title: Towards Al-induced manganese-containing superoxide dismutase inactivation and conformational changes: an integrating study with docking simulations.
abstract: Superoxide dismutase (SOD, EC 1.15.1.1) plays an important antioxidant defense role in skins exposed to oxygen. We studied the inhibitory effects of Al(3+) on the activity and conformation of manganese-containing SOD (Mn-SOD). Mn-SOD was significantly inactivated by Al(3+) in a dose-dependent manner. The kinetic studies showed that Al(3+) inactivated Mn-SOD follows the first-order reaction. Al(3+) increased the degree of secondary structure of Mn-SOD and also disrupted the tertiary structure of Mn-SOD, which directly resulted in enzyme inactivation. We further simulated the docking between Mn-SOD and Al(3+) (binding energy for Dock 6.3: -14.07 kcal/mol) and suggested that ASP152 and GLU157 residues were predicted to interact with Al(3+), which are not located in the Mn-contained active site. Our results provide insight into the inactivation of Mn-SOD during unfolding in the presence of Al(3+) and allow us to describe a ligand binding via inhibition kinetics combined with the computational prediction.
authors.affiliation: School of Life Science, Ningxia University, Yinchuan 750021, China.
authors.forename: Jiang-Liu
authors.initials: JL
authors.lastname: Yang
authors.forename: Shang-Jun
authors.initials: SJ
authors.lastname: Yin
authors.forename: Yue-Xiu
authors.initials: YX
authors.lastname: Si
authors.forename: Zhi-Rong
authors.initials: ZR
authors.lastname: Lü
authors.forename: Xiangrong
authors.initials: X
authors.lastname: Shao
authors.forename: Daeui
authors.initials: D
authors.lastname: Park
authors.forename: Hae Young
authors.initials: HY
authors.lastname: Chung
authors.forename: Hai-Meng
authors.initials: HM
authors.lastname: Zhou
authors.forename: Guo-Ying
authors.initials: GY
authors.lastname: Qian
authors.forename: Zi-Ping
authors.initials: ZP
authors.lastname: Zhang