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<DIV><FONT face=Arial size=2>Dear Colleauges ,Tina, Tom
(Laue),</FONT></DIV>
<DIV><FONT face=Arial size=2>I agree absolutly to the here copied
part of the mail of Tom( 9 Jan 2010 17:12)</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV>>>Be aware, too, that solvent density matching using <BR>other
solvent components (e.g. salts, sugars) may result in a <BR>significant shift in
the protein's vbar if there is preferential <BR>solvation, leading to
inaccuracies in interpretation. Depending on what <BR>you use to match density,
preferential solvation may result in <BR>substantial (5 - 10% error) in vbar.
Since there is a 3-fold lever arm <BR>that results in a 3% error in M for every
1% error in vbar, there may be <BR>a 15-30% error in M if the preferential
solvation is not accounted for.<<<BR></DIV>
<DIV><FONT face=Arial size=2>At the BBA 1464 (2000) 199 -206 Ariel
Lustig, paper, we calculated (better to say
Prof. Andreas Engel</FONT></DIV>
<DIV><FONT face=Arial size=2>of the Basel Biozentrum
calculated it) that The error with our methode
is + / - 15% for the Mw, (just </FONT></DIV>
<DIV><FONT face=Arial size=2>mentioned on the first page, the
Abstract)</FONT></DIV>
<DIV><FONT face=Arial size=2>Our opinion is, that the pourpose to
determine how nany monomers contains such a micelle , even
15%</FONT></DIV>
<DIV><FONT face=Arial size=2>is a big help for biological
systemes....yours...ariel</FONT></DIV>
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