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<DIV><SPAN class=069463217-11032003><FONT face=Arial color=#0000ff size=2>Chris
et al.,</FONT></SPAN></DIV>
<DIV><SPAN class=069463217-11032003><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=069463217-11032003><FONT face=Arial color=#0000ff size=2>I have
not used the Segal software and thus can't comment specifically on that, but I
think the underlying problem here is probably your data itself. You have
a very large baseline offset of ~0.11 OD, and under such circumstances
the apparent molecular weight will be quite sensitive to the
offset value (and very highly correlated to it). I suspect the differences
between the Origin and Segal results have mostly to do with how the baseline
offsets are handled. That large baseline offset also suggests there may have
been something wrong with the sample---it actually looks to me like it may
not really be a constant offset but rather that you have some low mass
contaminant (or even some proteolysis).</FONT></SPAN></DIV>
<DIV><SPAN class=069463217-11032003><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=069463217-11032003><FONT face=Arial color=#0000ff
size=2>Second, you haven't given any confidence limits for these numbers and
thus haven't addressed the question of whether the difference in mass results
from the different programs is even statistically significant. The Origin
software, for example, says your 'Edit 1' result of 67 kDa has a 95% confidence
interval of 62 to 71 kDa, and thus it is certainly not different from the 65-66
kDa Origin Edit 2 or Edit 3 results. </FONT></SPAN><SPAN
class=069463217-11032003><FONT face=Arial color=#0000ff size=2>This 67
kDa value probably is a real difference from the 59 kDa Segal result
(which as I said above probably relates to baseline offsets), but one can't
even properly ask that question unless there is a confidence limit on the Segal
result.</FONT></SPAN></DIV>
<DIV><SPAN class=069463217-11032003><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=069463217-11032003><FONT face=Arial color=#0000ff size=2>Third,
regarding your data again (but not the software issue), as Ariel Lustig noticed
too, you were using quite a long solution column (5 mm). Are you sure
that sample was fully at equilibrium within the 24 hr you apparently
gave it? That 24 hr for a 5 mm column is equivalent to <9 hr for the usual 3
mm column height, which definitely seems too short.</FONT></SPAN></DIV>
<DIV><SPAN class=069463217-11032003><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=069463217-11032003><FONT face=Arial color=#0000ff
size=2>Finally, I would urge some caution with trimming your data. Your message
implies that your criterion for data selection is to get the lowest variance,
but that is only a legitimate criterion if you are fitting to the correct model.
For example, it is easy to make a sample that contains irreversible aggregates
fit nicely as a single species by simply trimming away the regions at the
base where the aggregates are concentrated (and by rigorously applying your
lower variance criterion that is exactly what will happen). Especially when you
have a limited range of concentrations, getting your data to fit a given model
can quickly become a self-fulfilling prophecy if you just trim away the points
that don't fit!</FONT></SPAN></DIV>
<DIV><SPAN class=069463217-11032003><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=069463217-11032003><FONT face=Arial color=#0000ff
size=2>Knowing what is 'good' or 'bad' data in equilibrium experiments is
unfortunately a bit of an art, but in my view should primarily be guided by your
knowledge of the hardware and optical system. Thus one easy,
unbiased, criterion for 'bad' data is that the absorbance is too high
(outside the region of linearity). It is also true that the absorbance data tend
to be bad near the base of the cell, apparently due to reflections, and
that bad region should be the same for all samples in that type of cell (since
it is a matter of cell geometry). </FONT></SPAN></DIV>
<DIV><SPAN class=069463217-11032003><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=069463217-11032003><FONT face=Arial color=#0000ff size=2>John
Philo</FONT></SPAN></DIV>
<DIV><SPAN class=069463217-11032003><FONT face=Arial color=#0000ff
size=2>Alliance Protein Laboratories</FONT></SPAN></DIV>
<BLOCKQUOTE dir=ltr style="MARGIN-RIGHT: 0px">
<DIV></DIV>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left><FONT
face=Tahoma size=2>-----Original Message-----<BR><B>From:</B>
rasmb-admin@rasmb-email.bbri.org [mailto:rasmb-admin@rasmb-email.bbri.org]
<B>On Behalf Of </B>Chin, Christopher<BR><B>Sent:</B> Wednesday, March 05,
2003 1:51 PM<BR><B>To:</B> ArielLustig Lustig (E-mail); Rasmb
(E-mail)<BR><B>Subject:</B> [RASMB] Compare MW obtained from Segal vs. MW
obtained from Beckman Origi n<BR><BR></FONT></DIV>
<DIV><FONT face=Arial size=2>
<P class=MsoNormal>Dear Ariel,</P>
<P class=MsoNormal> <o:p></o:p></P>
<P class=MsoNormal>I am a big fan of your Segal program because of the
