. 16, 2525–2541 (2012).Reipa, V., Mayhew, M. P. & Vilker, V. L. A direct electrode-driven P450 cycle for biocatalysis. Proc. Natl Acad. Sci. USA 94, 13554–13558 (1997).Bernard, J., van Heerden, E., Arends, I. W. C. E., Opperman, D. J. & Hollmann, F. Chemoenzymatic reduction of conjugated C=C double bonds. Chem. Cat. Chem. 4, 196–199 (2012).Hollmann, F., Arends, I. W. C. E. & BĂĽhler, K. Biocatalytic redox reactions for organic synthesis: nonconventional regeneration methods. Chem. Cat. Chem. 2, 762–782 (2010).Hollmann, F., Hofstetter, K., Habicher, T., Hauer, B. & Schmid, A. Direct electrochemical regeneration of monooxygenase subunits for biocatalytic asymmetric epoxidation. J. Am. Chem. Soc. 127, 6540–6541 (2005).Hollmann, F., Lin, P.-C., Witholt, B. & Schmid, A. Stereospecific biocatalytic epoxidation: the first example of direct regeneration of a fad-dependent monooxygenase for catalysis. J. Am. Chem. Soc. 125, 8209–8217 (2003).Hollmann, F. & Schmid, A. Towards [Cp*Rh(bpy)(H2O)]2+-promoted P450 catalysis: direct regeneration of CytC. J. Inorg. Biochem. 103, 313–315 (2009).Hollmann, F., Taglieber, A., Schulz, F. & Reetz, M. T. A light-driven stereoselective biocatalytic oxidation. Angew. Chem. Int. Ed. 46, 2903–2906 (2007).Mifsud Grau, M. et al. Photoenzymatic reduction of C=C double bonds. Adv. Synth. Catal. 351, 3279–3286 (2009).Ruinatscha, R., Dusny, C., Buehler, K. & Schmid, A. Productive asymmetric styrene epoxidation based on a next generation electroenzymatic methodology. Adv. Synth. Catal. 351, 2505–2515 (2009).Schwaneberg, U., Appel, D., Schmitt, J. & Schmid, R. D. P450 in biotechnology: zinc driven ω-hydroxylation of p-nitrophenoxydodecanoic acid using P450 BM-3 F87A as a catalyst. J. Biotechnol. 84, 249–257 (2000).Taglieber, A., Schulz, F., Hollmann, F., Rusek, M. & Reetz, M. T. Light-Driven Biocatalytic Oxidation and Reduction Reactions: Scope and Limitations. Chem. Bio. Chem. 9, 565–572 (2008).Udit, A. K., Arnold, F. H. & Gray, H. B. Cobaltocene-mediated catalytic monooxygenation using holo and heme domain cytochrome P450 BM3. J. Inorg. Biochem. 98, 1547–1550 (2004).Udit, A. K., Hill, M. G., Bittner, V. G., Arnold, F. H. & Gray, H. B. Reduction of dioxygen catalyzed by pyrene-wired heme domain cytochrome p450 bm3 electrodes. J. Am. Chem. Soc. 126, 10218–10219 (2004).Unversucht, S., Hollmann, F., Schmid, A. & van PĂ©e, K.-H. FADH2-Dependence of Tryptophan 7-Halogenase. Adv. Synth. Catal. 347, 1163–1167 (2005).Zilly, F. E., Taglieber, A., Schulz, F., Hollmann, F. & Reetz, M. T. Deazaflavins as mediators in light-driven cytochrome P450 catalyzed hydroxylations. Chem. Commun. 7152–7154 (2009).Yehezkeli, O. et al. Integrated photosystem II-based photo-bioelectrochemical cells. Nat. Commun. 3, 742 (2012).Duan, L. et al. A molecular ruthenium catalyst with water-oxidation activity comparable to that of photosystem II. Nat. Chem. 4, 418–423 (2012).Dau, H., Zaharieva, I. & Haumann, M. Recent developments in research on water oxidation by photosystem II. Curr. Opin. Chem. Biol. 16, 3–10 (2012).Qu, Y. & Duan, X. Progress, challenge and perspective of heterogeneous photocatalysts. Chem. Soc. Rev. 42, 2568–2580 (2013).Takanabe, K. & Domen, K. Preparation of inorganic photocatalytic materials for overall water splitting. Chem. Cat. Chem. 4, 1485–1497 (2012).Wee, T.-L. et al. Photochemical synthesis of a water oxidation catalyst based on cobalt nanostructures. J. Am. Chem. Soc. 133, 16742–16745 (2011).Cargnello, M. & Fornasiero, P. Photocatalysis by nanostructured TiO2 based semiconductors. inHandbook of Green Chemistry, Green Nanoscience (eds Selva M., Perosa A. Wiley-VCH: Weinheim, (2010).Liu, S. Q. & Chen, A. C. Coadsorption of horseradish peroxidase with thionine on TiO2: Nanotubes for biosensing. Langmuir 21, 8409–8413 (2005).Zhang, Y., He, P. L. & Hu, N. F. Horseradish peroxidase immobilized in TiO2 nanoparticle films on pyrolytic graphite electrodes: direct electrochemistry and bioelectrocatalysis. Electrochim. Acta 49, 1981–1988 (2004).Chen, D., Zhang, H., Li, X. & Li, J. H. Biofunctional titania nanotubes for visible-light-activated photoelectrochemical biosensing. Anal. Chem. 82, 2253–2261 (2010).Gomes Silva, C. U., Juárez, R., Marino, T., Molinari, R. & GarcĂa, H. Influence of excitation wavelength (UV or visible light) on the photocatalytic activity of titania containing gold nanoparticles for the generation of hydrogen or oxygen from water. J. Am. Chem. Soc. 133, 595–602 (2010).Opperman, D. J., Piater, L. A. & van Heerden, E. A novel chromate reductase from Thermus scotoductus SA-01 related to old yellow enzyme. J. Bacteriol. 