Which pair of organisms can be used for quality control in the Voges-Proskauer test?

The Voges-Proskauer (VP) test is used to detect the production of acetoin during glucose fermentation, which is an indicator of the metabolic pathway employed by certain bacteria. In this test, specific organisms are selected for quality control to ensure that the test is functioning properly and that results are reliable.

The correct pair of organisms for quality control in the VP test includes Enterobacter, which is typically positive for acetoin production, and Escherichia, which is typically recognized as a non-producer. This pairing serves to validate the test conditions. Enterobacter is a member of the Enterobacteriaceae family and usually shows a positive result in the VP test due to its ability to produce acetoin, while Escherichia (particularly Escherichia coli) usually does not produce acetoin and therefore shows a negative result.

When conducting quality control in a laboratory, ensuring that you have a range of positive and negative controls allows for a more accurate interpretation of the test results, confirming the expected activity of the organisms involved. Utilizing these specific strains as controls helps clarify any inconsistencies in results and supports proper identification of unknown samples in diagnostic settings.