•Introduction
•Method
•Results
•Conclusion
•References
•
These bacteria occur in deeper region:-
Many
MTB are able to survive only in environments with very limited oxygen, and some
can exist only in completely anaerobic environments Magnetotactic bacteria are
found in the sediments of many aquatic environments .
§These
are Gram-negative members of the Domain Bacteria and belong phylogenetically to
various subgroups of the Proteobacteria.
§
They are motile by means of flagella
§Magnetotactic
bacteria produce their magnetic particles in chains
§The
most abundant type of MTB occurring in
environmental samples, especially sediments, are coccoid cells
possessing two flagellar bundles on a some what flattened side. This
"bilophotrichous" type of flagellation gave rise to the tentative .
§They
are ubiquitous in aquatic habitats and cosmopolitan in distribution. Locally
confined to or slightly below the oxic-anoxic interface.
•MTB orient and
migrate along geomagnetic field lines –
this ability is based on intracellular magnetic structures known as
magnetosomes. They contain 15 to 20 magnetite crystals that together
act like compass needle to orient magnetotactic bacteria
in geomagnetic fields.
•Each magnetite
crystal with in a magnetosome is surrounded by a lipid bilayer ,and
specific soluble and transmembrane proteins are sorted to
the membrane.
•Overall, magnetosome
crystals have high chemical purity, narrow size ranges,
species-specific crystal morphologies and exhibit specific
arrangements with in the cell. These features indicate that the formation of
magnetosomes is under precise biological control and is
mediated biomineralization
•Invagination of the cytoplasmic
membrane and vesicle formation for the magnetosome membrane precursor
•Accumulation of ferrous/ferric
ions in the cell and the vesicles
•Strictly controlled iron
oxidation–reduction
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