Re: late Re: Hydrophobicity of residues

Christoph Weber (
Tue, 25 Jun 1996 10:57:47 -0700

Hi all,

I think that the concept of "transmembrane usage ratio" is biased. The reason:
Some transmembrane protein domains specifically serve the purpose to place
select polar amino acid sidechains into this environment, for example in
transmembrane channels.
Witness the values for the Glu/Gln and Asp/Asn pairs which make the charged
sidechains appear less hydrophobic than their neutral counterparts. I would
argue that those are in transmembrane segments for a very specific function and
thus distort a classification that should reflect physico-chemical properties

I find the concept interesting, though, if only to provoke some thought...


|  Christoph Weber                  Sen. Research Associate
|  Dept.of Molecular Biology, MB2   619-554-7283 or -8754 (phone)
|  The Scripps Research Institute   619-554-3757 (FAX)
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