Cold-Denatured Ensemble of Apomyoglobin: Implications for the Early Steps of Folding

@article{citeulike:2235488, abstract = {Abstract: The dynamics of protein-refolding experiments initiated by a temperature jump depend critically on the nature of the initial cold-denatured ensemble. The cold-denatured state of equine apomyoglobin has been investigated in aqueous buffers by near- and far-UV circular dichroism, fluorescence, infrared, and NMR spectroscopies at temperatures ranging from -20 to 98 C. Cold denaturation of apomyoglobin is well described by a cooperative transition below 3 C and differs in many aspects from acid-induced unfolding. As a reference system, the N-terminal A-peptide fragment of equine apomyoglobin has also been studied in aqueous and trifluoroethanol solutions. The A-peptide has a low helix-forming propensity in the absence of any stabilizing tertiary interactions. The results show that cold denaturation breaks the AGH-hydrophobic interface of equine apomyoglobin. Furthermore, at least some GH-helical structure appears to be preserved at the expense of the less stable A-helix.}, address = {School of Chemical Sciences and Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana, Illinois 61801}, author = {Sabelko, J. and Ervin, J. and Gruebele, M. }, citeulike-article-id = {2235488}, doi = {10.1021/jp973178p}, journal = {J. Phys. Chem. B}, keywords = {cold-denaturation, experiment, hydrophobicity, proteins, thermodynamics}, month = {March}, number = {10}, pages = {1806--1819}, posted-at = {2008-01-15 16:35:45}, priority = {2}, title = {Cold-Denatured Ensemble of Apomyoglobin: Implications for the Early Steps of Folding}, url = {http://dx.doi.org/10.1021/jp973178p}, volume = {102}, year = {1998} }

TY - JOUR ID - citeulike:2235488 L3 - citeulike-article-id:2235488 TI - Cold-Denatured Ensemble of Apomyoglobin: Implications for the Early Steps of Folding JF - J. Phys. Chem. B VL - 102 IS - 10 SP - 1806 EP - 1819 AD - School of Chemical Sciences and Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana, Illinois 61801 N2 - Abstract: The dynamics of protein-refolding experiments initiated by a temperature jump depend critically on the nature of the initial cold-denatured ensemble. The cold-denatured state of equine apomyoglobin has been investigated in aqueous buffers by near- and far-UV circular dichroism, fluorescence, infrared, and NMR spectroscopies at temperatures ranging from -20 to 98 C. Cold denaturation of apomyoglobin is well described by a cooperative transition below 3 C and differs in many aspects from acid-induced unfolding. As a reference system, the N-terminal A-peptide fragment of equine apomyoglobin has also been studied in aqueous and trifluoroethanol solutions. The A-peptide has a low helix-forming propensity in the absence of any stabilizing tertiary interactions. The results show that cold denaturation breaks the AGH-hydrophobic interface of equine apomyoglobin. Furthermore, at least some GH-helical structure appears to be preserved at the expense of the less stable A-helix. KW - cold-denaturation KW - experiment KW - hydrophobicity KW - proteins KW - thermodynamics AU - Sabelko, J AU - Ervin, J AU - Gruebele, M PY - 1998/03/05/ UR - http://dx.doi.org/10.1021/jp973178p ER -