Heme domain plasticity Quaternary Structure Controls Ligand Dynamics in Soluble Guanylate Cyclase
نویسندگان
چکیده
Background: NO and CO dynamics are compared in soluble guanylate cyclase and isolated heme domain. Results: CO geminately rebinds to the isolated heme domain β1(190), contrary to entire sGC. Photo-oxidation of β1(190) heme may occur. Conclusion: The isolated heme domain β1(190) has a different reactivity than full-length sGC. Significance: The structural strains between domains in the full-length protein are crucial for its functioning.
منابع مشابه
Quaternary structure controls ligand dynamics in soluble guanylate cyclase.
Soluble guanylate cyclase (sGC) is the mammalian endogenous nitric oxide (NO) receptor. The mechanisms of activation and deactivation of this heterodimeric enzyme are unknown. For deciphering them, functional domains can be overexpressed. We have probed the dynamics of the diatomic ligands NO and CO within the isolated heme domain β(1)(190) of human sGC by piconanosecond absorption spectroscopy...
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