Sandbox Reserved 1069: Difference between revisions

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OCA, Geoffrey C. Hoops, Madison Walberry, Austin S. Moore, Jessica Klingensmith, Kyle Colston

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 ===Zn<sup>2+</sup> Induced Conformation Change===
-Zinc induced conformation changes in the TMD and CTD leads to the major <scene name='69/694236/Outward-facinggreen/1'>outward-facing</scene> and <scene name='69/694236/Inward-facinggreen/1'>inward-facing conformations</scene>. [[Image:InwardVsOutward.png|300px|right|thumb| Figure 6. Side by side comparison of one monomer for the the outward-facing conformation of 3H90 and the inward-facing conformation of 3J1Z. TM1, TM2, TM4, and TM5 (yellow) pivot around TM3 and TM6 (green). The helices of the other half of the homodimer (blue) function identically.
+Zinc induced conformation changes in the TMD and CTD leads to the major <scene name='69/694236/Outward-facinggreen/1'>outward-facing</scene> and <scene name='69/694236/Inward-facinggreen/1'>inward-facing conformations</scene>. [[Image:InwardVsOutward.png|300px|right|thumb| Figure 6. Side by side comparison of one monomer for the the outward-facing conformation of 3H90 and the inward-facing conformation of 3J1Z. TM1, TM2, TM4, and TM5 (yellow) pivot around TM3 and TM6 (green). The helices of the other half of the homodimer (blue) function identically.]]
-]]
 The conformation change directly involved with Zn<sup>2+</sup>/H<sup>+</sup> antiport occurs in the TMD as helix pivoting controls what environment site A is available to. Conformation change occurs when the transmembrane helix pairs TM1, TM2, TM4, and TM5 pivot around cation binding site A.<ref>PMID:23341604</ref>
-It is believed that the energy for TMD conformation change comes from energy of binding each substrate. Changing to the outward from the inward-facing conformation causes a shift in the
+It is believed that the energy for TMD conformation change comes from energy of binding each substrate. Changing to the outward from the inward-facing conformation causes a shift transmembrane helicies TM1, TM2, TM4, and TM5 (Figure 6.) which disrupts Zn<sup>2+</sup> binding at site A. Due to the lack of resolution in the 3D structure of 3J1Z a direct comparison of binding site A for each conformation could not be done.<ref>PMID:23341604</ref> This decrease in binding affinity for Zn<sup>2+</sup> makes export to the periplasm possible. After Zn<sup>2+</sup> is exported and site A is either empty or bound to H<sup>+</sup>, the protein's conformation changes to the favored inward-facing conformation.
-transmembrane helicies (Figure 6.) which disrupts Zn<sup>2+</sup> binding at site A. This decrease in binding affinity for Zn<sup>2+</sup> makes export to the periplasm possible. After Zn<sup>2+</sup> is exported and site A is either empty or bound to H<sup>+</sup>, the protein's conformation changes to the favored inward-facing conformation.
 [[Image:FRET.png|200px|left|thumb| Figure 7. Labeled Cysteine resides measured with FRET showed the distance of the CTD of each monomer to be 24.0Å when saturated with Zn<sup>2+</sup>. Decrease in the Cys-Cys distance is indicative that both CTDs of YiiP were brought closer together.]]
 In contrast the main purpose of conformation change in the <scene name='69/694236/Outward-facinggreen/2'>CTD</scene> is to stabilize the YiiP dimer and to act as a Zn<sup>2+</sup> sensor.