Rotatory dispersion and circular dichroism of low-molecular-weight poly-γ-benzyl-L-glutamate

✍ Scribed by Toyoko Imae; Shoichi Ikeda

• Publisher: Wiley (John Wiley & Sons)
• Year: 1972
• Tongue: English
• Weight: 393 KB
• Volume: 11
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.1972.360110215

✦ Synopsis

Synopsis

llotatory dispersion and circular dichroism of low-molecular-weight poly-7-benzyl-Lglutamate, which was prepared from the ,V-carboxyanhydride by n-hexylamine initiation a t [A]/[I] 3, 4, and 8, have been nieasured in ethylene dichloride and dioxane a t difierent concentrations. The rotatory properties of the polypeptides are all characterihed by a trough at 233 mp of a negative Cotton effect or by a negative circular dichroic band a t 223 mp. With increasing A/I value or concentration, dextrorotation increases and the negative dichroic band becomes deeper. Both the trough magnitude and the negative ellipticity are linearly dependent OP the content of p-structure, and the rotatory parameters for the pure p-structure are estimated by extrapolation of the linear relations. Circular dichroisni arid infrared spectra of the polypeptides have also been measured in trifluoroethanol, and the effect of solvents on the polypeptide conformation is discussed.