Phospholipids influence the aggregation of recombinant ovine prions. From rapid extensive aggregation to amyloidogenic conversion.

The transformation of prion protein (PrP) into its insoluble amyloid form correlates with neurodegeneration in transmissible spongiform encephalopathies. PrP is connected to the neuronal membrane by a covalently-linked glycosylphosphatidylinositol (GPI) anchor. The current study demonstrates that phosphatidylinositol and phosphatidylethanolamine in low concentrations (0.

Cu(II) induces small-size aggregates with amyloid characteristics in two alleles of recombinant ovine prion proteins.

One of symptoms of transmissible spongiform encephalopathies is associated with the transformation of normal cellular prion protein, PrP, in its amyloid isoform resistant to proteolytic cleavage. The present study shows that interaction with copper ions converts both monomeric recombinant scrapie-susceptible PrP-VRQ and scrapie-resistant PrP-ARR variants into protease-resistant soluble oligomers with amyloid characteristics -- dominant beta-sheet secondary structure and interaction with thioflavine S. In contrast, binding of zinc ions resulting in the same resistance to proteolysis does not provoke transformation of alpha-helical monomeric structure of both PrP polymorphic variants.

Copper-dependent degradation of recombinant ovine prion protein. Phosphatidylinositol stimulates aggregation and copper-driven disappearance of prion protein.

Prion protein (PrP) plays an important role in cell protection from oxidative stress due to its action as copper-chelating protein. The present study demonstrates that PrP participates in reductions of Cu2+ to Cu+ ions, and that this process results in fragmentation of protein. The interaction with phosphatidylinositol, a natural phospholipid moiety bound to PrP, strongly enhances recombinant PrP aggregation and degradation.

Hydrolysis of the amyloid prion protein and nonpathogenic meat and bone meal by anaerobic thermophilic prokaryotes and streptomyces subspecies.

Transmissible spongiform encephalopathies are caused by accumulation of highly resistant misfolded amyloid prion protein PrPres and can be initiated by penetration of such pathogen molecules from infected tissue to intact organism. Decontamination of animal meal containing amyloid prion protein is proposed thanks to the use of proteolytic enzymes secreted by thermophilic bacteria Thermoanaerobacter, Thermosipho, and Thermococcus subsp. and mesophilic soil bacteria Streptomyces subsp.