Questions about a SDS-PAGE result - (Mar/20/2006 )
I know that there should be disulfide bond between the polypeptides of protein.
But I can't analyse how the polypeptides link so that the result is like this.
Please help me.
OK, I'm not really used with native gels.
In SDS gels, proteins migrate independently of their charges.
The migration depends only on their size.
Then, if your protein is constituted of 2 subunits of 31 and 67, you should see two bands under reducing conditions, and one band migrating higher (31+67=98) in non reducing conditions.
in the absence of SDS, the migration depends also on the charge of the proteins and not only on their size.
looks like 2 different proteins being analyzed. the sds-page sample is a heterodimer. the native page sample is a homodimer. keep in mind, however, that native page also exhibits a charge separation component.
But I can't analyse how the polypeptides link so that the result is like this.
Please help me.
i guess,there are -s-s- bridge between subunits and bridges among single polypeptide chain
that ,on the native page,with the condition of reducing agent,bridge among single polypeptide chain was destoryed,but without the help of sds, the reducing agent can not reach the bridge between subunits,so,there is still one band but not same place!
Well it's been a few months now since you posted this question.
Since I wasn't part of the forum when you originally asked, I wasn't able to suggest that your question and attachment are likely copied right off a lab exam or quiz.
I would suggest to the forum that we do not condone giving answers out to those who are trying to bypass the system so-to-speak, and who really should be trying to work it out themselves or in group discussion with their colleagues in class.
We really don't benefit anyone in this situation except to get them throught the course without learning anything.
If I'm wrong I apologize, but I'd probably bet the farm I'm right.