Abstract

 Piezophiles are a sort of extremophilic organisms that nurture and survive under extreme hydrostatic pressures up to 10 MPa (1450 psi = 99 atm). The diversity of piezophilic organisms can be studied by swotting deep-sea environments that are inhabited by diverse piezophiles from all three domains of life. Information about the physiology and adaptive mechanisms of piezophiles have been obtained by the process of collection and culturing of deep-sea microorganisms. The corporeal adaptations are an absolute requisite for growth under high hydrostatic pressure in these deep-sea environments. Piezophiles possess homeoviscous adaption of lipids and fatty acids which varies with variation in the hydrostatic pressure. However, they contain docosahexaenoic acid (DHA) (22:6n-3), phosphatidylethanolamine (PE) and phosphatidylglycerol (PG) as major components, which help to acclimatize such an extreme environment. The ability of piezophiles to tolerate ultra-high pressure, extreme conditions, like low and high temperatures (2 °C– 100 °C) offers numerous applications as discussed in this chapter. This chapter mainly presents piezophilic microorganisms, including their diverse groups, their ability to raise and endure in deep-sea environments with their molecular approaches and their several applications.