Maybe the "transmembrane usage ratio" is only useful for
measuring the lipophilicity of amino acids and then only if calculated
using only the parts of transmembrane helices that are predicted to be in
contact with the fatty part of the membrane.
Lipophilicity is probably close enough to hydrophobicity for most
purposes but I would also say the lipid membrane must present a
different environment to an amino acid side-chain than the hydrophobic
core of a protein.
-Will
____________________________________________________________
Will Pitt Tel: 44-171-5806851
Crystallography Department, Fax: 44-171-5806803
Birkbeck College, w.pitt@mail.cryst.bbk.ac.uk
Malet Street, http://www.cryst.bbk.ac.uk/~ubcg08l/
London
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