Conformation of poly-L-glutamate is independent of ionic strength.
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ABSTRACT:
SUBMITTER: Xiong K
PROVIDER: S-EPMC3288237 | biostudies-literature | 2012 Mar
REPOSITORIES: biostudies-literature
Publications
Conformation of poly-L-glutamate is independent of ionic strength.
Xiong Kan K Ma Lu L Asher Sanford A SA
Biophysical chemistry 20111203
CD and UV resonance Raman measurements surprisingly find that the charge screening of even 2 M concentrations of NaCl and KCl does not alter the unfolded PPII and 2.5(1)-helix conformations of poly-L-glutamate. These salts appear to be excluded from the region between the side chain charges and the peptide backbone. Furthermore, no direct ion pairing occurs between these salts and the side chain carboxylates. ...[more]
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