Protein expression problem - coexpression? (Jun/02/2006 )
I am working on two genes that are translationally coupled. when I expressed them individually in pET 21, Gene 2 is coming in pellet and sup also but after elution with 50 and 250mM imidozole, a very faint band I am getting the size of this protein is 20KDa. But Gent 1 which is more important, I am not getting expression of this protein. The size is 31 KDa. This protein is not coming in pellet and sup also. I want to ask what may be reason of this? I mean when everything is there then why a protein expresses and the other not?
My boss suggested to use Duet vector to solve this problem but I suspect on this coz the protein which is not coming individually, will it come in duet vector? I am gonna use this vector for the first time, If anybody has used this before plz let me know the important things.
We lack knowledge in molecular biology, so we dont really know why one Pr is expressed and the other not you can guess many thing that cozes that problem and you cannot be sure which one is currect until you try it your self.