Extremophilic microbes: Diversity and perspectives

A variety of microbes inhabit extreme environments. Extreme is a relative term, which is viewed compared to what is normal for human beings. Extreme environments include high temperature, pH, pressure, salt concentration, and low temperature, pH, nutrient concentration and water availability, and also conditions having high levels of radiation, harmful heavy metals and toxic compounds (organic solvents). Culture-dependent and culture-independent (molecular) methods have been employed for understanding the diversity of microbes in these environments. Extensive global research efforts have revealed the novel diversity of extremophilic microbes. These organisms have evolved several structural and chemical adaptations, which allow them to survive and grow in extreme environments. The enzymes of these microbes, which function in extreme environments (extremozymes), have several biotechnological applications. Antibiotics, compatible solutes and other compounds obtainable from these microbes are also finding a variety of uses.