nanobacteria


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nanobacteria

(nă′nō-băk-tēr-ē-ă)
A controversial entity, formerly thought to be the smallest known bacteria with intact gram-negative cell walls. They are now suspected of being inorganic precipitates of calcium carbonate.
Medical Dictionary, © 2009 Farlex and Partners

nanobacteria

Micro-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.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

nanobacteria

very 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.

Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005
References in periodicals archive ?
Ciftcioglu, "Nanobacteria: an alternative mechanism for pathogenic intra-and extracellular calcification and stone formation," Proceedings of the National Academy of Sciences, vol.
Among network rod-shaped nanobacteria is very common the presence of framboidal pyrite.
(128) As discussed above, FBS specifically poses numerous safety concerns, and even if processing can remove most of the FBS prior to clinical use, trace bovine proteins could remain sufficient to trigger an immune response and some contaminants (such as viruses, prions, and nanobacteria) are impossible to remove.
The rise and fall of nanobacteria. Scientific American, 302, 52-59.
No one knows where nanobacteria originate any more than we know where viruses or other bacteria come from.
Nanobacteria are cytotoxic, gram negative, atypical bacteria detected in bovine and human blood that has been implicated in a variety of disease states such as atherosclerotic heart disease and periodontal disease.
In 2001 he asked me to look at nanobacteria. In the process, I became aware of biofilm problems at the nano level.
ROB DUNN is an ecologist at North Carolina State University and the author of Every Living Thing: Man's Obsessive Quest to Catalog Life, From Nanobacteria to New Monkeys (2008).
In addition, the famous Mars meteorite ALH84001, which dates from about 4.5 billion years ago and was once believed to contain fossils of nanobacteria, also shows signs that it suffered a major impact 3.9 billion years ago.
On the other hand, as for the atherosclerotic coronary arterial disease, EDTA rendered the nanobacteria sensitive to tetracycline by breaking down their protective shells that are composed of calcium phosphate, thus leading to a decrease in the calcium score and a regress in the atherosclerotic plaque.
KEY WORDS: coronary heart disease, atherosclerosis, inflammation, Chlamydia pneumoniae, Helicobacter pylori, nanobacteria, antibiotic trials, azithromycin
In addition, nanobacteria may be important in clay mineral diagenesis in buried sandstones.