Shewanella consists of facultatively anaerobic Gram-negative rods, most of which are found in extreme aquatic habitats where the temperature is very low and the pressure is very high.

[10] Reduction of iron and manganese through Shewanella respiration has been shown to involve extracellular electron transfer through the employment of bacterial nanowires, extensions of the outer membrane.

Scientists researching the creation of microbial fuel cells, designs that use bacteria to induce a current, have also made use of the metal reducing capabilities some species of Shewanella possess as a part of their metabolic repertoire.

[2] Members of this genus are widely distributed in aquatic habitats, from the deep sea to the shallow Antarctic Ocean.

[14] Its diverse habitats, coupled to its ability to reduce a variety of metals, makes the genus critical for the cycling of minerals.