Fate of prions in soil: Interaction of a recombinant ovine prion protein with synthetic humic-like mineral complexes

Interaction of a Recombinant Prion Protein with Organo-Mineral Complexes as Assessed by FT-IR and CPMAS 13C NMR Analysis

“…Organo-mineral-recPrP complexes used in this study were prepared according to the methodology described by Rao et al [13]. Briefly, either 3 or 5 mM catechol (Cat3 and Cat5, respectively), 0.5 mg ml -1 recPrP and 5 mg ml -1 birnessite in 0.1 M sodium acetate buffer at pH 5.5 were incubated in different systems.…”

“…Supernatants and insoluble precipitates were separated by centrifugation (30 min at 10,000 rev min -1 and 4 °C). Residual catechol and recPrP concentrations were evaluated by HPLC analysis [13] with a Shimadzu instrument equipped with UV-Vis variable-wavelength absorbance detector, set at 280 and 222 nm respectively.…”

“…The pellets were washed twice with 0.02 M NaCl, twice with double-distilled water, freeze-dried and stored at 4 °C [13].…”

“…Either the infective or the benign forms of prion proteins are able to strongly bind to mineral [8][9][10][11][12] and organic soil components [13][14][15]. PrP Sc can be displaced from environmental compartments to soil, but this does not necessarily decrease its infectivity [10,16].…”

“…Interaction with already-formed HS could lead to superficial protein sorption, while entrapment phenomenon could arise if the protein is involved in the humification process [13]. In general, immobilized proteins may result more stable than free forms; for instance enzymes in humic complexes are more resistant to thermal denaturation and proteolysis than the respective free enzymes [20].…”