Publications by authors named "Sayuri Takeo"

In this study, we have identified two novel peptides, 19Ac (comprising residues 91-105) and 20Ac (encompassing residues 96-110), from a systematically designed peptide library based on the Hepatitis B virus (HBV) core protein, that inhibit the assembly of HBV capsid. Peptide 20Ac exhibited about twofold the inhibitory potency of 19Ac and proved effective against both standard and morphothiadin (GLS4)-resistant HBV strains. Molecular dynamics simulations revealed that despite their overlapping sequence, 19Ac and 20Ac bonded to different regions of the core protein, thereby inhibiting capsid assembly through distinct mechanisms.

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Described here is the synthetic, spectroscopic, crystallographic, and computational analysis of a series of peptidomimetics containing l-Xaa-d-Yaa-type ()-chloroalkene dipeptide isosteres (CADIs) that were measured in an investigation of the β-turn mimicry of this peptide bond surrogate. We found that the 1,3-allylic strain across the chloroalkene moiety engenders the hyperconjugative interactions between the chloroalkene moiety and the C-H bonding or antibonding orbitals of the C-H bonds in allylic positions. These effects contribute significantly to the stabilization of β-turn structures.

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Stereoselective and efficient synthesis of Gly-Gly-type ()-methylalkene and ()-chloroalkene dipeptide isosteres is realized by organocuprate-mediated single electron transfer reduction. The synthetic isosteres can be used in Fmoc-based solid phase peptide synthesis, resulting in the preparation of the 14-mer RGG peptidomimetics containing an ()-methylalkene or a ()-chloroalkene unit.

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