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Author: search.filters.author.Wainwright, M.

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    Studies on bacteria-like particles sampled from the stratosphere
    (Springer, 2004-07-28) Wainwright, M.; Weber, P. K.; Smith, J. B.; et al.
    Bacteria-like particles recovered from the stratosphere and deposited on cellulose acetate membranes have been analysed to confirm their bacterial nature. One particle appeared to be attached to an inorganic 2 particle apparently by mucoid material typically produced by bacteria. A filamentous structure, morphologically similar to a fungal hypha, was also observed. EDS analysis showed that the particles were all non-mineral and therefore could be biological in nature. However, the composition several clumps of nanobacteria-sized particles were found, by SIMS analysis, to be inconsistent with that of bacteria. The results show that it is dangerous to assume that bacteria-like particles seen under scanning electron microscopy are necessarily bacteria.
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    Confirmation of the presence of viable but non-culturable bacteria in the stratosphere
    (Cambridge University Press, 2004-01-05) Wainwright, M.; Wickramasinghe, N. C.; Narlikar, J. V.; et al.
    The presence of viable, but non-cultureable, bacteria on membranes through which stratospheric air samples were passed has been confirmed using viable fluorescent staining.
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    Are these stratospheric nanoparticles bacteria?
    (2004-03-27) Wainwright, M.; Wickramasinghe, N. C.; Narlikar, J. V.; et al.
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    Progress towards the vindication of panspermia
    (Kluwer Academic Publishers, 2002-04-29) Narlikar, J. V.; Wickramasinghe, N. C.; Wainwright, M.; et al.
    Theories of panspermia are rapidly coming into vogue, with the possibility of the transfer of viable bacterial cells from one planetary abode to another being generally accepted as inevitable. The panspermia models of Hoyle and Wickramasinghe require the transfer of viable bacterial cells from interstellar dust to comets and back into interplanetary and interstellar space. In such a cycle a viable fraction of as little as 10−18 at the inception of a newly formed comet/planet system suffices for cometary panspermia to dominate over competing processes for the origin and transfer of life. The well-attested survival attributes of microbes under extreme conditions, which have recently been discovered, gives credence to the panspermia hypothesis. The prediction of the theory that comets bring microbes onto the Earth at the present time is testable if aseptic collections of stratospheric air above the tropopause can be obtained. We describe a recent collection of this kind and report microbiological analysis that shows the existence of viable cells at 41 km, falling to Earth at the rate of a few tonnes per day over the entire globe. Some of these cells have been cultured in the laboratory and found to include microorganisms that are not too different from related species on the Earth. This is in fact what the Hoyle-Wickramasinghe theory predicts. The weight of evidence goes against the more conservative explanation that organisms are being lofted to the high atmosphere from the ground.
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    Detection of microorganisms at high altitudes
    (Indian Academy of Sciences, 2003-07-10) Narlikar, J. V.; Wickramasinghe, N. C.; Wainwright, M.; et al.
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    Did silicon aid in the establishment of the first bacterium?
    (Cambridge University Press, 2003-07-01) Narlikar, J. V.; Wainwright, M.; Al-Wajeeh, K.; et al.
    Silicic acid increased numbers of both aerobic and facultatively anaerobic bacteria in ultrapure water incubated under strict oligotrophic conditions ; soil extracts acted as the bacterial inoculum. The results are discussed in relation to the possibility that silicic acid, produced by the hydrolysis of silicates on the early Earth, could have stimulated the growth of the first bacterium, thereby allowing it to become established in the then prevailing conditions (presumed to be oligotrophic).
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    Microorganisms cultured from stratospheric air samples obtained at 41 km
    (Elsevier Science Publishers, 2002-12-03) Wainwright, M.; Wickramasinghe, N. C.; Narlikar, J. V.; et al.
    Samples of air removed from the stratosphere, at an altitude of 41 km, were previously found to contain viable, but non-cultureable bacteria (cocci and rods). Here, we describe experiments aimed at growing these, together with any other organisms, present in these samples. Two bacteria (Bacillus simplex and Staphylococcus pasteuri) and a single fungus, Engyodontium album (Limber) de Hoog were isolated from the samples. Although the possibility of contamination can never be ruled out when space-derived samples are studied on earth, we are confident that the organisms originated from the stratosphere. Possible mechanisms by which these organisms could have attained such a height are discussed