Nitric Oxide Synthase: Difference between revisions
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In order for Nos to be active it has to dimerize and bind H<sub>4</sub>B. The two monomers are held together by a single structural <applet load='2g6h' size='300' frame='true' align='right' caption='Zinc' /><scene name='Nitric_oxide_synthase/Zink/2'>zinc ion</scene> | In order for Nos to be active it has to dimerize and bind H<sub>4</sub>B. The two monomers are held together by a single structural <applet load='2g6h' size='300' frame='true' align='right' caption='Zinc' /><scene name='Nitric_oxide_synthase/Zink/2'>zinc ion</scene> | ||
which is situated at the interface of the dimer | which is situated at the interface of the dimer<ref name="penta"/>. The zinc ion is tetrahedrally coordinated and has four cysteins bound as ligands (two from each monomer - Cys109 and Cys104). Further, it is found that zinc binds together the oxygenase domains of the monomers. The zinc ion is found at a region which connects the N-terminal hook and the subunit core. The coordination of zinc arranges the N-terminal hooks so that they interact with their own subunit. However, when there is no zinc ion present, two of the thiolate | ||
ligands (cysteines) form a disulfide bond connecting the two subunits<ref>PMID: 10562539</ref>. | ligands (cysteines) form a disulfide bond connecting the two subunits<ref>PMID: 10562539</ref>. | ||
