Author(s):      Mathew, Grace; McKay, David S.; Ciftcioglu, Neva

Abstract:       Biologists typically define living organisms as carbon and
water-based cellular forms with self-replication" as the fundamental
trait of the life process. However, this standard dictionary
definition of life does not help scientists to categorize self-
replicators like viruses, prions, proteons and artificial life. CNP
also named nanobacteria were discovered in early 1990s as about 100
nanometer-sized bacteria-like particles with unique apatite mineral-
shells around them, and found to be associated with pathological-
calcification related diseases. Although CNP have been isolated and
cultured from mammalian blood and diseased calcified tissues, and
their biomineralizing properties well established, their biological
nature and self-replicating capability have always been severely
challenged. The terms "self-replication", "self-assembly" or "self-
propagation" have been widely used for all systems including
nanomachines, crystals, computer viruses and memes. In a simple
taxonomy, all biological and non-biological "self replicators", have
been classified into "living" or "nonliving" based on the properties
of the systems and the amount of support they require to self-
replicate. To enhance our understanding about self-replicating nature
of CNP, we have investigated their growth in specific culture
conditions using conventional inverted light microscope and BioStation
IM, Nikon s latest time-lapse imaging system. Their morphological
structure was examined using scanning (SEM) and transmission (TEM)
electron microscopy. This present study, in conjunction with previous
findings of metabolic activity, antibiotic sensitivity, antibody
specificity, morphological aspects and infectivity, all concomitantly
validate CNP as living self-replicators.

NASA Center:    Johnson Space Center
Publication Date:       [2007]
Document Source:        CASI
No Digital Version Available:   Go to Tips On Ordering
Document ID:    20070030087
Price Code:     A03
Related Information:    To appear in the Nano Letters; projected release
date is Oct. 2007

Keywords:       BACTERIA NANOPARTICLES TRANSMISSION ELECTRON MICROSCOPY
SCANNING ELECTRON MICROSCOPY ORGANISMS VIRUSES METABOLISM CULTURE
TECHNIQUES DISEASES CALCIUM PHOSPHATES CRYSTALS

Accessibility:  Unclassified; Copyright; Unlimited; Publicly
available;
Updated/Added to NTRS:  2007-10-03

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