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<DIV dir=ltr align=left><FONT face=Arial color=#0000ff size=2><SPAN
class=878221716-04022009>Mitra,</SPAN></FONT></DIV>
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class=878221716-04022009>My recollection is that IHP does cause a slight
compaction of the structure, but I agree with Arthur that 1.08 sounds a bit low.
I'm wondering whether that might be because you are not using an accurate vbar
value. I wasn't doing AUC back in the dark ages when I worked on hemoglobin, but
I vaguely recall that the additivity rule for vbar may not work well for heme +
globin. I think you will find the experimental vbar in hemoglobin AUC
papers by Stuart J. Edelstein (? '60s-'70s).</SPAN></FONT></DIV>
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<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=878221716-04022009>John</SPAN></FONT></DIV>
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<FONT face=Tahoma size=2><B>From:</B> rasmb-bounces@rasmb.bbri.org
[mailto:rasmb-bounces@rasmb.bbri.org] <B>On Behalf Of </B>Arthur
Rowe<BR><B>Sent:</B> Wednesday, February 04, 2009 6:45 AM<BR><B>To:</B>
mitrana@mail.utexas.edu; rasmb@server1.bbri.org<BR><B>Subject:</B> Re: [RASMB]
Hb tetramer<BR></FONT><BR></DIV>
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<BLOCKQUOTE>Hi Mitra<BR><BR>An f/f0 value of 1.08 (±?) is low-ish, but within
the ball park range for 'globular' proteins. I don't imagine that 2 mM
Inositol would affect the (properly and fully corrected) s value.
<BR><BR>Regards<BR><BR>Arthur<BR><BR></BLOCKQUOTE><BR>
<BLOCKQUOTE><TT>Hello All<BR>Two questions, related ones -<BR><BR>1. Is a
S20,w value of 5.01 too high for a DEOXY Hb tetramer of 67180 <BR>Da MW?
This gives a f/f0 of around 1.08. Just a reminder that deoxy Hb
<BR>tetramer does not dissociate to a dimer much (dissociation constant
~ <BR>10^-11 M).<BR><BR>2. can such an anomaly occur due to Hb
interactions with the <BR>components of the buffer - in this case 2 mM
of Inositol <BR>hexakisphosphate (IHP)?<BR><BR>Glad to hear any comments
and/or references to
papers.<BR><BR>Mitra<BR>_______________________________________________<BR>RASMB
mailing
list<BR>RASMB@rasmb.bbri.org<BR>http://rasmb.bbri.org/mailman/listinfo/rasmb<BR></TT></BLOCKQUOTE><TT><BR></TT><BR>
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