ID#: 15521
The two test tubes depicted here, contained the differential growth medium known as nitrate broth, used in the biochemical identification of organisms that are capable of reducing nitrate to nitrite, or other nitrogenous compounds via the action of the enzyme nitratase, or nitrate reductase. Inside each of these tubes, was a smaller Durham fermentation tube, which had been inverted in order to catch, and sequester any gas, as a result of the reduction of nitrate into nitrogen gas. The pink color in the tube at left indicated a positive nitrate reduction test, as well as the production of nitrogen gas.
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Content Provider(s): CDC/ R. E. Weaver, MD, PhD
Creation Date: 1971
Photo Credit:
CDC Organization
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Copyright Restrictions: None - This image is in the public domain and thus free of any copyright restrictions.