Enjoying the paper, by the way.

I was trying to understand why the fluorescence values with crowder don't show the same changes at the melting points as all of your other data. This appears to be your explanation, but I was wondering about your thoughts as to why there does appear to be a change at 300 mg/ml but not at lower concentrations? Does that observation strengthen or weaken your hypothesis in this paragraph? Do the data possibly point to a different and interesting effect of crowding (e.g. the effect of crowding on ANS binding to the protein)?

It looks like similar things are happening in figures 3 and 4--low concentrations = no fluorescence, high concentrations = fluorescence transition. This clearly isn't central to your article. It just piqued my curiosity trying to figure out what is going on.