{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/25637"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/25637","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Dynamics of carbon monoxide binding to protoheme and heme c octapeptide","abstract":"Made available in DSpace on 2011-07-05T14:32:47Z (GMT). No. of bitstreams: 1 1977_chan.pdf: 2340958 bytes, checksum: d7a233669c5ad7b4e20e6fe3d2614510 (MD5) Previous issue date: 1977","abstract_html":"Made available in DSpace on 2011-07-05T14:32:47Z (GMT). No. of bitstreams: 1 1977_chan.pdf: 2340958 bytes, checksum: d7a233669c5ad7b4e20e6fe3d2614510 (MD5) Previous issue date: 1977","abstract_has_math":false,"creators":["Chan, Shirley Suiling"],"institution":null,"degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Physics","degree_department":null,"school":null,"contributors":["Frauenfelder, Hans"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-07-05T14:32:47Z","date_published":"2011-07-05T14:32:47Z","updated_at":"2026-07-22T22:25:24Z","subjects":["carbon monoxide binding","protoheme","heme octapeptide","heme binding dynamics","photodissociation"],"languages":["en"],"rights":["1977 Shirley SuiLing Chan"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["2738162"],"render_values":[{"text":"2738162","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/25637","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Frauenfelder, Hans"]},{"key":"dc:creator","label":"Author","values":["Chan, Shirley Suiling"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-07-05T14:32:47Z","10000-01-01","1977"]},{"key":"dc:type","label":"Dc Type","values":["Dissertation / Thesis","text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Physics"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["carbon monoxide binding","protoheme","heme octapeptide","heme binding dynamics","photodissociation"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["1977 Shirley SuiLing Chan"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["2738162","http://hdl.handle.net/2142/25637"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Made available in DSpace on 2011-07-05T14:32:47Z (GMT). No. of bitstreams: 1 1977_chan.pdf: 2340958 bytes, checksum: d7a233669c5ad7b4e20e6fe3d2614510 (MD5) Previous issue date: 1977","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Carolyn Mead (cmead2@illinois.edu) on 2011-07-05T14:32:47Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:32:31-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: Thesis","\"Protoheme and heme a octapeptide rebinding of carbon monoxide after photodissociation have been observed at temperatures from 5 to 340 K for times from 2 ~s to 1 ks. Below 80 K, binding is nonexponentia1 in time and CO-concentration independent, above 230 K exponential and the rate is CO-concentration proportional. A model is proposed in which the carbon monoxide, moving from the solvent to the binding site at the ferrous heme iron, encounters two successive barriers. The outer is formed by the solvent, the inner is a property of the heme and probably connected to the transition of the iron from the spin-2 deoxy to the spin-O carbon monoxide state. The temperature dependence of the two processes yields all activation enthalpies and entropies for the two barriers. The nonexponential rebinding observed at low temperatures implies that the inner barrier possesses distributed activation enthalpy and entropy. The enthalpy spectrum and the entropy spread are determined. The spectrum demonstrates that heme exists in many different conformational states. At low temperatures, these states are frozen; above about 230 K, rapid conformational relaxation renders rebinding exponential. Below about 150 K, a new fast process of 10 us duration is observed for heme a octapeptide; its optical spectrum is different from the one corresponding to the transition from 5=2 to S-O. A possible explanation is that it involves an intermediate state-with 5=1. Below 15 K. quantum-mechanical molecular tunneling dominates. The tunneling rate yields the width of the innermost barrier. Earlier experiments on carbon monoxide bin41ng to myoglobin had provided evidence for four barriers. The present results imply that the innermost barrier in myoglobin is caused\"\" by the heme, the outermost by \"\"the solvent. and the two intermediate ones by the globin.\"","Submitted by Carolyn Mead (cmead2@illinois.edu) on 2011-07-05T14:32:47Z No. of bitstreams: 1 1977_chan.pdf: 2340958 bytes, checksum: d7a233669c5ad7b4e20e6fe3d2614510 (MD5)","Thesis","U of I Only"]},{"key":"dc:title","label":"Title","values":["Dynamics of carbon monoxide binding to protoheme and heme c octapeptide"]}]}],"canonical_facts":{"dc:contributor":["Frauenfelder, Hans"],"dc:creator":["Chan, Shirley Suiling"],"dc:date":["2011-07-05T14:32:47Z","10000-01-01","1977"],"dc:description":["Made available in DSpace on 2011-07-05T14:32:47Z (GMT). No. of bitstreams: 1 1977_chan.pdf: 2340958 bytes, checksum: d7a233669c5ad7b4e20e6fe3d2614510 (MD5) Previous issue date: 1977","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Carolyn Mead (cmead2@illinois.edu) on 2011-07-05T14:32:47Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:32:31-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: Thesis","\"Protoheme and heme a octapeptide rebinding of carbon monoxide after photodissociation have been observed at temperatures from 5 to 340 K for times from 2 ~s to 1 ks. Below 80 K, binding is nonexponentia1 in time and CO-concentration independent, above 230 K exponential and the rate is CO-concentration proportional. A model is proposed in which the carbon monoxide, moving from the solvent to the binding site at the ferrous heme iron, encounters two successive barriers. The outer is formed by the solvent, the inner is a property of the heme and probably connected to the transition of the iron from the spin-2 deoxy to the spin-O carbon monoxide state. The temperature dependence of the two processes yields all activation enthalpies and entropies for the two barriers. The nonexponential rebinding observed at low temperatures implies that the inner barrier possesses distributed activation enthalpy and entropy. The enthalpy spectrum and the entropy spread are determined. The spectrum demonstrates that heme exists in many different conformational states. At low temperatures, these states are frozen; above about 230 K, rapid conformational relaxation renders rebinding exponential. Below about 150 K, a new fast process of 10 us duration is observed for heme a octapeptide; its optical spectrum is different from the one corresponding to the transition from 5=2 to S-O. A possible explanation is that it involves an intermediate state-with 5=1. Below 15 K. quantum-mechanical molecular tunneling dominates. The tunneling rate yields the width of the innermost barrier. Earlier experiments on carbon monoxide bin41ng to myoglobin had provided evidence for four barriers. The present results imply that the innermost barrier in myoglobin is caused\"\" by the heme, the outermost by \"\"the solvent. and the two intermediate ones by the globin.\"","Submitted by Carolyn Mead (cmead2@illinois.edu) on 2011-07-05T14:32:47Z No. of bitstreams: 1 1977_chan.pdf: 2340958 bytes, checksum: d7a233669c5ad7b4e20e6fe3d2614510 (MD5)","Thesis","U of I Only"],"dc:identifier":["2738162","http://hdl.handle.net/2142/25637"],"dc:language":["en"],"dc:rights":["1977 Shirley SuiLing Chan"],"dc:subject":["carbon monoxide binding","protoheme","heme octapeptide","heme binding dynamics","photodissociation"],"dc:title":["Dynamics of carbon monoxide binding to protoheme and heme c octapeptide"],"dc:type":["Dissertation / Thesis","text"],"thesis:degree_discipline":["Physics"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."]},"updated_at":"2026-07-22T22:25:24Z"}