Adaptations, diversity, and biotechnological potential of thermophilic microorganisms: exploring culture-dependent and culture-independent approaches in extreme environments.

Thermophilic prokaryotes exhibit remarkable adaptations at both physiological and molecular levels, which enables them to survive in elevated-temperature environments (35-113 °C). This review consolidates the current findings on membrane, genomic and proteomic adaptations of thermophiles, including presence of ether-linked lipids, branched-chain fatty, saturated long-chain hydrocarbons, reverse gyrase-mediated DNA supercoiling, and group II chaperonins. Although culture-independent approaches, such as metagenomics and next-generation sequencing (NGS) techniques, have expanded our understanding of thermophilic microbial diversity, which is limited by traditional culture-dependent approaches. However, these findings are largely based on the genomic predictions rather than direct experimental evidence. Therefore, the culture-dependent methods are crucial for isolating and characterizing thermophiles for both genetic and functional studies. India's geothermal spring ecosystems serve as natural laboratories for studying diverse thermophilic communities, offering a valuable resource for both ecological and biotechnological exploration. Enzymes derived from thermophiles, known as thermophiles exhibit remarkable thermal stability and catalytic efficiency at temperatures ranging from 60 to 125 °C, with applications in biofuels, pharmaceuticals, and industrial bioprocessing. Integration of both culture-based and metagenomic approach provide a comprehensive framework for understanding the thermophile biology and reveals their biotechnological potential.