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Name: Class: Date:

ENTEROPLURI-TEST OBJECTIVES

To learn the purpose of multi-test systems. To perform the EnteroPluri-Test and analyze the results.

INTRODUCTION

It may require many selective and differential media and tests to give enough information to identify a species of bacteria. Modern technology makes this process faster with multi-test systems that allow you to inoculate a series of differential media at the same time in one tube. EnteroPluri-Test is a multi-test system used to identify enteric (intestinal) bacteria. Before using EnteroPluri-Test, a sample must be Gram stained to ensure that it is Gram-negative. For our experiment, you may assume this Gram stain step has already been done.

The EnteroPluri tube has 12 chambers, each of which tests for one or more biochemical

reactions. Table 1 below lists the biochemical reactions for each chamber and the positive and negative results for that reaction.

Table 1. Biochemical tests for each chamber of the EnteroPluri tube.

Source: Liofilchem EnterPluri-Test Codebook.

http://bd.com/ds/technicalCenter/inserts/L010569%2802%29.pdf

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DIRECTIONS Day 1

1. Obtain a streak plate with an unknown bacteria species. Be sure to note the number of your unknown.

2. Obtain an EnteroPluri tube. Label. 3. Place a paper towel on your benchtop and soak it with disinfectant. 4. Remove the caps from both ends of your EnteroPluri tube and place them, open-end

down, on the paper towel. This will keep the caps relatively sterile. 5. Holding the EnteroPluri tube like a pencil, use the pointed end of the wire to scrape up

one colony of the unknown bacteria from the streak plate. See Figure 1.

Figure 1. Inoculation of EnteroPluri tube with bacterial colony.

Source: Liofilchem EnterPluri-Test brochure.

http://www.liofilchem.net/en/mov_enteropluritest.php

6. Grasp the looped end of the wire and gently twist and pull the wire until the pointed end reaches the last chamber of the EnteroPluri tube. DO NOT REMOVE THE WIRE COMPLETELY.

7. Push the wire back into the EnteroPluri tube until you can see the pointed tip in the citrate chamber. Break off the wire remaining outside the tube by bending at the notch on the wire.

8. Use the broken end of wire to puncture the eight air inlets on the one side of the EnterPluri tube. (Ask instructor if you cannot see these air inlets.) Be sure to dispose of the broken wire in the sharps container.

9. Replace the caps on the ends of EnteroPluri tube. 10. Place EnteroPluri tube in the incubator, flat side down.

Day 2

1. Retrieve your EnteroPluri tube culture and obtain an EnteroPluri-Test results chart. 2. Observe your tube and record the results of all chambers except the indole and VP on

the results chart.

3. Use a sterile toothpick to pierce H2S/Indole chamber and add a few drops of Kouvac’s reagent to see the indole result. Record on the results chart. Be careful to avoid spilling the Kouvac’s reagent.

4. If VP reagents are available, use a sterile toothpick to pierce the VP chamber and add VP reagent to see the VP result. Record on the results chart. Be careful to avoid spilling the VP reagent. If no VP reagent is available, the test may be scored as negative.

5. For each positive result, circle the number below that result on the chart. Add the circled numbers in each section to generate the five-digit code. Tape or staple your results chart in the designated space below.

6. Look up the five-digit code in the EnteroPluri-Test codebook. Write any species identified with that code in the designated space below. There may be more than one listed.

Results chart: Species identified: