TCA precipitation

Peter Pediaditakis pxpst2 at vms.cis.pitt.edu
Fri Jan 30 09:55:04 EST 1998


In article <01bd2cfc$c93f6e00$0e3163c3 at f.--j.beal>, "Jane Beal"
<J.D.Beal at btinternet.com> wrote:

> Hi All
> Does anybody know how small, in terms of M.W or AA residues, a peptide has
> to be before it is soluble in TCA or sulphosalycilic acid.  Does solubility
> in these reagents depend on the source of protein.


A lose approximation would be 20 KD.  But the bigest problem with TCA is
that proteins of similar molecular mass may precipitate differently in
TCA.  Thus if you had a mixture of proteins some will come down while
others do not.  Factors influencing TCA precipitation include
Glycosylation(reduces efficiency), Hydrophobicity and others.
I think that the Wessel Fluege method is better and the Phenol Ether
method is better

reference:  Concentration of Dilute Protein for Gel Electrophoresis, Anal.
Biochem., 226, 382-383 (1995)


Also TCA stored for a while can breakdown and form HCl which can hydrolyze
your protein


Peter Pediaditakis

-- 
"Don't you eat that yellow snow
    WAtch out where the Huskies go"

---------------------------------------------------------------------

Let us not forget those marketing boys from SPAM CENTRAL

bestrealtor at marketingmaster.com
info at herbchew.com
clickthru at timefreedom.com
invite at onlinenow.net
zippydj at nevwest.com
Offer at shire.com
empower at empowerlabs.com
dynamarket at vaprnet.com
root at mail.icongrp.com
cashrewards at hotmail.com



More information about the Proteins mailing list