Factor Xa cDNA

[Wolfgang Schechinger]

Peter, 

This issue seems to be quite a drawback.

I'd need a protease that is highly specific and constitutionally
active under cytosolic conditions but has virtually no targets in
unmodified cells. Any ideas what protease would be a good choice?

Wolfgang

> 
> > I imagine he wants to make it in bacteria to use for cleaving GST
> > tags off of fusion proteins.  It very expensive to buy, aty least
> > it used to be..
> 
> I completely forgot about that use.  If that is the case, I would
> say "find another enzyme".  Although factor X can be easily
> activated by Russel's Viper Venom to form factor Xa, one must also
> purify (from rvv) and lyophilize the protein.  Factor Xa is
> autoprotolytic and so this must be done fast.  If your lab is not
> set up for large scale protein purifications, this would be
> difficult.  As for Factor Xa, it has a very poorly defined
> recognition site.  I can give you no less than 15 such sites that
> difer from the fXa thrombin cut site.  
> 
> Peter Pediaditakis

Dr. Wolfgang Schechinger, Pathobiochemistry Dept.      
University of Tuebingen, Germany
email: wolfgang.schechinger at med.uni-tuebingen.de 
wwWait: http://www.medizin.uni-tuebingen.de/~wgschech/start.htm
-----
*unsolicited mail is *NOT* appreciated, usual disclaimers apply 
-----                         


Dr. Wolfgang Schechinger, Pathobiochemistry Dept.      
University of Tuebingen, Germany
email: wolfgang.schechinger at med.uni-tuebingen.de 
wwWait: http://www.medizin.uni-tuebingen.de/~wgschech/start.htm
-----
*unsolicited mail is *NOT* appreciated, usual disclaimers apply 
-----                         
---