SOME claim they are a new life form responsible for a wide range of diseases, including the calcification of the arteries that afflicts us all as we age. Others say they are simply too small to be living creatures. Now a team of doctors has entered the fray surrounding the existence or otherwise of nanobacteria. After four years' work, the team, based at the Mayo Clinic in Rochester, Minnesota, has come up with some of the best evidence yet that they do exist. Cautiously titled "Evidence of nanobacterial-like structures in human calcified arteries and cardiac valves", the paper by John Lieske and his team describes how they isolated minuscule cell-like structures from diseased human arteries. These particles self-replicated in culture, and could be identified with an antibody and a DNA stain. "The evidence is suggestive," is all Lieske claims. Critics are not convinced. "I just don't think this is real," says Jack Maniloff of the University of Rochester in New York. "It is the cold fusion of microbiology." John Cisar of the National Institutes of Health is equally sceptical. "There are always people who are trying to keep this alive. It's like it is on life-support." The first claims about nanobacteria came from geologists studying tiny cell-like structures in rock slices. But in 1998 the debate took a different twist when Olavi Kajander and Neva Ciftcioglu of the University of Kuopio in Finland claimed to have found nanobacteria, surrounded by a calcium-rich mineral called apatite, in human kidney stones.
Objections were raised immediately. Many of the supposed nanobacteria were less than 100 nanometres across, smaller than many viruses, which cannot replicate independently. Maniloff's work suggests that to contain the DNA and proteins needed to function, a cell must be at least 140 nanometres across. Kajander and Ciftcioglu, however, insisted that they had observed the nanoparticles self-replicating in a culture medium and claimed to have identified a unique Page: 1 2 3 4 Related biology news :1
Contact: Claire Bowles
. Evidence of nanobacterial-like structures found in human calcified arteries and cardiac valves2
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