Abstract

Tardigrades (water bears) are organisms, capable of surviving in very extreme conditions. These organisms are known to be ubiquitous and are mostly studied for their extremotolerant properties. Many on-going researches in other countries have shown that some of the extremotolerant properties of Tardigrades can be exploited for medical and experimental applications. But it was also observed that, these properties differed in different species of Tardigrades and also depended on their geographical location. In previous geological studies it was observed that the presence of Tardigrades in tropical region was minimal which contradicted their well-known ubiquitous nature. Therefore, in this paper, we examined the prevalence of Tardigrades in some tropical areas of Tamil Nadu and distribution of different species along with studying their different temperature toleration capacity. Thirteen out of twenty-two moss samples collected from different region of Chennai, Coimbatore and Tirunelveli, were screened positive for the presence of Tardigrades. Based on the morphological identification of claws and buccal pharyngeal apparatus, the isolated Tardigrades were distinguished as three different species. Most of the species was distinguished as Milnesium sp., and others as Murrayon sp. and Macrobiotus sp. using light and phase contrast (PC) microscopy. The phenotypically identified species were genotypically characterized as Milnesium tardigradum, Macrobiotus sapiens and Paramacrobiotus richtersi respectively using 18S rRNA sequencing. The isolated species were reared in 2% agarose plates, in order to explore their reproducing ability in fluctuating room temperature. Their survival ability to different temperatures were tested to observe their toleration limit in terms of their capacity to revive after exposure. From the above experiments, it was observed that Milnesium tardigradum displayed higher tolerance to all the different conditions exposed and was concluded that Milnesium tardigradum was highly tolerant when compared to Macrobiotus sapiens.

Keywords: Milnesium tardigradum; Paramacrobiotus richtersi; Macrobiotus sapiens; Extremotolerant; Cryptobiosis; Tun State; 18S rRNA Sequencing

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Citation

Citation: Naveen Kumar V., et al. “Study on Prevalence of Tardigrades in Tamil Nadu and Species Identification Using Pan-PCR”.Acta Scientific Medical Sciences 5.11 (2021): 42-52.

Copyright

Copyright: © 2021 Naveen Kumar V., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.