Conformational states and fluctuations in endothelial nitric oxide synthase under calmodulin regulation.

ABSTRACT: Mechanisms that regulate nitric oxide synthase enzymes (NOS) are of interest in biology and medicine. Although NOS catalysis relies on domain motions and is activated by calmodulin (CaM) binding, the relationships are unclear. We used single-molecule fluorescence resonance energy transfer (FRET) spectroscopy to elucidate the conformational states distribution and associated conformational fluctuation dynamics of the two NOS electron transfer domains in an FRET dye-labeled endothelial NOS reductase domain (eNOSr) and to understand how CaM affects the dynamics to regulate catalysis by shaping the spatial and temporal conformational behaviors of eNOSr. In addition, we developed and applied a new imaging approach capable of recording three-dimensional FRET efficiency versus time images to char

SUBMITTER: He Y 

PROVIDER: S-EPMC8715171 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature