Transformation Studies with Thiobacillus Ferrooxidans as a Prerequisite for Strain Improvement for Strategic Metals Recovery, Phase 1.

摘要

The goal of the research program was to develop a molecular biological system that would permit modification of Thiobacillus ferrooxidans strains to improve the rate and broaden the specificity of metal leaching. Researchers demonstrated that it is possible to obtain antibiotic-resistant mutants of thiobacillus ferrooxidans through classical mutagenesis and selection techniques. A pH optimum for genetic transformation of 5.0 was determined, based on plasmid and antibiotic stability and the ability of T. ferrooxidans to withstand the transformation manipulations. A T. ferrooxidans plasmid was isolated and recombined with the E. coli plasmid pBR325 to form a hybrid plasma, which one might expect to replace in both organisms; the plasmid could be maintained in E. coli. To test plasmid maintainance in T. Ferrooxidans, the E. coli kanamycin resistance gene was inserted into the hybrid. Transformation experiments failed to produce kanamycin resistant T. ferrooxidans. Because of the failure, isolation of the T. ferrooxidans kanamycin resistance determinant was not completed.