1gow: Difference between revisions
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==Overview== | ==Overview== | ||
Enzymes from hyperthermophilic organisms must operate at temperatures, which rapidly denature proteins from mesophiles. The structural basis of, this thermostability is still poorly understood. Towards a further, understanding of hyperthermostability, we have determined the crystal, structure of the beta-glycosidase (clan GH-1A, family 1) from the, hyperthermophilic archaeon Sulfolobus solfataricus at 2.6 A resolution., The enzyme is a tetramer with subunit molecular mass at 60 kDa, and, crystallises with half of the tetramer in the asymmetric unit. The, structure is a (betaalpha)8 barrel, but with substantial elaborations, between the beta-strands and alpha-helices in each repeat. The active site, occurs at the centre of the top face of the barrel and is connected to the, surface by a ... | Enzymes from hyperthermophilic organisms must operate at temperatures, which rapidly denature proteins from mesophiles. The structural basis of, this thermostability is still poorly understood. Towards a further, understanding of hyperthermostability, we have determined the crystal, structure of the beta-glycosidase (clan GH-1A, family 1) from the, hyperthermophilic archaeon Sulfolobus solfataricus at 2.6 A resolution., The enzyme is a tetramer with subunit molecular mass at 60 kDa, and, crystallises with half of the tetramer in the asymmetric unit. The, structure is a (betaalpha)8 barrel, but with substantial elaborations, between the beta-strands and alpha-helices in each repeat. The active site, occurs at the centre of the top face of the barrel and is connected to the, surface by a radial channel which becomes a blind-ended tunnel in the, tetramer, and probably acts as the binding site for extended, oligosaccharide substrates. Analysis of the structure reveals two features, which differ significantly from mesophile proteins; (1) an unusually large, proportion of surface ion-pairs involved in networks that cross-link, sequentially separate structures on the protein surface, and (2) an, unusually large number of solvent molecules buried in hydrophilic cavities, between sequentially separate structures in the protein core. These, factors suggest a model for hyperthermostability via resilience rather, than rigidity. | ||
==About this Structure== | ==About this Structure== | ||
1GOW is a | 1GOW is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Sulfolobus_solfataricus Sulfolobus solfataricus]. Active as [http://en.wikipedia.org/wiki/Beta-galactosidase Beta-galactosidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.23 3.2.1.23] Structure known Active Sites: CTA and CTB. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1GOW OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: hydrolase]] | [[Category: hydrolase]] | ||
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