Sandbox Reserved 969: Difference between revisions
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====Open Conformation==== | ====Open Conformation==== | ||
Channel opening is a '''conserved mechanism'''.The inner helix '''twist''' and '''bend''' thanks to a<scene name='60/604488/Glycine_conserved/1'> conserved glycine residue Gly87</scene> which is considered as the '''gating hinge'''. After this bending, the inner helices twist of 45° around their helical helix and the outer helix tilt tangentially in the same direction by 11° without any twisting motion. As all of helix twist or move inside of a subunit, intra-subunit interactions between inner and outer helix don’t differ a lot. On the contrary, inter-subunit interactions between neighboring inner helix change. In fact, Phe92 swings away and points its side chain towards the central ion conduction pathway due to inner helix bending and the hydrophobic patch slides along the neighboring inner helix by two helical turns and forms new Van der Waals contacts with Phe85. This resulted in a '''disruption of the bundle crossing''' and so intra- and inter- subunits interactions in the open state become less important than in the close state. <ref>PMID: 19098917</ref> | Channel opening is a '''conserved mechanism'''.The inner helix '''twist''' and '''bend''' thanks to a<scene name='60/604488/Glycine_conserved/1'> conserved glycine residue Gly87</scene> which is considered as the '''gating hinge'''. After this bending, the inner helices twist of 45° around their helical helix and the outer helix tilt tangentially in the same direction by 11° without any twisting motion. As all of helix twist or move inside of a subunit, intra-subunit interactions between inner and outer helix don’t differ a lot. On the contrary, inter-subunit interactions between neighboring inner helix change. In fact, Phe92 swings away and points its side chain towards the central ion conduction pathway due to inner helix bending and the hydrophobic patch slides along the neighboring inner helix by two helical turns and forms new Van der Waals contacts with <scene name='60/604488/Phe85/1'>Phe 85 </scene>. This resulted in a '''disruption of the bundle crossing''' and so intra- and inter- subunits interactions in the open state become less important than in the close state. <ref>PMID: 19098917</ref> | ||
[[Image:open_structure.jpg|right|100px|The structure of the open complex]] | [[Image:open_structure.jpg|right|100px|The structure of the open complex]] | ||
