Desulfovibrio is a genus of Gram-negative sulfate-reducing bacteria. Desulfovibrio species are commonly found in aquatic environments with high levels of organic material, as well as in water-logged soils, and form major community members of extreme oligotrophic habitats such as deep granitic fractured rock aquifers. Like other sulfate-reducing bacteria, Desulfovibrio was long considered to be obligately anaerobic. This is not strictly correct: while growth may be limited, these bacteria can survive in O2-rich environments. These types of bacteria are known as aerotolerant. Some Desulfovibrio species have in recent years been shown to have bioremediation potential for toxic radionuclides such as uranium by a reductive bioaccumulation process.