190, 3076–3082 (2008).Opperman, D. J. et al. Crystal structure of a thermostable old yellow enzyme from Thermus scotoductus SA-01. Biochem. Biophys. Res. Commun. 393, 426–431 (2010).Choi, S. H. et al. The influence of non-stoichiometric species of V/TiO2 catalysts on selective catalytic reduction at low temperature. J. Mol. Catal. A: Chem. 304, 166–173 (2009)
Use of a gonadotropin releasing hormone agonist implant as an alternative for surgical castration in male ferrets (Mustela putorius furo)
Surgical castration in ferrets has been implicated as an etiological factor in the development of hyperadrenocorticism in this species due to a castration-related increase in plasma gonadotropins. In search for a suitable alternative, the effect of treatment with the depot GnRH-agonist implant, deslorelin, on plasma testosterone concentrations and concurrent testes size, spermatogenesis, and the typical musky odor of intact male ferrets was investigated. Twenty-one male ferrets, equally divided into three groups, were either surgically castrated, received a slow release deslorelin implant or received a placebo implant. Plasma FSH and testosterone concentrations, testis size and spermatogenesis were all suppressed after the use of the deslorelin implant. The musky odor in the ferrets which had received a deslorelin implant was less compared to the ferrets which were either surgically castrated or had received a placebo implant. These results indicate that the deslorelin implant effectively prevents reproduction and the musky odor of intact male ferrets and is therefore considered a suitable alternative for surgical castration in these animals. (C) 2008 Elsevier Inc. All rights reserved
The composition and initial evaluation of a grimace scale in ferrets after surgical implantation of a telemetry probe
An outbreak of thyroid hyperplasia (goiter) with high mortality in budgerigars ( Melopsittacus undulatus
Collaborative and Spiritual Inquiry: Positive Leadership in Organizational Change and Higher Education
I'll never forgive you: High conflict divorce, social network, and co-parenting conflicts
Contains fulltext :
177372.pdf (Publisher’s version ) (Open Access)The relation between divorce, co-parenting conflicts, and children's adjustment problems has been well established. An unresolved question for research and clinical interventions, however, is how conflicts between parents are maintained and/or escalate. This cross-sectional research tested the hypothesis that co-parenting conflicts in divorced couples are associated with perceived social network disapproval and that this relation is mediated by parents' tendency to forgive each other. In Study 1, a convenience sample of 136 divorced parents recruited via online forums, we showed that perceived social network disapproval was indeed positively related to co-parenting conflicts and that parents'tendency to forgive the other parent - albeit partly - explained this relationship. Strength of 0our research is that in Study 2, 110 parents referred to children's mental health care because the wellbeing of the children was severely compromised by the severity of the conflicts between parents, we replicated these results. In both studies perceived social network disapproval and co-parenting conflicts were positively related and this link was mediated by forgiveness: perceived social network disapproval was negatively related to forgiveness, which in turn was negatively related to more parental conflicts.12 p