nitrifying bacterium

plural nitrifying bacteria

Definition of nitrifying bacterium

: any of various aerobic gram-negative bacteria (as of the genera Nitrosomonas, Nitrosococcus, and Nitrobacter) commonly found in soil and water and obtaining energy through the process of nitrification They are nitrifying bacteria, formerly believed to occur only in the soil and natural water systems, where they play key roles “fixing” nitrogen and making this element available to growing plants. — Bernard Dixon, The Independent (London), 16 Nov. 1992

Note: Nitrifying bacteria are sometimes classified in the paraphyletic family (Nitrobacteraceae).

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First Known Use of nitrifying bacterium

1880, in the meaning defined above

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Cite this Entry

“Nitrifying bacterium.” Dictionary, Merriam-Webster, Accessed 26 Oct. 2021.

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