Question

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In the absence of oxygen, many bacteria will carry out the process of fermentation. Carbohydrates are usually used by fermenting organisms to produce small amounts of ATP. There are many different fermentation pathways, and therefore, the end products of fermentation can be used in the identification of different types of bacteria. For example, Escherichia coli produces acids in its fermentation process, whereas Enterobacter aerogenes primarily produces a neutral end product.

Several types of tests can be performed to detect these different end products of fermentation. Commonly used fermentation tests include the O/F glucose test, carbohydrate broths with Durham tubes, the MR test, the VP test, and the citrate test. In this exercise, you will learn the procedure for conducting and analyzing several of these tests.

When conducting fermentation tests for identifying unknown bacteria, what do the tests usually detect?

multiple choice

o Different end products of fermentation

o The presence of oxidative enzymes

o Different amounts of fermentation

o Number of ATP molecules produced

Answer 1

Fermentation tests for identifying bacteria commonly detect different end products of fermentation, which help in distinguishing bacterial strains.

Step-by-step explanation:

When conducting fermentation tests to identify unknown bacteria, the tests typically detect different end products of fermentation. These tests are crucial because many bacteria have unique metabolic pathways that result in the production of specific by-products, allowing researchers to distinguish between strains.

The O/F glucose test, carbohydrate broths with Durham tubes, the MR test, the VP test, and the citrate test are common methods used to assess the type of fermentation by-products produced by bacteria, such as acids or gases. For instance, Escherichia coli (E. coli) produces acids during fermentation, while Enterobacter aerogenes yields neutral end products. These differences in fermentation outcomes are not only important in identifying bacterial species but also have applications in commercial productions, such as in the creation of solvents and pharmaceuticals.