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<DIV><!-- Converted from text/plain format --><FONT face=Arial
size=2>RASMB,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thanks to Holger Strauss and his lab, we finally
have density and viscosity data for DTT, and I have now calculated the
polynomial coefficients needed to put those data into the SEDNTERP database. If
you need to enter those manually, I've put those coefficients at the end of
this message, but you shouldn't need to do that. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>These are the first new user-contributed data for
many, many, years, and perhaps they will inspire one of you to finally
measure other things many people want (HEPES, PIPES, trehalose, sorbitol, Tween,
...)</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I am also now releasing version 1.09 of SEDNTERP,
which will automatically incorporate the new DTT data. I actually hadn't planned
to ever release new updates to version 1 because Tom Laue and David Hayes
have been working on version 2 for some time, but I recently found a small
problem that might lead to incorrect results (not actually a bug, but more
an issue of semantics). Let me explain:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>When you press the 'Print Summary Report' button
from the Sample Composition form that printout has always included the "mean
residue weight", along with many other things. That value has always been
literally what it says, <EM>i.e.</EM> the molecular weight divided by the total
number of amino acids. However, within the circular dichroism community a
quantity that is often called "mean residue weight" is actually the
molecular weight <U>per peptide bond</U>, i.e. MW divided by (total amino acids
- 1). To further add to the confusion, some people in the CD field use the first
definition, some the second. If you are working with a protein of 100 amino
acids or more the difference between the two definitions will be 1% or less and
thus less than the experimental error, so one can easily just ignore this
distinction. However if you are working with a small peptide these two numbers
will be significantly different, and using the wrong one would affect the
fraction alpha helix <EM>etc.</EM> that one computes. Therefore version 1.09 now
prints <U>both</U> numbers (per residue and per peptide bond), and you can use
whichever makes sense for your purposes.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><SPAN class=401125616-04092006><FONT face=Arial size=2>As many of you are
aware, there has been a problem arising under Windows XP that causes a crash
after an "illegal function call" message when you try to bring up the buffer
composition dialog box. This is a Microsoft compatibility issue that I can't
directly fix---Windows XP actually runs the code in the wrong order!
However for some reason (dumb luck?) I have not yet seen this crash with
the new version. If you are still having this problem, try using the File...New
command before you do anything else, which seemed to help for version
1.08.</FONT></SPAN></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>The easiest way to update SEDNTERP, and
simultaneously add the new DTT data, is to download a self-extracting updating
file sdnupdat.exe, either from </FONT><A
href="http://www.jphilo.mailway.com/download.htm"><FONT face=Arial
size=2>http://www.jphilo.mailway.com/download.htm</FONT></A><FONT face=Arial
size=2> or the RASMB archive</FONT><SPAN class=401125616-04092006><FONT
face=Arial size=2>, </FONT><A
href="http://www.rasmb.bbri.org/rasmb/windows/sednterp-philo/"><U><FONT
color=#0000ff><FONT face=Arial
size=2>http://www.rasmb.bbri.org/rasmb/windows/sednterp-philo/</FONT></U></FONT></A></SPAN><FONT
face=Arial size=2>. Alternatively you can download the full version
(sdtr0601.exe) and install it into the existing folder. The first time you run
the new version it will detect the database update, <SPAN
class=401125616-04092006>bring</SPAN> up a dialog box saying it is updating to
revision level 1.1, and then will add the new DTT data.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Best regards to all,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>John</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>----------------------------------</FONT></DIV>
<DIV><FONT face=Arial size=2>Database entries for DTT density:</FONT></DIV>
<DIV><FONT face=Arial size=2>a = 0.9982</FONT></DIV>
<DIV><FONT face=Arial size=2>b = 0</FONT></DIV>
<DIV><FONT face=Arial size=2>c = 4.15428</FONT></DIV>
<DIV><FONT face=Arial size=2>d = 0</FONT></DIV>
<DIV><FONT face=Arial size=2>e = 0</FONT></DIV>
<DIV><FONT face=Arial size=2>f = 0</FONT></DIV>
<DIV><FONT face=Arial size=2>Cmax = 0.13</FONT></DIV>
<DIV><FONT face=Arial size=2>Max error = 0.5</FONT></DIV>
<DIV><FONT face=Arial size=2>Source = Holger Strauss</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV>
<DIV><FONT face=Arial size=2>Database entries for DTT viscosity:</FONT></DIV>
<DIV><FONT face=Arial size=2>a = 1.0000</FONT></DIV>
<DIV><FONT face=Arial size=2>b = 0</FONT></DIV>
<DIV><FONT face=Arial size=2>c = 28.824</FONT></DIV>
<DIV><FONT face=Arial size=2>d = 0</FONT></DIV>
<DIV><FONT face=Arial size=2>e = 0</FONT></DIV>
<DIV><FONT face=Arial size=2>Cmax = 0.13</FONT></DIV>
<DIV><FONT face=Arial size=2>Max error = 1.5</FONT></DIV>
<DIV><FONT face=Arial size=2>Source = Holger Strauss</FONT></DIV></DIV>
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