eprintid: 17789 rev_number: 16 userid: 1419 dir: disk0/00/01/77/89 datestamp: 2013-03-20 16:43:59 lastmod: 2019-02-02 16:55:13 status_changed: 2013-03-20 16:43:59 type: article metadata_visibility: show item_issues_count: 0 eprint_status: archive creators_name: Boyden, MN creators_name: Asher, SA creators_email: creators_email: asher@pitt.edu creators_id: creators_id: ASHER title: UV Raman studies of peptide conformation demonstrate that betanova does not cooperatively unfold ispublished: pub divisions: sch_as_chemistry full_text_status: public abstract: We used UV resonance Raman spectroscopy (UVRR) excited within the peptide bond π→π*electronic transitions and within the aromatic amino acid π→π*electronic transitions to examine the temperature dependence of the solution conformation of betanova, a 20-residue β-sheet polypeptide [Kortemme, T., Ramirez-Alvarado, M., and Serrano, L. (1998) Science 281, 253-256]. The 206.5 nm excited UVRR enhances the amide vibrations and demonstrates that betanova has a predominantly β-sheet structure between 5 and 82 °C. The 229 nm excited UVRR, which probes the tyrosine and tryptophan side chain vibrations, shows an increase in the solvent exposure of the tryptophan side chains as the temperature is increased. Our results are consistent with the existence of an intermediate state similar to that calculated by Bursulaya and Brooks [Bursulaya, B. D., and Brooks, C. L. (1999) J. Am. Chem. Soc. 121, 9947-9951] and exclude the previously proposed two-state cooperative folding mechanism. Betanova's structure appears to be molten globule over the 3-82 °C temperature range of our study. date: 2001-11-13 date_type: published publication: Biochemistry volume: 40 number: 45 pagerange: 13723 - 13727 refereed: TRUE issn: 0006-2960 id_number: 10.1021/bi011505k pmid: 11695921 mesh_headings: Circular Dichroism mesh_headings: Peptides--chemistry mesh_headings: Protein Folding mesh_headings: Protein Structure, Secondary mesh_headings: Proteins--chemistry mesh_headings: Spectrophotometry, Ultraviolet mesh_headings: Spectrum Analysis, Raman--methods chemical_names: Peptides chemical_names: Proteins chemical_names: betanova protein, synthetic citation: Boyden, MN and Asher, SA (2001) UV Raman studies of peptide conformation demonstrate that betanova does not cooperatively unfold. Biochemistry, 40 (45). 13723 - 13727. ISSN 0006-2960 document_url: http://d-scholarship-dev.library.pitt.edu/17789/1/licence.txt