Influence of pressure on microbial growth

Pressure is generally defined as the force acting per unit area. It  is one of the major physical factor that affects the growth of microorganisms. Microorganisms that grow on the land or on the surface of water are generally exposed to the pressure of 1 atmosphere. On the basis of pressure, microorganisms are classified into two types:

Barotolerant: They are not affected by increase in pressure. They require standard atmospheric pressure for their growth but they can also grow at high pressure.

Barophilic: They are also called piezophile, which means pressure-lover. They grow best at high pressure like deep-sea bacteria and archaea. Example includes Halomonas salaria, Photobacterium profundum, Methanococcus jannaschii, Shewanella benthica etc. They play an important role in nutrient recycling in the deep sea.