Impact of Strand Number on Parallel beta-Sheet Stability.
Kung, V.M., Cornilescu, G., Gellman, S.H.(2015) Angew Chem Int Ed Engl 54: 14336-14339
- PubMed: 26457984 
- DOI: https://doi.org/10.1002/anie.201506448
- Primary Citation of Related Structures:  
2N4N, 2N6H, 2N6I - PubMed Abstract: 
We have examined whether parallel β-sheet secondary structure becomes more stable as the number of β-strands increases, via comparisons among peptides designed to adopt two- or three-stranded parallel β-sheet conformations in aqueous solution. Our three-strand design is the first experimental model of a triple-stranded parallel β-sheet. Analysis of the designed peptides by nuclear magnetic resonance (NMR) and circular dichroism (CD) spectroscopy supports the hypothesis that increasing the number of β-strands, from two to three, increases the stability of the parallel β-sheet. We present the first experimental evidence for cooperativity in the folding of a triple-stranded parallel β-sheet, and we show how minimal model systems may enable experimental documentation of characteristic properties, such as CD spectra, of parallel β-sheets.
Organizational Affiliation: 
Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, WI 53706 (USA).