A PRELIMINARY REPORT ON THE ISOLATION AND IDENTIFICATION OF MAGNETOTACTIC BACTERIA FROM IRAN ENVIRONMENT

摘要

Several species of Magnetotactic bacteria have been discovered recently. These bacteria synthesize intracellular magnetic nanoparticles in specific sizes and shapes and arrange them in chains. These particles called magnetosomes and can be used for drug-delivery, cell-targeting and hyperthermia. Magnetotactic bacteria navigate along the magnetic field; this process is known as ‘magnetotaxis’ which may be very useful in robotic technology. In this research, two species of magnetotactic bacteria were isolated; freshwater specimens were collected from Karkheh River and marine specimens were collected from the Caspian Sea. After enrichment, two species of the Magnetotactic bacteria were isolated using a specific solid media culturing. The response of the two isolates to the magnetic field was observed by an optical microscope. SEM photos showed that the freshwater and marine bacteria are rod shaped. TEM images showed chains of magnetosomes in the bacterial cells. Also magnetic behavior of the magnetosomes was investigated by alternating-gradient-force magnetometer, indicating that the magnetosomes have superparamagnetic-to-single-domain properties.