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dc.identifier.urihttp://hdl.handle.net/11401/77061
dc.description.sponsorshipThis work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree.en_US
dc.formatMonograph
dc.format.mediumElectronic Resourceen_US
dc.language.isoen_US
dc.publisherThe Graduate School, Stony Brook University: Stony Brook, NY.
dc.typeDissertation
dcterms.abstractMany proteins depend on a stable, well-defined three-dimensional structure to perform biological functions. Protein folding is the process through which a polypeptide chain rearranges to adopt the native structure encoded in its amino acid sequence. The high intrinsic time resolution and signal-to-noise make fluorescence spectroscopy an ideal approach for protein folding experiments. However, interpretation of intrinsic tryptophan fluorescence changes is complicated by multiple fluorescence quenching mechanisms and solvent interactions. This work describes the use of selenomethionine (M<sub>Se</sub>), the selenium analogue of methionine as a quencher of tryptophan and 4-cyanophenylalanine (F<sub>CN</sub>) fluorescence to follow protein and peptide folding. The introduction of a quencher simplifies the interpretation of fluorescence changes in both amino acids and allows for the examination of specific side chain interactions. The approach was extended to the study of protein-protein interactions by incorporation of F<sub>CN</sub> and M<sub>Se</sub> into the monomeric units of a heterodimeric coiled coil. The fluorescence signal intensity allows for the detection of coiled coil formation at lower protein concentrations than what is accessible by standard circular dichroism (CD) methods. In addition, it is shown that the fluorescence quenching system can also be used to rapidly and accurately determine the <i>K<sub>D</sub></i> of the coiled coil interaction. The structural revolution of the past several decades has generated a vast amount of data on protein structure but has had comparatively less impact on our understanding of the origins of protein stability. An analysis of published stability data was carried out examining length-dependent thermodynamic properties. A clear correlation with chain length is observed for Δ<i>H</i>, Δ<i>S</i> and Δ<i>C<sub>p</sub></i>. Although Δ<i>G°</i> at 298 K of individual proteins cannot be accurately determined using this model, predictions for the thermal stability of whole proteomes are possible. Existing datasets were significantly expanded and differences between proteins from mesophilic and thermophilic organisms were examined. The large dataset also permitted the reassessment of the existence of convergence temperatures in proteins and an analysis of thermodynamic mutation data was used to predict thermal shifts due to ligand binding.
dcterms.abstractMany proteins depend on a stable, well-defined three-dimensional structure to perform biological functions. Protein folding is the process through which a polypeptide chain rearranges to adopt the native structure encoded in its amino acid sequence. The high intrinsic time resolution and signal-to-noise make fluorescence spectroscopy an ideal approach for protein folding experiments. However, interpretation of intrinsic tryptophan fluorescence changes is complicated by multiple fluorescence quenching mechanisms and solvent interactions. This work describes the use of selenomethionine (M<sub>Se</sub>), the selenium analogue of methionine as a quencher of tryptophan and 4-cyanophenylalanine (F<sub>CN</sub>) fluorescence to follow protein and peptide folding. The introduction of a quencher simplifies the interpretation of fluorescence changes in both amino acids and allows for the examination of specific side chain interactions. The approach was extended to the study of protein-protein interactions by incorporation of F<sub>CN</sub> and M<sub>Se</sub> into the monomeric units of a heterodimeric coiled coil. The fluorescence signal intensity allows for the detection of coiled coil formation at lower protein concentrations than what is accessible by standard circular dichroism (CD) methods. In addition, it is shown that the fluorescence quenching system can also be used to rapidly and accurately determine the <i>K<sub>D</sub></i> of the coiled coil interaction. The structural revolution of the past several decades has generated a vast amount of data on protein structure but has had comparatively less impact on our understanding of the origins of protein stability. An analysis of published stability data was carried out examining length-dependent thermodynamic properties. A clear correlation with chain length is observed for Δ<i>H</i>, Δ<i>S</i> and Δ<i>C<sub>p</sub></i>. Although Δ<i>G°</i> at 298 K of individual proteins cannot be accurately determined using this model, predictions for the thermal stability of whole proteomes are possible. Existing datasets were significantly expanded and differences between proteins from mesophilic and thermophilic organisms were examined. The large dataset also permitted the reassessment of the existence of convergence temperatures in proteins and an analysis of thermodynamic mutation data was used to predict thermal shifts due to ligand binding.
dcterms.available2017-09-20T16:51:49Z
dcterms.contributorRaleigh, Daniel Pen_US
dcterms.contributorMiller, Lisa Men_US
dcterms.contributorParker, Kathlyn Aen_US
dcterms.contributorSeeliger, Markus.en_US
dcterms.creatorWatson, Matthew Douglas
dcterms.dateAccepted2017-09-20T16:51:49Z
dcterms.dateSubmitted2017-09-20T16:51:49Z
dcterms.descriptionDepartment of Chemistryen_US
dcterms.extent278 pg.en_US
dcterms.formatApplication/PDFen_US
dcterms.formatMonograph
dcterms.identifierhttp://hdl.handle.net/11401/77061
dcterms.issued2017-05-01
dcterms.languageen_US
dcterms.provenanceMade available in DSpace on 2017-09-20T16:51:49Z (GMT). No. of bitstreams: 1 Watson_grad.sunysb_0771E_13446.pdf: 6532897 bytes, checksum: fe697e24a3d6a729e5372e515178245b (MD5) Previous issue date: 1en
dcterms.publisherThe Graduate School, Stony Brook University: Stony Brook, NY.
dcterms.subjectBiophysics -- Biochemistry
dcterms.subjectfluorescence quenching, p-cyanophenylalanine, protein folding, protein stability, selenomethionine, thermal shift
dcterms.titleDevelopment of Fluorescence Probes of Protein Folding
dcterms.typeDissertation


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