Characterization of mesoscale coiled-coil peptide-porphyrin complexes.
Photoelectronically conductive self-assembling peptide-porphyrin assemblies have great potential in their use as biomaterials, owing largely to their environmentally responsive properties. We have successfully designed a coiled-coil peptide that can self-assemble to form mesoscale filaments and serve as a scaffold for porphyrin interaction. In our earlier work, peptide-porphyrin-based biomaterials were formed at neutral pH, but the structures were irregular at the nano- to microscale size range, as judged by atomic force microscopy. We identified a pH in which mesoscale fibrils were formed, taking advantage of the types of porphyrin interactions that are present in well-characterized J-aggregates. We used UV-visible spectroscopy, circular dichroism spectropolarimetry, fluorescence spectroscopy, and atomic force microscopy to characterize these self-assembling biomaterials. We propose a new assembly paradigm that arises from a set of unique porphyrin-porphyrin and porphyrin-peptide interactions whose structure may be readily modulated by changes in pH or peptide concentration.
Department of Biology, Haverford College, Haverford, Pennsylvania 19041, United States.
Brian J
BJ
Pepe-Mooney
Bashkim
B
Kokona
Robert
R
Fairman
D001672:Biocompatible Materials / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D002942:Circular Dichroism; D006863:Hydrogen-Ion Concentration; D018625:Microscopy, Atomic Force; D008958:Models, Molecular; D046912:Multiprotein Complexes / Q000032:analysis* / Q000502:physiology; D010455:Peptides / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D011166:Porphyrins / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D017433:Protein Structure, Secondary; D013057:Spectrum Analysis
D001672:Biocompatible Materials; D046912:Multiprotein Complexes; D010455:Peptides; D011166:Porphyrins