Professor Jayant V. Narlikar

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    Janibacter hoylei sp. nov., Bacillus isronensis sp. nov. and Bacillus aryabhattai sp. nov., isolated from cryotubes used for collecting air from the upper atmosphere
    (Society for General Microbiology, 2009-05-15) Narlikar, J. V.; Shivaji, S.; Chaturvedi, Preeti; et al.
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    On searches for gravitational waves from mini-creation events by laser interferometric detectors
    (Wiley-Blackwell, 2006-02-27) Sarmah, B. P.; Banerjee, S.K.; Dhurandhar, Sanjeev; et al.
    As an alternative view to the standard big bang cosmology, the quasi-steady-state cosmology argues that the Universe was not created in a single great explosion: it did not have a beginning, nor will it ever come to an end. The creation of new matter in the Universe is a regular feature occurring through finite explosive events. Each creation event is called a mini-bang, or a mini-creation event. Gravitational waves are expected to be generated as a result of any anisotropy present in this process of creation. A mini-creation event that ejects matter in two oppositely directed jets is thus a source of gravitational waves, which can in principle be detected by laser interferometric detectors. In the present work we consider the gravitational waveforms propagated by linear jets and then estimate the response of laser interferometric detectors such as LIGO and LISA.
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    Bacillus aerius sp. nov., Bacillus aerophilus sp. nov., Bacillus stratosphericus sp. nov. and Bacillus altitudinis sp. nov., isolated from cryogenic tubes used for collecting air samples from high altitudes
    (Society for General Microbiology Journals, 2006-11-24) Shivaji, S.; Chaturvedi, Preeti; Suresh, K.; et al.
    Four novel bacterial strains were isolated from cryogenic tubes used to collect air samples at altitudes of 24, 28 and 41 km. The four strains, 24KT, 28KT, 41KF2aT and 41KF2bT, were identified as members of the genus Bacillus. Phylogenetic analysis based on 16S rRNA gene sequences indicated that three of the strains, 24KT, 28KT and 41KF2aT, are very similar to one another (>98 % sequence similarity) and show a similarity of 98–99 % with Bacillus licheniformis and 98 % with Bacillus sonorensis. DNA–DNA hybridization studies showed that strains 24KT, 28KT and 41KF2aT exhibit <70 % similarity with each other and with B. licheniformis and B. sonorensis. Differences in phenotypic and chemotaxonomic characteristics between the novel strains and B. licheniformis and B. sonorensis further confirmed that these three isolates are representatives of three separate novel species. Strain 41KF2bT showed 100 % 16S rRNA gene sequence similarity to Bacillus pumilus, but differed from its nearest phylogenetic neighbour in a number of phenotypic and chemotaxonomic characteristics and showed only 55 % DNA–DNA relatedness. Therefore, the four isolates represent four novel species for which the names Bacillus aerius sp. nov. (type strain, 24KT=MTCC 7303T=JCM 13348T), Bacillus aerophilus sp. nov. (type strain, 28KT=MTCC 7304T=JCM 13347T), Bacillus stratosphericus sp. nov. (type strain, 41KF2aT=MTCC 7305T=JCM 13349T) and Bacillus altitudinis sp. nov. (type strain, 41KF2bT=MTCC 7306T=JCM 13350T) are proposed.
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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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    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.
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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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    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.
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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.