Peptide-urea interactions as observed in diketopiperazine-urea cocrystal
M M Thayer1, R C Haltiwanger, V S Allured
1Department of Chemistry and Biochemistry, University of Colorado, Boulder 80309-0215.
Abstract:
In order to develop a more complete understanding of urea induced protein denaturation we have investigated the crystal structure of urea with the cyclic dipeptide diketopiperazine. This structure, determined to an R factor of 8.1%, shows extensive hydrogen bonding between urea and the peptide groups of diketopiperazine. These studies support a model where hydrogen bonding plays an important contribution in urea-induced protein denaturation. In the companion paper we present thermodynamic data for urea-peptide interactions in aqueous solution that further support this model.
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