Submitted to: Bergey's Manual of Systematic Bacteriology
Publication Type: Book / Chapter
Publication Acceptance Date: January 28, 2008
Publication Date: January 1, 2012
Citation: Anderson, R.C., Stanton, T.B. 2012. Genus V. Denitrobacterium. In: Goodfellow, M., Kampfer, P., Busse, H., Trujillo, M., Suzuki, K., Ludwig, W., Whitman, W., editors. Bergey's Manual of Systematic Bacteriology. 2nd edition. New York, NY: Springer. p. 1988-1990. Interpretive Summary: This chapter describes for microbiologists a specific group of bacteria known as Denitrobacterium. Bacteria belonging to Denitrobacterium were initially isolated from the gastrointestinal contents of cattle. The cells of this bacterium are rod shaped and generally measure 0.5 to 1.0 x 1.0 to 1.5 um. The bacterium does not produce spores and is non-motile. A novel feature of this bacterium is that it obtains energy for growth exclusively via anaerobic respiration. The bacterium respires on chemical compounds like 3-nitropropanol, 2-nitropropanol, 3-nitropropionate, nitroethanol, nitroethane, 1-nitropropane, 2-nitrobutane, dimethyl sulfoxide, trimethyl amine-oxide and sometimes nitrate much like we respire on oxygen. The bacterium grows well in bacteriological culture media containing clarified rumen fluid, peptone and one of the above chemicals. Unlike most other anaerobic bacteria, Denitrobacterium does not use a wide variety of sugars or other chemicals such as sulfate, sulfite, fumarate, azide, chlorate, perchlorate, 2-nitrobenzene, and nitrite to support growth. Little if any acid is produced during growth in its anaerobic medium and gelatin is not hydrolyzed. Moreover, indole and H2S are not produced. According to DNA analysis, Denitrobacterium belongs to the family Actinobacteria. Because Denitrobacterium can degrade 3-nitropropanol and 3-nitropropionic acid, which are toxic constituents of many grasses on western American pastures, this bacterium plays a role in helping cattle and sheep safely eat these forages. The description of this bacterium in this chapter will help microbiologists and other researchers differentiate this bacterium from other known bacteria.
Technical Abstract: This chapter describes the Genus Denitrobacterium. The cells of this bacterium are rod shaped and generally measure 0.5 to 1.0 x 1.0 to 1.5 um. The bacterium is non-sporulating and non-motile. The bacterium is nonfermentative but rather obtains energy for growth exclusively via anaerobic respiration. Growth is supported in anaerobic media containing clarified rumen fluid, peptone and a suitable electron acceptor. 3-Nitropropanol, 2-nitropropanol, 3-nitropropionate, nitroethanol, nitroethane, 1-nitropropane, 2-nitrobutane, dimethyl sulfoxide, trimethyl amine-oxide and sometimes nitrate may be used as electron acceptors. Sulfate, sulfite, fumarate, azide, chlorate, perchlorate, 2-nitrobenzene, and nitrite do not support growth. Little if any acid is produced during growth in medium with hydrogen or formate as electron donor. Hydrogen, formate, and (DL)-lactate can be used as electron donor. Acetate is predominant fatty acid produced during growth in medium containing lactate. Gelatin is not hydrolyzed, indole and H2S are not produced. Palmitic acid (C14:0) is the predominant cellular fatty acid of cells grown in modified brain heart infusion medium, although an abundance of other straight and branched chain fatty acids, aldehydes, and dimethyl acetals are present. Cells contain a c-type cytochrome. Isolated from bovine rumen contents. A single species of Denitrobacterium, D. detoxificans, has been characterized. The mol% G+C content of the DNA is 56 to 61% (Tm). According to 16S rRNA sequence analysis, Denitrobacterium belongs to the Actinobacteria. The type species is Denitrobacterium detoxificans.