2c8l: Difference between revisions
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==Overview== | ==Overview== | ||
We present crystal structures of the calcium-free E2 state of the, sarcoplasmic reticulum Ca2+ -ATPase, stabilized by the inhibitor, thapsigargin and the ATP analog AMPPCP. The structures allow us to, describe the ATP binding site in a modulatory mode uncoupled from the, Asp351 phosphorylation site. The Glu439 side chain interacts with AMPPCP, via an Mg2+ ion in accordance with previous Fe2+ -cleavage studies, implicating this residue in the ATPase cycle and in magnesium binding., Functional data on Ca2+ mediated activation indicate that the crystallized, state represents an initial stage of ATP modulated deprotonation of E2, preceding the binding of Ca2+ ions in the membrane from the cytoplasmic, side. We propose a mechanism of Ca2+ activation of phosphorylation leading, directly from .. | We present crystal structures of the calcium-free E2 state of the, sarcoplasmic reticulum Ca2+ -ATPase, stabilized by the inhibitor, thapsigargin and the ATP analog AMPPCP. The structures allow us to, describe the ATP binding site in a modulatory mode uncoupled from the, Asp351 phosphorylation site. The Glu439 side chain interacts with AMPPCP, via an Mg2+ ion in accordance with previous Fe2+ -cleavage studies, implicating this residue in the ATPase cycle and in magnesium binding., Functional data on Ca2+ mediated activation indicate that the crystallized, state represents an initial stage of ATP modulated deprotonation of E2, preceding the binding of Ca2+ ions in the membrane from the cytoplasmic, side. We propose a mechanism of Ca2+ activation of phosphorylation leading, directly from the compact E2-ATP form to the Ca2E1-ATP state. In addition, a role of Glu439 in ATP modulation of other steps of the functional cycle, is suggested. | ||
==About this Structure== | ==About this Structure== | ||
2C8L is a | 2C8L is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus] with NA and TG1 as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Calcium-transporting_ATPase Calcium-transporting ATPase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.6.3.8 3.6.3.8] Structure known Active Site: AC1. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2C8L OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: phosphorylation]] | [[Category: phosphorylation]] | ||
''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Mon Nov 5 15:25:15 2007'' | ||
