Journal:IUCrJ:S2052252519005372
From Proteopedia
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Using X-ray crystallography, high-resolution structural models of different forms of GgH could be obtained. These detailed views of GgH revealed several important aspects of its mode of action, including its oligomeric organization, with the homotetramer present in the crystals being fully compatible with the architecture of the active form of GgH in solution, assessed by small-angle X-ray scattering (SAXS) using synchrotron radiation. The crystallographic structures of unliganded and substrate-bound GgH further revealed the existence of a coordinated movement of several surface loops in the vicinity of the active site during the catalytic cycle of the enzyme. Therefore, the active site of GgH is only completely structured upon substrate binding, with the mobile loops shielding the bound compounds from the solvent and facilitating the enzymatic reaction. Reversal of this movement opens up the active site of GgH, allowing product release and readying the enzyme for another catalytic cycle. | Using X-ray crystallography, high-resolution structural models of different forms of GgH could be obtained. These detailed views of GgH revealed several important aspects of its mode of action, including its oligomeric organization, with the homotetramer present in the crystals being fully compatible with the architecture of the active form of GgH in solution, assessed by small-angle X-ray scattering (SAXS) using synchrotron radiation. The crystallographic structures of unliganded and substrate-bound GgH further revealed the existence of a coordinated movement of several surface loops in the vicinity of the active site during the catalytic cycle of the enzyme. Therefore, the active site of GgH is only completely structured upon substrate binding, with the mobile loops shielding the bound compounds from the solvent and facilitating the enzymatic reaction. Reversal of this movement opens up the active site of GgH, allowing product release and readying the enzyme for another catalytic cycle. | ||
Finally, the different complexes of GgH with substrates and substrate analogues allowed to infer the molecular details of the reaction mechanism of this inverting hydrolase and to ascribe the functional roles of highly conserved residues in this class of enzymes. | Finally, the different complexes of GgH with substrates and substrate analogues allowed to infer the molecular details of the reaction mechanism of this inverting hydrolase and to ascribe the functional roles of highly conserved residues in this class of enzymes. | ||
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| + | <scene name='81/814833/Cv/2'>Quaternary structure of MhGgH</scene>. Monomers are coloured green (molecule A), wheat (molecule B), cyan (molecule C) and blue (molecule D). Interfaces A:B and A:C are indicated. The serine molecules found in the active site region are represented by salmon spheres. | ||
<b>References</b><br> | <b>References</b><br> | ||
Revision as of 12:25, 2 May 2019
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This page complements a publication in scientific journals and is one of the Proteopedia's Interactive 3D Complement pages. For aditional details please see I3DC.
