Biogeochemical cycles recycle water and natural elements throughout the biosphere to ensure that organisms do not run out of these substances. Thiobacillus denitrificans is a specialized species of bacteria that obtains its energy from carbon dioxide and inorganic compounds such as nitrogen in its environment. It is used in bioremediation of groundwater that contains excess nitrate. How does Thiobacillus denitrificans help bioremediate groundwater?