Recent insights into the ecology of deep-sea microorganisms and their potential applications

The deep-sea environment is characterized by several extreme parameters such as the absence of light, cold temperature, low nutrient availability and very high hydrostatic pressure. The only deep-sea locations exhibiting different conditions of temperature and nutrients are the hydrothermal vent sites, discovered about 20 years ago. Despite the selective conditions, the biological diversity of this habitat is quite remarkable and different species of organisms are adapted to live there. On this regard, a large number of microorganisms have been isolated during the last 15 years from the deep-sea and some of these strains have clearly been shown to be barophilic more than barotolerant, exhibiting optimal growth rates at hydrostatic pressures between 200 and 600 arm. In this short review, characteristics of deep-sea ecosystems, barophilic microorganisms and potential applications are discussed, pointing out the most recent achievements and investigations in this field.