Psychrophiles can be defined as the members of the kingdom Monera
thriving permanently at the lowest temperature range. Since the majority of our planet
is generally cold, psychrophiles are common within a wide range of habitats. Extensive
research in the field of genomics, transcriptomics, and proteomics revealed that
psychrophiles are endowed with several adaptive features to survive and grow in their
cold habitat. Several adaptations in different cellular entities, such as cell envelopes,
enzymes, chaperones; protein synthesis machinery, energy generating system, and
metabolic pathways have been reported. All these modifications in psychrophiles are
found to be indispensable to withstand these harsh environmental challenges. The
chapter focuses on the current state of knowledge for understanding the biodiversity
and mechanism of low-temperature adaptation of psychrophilic microorganisms.
Furthermore, the modified biomolecules in psychrophiles, mainly enzymes and
reserved materials, with distinct features, were found to be useful for several
applications including molecular biology research, bioremediation, detergent
formulations, and the food industry. The biotechnological and industrial significance of
the psychrophiles is also discussed in this chapter.