NR ARFA
AU Müller,H.; Riesner,D.
TI Thermostability of prion rods is raised by lipids
QU TSE-Forum, 4. Kongress - Nationale TSE-Forschungsplattform, Düsseldorf 28.10.-29.10.2004, Poster INAK-03
PT Konferenz-Poster
AB
To determine degradation factors for 263K prion rods or recombinant prion protein recPrP(90-231) from Syrian hamster at different temperatures up to 170 ° and in presence or absence of lipids and glycerine an inactivation system established by Appel et al. (1) was successfully adapted for application of a 50 ml pressure reactor.
Comparing degradation experiments with and without bovine edible tallow it was confirmed that actually lipids have a profound capacity to increase the stability of prions against heat degradation. At higher temperatures in addition to the PrP monomer bands an increased tendency to form aggregates of higher molecular mass was observed. In presence of water the protective effect of lipids decreases with increasing temperature because the non-convalent associations with lipids that protect prions against hydrolytic attack are gradually lost with increasing temperature. In contrast, in presence of glycerine the protective effect does not decrease with increasing temperature. In a mixture containing 90 % water and 10 % glycerine the degradations factors at all temperatures are as low as in pure tallow. In pure glycerine the heat stability of prions is even further increased. The stability-increasing effect of fat seems not to be basically based on the presence of fatty acids rather the presence of glycerine contributes to the main-stabilising effects.
Moreover, it became obvious that the higher the volume of the heat-treated lipid sample and thus the lower the surface volume ratio of the reactor content the lower the PrP degradation. Consequently, the degradation of PrP seems to be influenced by the inner reactor surface area exposed during heat inactivation.
The results will be interpreted also with respect to the safety of oleochemical production processes.
(1) J Gen Virol. 2001;82:465-73
AD Müller, Henrik; Riesner, Detlev, Institute for Physical Biology, Heinrich Heine - University Düsseldorf, 26.12 U1 R.90, Universitätsstraße 1, D-40225 Düsseldorf, phone +49 211 81-15314
SP englisch
PO Deutschland
OR Tagungsband