Please help me interpret my protein chemical-denaturation graphs
Nov5-13, 02:25 PM
I'm working with proteins at IISc (Bangalore).
I'm characterising a 226-residue long protein of an unknown fold.
I'm trying to use CD spectroscopy to calculate the ΔG for protein unfolding.
I have used both GuHCl (0M - 3M) and Urea (0M - 4M) chemical gradients.
Here are the graphs: http://oi41.tinypic.com/2rtpk.jpg
Please note that I drew the red lines on MS paint. No curve-fitting here.
Ideally, I should get a nice, smooth sigmoidal curve.
However, in both cases, I'm getting an initial 'dip' in CD values.
This would indicate that the protein is folding BETTER under slight denaturing conditions.
These results are reproducible. I've run 3 replicates for each graph.
Have you seen chemical denaturation curves like these before?
If so, how do you interpret such data? Please post links.
-Protein is pretty soluble (purified to 5-10 mg/ml).
-Shows alpha-beta CD spectrum (190-250 nm range).
-It's Tm is 45C (this graph is a smooth sigmoid).
Thanks a lot.
|Register to reply|
|Denaturation and Peptide Bonds||Biology, Chemistry & Other Homework||2|
|Interpret Voltage-time graphs to relate the ouput voltage of a piezoelectric crystal||Electrical Engineering||7|
|how to interpret integrals of graphs||Calculus & Beyond Homework||3|
|Protein - Protein DOCKING ....||Computing & Technology||0|
|Protein of life, protein of death||Biology||3|