2026-09-22T17:51:07Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/84495 2023-07-11 col_2142_5131 col_2142_14789 com_2142_5130 com_2142_14788 com_2142_8903

Kenneth S. Suslick Rosenblatt, Michael Maurice 2015-09-25T22:14:48Z 2015-09-25T22:14:48Z 10000-01-01 2000 2000 Addition of disulfide bridges and ionic contacts. We have synthesized and characterized a new class of heme-peptide complexes using disulfide-linked tweezers and cyclic peptides. The binding affinities, helicities, and mechanism of binding of linear, tweezers, and cyclic peptides to [Fe III(coproporphyrin-I)]+ have been determined. We have incorporated disulfide bridges between amphiphilic peptides to make tweezers---and even cyclic-peptides that bind heme extremely strongly, roughly 5 x 106 times more strongly than histidine itself. CD studies show that the cyclic peptide heme complexes are completely a-helical. Paramagnetic NMR shows that the 15-mer peptides bind sequentially, with an observable mono-peptide, high-spin intermediate. In contrast, the cyclic peptide complexes ligate both imidazoles cooperatively to the heme, producing only a low spin complex. Electrochemical measurements of the E1/2 of the FeIII(coproporphyrin-I) complexes of these peptides are all a fairly low potentials, ranging from -215 to -252 mV vs. NHE at pH 7. Addition of salt contacts to the design, resulted in the production of a highly helical complex. This peptide, bound to a diamagnetic and water soluble CoIII(coproporphyrin-I), has a stability toward denaturation of 3 kcal/mole. Made available in DSpace on 2015-09-25T22:14:48Z (GMT). No. of bitstreams: 2 license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5) 9990126.pdf: 15161995 bytes, checksum: 80b49bbfe04dcc86d84d61bbf56cff06 (MD5) Previous issue date: 2000 Embargo set by: Seth Robbins for item 85776 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs U of I Only 411 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2000. http://hdl.handle.net/2142/84495 (MiAaPQ)AAI9990126 eng Chemistry, Analytical Myoglobin Microsperes and Metalloporphyrin -Peptide Complexes text Chemistry Chemistry University of Illinois at Urbana-Champaign Dissertation Ph.D.