5CSR

Crystal structure of triosephosphate isomerase from Thermoplasma acidophilium

5CSR の概要

• エントリーDOI: 10.2210/pdb5csr/pdb
• 関連するPDBエントリー: 5CSS
• 分子名称: Triosephosphate isomerase, GLYCEROL, CHLORIDE ION, ... (4 entities in total)
• 機能のキーワード: triosephoshate isomerase, thermoplasma acidophilium, tim, tpi, isomerase
• 由来する生物種: Thermoplasma acidophilum (strain ATCC 25905 / DSM 1728 / JCM 9062 / NBRC 15155 / AMRC-C165)
• 細胞内の位置: Cytoplasm : Q9HLB6
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 101293.67

構造登録者

Park, S.H.,Kim, H.S.,Song, M.K.,Park, H.S.,Han, B.W. (登録日: 2015-07-23, 公開日: 2016-06-08, 最終更新日: 2024-11-20)

主引用文献

Park, S.H.,Kim, H.S.,Park, M.S.,Moon, S.,Song, M.K.,Park, H.S.,Hahn, H.,Kim, S.J.,Bae, E.,Kim, H.J.,Han, B.W.
Structure and Stability of the Dimeric Triosephosphate Isomerase from the Thermophilic Archaeon Thermoplasma acidophilum.
Plos One, 10:e0145331-e0145331, 2015

PubMed Abstract: Thermoplasma acidophilum is a thermophilic archaeon that uses both non-phosphorylative Entner-Doudoroff (ED) pathway and Embden-Meyerhof-Parnas (EMP) pathway for glucose degradation. While triosephosphate isomerase (TPI), a well-known glycolytic enzyme, is not involved in the ED pathway in T. acidophilum, it has been considered to play an important role in the EMP pathway. Here, we report crystal structures of apo- and glycerol-3-phosphate-bound TPI from T. acidophilum (TaTPI). TaTPI adopts the canonical TIM-barrel fold with eight α-helices and parallel eight β-strands. Although TaTPI shares ~30% sequence identity to other TPIs from thermophilic species that adopt tetrameric conformation for enzymatic activity in their harsh physiological environments, TaTPI exists as a dimer in solution. We confirmed the dimeric conformation of TaTPI by analytical ultracentrifugation and size-exclusion chromatography. Helix 5 as well as helix 4 of thermostable tetrameric TPIs have been known to play crucial roles in oligomerization, forming a hydrophobic interface. However, TaTPI contains unique charged-amino acid residues in the helix 5 and adopts dimer conformation. TaTPI exhibits the apparent Td value of 74.6°C and maintains its overall structure with some changes in the secondary structure contents at extremely acidic conditions (pH 1-2). Based on our structural and biophysical analyses of TaTPI, more compact structure of the protomer with reduced length of loops and certain patches on the surface could account for the robust nature of Thermoplasma acidophilum TPI.

PubMed: 26709515
DOI: 10.1371/journal.pone.0145331

実験手法

X-RAY DIFFRACTION (1.94 Å)