Structure-function relationships of EcDOS, a heme-regulated phosphodiesterase from Escherichia coli
Yukie Sasakura1, Tokiko Yoshimura-Suzuki, Hirofumi Kurokawa
1Bio-Medical Center, R and D Division, Nanotechnology Product Business Group, Hitachi High-Technologies Corporation, Hitachinaka-shi, Ibaraki-ken 312-8504, Japan. sasakura-yukie@naka.hitachi-hitec.com
Abstract:
Recent studies have revealed a new class of heme enzymes, the heme-based sensors, which are able to turn on or off cellular signal transduction pathways in response to environmental changes. One of these enzymes is the heme-regulated phosphodiesterase from Escherichia coli (EcDOS). This protein is composed of an N-terminal heme-containing PAS domain and a C-terminal functional domain. PAS is an acronym formed from the names of the Drosophila period clock protein (PER), vertebrate aryl hydrocarbon receptor nuclear translocator (ARNT), and Drosophila single-minded protein (SIM). The heme cofactor in its PAS domain can act as a sensor of the cellular redox state that regulates the adenosine 3',5'-cyclic monophosphate (cAMP) phosphodiesterase activity. The crystal structures of its heme-containing PAS domain have helped clarify how the heme redox-dependent structural changes initiate intramolecular signal transduction. Here, we review recent findings on the structure-function relationships of EcDOS.
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