1GOW

BETA-GLYCOSIDASE FROM SULFOLOBUS SOLFATARICUS

1GOW の概要

• エントリーDOI: 10.2210/pdb1gow/pdb
• 分子名称: BETA-GLYCOSIDASE (2 entities in total)
• 機能のキーワード: hydrolase, beta-glycosidase
• 由来する生物種: Sulfolobus solfataricus
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 113530.46

構造登録者

Pearl, L.H.,Aguilar, C.F.,Sanderson, I. (登録日: 1996-09-19, 公開日: 1997-08-20, 最終更新日: 2024-02-07)

主引用文献

Aguilar, C.F.,Sanderson, I.,Moracci, M.,Ciaramella, M.,Nucci, R.,Rossi, M.,Pearl, L.H.
Crystal structure of the beta-glycosidase from the hyperthermophilic archeon Sulfolobus solfataricus: resilience as a key factor in thermostability.
J.Mol.Biol., 271:789-802, 1997

PubMed Abstract: 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.

PubMed: 9299327
DOI: 10.1006/jmbi.1997.1215

実験手法

X-RAY DIFFRACTION (2.6 Å)