ABSTRACT
A magnetic separator was used to separate magnetic bacteria based on their magnetotactic characteristics. Acidithiobacillus ferrooxidans, a bacterium that could synthesize intra-cellular nanometer magnetic particles, was investigated as an example. Strong magnetic and weak magnetic cells were separated and collected. On average, the number of the magnetic particles present in the strong magnetic cells is more than that of the weak magnetic cells. Moreover, semisolid-plate magnetophoresis showed that the magnetotaxis of strong magnetic cells was stronger than the weak magnetic cells. These results suggest that the magnetic separator can be used to isolate the magnetic bacteria, which will facilitate the research of magnetic bacteria.
Subject(s)
Acidithiobacillus , Metabolism , Bacteria , Metabolism , Bacterial Physiological Phenomena , Bacteriological Techniques , Methods , MagneticsABSTRACT
Acidithiobacillus ferrooxidans is able to synthesize intra-cellular electron-dense magnetite, which formed by BCM method in Acidithiobacillus ferrooxidans. The whole genome of the type strain Acidithiobacillus ferrooxidans ATCC 23270 was analyzed by bioinformatics and some homolog genes of functional ones in magnetotactic bacteria were available. This study analyzed the different concentration of Fe2+ stress response of mpsA, magA, thy and mamB gene by using real-time PCR analysis. Temporal genes expression profiles were examined in cells subjected to different concentration of FeSO4 x 7H2O stress, they reached to high expression under 150-200 mmol/L FeSO4 x 7H2O stress. With this new method study, it is possible that we could do deeper research to generate a comprehensive description of the mechanism that how Acidithiobacillus ferrooxidans synthesize the magnetic particles.
Subject(s)
Acidithiobacillus , Genetics , Metabolism , Amino Acid Sequence , Bacterial Proteins , Genetics , Metabolism , Dose-Response Relationship, Drug , Ferrous Compounds , Pharmacology , Gene Expression Profiling , Genes, Bacterial , Magnetics , Molecular Sequence Data , Stress, Physiological , Sulfur , MetabolismABSTRACT
In physiological property and growing environment aspects, there are some similarities between Acidthiobacillus ferrooxidans(ATF) and magnetotactic bacteria. ATF shows magnetotacxis under the microscope. The magnetosome can be extracted from ATF by using the extracting method of magnetosome from magnetotactic bacteria. The membrane of ATF was crushed by ultrasonic wave and the magnetosomes in the ATF which mainly contains Fe through chemical detection were attracted by using magnetite. After purifing with sucrose density gradient centrifugation and washing by PBS, the magnetosomes can be seen clearly through a transmission electron microscope. The results indicate there are a small amount of intracellular magnetosomes which made the ATF be magnetotactic under the applied magnetic field. It is the first time to find that ATF was magnetotactic. The magnetotaxis of ATF can be utilized and isolated by the magnetotactic properties to gain the high-performance ATF strains of mineral leaching, which have high activity and different magnetism.