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dc.contributor.advisorKamer, Paul (Paul C. J.)
dc.contributor.authorObrecht, Lorenz
dc.coverage.spatialx, 183 p.en_US
dc.date.accessioned2015-08-17T09:07:24Z
dc.date.available2015-08-17T09:07:24Z
dc.date.issued2015
dc.identifier.urihttps://hdl.handle.net/10023/7248
dc.description.abstractThis thesis describes the synthesis, characterisation and application of artificial metalloenzymes as catalysts. The focus was on two mutants of SCP-2L (SCP-2L A100C and SCP-2L V83C) both of which possess a hydrophobic tunnel in which apolar substrates can accumulate. The crystal structure of SCP-2L A100C was determined and discussed with a special emphasis on its hydrophobic tunnel. The SCP-2L mutants were covalently modified at their unique cysteine with two different N-ligands (phenanthroline or dipicolylamine based) or three different phosphine ligands (all based on triphenylphosphine) in order to increase their binding capabilities towards metals. The metal binding capabilities of these artificial proteins towards different transition metals was determined. Phenanthroline modified SCP-2L was found to be a promising scaffold for Pd(II)-, Cu(II)-, Ni(II)- and Co(II)-enzymes while dipicolylamine-modified SCP-2L was found to be a promising scaffold for Pd(II)-enzymes. The rhodium binding capacity of two additional phosphine modified protein scaffolds was also investigated. Promising scaffolds for Rh(I)- and Ir(I)-enzymes were identified. Rh-enzymes of the phosphine modified proteins were tested in the aqueous-organic biphasic hydroformylation of linear long chain 1-alkenes and compared to the Rh/TPPTS reference system. Some Rh-enzymes were found to be several orders of magnitude more active than the model system while yielding comparable selectivities. The reason for this remarkable reactivity increase could not be fully elucidated but several potential modes of action could be excluded. Cu-, Co-, and Ni-enzymes of N-ligand modified SCP-2L A100C were tested in the asymmetric Diels-Alder reaction between cyclopentadiene and trans-azachalcone. A promising 29% ee for the exo-product was found for the phenanthroline modified protein in the presence of nickel. Further improvement of these catalyst systems by chemical means (e.g. optimisation of ligand structure) and bio-molecular tools (e.g. optimisation of protein environment) can lead to even more active and (enantio)selective catalysts in the future.en_US
dc.language.isoenen_US
dc.publisherUniversity of St Andrews
dc.subjectArtificial metalloenzymesen_US
dc.subjectArtificial enzymesen_US
dc.subjectCatalysisen_US
dc.subjectEnantioselectiveen_US
dc.subjectHydroformylationen_US
dc.subjectDiels-Alderen_US
dc.subjectRh-enzymeen_US
dc.subjectNi-enzymeen_US
dc.subjectPd-enzymeen_US
dc.subjectPt-enzymeen_US
dc.subjectZn-enzymeen_US
dc.subjectMn-enzymeen_US
dc.subjectFe-enzymeen_US
dc.subjectCu-enzymeen_US
dc.subjectCo-enzymeen_US
dc.subjectRu-enzymeen_US
dc.subjectRe-enzymeen_US
dc.subjectIr-enzymeen_US
dc.subjectAqueous-organic biphasic hydroformylationen_US
dc.subjectHydroformylation of long chain 1-alkeneen_US
dc.subjectPhosphine bearing enzymesen_US
dc.subjectNitrogen-ligand bearing enzymesen_US
dc.subject.lccQP601.7O3
dc.subject.lcshMetalloenzymesen_US
dc.subject.lcshCatalysisen_US
dc.subject.lcshEnantioselective catalystsen_US
dc.subject.lcshHydroformylationen_US
dc.titleArtificial metalloenzymes in catalysisen_US
dc.typeThesisen_US
dc.type.qualificationlevelDoctoralen_US
dc.type.qualificationnamePhD Doctor of Philosophyen_US
dc.publisher.institutionThe University of St Andrewsen_US


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