Application of principal component analysis to determine the key structural features contributing to iron superoxide dismutase thermostability.
Iron superoxide dismutase (Fe-SOD) is predominantly found in bacteria and mitochondria. The thermal stability of Fe-SOD from different sources can vary dramatically. We have studied the influence of structural parameters on Fe-SOD thermostability by principal component analysis (PCA). The results show that an increased α-helical and turn content, an increased α-helix and loop length, an increase in the number of main-main chains and charged-uncharged hydrogen bonds, a decrease in the 3(10) -helix content, and a decreased β-strand and loop length are all important factors for Fe-SOD thermostability. Interestingly, the use of charged residues to form salt bridges is tendentious in thermophilic Fe-SOD. Negatively charged Arg and positively charged Glu are efficiently used to form salt bridges. The cooperative action of the exposed area, the hydrogen bonds, and the secondary structure plays a crucial role in resisting high temperatures, which demonstrates that the increased stability of thermophilic Fe-SOD is provided by several structural factors acting together.
Jiangnan University, Wuxi, People's Republic of China. yr_ding@jiangnan.edu.cn
Yanrui
Y
Ding
Yujie
Y
Cai
Yonggang
Y
Han
Bingqiang
B
Zhao
Lei
L
Zhu
D001120:Arginine / Q000737:chemistry*; D004795:Enzyme Stability; D018698:Glutamic Acid / Q000737:chemistry*; D006358:Hot Temperature; D006860:Hydrogen Bonding; D007527:Isoenzymes / Q000737:chemistry; D025341:Principal Component Analysis; D011387:Prokaryotic Cells / Q000737:chemistry / Q000201:enzymology*; D017433:Protein Structure, Secondary; D012492:Salts / Q000737:chemistry; D055672:Static Electricity; D013482:Superoxide Dismutase / Q000737:chemistry*; D013816:Thermodynamics
D007527:Isoenzymes; D012492:Salts; D018698:Glutamic Acid; D001120:Arginine; D013482:Superoxide Dismutase