G-protein modification

Wolfgang Schechinger wgschech at med.uni-tuebingen.de
Wed Apr 2 09:21:42 EST 1997

Content-type: text/plain; charset=US-ASCII
Content-transfer-encoding: 7BIT


Lactones are intrinsic esters of molecules carrying a carboxylic 
(-COOH) and a hydroxyl (-OH) function, both are present in mevalonic 

Mevalonic acid is (thought to be) unstable, thus you will have to use 
mevalonolactone. It should be cleaved with no problems by cells (at 
least, renal mesangial cells and SMCs do so, my own experience). You 
should be able to cleave the lacton "manually" by acidification if 
neccessary, if the components of your expression systems don't cleave 
it. Actually, the lacton should be in equlilibrium with the free 
acid, as soon water is present in your system ;-) 

Although this interferes with my statements on the 
stability of the substance unless mevalonolactone is the exact 
product you might get when you leave mevalonic acid for a while alone 
(Just my own thoughts, maybe anyone else knows more about this and 
wants to comment).

Mevalonolactone should do it, since it is used to rescue from 
HMG-CoA-reductase inhibition (HMGCoA-R. produces mevalonic acid!!) by 
Lovastatin or Simvastatin.

Good luck!


> Dear All
> I have a question concerning the lipid modification of G-protein
> gamma subunits. I have sme references where the gamma subunit was
> isoprenylated in an invitro expression system by the addition of
> radiolabelled mevalonolactone I want to be able to use a 'cold' form
> but the only reagent I can see is mevalonic acid lactone is this the
> same stuff?
> Thanks in advance
> Robert
> rw200 at cus.cam.ac.uk
> k
> -- 
---------!all possible disclaimers apply!-----------
Wolfgang Schechinger
University of Tuebingen
email: wgschech at med.uni-tuebingen.de


public PGP key is avilable on request	

More information about the Methods mailing list