Structural Conversion Rate Changes of Recombinant Bovine Prion by Designed Synthetic Peptides

Separation of Peptides Having Structures and Derivatives of Mimosine, a Nonproteinogenic Amino Acid, by a Novel Reverse-Phase HPLC Column Packed With Wide-Pore Silica

“…By using the present columns, we have successfully prepared a high quality of structured peptides and developed a novel assay method for PrP structural conversion. [5] For additional applications, we have found that this column can discriminate diastereomers of mimosine (Mim), a nonproteinogenic amino acid isolated from natural resources [6] and have confirmed the chiral purity. The antitumor effect, [7] potently inhibiting lung cancer cell proliferation [8] and the tyrosinase inhibitory activities of Mim [9] have been reported.…”

“…RinkAmide ChemMatrix was purchased from PCAS BioMatrix Inc (Quebec, Canada). N,N-diisopropyl ethylamine, TFA, N,N-dimethylformamide (DMF), 1,8-diazobicyclo [5,4, 0]-undec-7-ene (DBU), and other solvents and chemicals were of analytical grade from Nacalai Tesque (Kyoto, Japan). Peptide-chain assembly was performed on an automated synthesizer, PSSM-8 (Shimadzu, Kyoto, Japan), or a manual synthesizer, PetiSyzer (HiPep Labs).…”

Design and syntheses of peptides which induce or enhance structural changes of recombinant bovine prion protein (rbPrP) and discovery of peptides from bovine brain which accelerate structural conversions of rbPrP

“…7 We have found that the influence on aggregation has been evaluated from determination of the lag-time when the Thioflavin T (ThT) fluorescence change starts to increase and the kinetics from the incremental change in the fluorescent intensities until a plateau is reached. 6 Peptides P2-P5 ( Fig. 1) and HPPSH decrease the lag-time, but the other peptides have no or very little influence.…”

“…We have shown that the co-existence of certain peptides influenced the kinetic rate of aggregation and the lag-time of fibril formation of rbPrP. 6 There are peptides which influence, more precisely accelerate, the structural change of recombinant prion protein and this model may mimic the formation of the pathogenic isoform of prion protein (PrP Sc ). By using the above assay method to monitor structural changes in rbPrP the responsible peptides for the structural conversion have seen searched from partial digests of bovine brain.…”

“…1). The secondary structures of the present peptides were characterized by circular dichroism spectra, which were described in, 6 taking into account the influence of a hydrophobic environment as described in. 7 We have found that the influence on aggregation has been evaluated from determination of the lag-time when the Thioflavin T (ThT) fluorescence change starts to increase and the kinetics from the incremental change in the fluorescent intensities until a plateau is reached.…”