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Excerpts from two media reports followed by the abstract:
"AUSTRALIAN scientists claim to have conclusive proof that unusual microscopic fossils found in a four billion-year-old meteorite from Antarctica are bacterial life from Mars." http://dailytelegraph.news.com.au/st...storyid=816517 "Two Australian scientists have developed new technology to confirm claims by NASA that a meteorite from Mars found in Antarctica in 1984 contained microscopic fossils from the red planet. [...] Emeritus Professor Imre Friedmann, now at NASA Ames Research Center in California, was thrilled by the latest research which confirmed the space agency's earlier findings. 'The study of Taylor and Barry now presents evidence that the same features occur in a wide range of bacteria that live on Earth today,' Prof Friedmann said. 'The tiny structures, chains of crystals of the mineral magnetite, are comparable to animal skeletons on a microscopic scale.'" http://www.news.com.au/common/story_...E15306,00.html __________________________________________________ ____ Here's the abstract from the Journal of Microscopy: Magnetosomal matrix: ultrafine structure may template biomineralization of magnetosomes Taylor, A. P., Barry, J. C. Journal of Microscopy; Feb2004, Vol. 213 Issue 2, p180, 18p Abstract: The organic matrix surrounding bullet-shaped, cubo-octahedral, D-shaped, irregular arrowhead-shaped, and truncated hexa-octahedral magnetosomes was analysed in a variety of uncultured magnetotactic bacteria. The matrix was examined using low- (80 kV) and intermediate- (400 kV) voltage TEM. It encapsulated magnetosomes in dehydrated cells, ultraviolet-B-irradiated dehydrated cells and stained resin-embedded fixed cells, so the apparent structure of the matrix does not appear to be an artefact of specimen preparation. High-resolution images revealed lattice fringes in the matrix surrounding magnetite and greigite magnetosomes that were aligned with lattice fringes in the encapsulated magnetosomes. In all except one case, the lattice fringes had widths equal to or twice the width of the corresponding lattice fringes in the magnetosomes. The lattice fringes in the matrix were aligned with the {311}, {220}, {331}, {111} and {391} related lattice planes of magnetite and the {222} lattice plane of greigite. An unidentified material, possibly an iron hydroxide, was detected in two immature magnetosomes containing magnetite. The unidentified phase had a structure similar to that of the matrix as it contained {311}, {220} and {111} lattice fringes, which indicates that the matrix acts as a template for the spatially controlled biomineralization of the unidentified phase, which itself transforms into magnetite. The unidentified phase was thus called pre-magnetite. The presence of the magnetosomal matrix explains all of the five properties of the biosignature of the magnetosomal chain proposed previously by Friedmann et al. and supports their claim that some of the magnetite particles in the carbonate globules in the Martian meteorite ALH84001 are biogenic. Two new morphologies of magnetite magnetosomes are also reported here (i.e. tooth-shaped and hexa-octahedral magnetosomes). Tooth-shaped magnetite magnetosomes elongated in the [110] direction are reported... [ABSTRACT FROM AUTHOR] ISSN: 0022-2720 DOI: 10.1111/j.1365-2818.2004.01287.x Accession Number: 11999596 Persistent link to this record: http://search.epnet.com/direct.asp?an=11999596&db=aph Database: Academic Search Premier Ian Goddard's Journal: http://iangoddard.net/journal.htm |
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