2B83

A single amino acid substitution in the Clostridium beijerinckii alcohol dehydrogenase is critical for thermostabilization

2B83 の概要

• エントリーDOI: 10.2210/pdb2b83/pdb
• 関連するPDBエントリー: 1JQB
• 分子名称: NADP-dependent alcohol dehydrogenase, ZINC ION (3 entities in total)
• 機能のキーワード: cbadh mutant, metal binding, structural genomics, israel structural proteomics center, ispc, oxidoreductase
• 由来する生物種: Clostridium beijerinckii
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 151189.14

構造登録者

Goihberg, E.,Dym, O.,Israel Structural Proteomics Center (ISPC) (登録日: 2005-10-06, 公開日: 2006-09-19, 最終更新日: 2023-08-23)

主引用文献

Goihberg, E.,Dym, O.,Tel-Or, S.,Levin, I.,Peretz, M.,Burstein, Y.
A single proline substitution is critical for the thermostabilization of Clostridium beijerinckii alcohol dehydrogenase.
Proteins, 66:196-204, 2006

PubMed Abstract: Analysis of the three-dimensional structures of three closely related mesophilic, thermophilic, and hyperthermophilic alcohol dehydrogenases (ADHs) from the respective microorganisms Clostridium beijerinckii (CbADH), Entamoeba histolytica (EhADH1), and Thermoanaerobacter brockii (TbADH) suggested that a unique, strategically located proline residue (Pro100) might be crucial for maintaining the thermal stability of EhADH1. To determine whether proline substitution at this position in TbADH and CbADH would affect thermal stability, we used site-directed mutagenesis to replace the complementary residues in both enzymes with proline. The results showed that replacing Gln100 with proline significantly enhanced the thermal stability of the mesophilic ADH: DeltaT(1/2) (60 min) = + 8 degrees C (temperature of 50% inactivation after incubation for 60 min), DeltaT(1/2) (CD) = +11.5 degrees C (temperature at which 50% of the original CD signal at 218 nm is lost upon heating between 30 degrees and 98 degrees C). A His100 --> Pro substitution in the thermophilic TbADH had no effect on its thermostability. An analysis of the three-dimensional structure of the crystallized thermostable mutant Q100P-CbADH suggested that the proline residue at position 100 stabilized the enzyme by reinforcing hydrophobic interactions and by reducing the flexibility of a loop at this strategic region.

PubMed: 17063493
DOI: 10.1002/prot.21170

実験手法

X-RAY DIFFRACTION (2.25 Å)