To install click the Add extension button. That's it.

The source code for the WIKI 2 extension is being checked by specialists of the Mozilla Foundation, Google, and Apple. You could also do it yourself at any point in time.

4,5
Kelly Slayton
Congratulations on this excellent venture… what a great idea!
Alexander Grigorievskiy
I use WIKI 2 every day and almost forgot how the original Wikipedia looks like.
Live Statistics
English Articles
Improved in 24 Hours
Added in 24 Hours
What we do. Every page goes through several hundred of perfecting techniques; in live mode. Quite the same Wikipedia. Just better.
.
Leo
Newton
Brights
Milds

Voges–Proskauer test

From Wikipedia, the free encyclopedia

Two bacterial broth cultures, showing a positive result (left side) and a negative result (right side) for the VP test.

Voges–Proskauer /ˈfɡəsˈprɒsk.ər/ or VP is a test used to detect acetoin in a bacterial broth culture. The test is performed by adding alpha-naphthol and potassium hydroxide to the Voges-Proskauer broth, which is a glucose-phosphate broth that has been inoculated with bacteria. A cherry red color indicates a positive result, while a yellow-brown color indicates a negative result.[1]

The test depends on the digestion of glucose to acetylmethylcarbinol. In the presence of oxygen and strong base, the acetylmethylcarbinol is oxidized to diacetyl, which then reacts with guanidine compounds commonly found in the peptone medium of the broth. Alpha-naphthol acts as a color enhancer, but the color change to red can occur without it.

Procedure: First, add the alpha-naphthol; then, add the potassium hydroxide. A reversal in the order of the reagents being added may result in a weak-positive or false-negative reaction.

VP is one of the four tests of the IMViC series, which tests for evidence of an enteric bacterium. The other three tests include: the indole test [I], the methyl red test [M], and the citrate test [C].[2]

VP positive organisms include Enterobacter, Klebsiella, Serratia marcescens, Hafnia alvei, Vibrio cholerae biotype El Tor, and Vibrio alginolyticus.[3]

VP negative organisms include Citrobacter sp., Shigella, Yersinia, Edwardsiella, Salmonella, Vibrio furnissii, Vibrio fluvialis, Vibrio vulnificus, and Vibrio parahaemolyticus.[3]

YouTube Encyclopedic

  • 1/3
    Views:
    31 855
    2 170
    85 657
  • Microbiology: Voges-Proskauer Test
  • Voges Proskauer (VP) test: 2 Minutes Microbiology: Dr. Tanmay Mehta
  • Voges-Proskauer Test - Amrita University

Transcription

History

The reaction was developed by Daniel Wilhelm Otto Voges and Bernhard Proskauer, German bacteriologists in 1898 at the Institute for Infectious Diseases.

References

  1. ^ MacFaddin, J. F. 1980. Biochemical Tests for Identification of Medical Bacteria, 2nd ed. Williams and Wilkins, Baltimore
  2. ^ Bachoon, Dave S., and Wendy A. Dustman. Microbiology Laboratory Manual. Ed. Michael Stranz. Mason, OH: Cengage Learning, 2008. Exercise 15, "Normal Flora of the Intestinal Tract" Print.
  3. ^ a b Bergey's Manual of Systematic Bacteriology, Vol. 1. Baltimore, Williams and Wilkins, 1984.

External links


This page was last edited on 3 January 2023, at 23:03
Basis of this page is in Wikipedia. Text is available under the CC BY-SA 3.0 Unported License. Non-text media are available under their specified licenses. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc. WIKI 2 is an independent company and has no affiliation with Wikimedia Foundation.