Journal
BIOCHEMISTRY
Volume 48, Issue 42, Pages 9969-9979Publisher
AMER CHEMICAL SOC
DOI: 10.1021/bi9009067
Keywords
-
Categories
Funding
- National Institutes of Health [GM40941, GM042569]
Ask authors/readers for more resources
Previous crystallographic studies of the AppA BLUF domain indicated that Trp104 is capable of undertaking alternate conformations depending on the length of the BLUF domain, A BLUF domain containing a C-terminal deletion (AppA1-126) reveals that Trpl 04 is partially solvent exposed while a BLUF domain containing a slightly longer carboxyl terminal region (AppA17-133) shows that Trp104 is deeply buried. This observation has led to a model proposing that Trp 104 moves from a deeply buried position in the dark state to a solvent-exposed position in the light excited state. In this study we investigated whether there is indeed movement of TrpI 04 upon light excitation using a combination of NMR and absorption spectroscopy, steady-state fluorescence, and acrylamide quenching of tryptophan fluorescence. Our results indicate that AppA17-133 and AppA1-126 contain Trp 104 in distinct alternate conformations in solution and that light absorption by the flavin causes partial movement/uncovering of Trp104. However, we conclude that light exposure does not cause dramatic change of Trp104 from Trp-in to Trp-out conformations (or vice versa) upon light absorption. These results do not support a model of Trp 104 movement as a key output signal.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available