Green Flourescent Protein: A Computational Study of Hula-Twisting, GFPuv Thermostability and the Role of Arginine96 in Chromophore Formation
Green fluorescent protein (GFP) has revolutionized in vivo cellular and molecular labeling. Three features of GFP that could potentially affect the engineering of better GFPs have been investigated by computational methods.
1. Loss of fluorescence has been documented in GFP and this probably occurs through fast internal conversion. The volume conserving hula twisting HT which was thought to be the mechanism of fast internal conversion does not explain radiationless decay since the φ-one bond flip OBF requires the same volume as the concerted HT.
2. GFPuv is a thermostable mutant that is 45 times more fluorescent at ambient temperatures than the wild-type GFP. The reduced distance between the amide N of Gly67 and the carbonyl C of Ser65, as well as the reduced distance between Arg96 and the carbonyl O of Tyr66 are structural features possibly contributing to the improved thermostability of GFPuv.
3. Arg96 is conserved in almost all GFP mutants and is suspected to play a critical role in one or more of the chromophore forming steps. Our data shows Arg96 is
closer to the carbonyl O of Ser65 than to the corresponding carbonyl of Tyr66.
Baffour-Awuah, Nana Yaa A., "Green Flourescent Protein: A Computational Study of Hula-Twisting, GFPuv Thermostability and the Role of Arginine96 in Chromophore Formation" (2006). Chemistry Honors Papers. 4.
The views expressed in this paper are solely those of the author.