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<DIV><SPAN class=726354713-28022008><SPAN class=591374208-03032008><FONT
face=Arial size=2>Dear AUC users,</FONT></SPAN></SPAN></DIV>
<DIV><SPAN class=726354713-28022008><FONT face=Arial size=2><SPAN
class=591374208-03032008>I have a problem in the fitting of some data and I
would like to have your opinion.</SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=726354713-28022008><FONT face=Arial size=2><SPAN
class=591374208-03032008></SPAN></FONT></SPAN> </DIV>
<DIV><SPAN class=726354713-28022008><FONT face=Arial><FONT size=2>I want to
control the sedimentation of<SPAN class=591374208-03032008> </SPAN><SPAN
class=591374208-03032008>a </SPAN>protein in order to define the state of
oligomerization. <SPAN class=591374208-03032008>It is published as forming
an <SPAN class=591374208-03032008> h</SPAN>e<SPAN
class=591374208-03032008>x</SPAN>americ homo oligomer.<SPAN
class=591374208-03032008> </SPAN>From the crystal structure, i</SPAN>t
is a wheel like structure of 160<SPAN
class=591374208-03032008> angstrom</SPAN><SPAN
class=591374208-03032008> </SPAN> in diameter, with a central role of
15<SPAN class=591374208-03032008> </SPAN>angstrom in diameter.<SPAN
class=591374208-03032008> </SPAN><SPAN class=591374208-03032008>The
thickness is 20-40 angstrom. How can I expect it to sediment? How can I improve
my parameters or model in order to improve the
fitting?</SPAN></FONT></FONT></SPAN></DIV>
<DIV><SPAN class=726354713-28022008><FONT face=Arial size=2><SPAN
class=591374208-03032008></SPAN></FONT></SPAN> </DIV>
<DIV><SPAN class=726354713-28022008><FONT face=Arial size=2>The protein is
50KDa <SPAN class=591374208-03032008> but in </SPAN>gel
filtration it cames out as <SPAN class=591374208-03032008> hexamer
(300 KDa)</SPAN>.<SPAN class=591374208-03032008> </SPAN>In my sedimentation
experiment I see <SPAN class=591374208-03032008>one </SPAN>peak
of <SPAN class=591374208-03032008> 6.23S which corresponds to
</SPAN>140KDa. <SPAN class=591374208-03032008><FONT color=#0000ff>Fitting
of the sedimentation data was done with SedFit. </FONT></SPAN><SPAN
class=591374208-03032008>D</SPAN>o you think I can say that it is a trimer? I
would expect it as an <SPAN
class=591374208-03032008>h</SPAN>examer.</FONT></SPAN></DIV>
<DIV><SPAN class=726354713-28022008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=726354713-28022008><FONT face=Arial><FONT size=2>I
hope someo<FONT color=#0000ff><SPAN class=591374208-03032008>ne</SPAN><SPAN
class=591374208-03032008> can</SPAN></FONT> help me<SPAN
class=591374208-03032008><FONT
color=#0000ff>. </FONT></SPAN></FONT></FONT></SPAN></DIV>
<DIV><SPAN class=726354713-28022008><FONT face=Arial><FONT color=#0000ff
size=2><SPAN class=591374208-03032008></SPAN></FONT></FONT></SPAN> </DIV>
<DIV><SPAN class=726354713-28022008><FONT face=Arial size=2>the conditions are
:</FONT></SPAN><SPAN class=726354713-28022008><FONT face=Arial
