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The eosinophilic Thiobacillus ferrooxidans (Acidithiobacillus ferrooxidans) is an obligate autotrophic extremely acidophilic Thiobacillus, it is widely distributed in the sulfide deposit, acidic mine water and soil, bacteria metallurgy, coal desulfurization and sulfur wastewater treatment and other aspects play an important role, the the bioleaching bacteria present study is the most in-depth, the most widely used. It under acidic conditions, Fe2 oxide Fe3, or elemental sulfur or reducing sulfur is oxidized to sulfuric acid, and rely on the these inorganics oxidation process to obtain energy. Fe3 generated in the leaching process is to promote the leaching of other metal ores oxidants, and therefore closely linked ferrous oxidation capability of the bacteria with the ore leaching. In the practical application of the process, these bacteria grow slowly, on behalf of long cells was low, limiting its production efficiency, but also a lot of inconvenience to the research work. Therefore, genetic transformation, the imperative to improve the bacteria ferrous oxidation capacity. In this thesis eosinophilic Thiobacillus ferrooxidans iron oxidation system electron transport chain gene clone identification, and connect with a broad host plasmid, placed a strong promoter tac, re-import the obtained expression in bacteria, research and compare the build iron oxidation activity of strains, growth conditions, and changes in the leaching capacity, and provide the basis for the theory and methods for the transformation of these bacteria. Cytochrome oxidase gene A.ferrooxidans19859 in cox, copper-containing protein gene cup, as well as ferrous oxidase gene iro were cloned into pUC18 plasmid the then the subcloned pJRD215 or pMSD2, construct the recombinant plasmid pTCOX, pTCUP and pTIRO. By conjugal transfer the these plasmids into A.ferrooxidans19859,. The then by colony PCR and other methods to verify that successfully constructed genetic engineering the the bacteria A.ferrooxidans (pTCOX), A.ferrooxidans (pTCUP) and A.ferrooxidans (pTIRO). Constructed strains of plasmid stability, ferrous consumption rate, oxidation-reduction potential, the growth curves and the efficiency of leaching was measured and compared. The results showed that the recombinant plasmid can be stably inherited iron oxidation activity A.ferrooxidans (pTCOX) greatly increased. Then to A.ferrooxidans wild-type control, the alaS gene as an internal use the fluorescence quantitative A.ferrooxidans (pTCOX) rus manipulation of gene expression within the sub-analysis. Provide theoretical guidance for the Thiobacillus ferrooxidans eosinophilic further genetic improvement work.
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