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Protein identification in 2D gel - (Jan/11/2010 )


can someone please help me on this?

if we use IPG strip with pH 4-7 for my isoelectric focusing prior gel electrophoresis (in 2D), what will happen to the protein with pH more than 7? I mean, where will they (protein >7) migrate in 2D gel?

This is becasue, after running my 2D, I have always detected a transcitption regulator, whereby the protein is said to have pH more than 8. and it seems to be in many places in the gel throughout the 2D, and also with different MW...

I m puzzled cos the strip for IEF was pH 4-7, is it possible to isolate a protein of pH more than 7? and why is it scatted around the 2D gel?

I aprreatiate any input and suggestions . Thanking you in advanced


Last edited by jocelyn85ang on Mon Jan 11, 2010 1:54 pm, edited 1 time in total. jocelyn85ang

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proteins with pI higher than 7 or lower than 4 should migrate to the respective electrode.

you may be detecting fragments of the protein (they would not have to have the same pI as the whole protein).

or, you may not be focusing long enough for migration to be completed (but i think fragments and aggregates is more likely).