Giant Viruses of the Kutch Desert

TL;DR

This study identifies DNA sequences of giant viruses in the soil of the Kutch desert, revealing their presence in an extreme, seasonally flooded, salty environment where they were previously unreported.

Contribution

It is the first to detect giant virus DNA in desert soil, expanding understanding of their ecological distribution beyond aquatic environments.

Findings

Giant virus DNA found in desert soil samples.

Presence of giant viruses in extreme, salty environments.

Challenges previous assumptions about virus habitats.

Abstract

The Kutch desert (Great Rann of Kutch, Gujarat, India) is a unique ecosystem: in the larger part of the year it is a hot, salty desert that is flooded regularly in the Indian monsoon season. In the dry season, the crystallized salt deposits form the "white desert" in large regions. The first metagenomic analysis of the soil samples of Kutch was published in 2013, and the data was deposited in the NCBI Sequence Read Archive. The sequences were analyzed at the same time phylogenetically for prokaryotes, especially for bacterial taxa. In the present work, we are searching for the DNA sequences of the recently discovered giant viruses in the soil samples of the Kutch desert. Since most giant viruses were discovered in biofilms in industrial cooling towers, ocean water and freshwater ponds, we were surprised to find their DNA sequences in the soil samples of a seasonally very hot and arid, salty environment.