Spectroscopic analysis demonstrates carbon-13 NMR chemical shifts of amino acid residues in model tetrapeptides, highlighting suitable random-coil reference benchmarks for polypeptide conformation.
The 13 C nmr chemical shifts of the common amino acid residues were measured in D 2 O solutions of the linear tetrapeptides H‐Gly‐Gly‐X‐ L ‐Ala‐OH. For Asp, Glu, Lys, Tyr and His, the titration shifts arising from the ionization of te amino acid side chains were also obtained. These data are compared with the corresponding 13 C chemical shifts in the protected tetrapeptides CF 3 CO‐Gly‐Gly‐X‐ L ‐Ala‐OCH 3 , the linear pentapeptides H‐Gly‐Gly‐X‐Gly‐Gly‐OH, and the free amino acids. On this basism the selection of suitable “random coil” 13 C chemical shifts for conformational studies of polypeptides chain is discussed.
No takes yet. Share an insight, caveat, or question.
Richarz et al. (1978) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: