A nuclear magnetic resonance study and proton exchange of poly-L-alanine.
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Chemical Phenomena↗
Biomedical subjects
L Mandelkern
Publications and source records attributed to L Mandelkern.
MECHANISM OF CONTRACTION IN THE MUSCLE FIBER-ATP SYSTEM.
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Journal Article↗
Influence of conformational isomers on the circular dichroism of poly(L-prolyglycine).
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Circular Dichroism↗
The observation of cis residues in poly(L-proline) in aqueous solution.
Proton Fourier transform NMR spectra at 270 MHz were obtained for three different molecular weight samples of poly(L-proline) in D2O. A weak, but clearly discernable, resonance at 4.3 ppm was observed in each case with an integrated intensity about 2-3% of the Calpha trans proton resonance. Based on the Torchia-Bovey assignment this resonance is attributed to the Calpha cis proton. The presence of cis residues, even in this small concentration, necessitates a reexamination of the conformational properties of this polymer. Definite conclusions cannot be reached from spectra obtained in organic solvents because of the much smaller separation between the cis and trans resonances.
Isomerism↗