4MB1

The Structure of MalL mutant enzyme G202P from Bacillus subtilus

4MB1 の概要

• エントリーDOI: 10.2210/pdb4mb1/pdb
• 関連するPDBエントリー: 4M56 4M8U 4MAZ
• 分子名称: Oligo-1,6-glucosidase 1, 2-AMINO-2-HYDROXYMETHYL-PROPANE-1,3-DIOL, CALCIUM ION, ... (4 entities in total)
• 機能のキーワード: tim barrel, alpha glucosidase, hydrolase
• 由来する生物種: Bacillus subtilis subsp. subtilis
• 細胞内の位置: Cytoplasm: O06994
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 66365.46

構造登録者

Hobbs, J.K.,Jiao, W.,Easter, A.D.,Parker, E.J.,Schipper, L.A.,Arcus, V.L. (登録日: 2013-08-19, 公開日: 2013-09-25, 最終更新日: 2024-02-28)

主引用文献

Hobbs, J.K.,Jiao, W.,Easter, A.D.,Parker, E.J.,Schipper, L.A.,Arcus, V.L.
Change in heat capacity for enzyme catalysis determines temperature dependence of enzyme catalyzed rates.
Acs Chem.Biol., 8:2388-2393, 2013

PubMed Abstract: The increase in enzymatic rates with temperature up to an optimum temperature (Topt) is widely attributed to classical Arrhenius behavior, with the decrease in enzymatic rates above Topt ascribed to protein denaturation and/or aggregation. This account persists despite many investigators noting that denaturation is insufficient to explain the decline in enzymatic rates above Topt. Here we show that it is the change in heat capacity associated with enzyme catalysis (ΔC(‡)p) and its effect on the temperature dependence of ΔG(‡) that determines the temperature dependence of enzyme activity. Through mutagenesis, we demonstrate that the Topt of an enzyme is correlated with ΔC(‡)p and that changes to ΔC(‡)p are sufficient to change Topt without affecting the catalytic rate. Furthermore, using X-ray crystallography and molecular dynamics simulations we reveal the molecular details underpinning these changes in ΔC(‡)p. The influence of ΔC(‡)p on enzymatic rates has implications for the temperature dependence of biological rates from enzymes to ecosystems.

PubMed: 24015933
DOI: 10.1021/cb4005029

実験手法

X-RAY DIFFRACTION (1.4 Å)