Re: Hydrophobicity of residues

Peter Slickers (slickers@imb-jena.de)
Thu, 1 Feb 1996 15:15:39 +0100 (MET)

Jens wrote:
>
> Here the question is, at which pH do I measure the hydrophobic
> effect.
>
> pH 7 (neutral), acidic or basic environment, ??
>
> If Asparagine or Aspartic acid is more hydrophil should be
> strongly related with the pH. pH also is important for all
> other amino acids, but for aspartate/asparagine and
> glutamate/glutamine it should have the biggest effect.
>
I would like to formalute the same question but in an other
way:

The pK value for dissociation of the C(gamma) carboxyl group
of aspartic acid is 4.4. So there are two different
molecules, aspartic acid (protonated) and aspartate (deprotonated).
The question is, whether aspartic acid or aspartate is more hydrophobic.

Peter

---
Peter Slickers                                  slickers@imb-jena.de
Institut fuer Molekulare Biotechnologie
Beutenbergstrasse 11, Jena                      Tel.: +49-3641-65-6202
Postfach 10 08 13, D-07708 Jena, Germany        Fax:  +49-3641-65-6210