Help me on non-denaturing gel or glycerol gradient to measure MW

[Matt Parker]

Li Lu (llu at umabnet.ab.umd.edu) writes:
> Hi, there.
> I wonder if any of you can help me to provide a simple method to tell the 
> difference of MW of different multimer or monomer by either non-denature 
> gel or glycerol gradient. I used invitro translation to make enzyme 
> proteins. Some of my mutant enzyme are inactive. It is known that the 
> enzyme is active when it is a tetramer. I gess some of my mutants (done 
> by site-directed mutagenesis) are monomers. 	Questions:1) what is the 
> best way to tell that the inactive mutants are monomer or tetramer? What 
> is the protocol of the best way. My protein subunit MW is 20Kd. Thanks in 
> advance. Please send your answer to this group or lilu at umabnet.ab.umd.edu

	Try gel filtration (size exclusion) chromatography.