7WNL

Crystal structure of a mutant Staphylococcus equorum manganese superoxide dismutase K38R and A121Y

7WNL の概要

• エントリーDOI: 10.2210/pdb7wnl/pdb
• 関連するPDBエントリー: 5x2j 6m30 7ddw 7w6w 7wnk
• 分子名称: Superoxide dismutase, DI(HYDROXYETHYL)ETHER, MANGANESE (II) ION, ... (7 entities in total)
• 機能のキーワード: superoxide dismutase, staphylococcus equorum, oxidoreductase
• 由来する生物種: Staphylococcus equorum
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 95244.52

構造登録者

Retnoningrum, D.S.,Yoshida, H.,Artarini, A.A.,Ismaya, W.T. (登録日: 2022-01-18, 公開日: 2023-01-25, 最終更新日: 2023-11-29)

主引用文献

Retnoningrum, D.S.,Yoshida, H.,Pajatiwi, I.,Muliadi, R.,Utami, R.A.,Artarini, A.,Ismaya, W.T.
Introducing Intermolecular Interaction to Strengthen the Stability of MnSOD Dimer.
Appl.Biochem.Biotechnol., 195:4537-4551, 2023

PubMed Abstract: Manganese superoxide dismutase from Staphylococcus equorum (MnSODSeq) maintains its activity upon treatments like a wide range of pH, addition of detergent and denaturing agent, exposure to ultraviolet light, and heating up to 50 °C. The enzyme dimer dissociates at 52-55 °C, while its monomer unfolds at 63-67 °C. MnSOD dimeric form is indispensable for the enzyme activity; therefore, strengthening the interactions between the monomers is the most preferred strategy to improve the enzyme stability. However, to date, modification of MnSODSeq at the dimer interface has been unfruitful despite excluding the inner and outer sphere regions that are important to the enzyme activity. Here, a new strategy was developed and K38R-A121E/Y double substitutions were proposed. These mutants displayed similar enzyme activity to the wild type. K38R-A121E dimer was thermally more stable and its monomer stability was similar to the wild type. The thermal stability of K38R-A121Y dimer was similar to the wild type but its monomer was thermally less stable. In addition, the structure of the previously reported L169W mutant was also elucidated. The L169W mutant structure showed that intramolecular modification can decrease flexibility of the MnSODSeq monomer and leads to a less stable enzyme with similar activity to the wild type. Thus, while the enzyme activity depends on arrangement of residues in the dimer interface, the stability appears to depend more on its monomeric architecture. Furthermore, in the L169W structure in complex with azide, which is a specific inhibitor for MnSOD, one of the azide molecules was present in the dimer interface region that previously has been identified to involve in the enzymatic reaction. Nevertheless, the present results show that an MnSODSeq mutant with better thermal stability has been obtained.

PubMed: 36701098
DOI: 10.1007/s12010-023-04347-7

実験手法

X-RAY DIFFRACTION (1.51 Å)