Database searching on % amino acid composition

[adavies at netcom.com]

Is there a compilation of protein sequence data which may be searched on 
the basis of percentage amino acid composition?  I realise that such data 
is tricky to rely on, but I'd be interested in giving it a try....

Any suggestions for approaches to this problem gratefully received!

Anthony.

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Anthony Davies                        Palo Alto Institute of Molecular Medicine
adavies at netcom.com                    2462 Wyandotte Street
Tel: 415-694 4996                     Mountain View
Fax: 415-694 7717                     CA 94043
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