Increases of ferrous iron oxidation activity and arsenic stressed cell growth by overexpression of Cyc2 in Acidithiobacillus ferrooxidans ATCC19859

摘要

Acidithiobacillus ferrooxidans plays an important role in bioleaching in reproducing the oxidant of minerals by oxidizing ferrous iron ( Fe2 + ) into ferric iron ( Fe3 + ). In order to increase ferrous iron oxidation activity, CYC2 is over expressed in Acidithiobacillus ferrooxidans ATCC19859. A recombinant plasmid pTCYC2 containing a 6 x His tag fused cycl gene under the control of Ptac promoter is constructed on the basis of the wide-host range plasmid pJRD215 , and transferred into Acidithiobacillus ferrooxidans ATCC19859 using conjugation gene transfer method, cycl gene transcription level was increased by 2. 63 fold in Acidithiobacillus ferrooxidans ( pTCYC2) compared with the control of the wild type strain measured by quantitative real-time PCR. The ferrous iron oxidation activity and the arsenic stressed cell growth of Acidithiobacillus ferrooxidans ( pTCYC2 ) were increased.