Turn and helical peptide handedness governed exclusively by side-chain chiral centers.
We have examined the preferred 3D structure of homopeptides based on an alpha-amino acid lacking the asymmetry at the alpha-carbon but exhibiting chirality in the side chains (at the two beta-carbons). These joint stereochemical properties are remarkably unusual for an alpha-amino acid. To this end, we carried out an experimental investigation by X-ray diffraction and NMR spectrometry. The results point to a well-defined relationship between screw sense of the turn and helix structures formed and side-chain configurations.
Royo
Soledad
S
Department of Organic Chemistry, ICMA, University of Zaragoza-CSIC, 50009 Zaragoza, Spain.
De Borggraeve
Wim M
WM
Peggion
Cristina
C
Formaggio
Fernando
F
Crisma
Marco
M
Jiménez
Ana I
AI
Cativiela
Carlos
C
Toniolo
Claudio
C
D003521:Cyclopropanes / Q000737:chemistry*; D008958:Models, Molecular; D010455:Peptides / Q000737:chemistry*; D017433:Protein Structure, Secondary; D013237:Stereoisomerism; D014961:X-Ray Diffraction
C481928:(2S,3S)-1-amino-2,3-diphenylcyclopropanecarboxylic acid; D003521:Cyclopropanes; D010455:Peptides