user-friendly feature.<SPAN style="mso-spacerun: yes"> </SPAN>The
dynamic fitting pictures that change in front of your eyes for you to select
the best fitting radius region to use is a great time saver in data
analysis.<SPAN style="mso-spacerun: yes"> </SPAN>In the Beckman Origin
program, editing equilibrium curve in the dark by guessing is no fun.<SPAN
style="mso-spacerun: yes"> </SPAN>I have to edit several radius regions,
one by one, in order to obtain the best variance value so I can have confident
in the result. </P>
<P class=MsoNormal> <o:p></o:p></P>
<P class=MsoNormal>I do a lot of calculation for Ka at various GuHCl
concentrations in order to estimate the free energy of subunit dissociation
using Beckman’s origin program.<SPAN style="mso-spacerun: yes"> </SPAN>I
constantly worry that I am not getting the best apparent molecular weight to
use for Ka calculation.<SPAN style="mso-spacerun: yes"> </SPAN>Lately I
have combined Segal and Origin program, meaning that I apply Segal program to
get what I think is the best fitting radius region, I then reapply this same
radius region to edit the subset from the Beckman Origin program (since your
program can not be used to calculate Ka), thinking that with this combine
approach I can surely get the best reliable MW to use for an accurate Ka. </P>
<P class=MsoNormal> <o:p></o:p></P>
<P class=MsoNormal>However, to my surprise, I do not get the same molecular
weight even if I use exactly the same radius boundary values.<SPAN
style="mso-spacerun: yes"> </SPAN>Of the 4 set of edited subset data I
tested, the discrepancy various from 4 to 14 %.<SPAN
style="mso-spacerun: yes"> </SPAN>Do you know where is this discrepancy
coming from? Is Beckman fitting equation different than the equation you used
for Segal program?<SPAN style="mso-spacerun: yes"> </SPAN>Is 4-14%
discrepancy acceptable?<SPAN style="mso-spacerun: yes"> </SPAN>I think I
can live with 5-6% discrepancy. I am including the raw data 00008.ra1 for
anyone who is interested in looking into this.<SPAN
style="mso-spacerun: yes"> </SPAN>I have not included NONLIN in this
comparison.</P>
<P class=MsoNormal> <o:p></o:p></P>
<P class=MsoNormal><B><SPAN
style="FONT-SIZE: 14pt; mso-bidi-font-size: 12.0pt">Summary: </SPAN></B><SPAN
style="mso-spacerun: yes"> </SPAN>4 set of the edit<B><SPAN
style="FONT-SIZE: 14pt; mso-bidi-font-size: 12.0pt"> </SPAN></B>data from raw
data 00008.ra1</P>
<P class=MsoHeader
style="tab-stops: .5in center 3.0in right 6.0in"> <o:p></o:p></P>
<TABLE
style="BORDER-RIGHT: medium none; BORDER-TOP: medium none; BORDER-LEFT: medium none; BORDER-BOTTOM: medium none; BORDER-COLLAPSE: collapse; mso-border-alt: solid windowtext .5pt; mso-padding-alt: 0in 5.4pt 0in 5.4pt"
cellSpacing=0 cellPadding=0 border=1>
<TBODY>
<TR>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: windowtext 0.5pt solid; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 88.55pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid"
vAlign=top width=118>
<P class=MsoNormal style="TEXT-ALIGN: center" align=center><B><I>Edit
Equilibrium curve<o:p></o:p></I></B></P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: windowtext 0.5pt solid; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 88.55pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt"
vAlign=top width=118>
<P class=MsoNormal style="TEXT-ALIGN: center"
align=center><B><I>Boundary radius region used<o:p></o:p></I></B></P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: windowtext 0.5pt solid; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 88.55pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt"
vAlign=top width=118>
<P class=MsoNormal style="TEXT-ALIGN: center" align=center><B><I>MW
obtained from Origin / variance<o:p></o:p></I></B></P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: windowtext 0.5pt solid; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 1.5in; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt"
vAlign=top width=144>
<P class=MsoNormal style="TEXT-ALIGN: center" align=center><B><I>MW
obtained from Segal / correlation<o:p></o:p></I></B></P>
<P class=MsoNormal style="TEXT-ALIGN: center"
align=center> <B><I><o:p></o:p></I></B></P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: windowtext 0.5pt solid; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 88.6pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt"
vAlign=top width=118>
<H3><SPAN
style="FONT-SIZE: 14pt; mso-bidi-font-size: 12.0pt">Discrepancy@
%<o:p></o:p></SPAN></H3></TD></TR>
<TR>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 88.55pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=118>
<H2>Edit 1</H2></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 88.55pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=118>
<P class=MsoNormal style="TEXT-ALIGN: center"
align=center>6.913-7.148</P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 88.55pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=118>
<P class=MsoNormal style="TEXT-ALIGN: center" align=center>67 KD /
