Polymorphisms at Amino Acid Residues 141 and 154 Influence Conformational Variation in Ovine PrP

Table 2

Quantitative changes in molar ellipticity values of sarkosyl-treated ovine recombinant PrP. Batches of ovine recombinant PrP ALRQ (𝑛=5) and ALHQ (𝑛=3) were analysed by CD spectroscopy following treatment with sarkosyl as described in Section 2. Results are mean ± standard deviation molar ellipticity values at wavelengths characteristic for α-helical (193 nm, 208 nm, and 222 nm) and β-sheet (195 nm and 218 nm) proteins. Figures in brackets show percentage change in molar ellipticity values between sarkosyl- and water-treated samples. Statistical analyses of the data for individual PrP genotypes were performed using one-way ANOVA with Tukey HSD (honestly significant difference) for post hoc analysis or the two-tailed Student’s 𝑡-test (unpaired samples) for analyses between genotypes using the Prism 4 software package (GraphPad).

Ovine PrP	Sarkosyl	Molar ellipticity (deg·cm^2·dmol^−1) × 10^−3
		193 nm	208 nm	222 nm	195 nm	218 nm
ALRQ	None	14032 ± 2978	−9944 ± 642	−8879 ± 694	11779 ± 2205	−9624 ± 853
	0.005%	10530 ± 2176; (25%)	−6489 ± 1077*; (35%)	−7195 ± 486*; (19%)	9102 ± 1886; (23%)	−7562 ± 716*; (21%)
	0.008%	7708 ± 2012*; (45%)	−3576 ± 1311*; (64%)	−4706 ± 1077*; (47%)	6369 ± 1106*; (46%)	−4819 ± 1354*; (50%)
ALHQ	None	12690 ± 1952	−9988 ± 1713	−8703 ± 551	10993 ± 3150	−9643 ± 695
	0.005%	10454 ± 1594; (18%)	−7506 ± 1290; (25%)	−8274 ± 662^†; (5%)	10131 ± 1882; (8%)	−8969 ± 448^†; (7%)
	0.008%	10833 ± 3237; (15%)	−5315 ± 1962*; (47%)	−7786 ± 831^†; (11%)	9595 ± 1704^†; (13%)	−7945 ± 602^*†; (18%)

^∗𝑃<0.05 for sarkosyl treatment in comparison with no sarkosyl treatment.
^†𝑃<0.05 for ALRQ versus ALHQ.