Research Papers (JVN)
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Item Functions and possible provenance of primordial proteins(American Chemical Society, 2004-11-17) Sommer, Andrei P.; Miyake, Norimune; Wickramasinghe, N. C.; et al.Nanobacteria or living nanovesicles are of great interest to the scientific community because of their dual nature: on the one hand, they appear as primal biosystems originating life; on the other hand, they can cause severe diseases. Their survival as well as their pathogenic potential is apparently linked to a self-synthesized protein-based slime, rich in calcium and phosphate (when available). Here, we provide challenging evidence for the occurrence of nanobacteria in the stratosphere, reflecting a possibly primordial provenance of the slime. An analysis of the slime’s biological functions may lead to novel strategies suitable to block adhesion modalities in modern bacterial populations.Item 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.Item Are these stratospheric nanoparticles bacteria?(2004-03-27) Wainwright, M.; Wickramasinghe, N. C.; Narlikar, J. V.; et al.Item Balloon experiment to detect microorganisms in the outer space(Kluwer Academic Publishers, 2003-03-30) Narlikar, J. V.; Lloyd, David; Wickramasinghe, N. C.; et al.The results of biological studies of a cryosampler flown with a balloon, in which air samples were collected at altitudes ranging from 20 to 41 km, well above the Tropopause over Hyderabad, are described. In the analysis carried out in Cardiff, voltage-sensitive dyes that could detect the presence of viable cells were used on these air-amples. Clumps of viable cells were found to be present in samples collected at all the altitudes. The images obtained from electron microscopy are consistent with the above finding. Reference is also made to a not her paper presented at this conference describing the identification of bacterial species in the sample carried out in Sheffield. Counter arguments are discussed against the criticism that the detected cells and microorganisms (in the samples collected above the local tropopause at 16 km) are due toterrestrial contamination.Item 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.Item Detection of microorganisms at high altitudes(Indian Academy of Sciences, 2003-07-10) Narlikar, J. V.; Wickramasinghe, N. C.; Wainwright, M.; et al.Item 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 discussedItem Detection of living cells in stratospheric samples(SPIE Conference, 2002-04-14) Narlikar, J. V.; Harris, Melanie J.; Wickramasinghe, N. C.; et al.Air samples collected aseptically over tropical India at various stratospheric altitudes ranging from 20 to 41 km using cryosampler assemblies carried on balloons flown from Hyderabad have shown evidence of living microbial cells. Unambiguous evidence of living cells came from examining micropore filters on which the samples were recovered with the use of voltage sensitive lipophilic dyes that could detect the presence of active cells. Clumps of viable cells were found at all altitudes using this technique, and this conclusion was found to be consistent with images obtained from electron microscopy. Since the 41 km sample was collected well above the local tropopause, aprimafacie case for a space incidence of these microoraganisms is established. Further work on culturing, PCR analysis and isotopic analysis is in progress.Item Possible detection of extraterrestrial life in stratospheric samples(Tata Institute of Fundamental Research, 2002-03-30) Narlikar, J. V.; Lloyd, David; Wickramasinghe, N. C.; et al.Direct evidence for living cells in the air samples collected aseptically over Hyderabad (India) at various altitudes is presented. In the preliminary experiment, samples collected from altitudes of 10 to 36 Km yielded six identical bacterial colonies with phenotypic characteristics distinct from hitherto described Pseu-domonas stutzeri, a terrestrial bacterium. Since in this earlier experiment the air-samples were collected over a long range of altitude (including the ones at low altitudes), it was not possible to completely rule out terrestrial contamination. On the other hand in the current experiment, the samples were collected at altitudes ranging from 20 to 41 Km, well above tho Tropopause over Hyderabad. Voltage-sensitive dyes that could detect the presence of viable cells were used on these air-samples. Clumps of viable cells were present in samples collected at all the altitudes. The images obtained from electron microscopy are consistent with the above picture. Arguments are advanced against the detected cells (in the samples collected in the present experiment above the local tropopause at 16 Kin) being due to terrestrial contamination.Item Radiation of microwaves and infrared by slender graphite needles(Kluwer Academic Publishers, 1984-03-22) Hoyle, F.; Narlikar, J. V.; Wickramasinghe, N. C.It has become clear from sources observed by IRAS that there are many examples which attain maximum emission per unit (frequency) bandwidth longward of 100 μm. Here, we show that a large emissivity at such long wavelengths can be obtained by needle-shaped particles of free carbon. Indeed for needles with a sufficiently high ratio of length to diameter the large emissivity extends from the infrared through the whole microwave region of the spectrum.