Transactions of Nonferrous Metals Society of China
JOURNAL OF RAILWAY SCIENCE AND ENGINEERING
|Vol. 18 No. 6 December 2008|
iron-containing superoxide dismutase from Acidithiobacillus ferrooxidans
（1. School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China;
2. School of Life Science, Hunan University of Science and Technology, Xiangtan 411201, China）
Abstract:The superoxide dismutase(SOD) from Acidithiobacillus ferrooxidans may play an important role in its tolerance to the extremely toxic and oxidative environment of bioleaching. This gene was cloned and then successfully expressed in Escherichia coli. The expressed protein was finally purified by one-step affinity chromatography to homogeneity and observed to be dimer according to SDS-PAGE and MALDI-TOF-MS. The metal content determination and optical spectra results of the recombinant protein confirmed that the protein was an iron-containing superoxide dismutase. Molecular modeling for the protein revealed that the iron atom was ligated by His26, His75, Asp158 and His162.
Key words: Acidithiobacillus ferrooxidans; superoxide dismutase; expression; purification; molecular modeling; His-tag