Scrapie‐infected cells, isolated prions, and recombinant prion protein: A comparative study

Abstract
Fourier ‐transform infrared microscopic spectra of scrapie‐infected nervous tissue measured at high spatial resolution (∼6 μm) were compared with those obtained from the purified, partly proteinase K digested scrapie isoform of the prion protein isolated from nervous tissue of hamsters infected with the same scrapie strain (263K) to elucidate similarities/dissimilarities between prion structure investigated in situ and ex vivo. A further comparison is drawn to the recombinant Syrian hamster prion protein SHaPrP90–232 after in vitro conformational transition from the predominantly α‐helical isoform to β‐sheet‐rich structures. It is shown that prion protein structure can be investigated within tissue and that detectability of regions with elevated β‐sheet content as observed in microspectra of prion‐infected tissue strongly depends on spatial resolution of the experiment. © 2004 Wiley Periodicals, Inc. Biopolymers, 2004