{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/21183"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/21183","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Semisynthetic cytochrome c site-67 substitutions","abstract":"Highly conserved tyrosine-67 of mitochondrial cytochrome $c$ is thought to be involved in important hydrogen bonding interactions in the hydrophobic heme pocket of the protein. In order to investigate the hydrogen bonding role of this residue, two site-67 analogs were prepared by semisynthetic methods: (Hse-65, Phe-67)cytochrome $c$ and (Hse-65, p-F-Phe-67)cytochrome $c$. The analog proteins were reconstituted from a native heme-containing peptide, residues 1 to 65, prepared by CNBr degradation of horse heart cytochrome $c$, and a synthetic peptide, residues 66-104, prepared by solid-phase peptide synthesis. The analogs were characterized and compared to (Hse-65)cytochrome $c$ and the native protein. Both analogs have well developed 695-nm visible absorption bands and are active in a cytochrome $c$ oxidase assay. The redox potentials of (Hse-65, p-F-Phe-67)cytochrome $c$ and (Hse-65, Phe-67)cytochrome $c$ were lower than the native protein by 45 and 50 mV respectively. Both analogs had similar binding constants for imidazole, increased approximately 10-fold over the native protein and (Hse-65)cytochrome $c$. In a cyanide binding study, however, (Hse-65, p-F-Phe-67)cytochrome $c$ had a 3- to 5-fold lower binding constant than the other proteins. The pK$\\sb{\\rm a}$ values for the alkaline transition for (Hse-65, p-F-Phe-67)cytochrome $c$ was 9.7, and for (Hse-65, Phe-67)cytochrome $c$ was $\\geq$10.3, compared to 9.4 for the native protein. The redox potential result may be explained on the basis of a more open heme pocket in the two site-67 analog proteins. Results from ligand binding and alkaline transition studies may be explained best as stabilization or destabilization of the forms of the analogs in which the Met-80 to heme iron bond has been displaced with another ligand, rather than as stabilization of the forms in which the Met-80 to heme iron bond is intact.","abstract_html":"Highly conserved tyrosine-67 of mitochondrial cytochrome $c$ is thought to be involved in important hydrogen bonding interactions in the hydrophobic heme pocket of the protein. In order to investigate the hydrogen bonding role of this residue, two site-67 analogs were prepared by semisynthetic methods: (Hse-65, Phe-67)cytochrome $c$ and (Hse-65, p-F-Phe-67)cytochrome $c$. The analog proteins were reconstituted from a native heme-containing peptide, residues 1 to 65, prepared by CNBr degradation of horse heart cytochrome $c$, and a synthetic peptide, residues 66-104, prepared by solid-phase peptide synthesis. The analogs were characterized and compared to (Hse-65)cytochrome $c$ and the native protein. Both analogs have well developed 695-nm visible absorption bands and are active in a cytochrome $c$ oxidase assay. The redox potentials of (Hse-65, p-F-Phe-67)cytochrome $c$ and (Hse-65, Phe-67)cytochrome $c$ were lower than the native protein by 45 and 50 mV respectively. Both analogs had similar binding constants for imidazole, increased approximately 10-fold over the native protein and (Hse-65)cytochrome $c$. In a cyanide binding study, however, (Hse-65, p-F-Phe-67)cytochrome $c$ had a 3- to 5-fold lower binding constant than the other proteins. The pK$\\sb{\\rm a}$ values for the alkaline transition for (Hse-65, p-F-Phe-67)cytochrome $c$ was 9.7, and for (Hse-65, Phe-67)cytochrome $c$ was $\\geq$10.3, compared to 9.4 for the native protein. The redox potential result may be explained on the basis of a more open heme pocket in the two site-67 analog proteins. Results from ligand binding and alkaline transition studies may be explained best as stabilization or destabilization of the forms of the analogs in which the Met-80 to heme iron bond has been displaced with another ligand, rather than as stabilization of the forms in which the Met-80 to heme iron bond is intact.","abstract_has_math":true,"creators":["Frauenhoff, Mary Mills"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Chemistry","degree_department":null,"school":null,"contributors":["Kenneth S. Suslick"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T13:00:53Z","date_published":"2011-05-07T13:00:53Z","updated_at":"2026-07-22T22:25:17Z","subjects":["Chemistry, Biochemistry","Chemistry, Inorganic"],"languages":["eng"],"rights":["Copyright 1990 Frauenhoff, Mary Mills"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9026184","(UMI)AAI9026184"],"render_values":[{"text":"AAI9026184","href":null,"code":true},{"text":"(UMI)AAI9026184","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/21183","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Kenneth S. 