Journal
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
Volume 114, Issue 32, Pages 8562-8567Publisher
NATL ACAD SCIENCES
DOI: 10.1073/pnas.1704391114
Keywords
cAMP; BLUF domain; optogenetics; photoactivation; allostery
Categories
Funding
- Ministry of Education, Culture, Sports, Science and Technology (MEXT)
- Japan Society for the Promotion of Science KAKENHI [JP15H01646, JP16K07326]
- OpenEye Scientific Software
- Grants-in-Aid for Scientific Research [17K15076, 15K21719, 26105001, 16K07326] Funding Source: KAKEN
Ask authors/readers for more resources
The photoactivated adenylate cyclase (PAC) from the photosynthetic cyanobacterium Oscillatoria acuminata (OaPAC) detects light through a flavin chromophore within the N-terminal BLUF domain. BLUF domains have been found in a number of different light-activated proteins, but with different relative orientations. The two BLUF domains of OaPAC are found in close contact with each other, forming a coiled coil at their interface. Crystallization does not impede the activity switching of the enzyme, but flash cooling the crystals to cryogenic temperatures prevents the signature spectral changes that occur on photoactivation/deactivation. High-resolution crystallographic analysis of OaPAC in the fully activated state has been achieved by cryocooling the crystals immediately after light exposure. Comparison of the isomorphous light-and dark-state structures shows that the active site undergoes minimal changes, yet enzyme activity may increase up to 50-fold, depending on conditions. The OaPAC models will assist the development of simple, direct means to raise the cyclic AMP levels of living cells by light, and other tools for optogenetics.
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