size=2> </FONT></DIV>
<DIV>
<DIV class=O v:shape="_x0000_s2050">
<DIV
style="mso-line-spacing: '100 50 0'; mso-char-wrap: 1; mso-kinsoku-overflow: 1"><SPAN
style="FONT-SIZE: 58%"><FONT face=Arial size=2>buffer 20mM Tris pH7, 150mM NaCl,
1mM DTT, 5%gly </FONT></SPAN></DIV>
<DIV
style="mso-line-spacing: '100 50 0'; mso-char-wrap: 1; mso-kinsoku-overflow: 1"><SPAN
style="FONT-SIZE: 58%"><FONT face=Arial size=2>Vbar 0.7397 </FONT></SPAN></DIV>
<DIV
style="mso-line-spacing: '100 50 0'; mso-char-wrap: 1; mso-kinsoku-overflow: 1"><SPAN
style="FONT-SIZE: 58%"><FONT face=Arial size=2>Viscosity 1.02530
</FONT></SPAN></DIV>
<DIV
style="mso-line-spacing: '100 50 0'; mso-char-wrap: 1; mso-kinsoku-overflow: 1"><SPAN
style="FONT-SIZE: 58%"><FONT face=Arial size=2>Density 0.01183
</FONT></SPAN></DIV>
<DIV
style="mso-line-spacing: '100 50 0'; mso-char-wrap: 1; mso-kinsoku-overflow: 1"><SPAN
style="FONT-SIZE: 58%"><FONT face=Arial size=2></FONT></SPAN> </DIV>
<DIV
style="mso-line-spacing: '100 50 0'; mso-char-wrap: 1; mso-kinsoku-overflow: 1"><SPAN
style="FONT-SIZE: 58%"><SPAN class=726354713-28022008><FONT face=Arial
size=2>Thanks a lot</FONT></SPAN></SPAN></DIV>
<DIV
style="mso-line-spacing: '100 50 0'; mso-char-wrap: 1; mso-kinsoku-overflow: 1"><SPAN
style="FONT-SIZE: 58%"><SPAN class=726354713-28022008><FONT face=Arial><FONT
size=2>Marina<SPAN
class=591374208-03032008> </SPAN></FONT></FONT></SPAN></SPAN></DIV>
<DIV
style="mso-line-spacing: '100 50 0'; mso-char-wrap: 1; mso-kinsoku-overflow: 1"><SPAN
style="FONT-SIZE: 58%"><SPAN class=726354713-28022008><FONT size=2><SPAN
class=591374208-03032008></SPAN></FONT></SPAN></SPAN> </DIV>
<DIV
style="mso-line-spacing: '100 50 0'; mso-char-wrap: 1; mso-kinsoku-overflow: 1"><SPAN
style="FONT-SIZE: 58%"><SPAN class=726354713-28022008><FONT size=2><SPAN
class=591374208-03032008></SPAN></FONT></SPAN></SPAN> </DIV>
<DIV
style="mso-line-spacing: '100 50 0'; mso-char-wrap: 1; mso-kinsoku-overflow: 1"><SPAN
style="FONT-SIZE: 58%"><SPAN class=726354713-28022008><FONT size=2><SPAN
class=591374208-03032008> </SPAN></FONT></SPAN></SPAN></DIV>
<DIV style="mso-line-spacing: '100 50 0'"><SPAN
style="mso-special-format: lastCR"><FONT face=Arial
size=2></FONT></SPAN></DIV></DIV></SPAN></DIV>
<DIV><FONT face=Arial size=2>MARINA FASOLINI</FONT></DIV>
<DIV><FONT face=Arial size=2>Structural Chemistry </FONT></DIV>
<DIV><FONT face=Arial size=2><A href="http://www.nervianoms.com/">Nerviano
Medical Sciences</A></FONT></DIV>
<DIV><FONT face=Arial size=2>Viale Pasteur 10</FONT></DIV>
<DIV><FONT face=Arial size=2>20014 Nerviano - </FONT><FONT face=Arial
size=2>Milano</FONT></DIV>
<DIV><FONT face=Arial size=2><A
href="mailto:marina.fasolini@nervianoms.com">marina.fasolini@nervianoms.com</A></FONT></DIV>
<DIV><FONT face=Arial size=2>Tel. +390331581462</FONT></DIV>
<DIV><FONT face=Arial size=2>Fax. +390331581360</FONT></DIV>
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