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nanobacteriaMicro-organisms less than 0.1 (micrometre) long and surrounded by a mineralized shell, that were first described in mid-1998. It is claimed that cells infected with these bacteria develop mineral deposits and suggested that they may be the cause of kidney stones and a range of other diseases that feature calcification. Critics have suggested that these are simply normal bacteria that have shrunk and become calcified. Further study is required.
nanobacteriavery small, nano-sized (about 20–200 nm in diameter) putative bacteria, representing the smallest known replicating bacteria. They have been detected in blood of humans and animals. Their small size means that they can pass through sterile filters (0.1 μm pore size). The species name Nanobacterium sanguineum reflects the small size and habitat. Nanobacteria appear to belong to the Proteobacteria (see PURPLE BACTERIA or to be ancestors of the group. They are believed to cause calcification in many human pathological states, such as kidney stones.
Particles resembling the nanobacteria have been found in sedimentary rock/Martian meteorite. These have been termed Nannobacteria.
It should be noted that there are opponents of the nanobacteria hypothesis, who claim that nanobacteria are smaller than the minimum possible for living cells and are instead artefacts of chemical/geochemical reactions of non-living material.