Chemistry Faculty Publications
Document Type
Article
Abstract
AQ-Pal14 is a 30-residue polypeptide that was designed to form an alpha-helical coiled coil that contains a metal-binding 4-pyridylalanine residue on its solvent-exposed surface. However, characterization of this peptide shows that it exists as a three-stranded coiled coil, not a two-stranded one as predicted from its design. Reaction with cobalt(III) protoporphyrin IX (Co-PPIX) produces a six-coordinate Co-PPIX(AQ-Pal 14)(2) species that creates two coiled-coil oligomerization domains Coordinated to opposite laces of the porphyrin ring. It is found that this species undergoes a buffer-dependent Self-assembly process: nanometer-scale globular materials were formed when these components were reacted in unbuffered H(2)O, while millimeter-scale, rod-like materials were prepared when the reaction was performed in phosphate buffer (20 mM, pH 7). It is suggested that assembly of the globular material is dictated by the conformational properties of the coiled-coil forming AQ-Pal14 peptide, whereas that a the rod-like material involves interactions between Co-PPIX and phosphate ion.
Copyright Statement
Publisher PDF
Repository Citation
Zaytsev, Daniil V.; Xie, Fei; Mukherjee, Madhumita; Bludin, Alexey; Demeler, Borries; Breece, Robert M.; Tierney, David L.; and Ogawa, Michael Y., "Nanometer To Millimeter Scale Peptide-porphyrin Materials" (2010). Chemistry Faculty Publications. 124.
https://scholarworks.bgsu.edu/chem_pub/124
Publication Date
10-2010
Publication Title
Biomacromolecules
DOI
https://doi.org/10.1021/bm100540t
Start Page No.
2602
End Page No.
2609