Techniques for the Isolation of Magnetotactic Bacteria

Magnetotactic bacteria and magnetosomes'Magnetotactic Bacteria' are metabolically diverse Gram negative prokaryotes that swim in the direction of external magnetic field.This swimming behavior is referred to as "magnetotaxis" [1,5].In the northern hemisphere, MTB swim towards the south pole of a magnet and viceversa is true in the southern hemisphere and either ways at the geomagnetic equator [2].MTB are fast moving organisms and their movement is due to the presence of flagella [5,14].Magnetotaxis is an important phenomenon in these bacteria as they are microaerophilc, facultatively microaerophilic or obligately anaerobic in nature.They are therefore found in abundance at the oxic-anoxic transition zone (OATZ) and prefer to grow at low oxygen concentrations prevailing in Abstract Magnetotactic bacteria (MTB), a diverse group of ubiquitously occurring Gram negative procaryotes are currently the subject of interdisciplinary research.The unique trait of synthesis and biomineralization of nano-sized magnetic particles in the ideal range of 30 to 120 nm makes them suitable for biomedical and biotechnological applications.However, research in this field has not reached a commercial scale as these bacteria are notoriously difficult to culture.Culturing this metabolically versatile group of bacteria on defined medium is still a challenging task even though a few MTB strains have been isolated and purified in the past.Scientists worldwide are developing different strategies to trap MTB under artificial laboratory conditions.This review summarizes various apparatus, setups and media formulations designed for obtaining axenic MTB strains since their discovery by Richard Blakemore in 1975.