Well, I am not a structural biologist, but at one point many years ago I was reasonably well-read on applied GFP biochemistry. I think the reason for the long maturation time could either be (a) slower folding of the expressed protein to the correct beta barrel structure, which seems unlikely, or (b) slow maturation of the chromophore, which seems far more likely. The chromophore maturation is nicely explained by the page you linked to and consists of three steps: (i) "torsional rearrangement", (ii) a cross-chain chemical reaction to form a ring and further stabilize the folded structure, and (iii) reaction of the ring with molecular oxygen to form the extended conjugation required for fluorescence. The "superfolder" GFP variant (sfGFP in your table) seems to accelerate steps 1 and 2. Don't know why esmGFP is slow...my guess is either steps (i) or (ii) are slower, but although I think it's less likely it would be really cool if it were step (iii). (Accidentally creating a protein less permeable to dissolved oxygen gas would be sweet.) Also I found this paper on the folding mechanism of GFP pretty good https://www.sciencedirect.com/science/article/abs/pii/S0022283607010509
Great post as always! Keep up the good work.
:3
Well, I am not a structural biologist, but at one point many years ago I was reasonably well-read on applied GFP biochemistry. I think the reason for the long maturation time could either be (a) slower folding of the expressed protein to the correct beta barrel structure, which seems unlikely, or (b) slow maturation of the chromophore, which seems far more likely. The chromophore maturation is nicely explained by the page you linked to and consists of three steps: (i) "torsional rearrangement", (ii) a cross-chain chemical reaction to form a ring and further stabilize the folded structure, and (iii) reaction of the ring with molecular oxygen to form the extended conjugation required for fluorescence. The "superfolder" GFP variant (sfGFP in your table) seems to accelerate steps 1 and 2. Don't know why esmGFP is slow...my guess is either steps (i) or (ii) are slower, but although I think it's less likely it would be really cool if it were step (iii). (Accidentally creating a protein less permeable to dissolved oxygen gas would be sweet.) Also I found this paper on the folding mechanism of GFP pretty good https://www.sciencedirect.com/science/article/abs/pii/S0022283607010509
Where are you getting the art?