Molecular architecture of mammalian nitric oxide synthases.

ABSTRACT: NOSs are homodimeric multidomain enzymes responsible for producing NO. In mammals, NO acts as an intercellular messenger in a variety of signaling reactions, as well as a cytotoxin in the innate immune response. Mammals possess three NOS isoforms--inducible, endothelial, and neuronal NOS--that are composed of an N-terminal oxidase domain and a C-terminal reductase domain. Calmodulin (CaM) activates NO synthesis by binding to the helical region connecting these two domains. Although crystal structures of isolated domains have been reported, no structure is available for full-length NOS. We used high-throughput single-particle EM to obtain the structures and higher-order domain organization of all three NOS holoenzymes. The structures of inducible, endothelial, and neuronal NOS with and with

SUBMITTER: Campbell MG 

PROVIDER: S-EPMC4156747 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature