Protein Crystallization Hits

What a pleasant surprise I had the other week: while sifting through the literature, searching for crystallization cocktails I found a paper that mentioned the Emerald BioSystems Compact Junior plates (available here)

The authors say in the Methods section under "Crystallization...": " Crystals were grown in sitting drops by vapor diffusion using 96-well plates (Emerald BioSystems plate type EBS-XJR)." Thanks for that explicit note! While the crystallization plate can make a substantial  difference (see blog post Crystallization Game Changer Try a Different Plate ) I don't know if is a key to successfully reproducing the crystallization of the Beta Toxin from Staphylococcus aureus. However, the Compact Junior plates are made out of Polypropylene, a plastic material that is very hydrophobic (holds the drops in a nice round shape) and has a very low water permeability and interesting optical properties. This is different from most other protein crystallization plates that are made out of Polystyrene with different material properties.

Related to this topic: while discussing ligand binding assays this week here at Emerald I learned that certain biochemical assays are indeed optimized for plate materials with the notion that some plates may be 'stickier' than others for a particular ligand. Can substantial amounts of hydrophobic ligands diffuse into the plastic and 'disappear' from the crystallization drop? This makes me wonder if co-crystallization experiments in sitting-drop setups that do not yield ligand-bound structures should be troubleshot by changing the plate material, or maybe by switching to conventional hanging drop using glass cover slides. Sounds like a sensible thing to do - is anybody doing this?

Are there any studies or anecdotes in the scientific literature that show a correlation of plate material with ligand/protein co-crystallizations

Let me know if you see any.

Thanks!

Peter