Ni-affinity purification and reducing agents

[Per Mygind]

-- Fellow Readers

	My question to the readers is concerning affinity-purification of recombinant
proteins, by use of Ni-NTA columns.
	I've constructed and purified recombinant proteins of different kinds, but
I've run my head against a tedious problem. So far, I've used
beta-mercaptoethanol as a reducing agent, if the fusionprotein in question was
containing cysteine-residues. One drawback by using this reagent, is that it
binds covalently to the residues and thereby manipulating an antigenic property
of the fusionprotein.
	My question is, can you use a reducing agent like DTT or DTE instead of
beta-mercaptoethanol. I've heard that it is not possible with Ni-NTA columns,
have anyone got experience with that ? 
Is it maybe possible to remove beta-mercaptoethanol upon purification ? 

Any comments or suggestions will be greatly appreciated

Regards

          Per Mygind , Medical Microbiology , University of Aarhus , Denmark
******************************************************************************

MY OWN PERSONAL FINGERTOUCH

******************************************************************************