Molecular cloning, expression, purification and characterization of thioredoxin from Antarctic sea-ice bacteria Pseudoalteromonas sp AN178

作者：Wang Quanfu; Hou Yanhua^*; Qu Junjie; Hong Yanyan; Lin Yifei; Han Xiao

来源：Molecular Biology Reports, 2013, 40(12): 6587-6591.

DOI：10.1007/s11033-013-2771-4

• Cloning
• Thioredoxin
• Pseudoalteromonas sp.
• Sea-ice
• Antarctic

Thioredoxin (Trx) is a highly conserved and multi-functional protein that plays a pivotal role in maintaining the redox state of the cell and in protecting the cell against oxidative stress. Trx gene from Antarctic sea-ice bacteria Pseudoalteromonas sp. AN178 was cloned and expressed as soluble protein in Escherichia coli (designated as PsTrx). Trx gene consisted of an open reading frame of 324-bp nucleotides encoding a protein of 108 amino acids with a calculated molecular mass of 11.88 kDa. The deduced protein included the conserved Cys-Gly-Pro-Cys active-site sequence. After purification by a single step Ni-NTA affinity chromatography, recombinant PsTrx with a high specific activity of 96.67 U/mg was obtained. The purified PsTrx had an optimal temperature and pH of 25 A degrees C and 7.0, respectively, and showed about 55 % of the residual catalytic activity even at 0-10 A degrees C. It had high tolerance to a wide range of NaCl concentrations (0-2 M NaCl) and was stable in the presence of H2O2. This research suggested that PsTrx displayed unique catalytic properties.

• 出版日期2013-12
• 单位哈尔滨工业大学