17.1</P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 1.5in; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=144>
<P class=MsoNormal style="TEXT-ALIGN: center" align=center>59 KD /
0.999458</P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 88.6pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=118>
<P class=MsoNormal style="TEXT-ALIGN: center" align=center><I><SPAN
style="FONT-SIZE: 14pt; mso-bidi-font-size: 12.0pt">12<o:p></o:p></SPAN></I></P></TD></TR>
<TR>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 88.55pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=118>
<P class=MsoNormal style="TEXT-ALIGN: center" align=center><B><I>Edit
2<o:p></o:p></I></B></P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 88.55pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=118>
<P class=MsoNormal style="TEXT-ALIGN: center"
align=center>6.942-7.139</P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 88.55pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=118>
<P class=MsoNormal style="TEXT-ALIGN: center" align=center>66KD /
18.3</P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 1.5in; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=144>
<P class=MsoNormal style="TEXT-ALIGN: center" align=center>60 KD /
0.999504</P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 88.6pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=118>
<P class=MsoNormal style="TEXT-ALIGN: center" align=center><I><SPAN
style="FONT-SIZE: 14pt; mso-bidi-font-size: 12.0pt">9<o:p></o:p></SPAN></I></P></TD></TR>
<TR>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 88.55pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=118>
<P class=MsoNormal style="TEXT-ALIGN: center" align=center><B><I>Edit
3<o:p></o:p></I></B></P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 88.55pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=118>
<P class=MsoNormal style="TEXT-ALIGN: center"
align=center>6.920-7.139</P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 88.55pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=118>
<P class=MsoNormal style="TEXT-ALIGN: center" align=center>65 KD /
17.8</P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 1.5in; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=144>
<P class=MsoNormal style="TEXT-ALIGN: center" align=center>56 KD /
0.999322</P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 88.6pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=118>
<P class=MsoNormal style="TEXT-ALIGN: center" align=center><I><SPAN
style="FONT-SIZE: 14pt; mso-bidi-font-size: 12.0pt">14<o:p></o:p></SPAN></I></P></TD></TR>
<TR>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 88.55pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=118>
<P class=MsoNormal style="TEXT-ALIGN: center" align=center><B><I>Edit
4<o:p></o:p></I></B></P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 88.55pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=118>
<P class=MsoNormal style="TEXT-ALIGN: center"
align=center>6.897-7.118</P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 88.55pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=118>
<P class=MsoNormal style="TEXT-ALIGN: center" align=center>56 KD /
13.1</P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 1.5in; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=144>
<P class=MsoNormal style="TEXT-ALIGN: center" align=center>54 KD /
0.999435</P></TD>
<TD
style="BORDER-RIGHT: windowtext 0.5pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: medium none; WIDTH: 88.6pt; PADDING-TOP: 0in; BORDER-BOTTOM: windowtext 0.5pt solid; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt"
vAlign=top width=118>
<P class=MsoNormal style="TEXT-ALIGN: center" align=center><I><SPAN
style="FONT-SIZE: 14pt; mso-bidi-font-size: 12.0pt">4<o:p></o:p></SPAN></I></P></TD></TR></TBODY></TABLE>
<P class=MsoNormal>@ (<B><I> MW obtained from Origin<SPAN
style="mso-spacerun: yes"> </SPAN>-<SPAN
style="mso-spacerun: yes"> </SPAN>MW obtained from Segal) / MW obtained
from Origin<SPAN style="mso-spacerun: yes"> </SPAN></I></B></P>
<P class=MsoNormal> <o:p></o:p></P>
<P class=MsoNormal> <o:p></o:p></P>
<P class=MsoNormal> <o:p></o:p></P>
<P class=MsoNormal>With best regards,</P>
<P class=MsoNormal> <o:p></o:p></P>
<P class=MsoNormal>Chris</P>
<P class=MsoNormal> <o:p></o:p></P></FONT></DIV>
<P><FONT face=Arial
size=2>--------------------------------------------------------------------------</FONT>
<BR><FONT face=Arial size=2>Christopher Chin</FONT> <BR><FONT face=Arial
size=2>Manager, XLA-Analytical Ultracentrifugation facility</FONT> <BR><FONT
face=Arial size=2>Sealy Center for Structural Biology</FONT> <BR><FONT
face=Arial size=2>HBC&G, 5.134 MRB.UTMB, Galveston,Tx 77555-1055</FONT>
<BR><FONT face=Arial size=2>cchin@utmb.edu, 409-772-1693, efax
708-585-1920</FONT> <BR><FONT face=Arial
size=2>---------------------------------------------------------------------------</FONT>
</P><BR>
<DIV> </DIV></BLOCKQUOTE></BODY></HTML>