You are correct. See */Protein Sci/* Thurlkill et al. 15 (5): 1214,
http://www.proteinscience.org/cgi/reprint/15/5/1214, which is a recent
effort to codify "typical" pKa values for protein ionizable groups.
Cheers,
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Roger S. Rowlett
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Patrick Loll wrote:
> What value do we expect for the pKa of a protein's C-terminal
> carboxylate? pKa values for free amino acids are quite low (2-3), but
> it seems to me that this may have something to do with the proximity
> of a free amine group; I'd expect a higher value (4-ish?) for the
> peptide's C-terminus.
>
> A quick & lazy search using the term "pka" was stymied by a gazillion
> references to protein kinase A...
>
> Thanks,
> Pat
>
>
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>
> Patrick J. Loll, Ph. D.
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