Sandbox 154: Difference between revisions
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==== Active Site ==== | ==== Active Site ==== | ||
Upon actin binding on the plus end of the actin filament, the ATPase function is activated. The conformational change from G- to F- actin promotes the catalytic activity because of the 20° shift leading to a more closed binding site; this conformational change is stabilized also by the diagonal subdomain interaction between Leu110 and Thr194<ref name="oda"/>. | Upon actin binding on the plus end of the actin filament, the ATPase function is activated. The conformational change from G- to F- actin promotes the catalytic activity because of the 20° shift leading to a more closed binding site; this conformational change is stabilized also by the diagonal subdomain interaction between Leu110 and Thr194<ref name="oda"/>. | ||
As a result of these conformational changes, the Gln137 residue of actin is moved closer to the ATP-Ca<sup>2+</sup> ligand. Gln137 holds a water molecule, and placing it in close proximity to ATP allows for the gamma-phosphate | As a result of these conformational changes, the <scene name='Sandbox_154/2zwh_black_domains_gln137/1'>Gln137 residue</scene> of actin is moved closer to the ATP-Ca<sup>2+</sup> ligand. Gln137 holds a water molecule, and placing it in close proximity to ATP allows for cleavage of the gamma-phosphate. Release of the inorganic phosphate occurs via the conformational change of the flexible "D-loop" into an ordered alpha-helix<ref name="Graceffa"/>. | ||
== Function == | == Function == | ||