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In order to investigate the hydrogen bonding role of this residue, two site-67 analogs were prepared by semisynthetic methods: (Hse-65, Phe-67)cytochrome $c$ and (Hse-65, p-F-Phe-67)cytochrome $c$. The analog proteins were reconstituted from a native heme-containing peptide, residues 1 to 65, prepared by CNBr degradation of horse heart cytochrome $c$, and a synthetic peptide, residues 66-104, prepared by solid-phase peptide synthesis. The analogs were characterized and compared to (Hse-65)cytochrome $c$ and the native protein. Both analogs have well developed 695-nm visible absorption bands and are active in a cytochrome $c$ oxidase assay. The redox potentials of (Hse-65, p-F-Phe-67)cytochrome $c$ and (Hse-65, Phe-67)cytochrome $c$ were lower than the native protein by 45 and 50 mV respectively. Both analogs had similar binding constants for imidazole, increased approximately 10-fold over the native protein and (Hse-65)cytochrome $c$. In a cyanide binding study, however, (Hse-65, p-F-Phe-67)cytochrome $c$ had a 3- to 5-fold lower binding constant than the other proteins. The pK$\\sb{\\rm a}$ values for the alkaline transition for (Hse-65, p-F-Phe-67)cytochrome $c$ was 9.7, and for (Hse-65, Phe-67)cytochrome $c$ was $\\geq$10.3, compared to 9.4 for the native protein. The redox potential result may be explained on the basis of a more open heme pocket in the two site-67 analog proteins. Results from ligand binding and alkaline transition studies may be explained best as stabilization or destabilization of the forms of the analogs in which the Met-80 to heme iron bond has been displaced with another ligand, rather than as stabilization of the forms in which the Met-80 to heme iron bond is intact.","Made available in DSpace on 2011-05-07T13:00:53Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9026184.pdf: 6628344 bytes, checksum: 517e6c421bc54279dc3df340f402cbf5 (MD5) Previous issue date: 1990","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:49:02Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:22:16-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission","U of I Only"]},{"key":"dc:title","label":"Title","values":["Semisynthetic cytochrome c site-67 substitutions"]}]}],"canonical_facts":{"dc:contributor":["Kenneth S. Suslick"],"dc:creator":["Frauenhoff, Mary Mills"],"dc:date":["2011-05-07T13:00:53Z","10000-01-01","1990"],"dc:description":["Highly conserved tyrosine-67 of mitochondrial cytochrome $c$ is thought to be involved in important hydrogen bonding interactions in the hydrophobic heme pocket of the protein. In order to investigate the hydrogen bonding role of this residue, two site-67 analogs were prepared by semisynthetic methods: (Hse-65, Phe-67)cytochrome $c$ and (Hse-65, p-F-Phe-67)cytochrome $c$. The analog proteins were reconstituted from a native heme-containing peptide, residues 1 to 65, prepared by CNBr degradation of horse heart cytochrome $c$, and a synthetic peptide, residues 66-104, prepared by solid-phase peptide synthesis. The analogs were characterized and compared to (Hse-65)cytochrome $c$ and the native protein. Both analogs have well developed 695-nm visible absorption bands and are active in a cytochrome $c$ oxidase assay. The redox potentials of (Hse-65, p-F-Phe-67)cytochrome $c$ and (Hse-65, Phe-67)cytochrome $c$ were lower than the native protein by 45 and 50 mV respectively. Both analogs had similar binding constants for imidazole, increased approximately 10-fold over the native protein and (Hse-65)cytochrome $c$. In a cyanide binding study, however, (Hse-65, p-F-Phe-67)cytochrome $c$ had a 3- to 5-fold lower binding constant than the other proteins. The pK$\\sb{\\rm a}$ values for the alkaline transition for (Hse-65, p-F-Phe-67)cytochrome $c$ was 9.7, and for (Hse-65, Phe-67)cytochrome $c$ was $\\geq$10.3, compared to 9.4 for the native protein. The redox potential result may be explained on the basis of a more open heme pocket in the two site-67 analog proteins. Results from ligand binding and alkaline transition studies may be explained best as stabilization or destabilization of the forms of the analogs in which the Met-80 to heme iron bond has been displaced with another ligand, rather than as stabilization of the forms in which the Met-80 to heme iron bond is intact.","Made available in DSpace on 2011-05-07T13:00:53Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9026184.pdf: 6628344 bytes, checksum: 517e6c421bc54279dc3df340f402cbf5 (MD5) Previous issue date: 1990","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:49:02Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:22:16-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission","U of I Only"],"dc:identifier":["AAI9026184","(UMI)AAI9026184","http://hdl.handle.net/2142/21183"],"dc:language":["eng"],"dc:rights":["Copyright 1990 Frauenhoff, Mary Mills"],"dc:subject":["Chemistry, Biochemistry","Chemistry, Inorganic"],"dc:title":["Semisynthetic cytochrome c site-67 substitutions"],"dc:type":["text"],"thesis:degree_discipline":["Chemistry"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:17Z"}