Structural characterization and 5′-mononucleotide binding of polyalanine β-sheet complexes

✍ Scribed by Enrique Pérez-Payá; Behrouz Forood; Richard A. Houghten; Sylvie E. Blondelle

• Book ID: 102659480
• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 581 KB
• Volume: 9
• Category: Article
• ISSN: 0952-3499
• DOI: 10.1002/(sici)1099-1352(199634/12)9:5/6<488::aid-jmr289>3.0.co;2-f

✦ Synopsis

A study was initiated into the formation and stability of highly soluble p-sheet macrostructures. Such P-sheet macrostructures are useful model systems for the study of the biological function of the hydrophobic core of proteins and for the de ~O Y O design of novel catalytic mimics. In the current study, a 16-mer-alanine-based peptide (Ac-KA,,K-NHJ that is highly water soluble and adopts an extremely stable macromolecular p-sheet structure was synthesized. A tyrosine-containing analog (Ac-KYA,,K-NH,) was used to study the tertiary structure of the complex by circular dichroism spectroscopy, while the influence of the charges on the complex formation and binding affinity was evaluated using a zwitterionic analog (Ac-KEA,,KE-NH& Both the secondary and tertiary structures of the f3-sheet complex were stable to denaturants, as demonstrated by far-and nearultraviolet circular dichroism spectroscopy. Binding studies with mononucleotides have shown that the &sheet complex binds to molecules through both hydrophobic and electrostatic interactions. These intrinsic properties were found to be a prerequisite for the observed enhanced cleavage of phosphodiester bonds.