Premium
Biochemical characterization of the major adenylyl cyclase, Cya1, in the cyanobacterium Synechocystis sp. PCC 6803
Author(s) -
Masuda Shinji,
Ono Taka-aki
Publication year - 2004
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/j.febslet.2004.09.086
Subject(s) - adenylyl cyclase , blue light , chemistry , biochemistry , cyanobacteria , cyclase , synechocystis , signal transduction , biophysics , bacteria , biology , enzyme , gene , physics , optics , mutant , genetics
We report herein the biochemical properties of an adenylyl cyclase, Cya1, from the cyanobacterium Synechocystis sp. PCC 6803. Heterologously expressed Cya1 catalyzed cyclic AMP formation with a K m for ATP of approximately 2.2 μM at pH 7.5. Although cellular Cya1 activity is increased by blue light illumination [Terauchi and Ohmori, Mol. Microbiol. 52 (2004) 303], purified Cya1 did not contain any chromophores, and the activity was light‐insensitive. This suggests that an unknown blue light‐responsive factor interacts with the N‐terminal regulatory domain of Cya1 to control its adenylyl cyclase activity. Finally, our results show that the sensor of blue light using FAD (BLUF) protein, Slr1694, does not appear to be involved in the regulation of Cya1‐mediated cAMP signal transduction in this bacterium.