title: Characterization of the interaction between superoxide dismutase and 2-oxoisovalerate dehydrogenase.
abstract: Thermophiles are attractive microorganisms to study the adaptation of life in high temperature environment. It is revealed that superoxide dismutase (SOD) is essential for thermoadaptation of thermophiles. However, the SOD-mediated pathway of thermoadaptation remains unclear. To address this issue, the proteins interacted with SOD were characterized in Thermus thermophilus in this study. Based on co-immunoprecipitation and Western blot analyses, the results showed that 2-oxoisovalerate dehydrogenase α subunit was bound to SOD. The isothermal titration calorimetry analysis showed the existence of the interaction between SOD and 2-oxoisovalerate dehydrogenase α subunit. The bacterial two-hybrid data indicated that SOD was directly interacted with 2-oxoisovalerate dehydrogenase α subunit. Gene site-directed mutagenesis analysis revealed that the intracellular interaction between SOD and 2-oxoisovalerate dehydrogenase α subunit was dependent on their whole molecules. Therefore our study presented a novel aspect of SOD in the thermoadaptation of thermophiles by interaction with dehydrogenase, a key enzyme of tricarboxylic acid cycle.
authors.affiliation: Key Laboratory of Conservation Biology for Endangered Wildlife of Ministry of Education and College of Life Sciences, Zhejiang University, Hangzhou 310058, People's Republic of China; School of Chemistry and Material Engineering, Fuyang Teachers College, Fuyang 236037, People's Republic of China.
authors.forename: Chongfu
authors.initials: C
authors.lastname: Song
authors.affiliation: Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, People's Republic of China.
authors.forename: Hebin
authors.initials: H
authors.lastname: Li
authors.affiliation: School of Chemistry and Material Engineering, Fuyang Teachers College, Fuyang 236037, People's Republic of China.
authors.forename: Liangquan
authors.initials: L
authors.lastname: Sheng
authors.affiliation: Key Laboratory of Conservation Biology for Endangered Wildlife of Ministry of Education and College of Life Sciences, Zhejiang University, Hangzhou 310058, People's Republic of China. Electronic address: zxb0812@zju.edu.cn.
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Zhang
mesh_terms: D050645:2-Oxoisovalerate Dehydrogenase (Acylating) / Q000737:chemistry / Q000378:metabolism*; D000222:Adaptation, Physiological; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D025941:Protein Interaction Mapping; D013482:Superoxide Dismutase / Q000737:chemistry / Q000378:metabolism*; D013816:Thermodynamics; D016963:Thermus thermophilus / Q000201:enzymology*
chemical_list: D001426:Bacterial Proteins; D013482:Superoxide Dismutase; D050645:2-Oxoisovalerate Dehydrogenase (Acylating)
keywords: 2-Oxoisovalerate dehydrogenase α subunit; Protein interaction; Superoxide dismutase; Thermoadaptation; Thermus thermophilus