Crystal structure and biochemical characterization of a manganese superoxide dismutase from Chaetomium thermophilum

详细信息    查看全文

• 作者：Teemu Haikarainen ; Cl茅mence Frioux ; Li-Qing Zhnag ; Duo-Chuan Li ; Anastassios C. Papageorgiou
• 关键词：CtMnSOD ; Chaetomium thermophilum manganese superoxide dismutase ; SAA ; solvent accessible area ; RSAA ; relative solvent accessible area
• 刊名：Biochimica et Biophysica Acta - Proteins and Proteomics
• 出版年：February, 2014
• 年：2014
• 卷：1844
• 期：2
• 页码：422-429
• 全文大小：1480 K

文摘

A manganese superoxide dismutase from the thermophilic fungus Chaetomium thermophilum (CtMnSOD) was expressed in Pichia pastoris and purified to homogeneity. Its optimal temperature was 60 掳C with approximately 75% of its activity retained after incubation at 70 掳C for 60 min. Recombinant yeast cells carrying C. thermophilum mnsod gene exhibited higher stress resistance to salt and oxidative stress-inducing agents than control yeast cells. In an effort to provide structural insights, CtMnSOD was crystallized and its structure was determined at 2.0 脜 resolution. The overall architecture of CtMnSOD was found similar to other MnSODs with highest structural similarities obtained against a MnSOD from the thermotolerant fungus Aspergillus fumigatus. In order to explain its thermostability, structural and sequence analysis of CtMnSOD with other MnSODs was carried out. An increased number of charged residues and an increase in the number of intersubunit salt bridges and the Thr:Ser ratio were identified as potential reasons for the thermostability of CtMnSOD.