Deep-marine bacteria-The Frontier alternative for heavy metals bioremediation

Metals are an intrinsic part of the earth’s crust. Rapid industrialization leads to an enormous amount of wastes accumulating which requires special treatment. Metals like Cu, As, Sb, Cd, Hg, and Zn possess a serious threat to the environment which are needed to be removed. Wastes from the sewage sludge, power plant, mining, and metal refining industries contain a substantial amount of toxic heavy metals. Microbes present in nature can adapt to extreme conditions as well as perform various physiological activities. Deep-marine environments are the most adverse environments owing to their varying nature of pH, temperature, currents precipitation regimes, salinity, sea surface temperature, and wind pattern. Microbes present in the deep marine are more suitable to adapt the adverse conditions because of the constant variation of environmental conditions. The major advantage of microbes from deep marine for bioremediation in situ is the direct use in any adverse conditions. Therefore, the bacteria from the deep-marine environments are utilized in bioremediations of metals and other recalcitrant compounds. There are many strategies by which deep-marine bacteria resist high concentrations of metals including extracellular sequestration, precipitation, reduction, efflux mechanisms, biosorption, altered permeability, intracellular bioaccumulation, etc. The unique characteristics of deep-marine bacteria proved to be an ideal tool for bioremediation of metals from contaminated environmental sites. This chapter emphasizes the utilization of deep-marine bacteria for bioremediation as well as understanding the mechanism behind acquiring the characteristic feature of adaptive responses.