Not a contradiction at all :) If the protein supply is adequate - this is a perfectly good approach to explore. I simply forgot to mention it.
I've also not mentioned engineering the protein's surface (works really well for us because we have secret ways to do this, learned from ancient and mysterious Shaolin monks) or derivatizing the protein with chemicals - these are excellent but require more work on the researcher's behalf. If the methods that people suggested so far do not result in success (which is unfortunate but not uncommon) - you can always change the protein itself! Good luck :) Artem > Hi Jobi > > Sounds like you need to explore your protein vs PEG concentration, and my > guess (directly contradicting Artem's) is that chances are you need to > pump > [protein] way up and drop [PEG] way down. > > Like in [protein]=>30-40mg/ml, [PEG]<=2-4%. Often people don't go into > that > range when setting up optimizations, because the original condition was, > say, 25% PEG. But looking at the solubility curve, this is the regime > where > few nuclei form and then have lots of protein to grow with. > > phx.