How would the IMVic tests differentiate E. coli from Enterobacter aerogenes?

What lab test for E aerogenes?

For Enterobacter aerogenes, common lab tests include culture and sensitivity testing on samples such as blood, urine, or sputum to identify the bacteria and determine its susceptibility to antibiotics. Molecular tests like polymerase chain reaction (PCR) can also be used for rapid and accurate detection of E. aerogenes DNA in clinical specimens. Biochemical tests, such as indole, citrate utilization, or urease tests, can help further differentiate Enterobacter species in the lab.

How IMViC tests differentiate Escherichia coli from Enterobacter aerogenes?

Indol Test ( Kovac's Reagent): E.a. = negative = yellow/gold ring at meniscus; as for E.c. = positive = red ring at meniscus (immediate change). Methyl Red Test (Methyl Red Reagent): E.a. = negative = yellow = pH > 7.0; as for E.c. = red color = pH < 5 (immediate change). Vogues-Proskauer Test (Napthol + KOH Reagent): E.a. = positive = reddish color (not immediate change); as for E.c. = negative = brown/yellow (straw color). Citrate (Bromothymol Blue Reagent - alkaline pH): E.a. = positive = blue color + growth; as for E.c. = negative = green color.

Is enterobacter aerogenes lipase negative?

Yes it is. You can easily check it out yourself by using a tributyrine based agar. If Enterobacter aerogenes builds a lipase action enzyme, the surrounding of your colonies will be much clearer. If you have any other questions, I suggest you the Bergey's manual of systematic bacteriology.

Why e aerogenes h2s positive?

Enterobacter aerogenes is H2S positive because it has the ability to produce hydrogen sulfide gas as a byproduct of its metabolism. This characteristic is part of the organism's biochemical profile and can be used in laboratory identification tests.

Does enterobacter aerogenes produce red and white colonies in nutrient agar?

Yes, Enterobacter aerogenes can produce both red and white colonies on nutrient agar. The color of the colonies can vary based on the potential presence of pigments produced by the bacteria under different growing conditions. Additional tests may be needed for accurate identification.

What test will show you the difference between Proteus vulgaris and Morganella morganii?

alpha-glucosidase test: using 5-bromo-4-chloro-3-indolyl-alpha-D-glucopyranoside (included in chromogenic media), but not using alpha-methyl-glucoside fermentation. Cronobacter (E. sakazakii) are positive for this test and E. aerogenes are negative.

Discuss the medical significance of the IMViC series of tests?

The IMViC series of tests provides an identification of the principal groups of Enterobacteriaceae that cause intestinal infections, by using the biochemical properties and their enzymatic reactions to specific substrates

What is the gram stain of enterobacter aerogenes?

Enterobacter aerogenes is a Gram negative rod-shaped bacterium in the same family as Esherichia coli. It can grow on many of the same selective media as Esherichia coli, including: MacConkey Agar, EMB agar and Lauryl-Tryptose broth. E. aerogenes ferments lactose, producing acid and gas like Esherichia coli and is classified as an example of coliform bacteria. There are several significant differrences between E. aerogenes and E. coli: 1) Most strains of E.coli are able to grow and produce acid from lactose in a medium such as lauryl tryptose broth or brilliant green bile broth at 44.5 degrees C. while most strains of E. aerogenes do not grow well at that temperature, E. aerogenes grows better at temperatures betwee 34 - 40 degrees C. 2) E. aerogenes carries out 2,3-butanediol fermentation and thus give a positive test in the Voges-Proskauer test while E. coli is negative. 3) E. coli is positive in the methyl red test while E. aerogenes is usually, but not always, negative (this is not the best test to rely on). 4) E.coli is positive for the indole test while E. aerogenes is negative, this is a very reliable test. 5) E. aerogenes can grow on Simmon's citrate agar while E. coli does not. You can distinguish between E. aerogenes and bacteria in the Proteus and Salmonella genera by using the hydrogen sulfide test, using either Kligler's iron agar or triple sugar iron agar. Most Proteus and Salmonella strains produce hydrogen sulfide and make a black precipitate but E. aerogenes does not. There are a lot of similarities between Enterobacter aerogenes and Klebsiella pneumonia. The urease test is one of the few tests that distinguishes E. aerogenes from K. pneumonia. Enterobacter aerogenes is a Gram negative rod-shaped bacterium in the same family as Esherichia coli. It can grow on many of the same selective media as Esherichia coli, including: MacConkey Agar, EMB agar and Lauryl-Tryptose broth. E. aerogenes ferments lactose, producing acid and gas like Esherichia coli and is classified as an example of coliform bacteria. There are several significant differrences between E. aerogenes and E. coli: 1) Most strains of E.coli are able to grow and produce acid from lactose in a medium such as lauryl tryptose broth or brilliant green bile broth at 44.5 degrees C. while most strains of E. aerogenes do not grow well at that temperature, E. aerogenes grows better at temperatures between 34 - 40 degrees C. 2) E. aerogenes carries out 2,3-butanediol fermentation and thus give a positive test in the Voges-Proskauer test while E. coli is negative. 3) E. coli is positive in the methyl red test while E. aerogenes is usually, but not always, negative (this is not the best test to rely on). 4) E.coli is positive for the indole test while E. aerogenes is negative, this is a very reliable test. 5) E. aerogenes can grow on Simmon's citrate agar while E. coli does not. You can distinguish between E. aerogenes and bacteria in the Proteus and Salmonella genera by using the hydrogen sulfide test, using either Kligler's iron agar or triple sugar iron agar. Most Proteus and Salmonella strains produce hydrogen sulfide and make a black precipitate but E. aerogenes does not. There are a lot of similarities between Enterobacter aerogenes and Klebsiella pneumonia. The urease test is one of the few tests that distinguishes E. aerogenes from K. pneumonia. Klebsiella is positive for urease production while Enterobacter is negative.

IMVIC tests for streptococci?

IMViC tests (indole, methyl red, Voges-Proskauer, citrate utilization) are typically used for the identification of enteric bacteria, not for streptococci. Streptococci are usually identified using other methods such as hemolysis patterns, catalase, and Lancefield grouping based on cell wall antigens.

Bacteria voges proskauer positive and methyl red positive?

The bacteria is likely to be Enterobacter or Serratia, as they are known to be Voges-Proskauer positive and Methyl Red positive. These two tests are commonly used to differentiate between different species of bacteria based on their metabolic pathways. Enterobacter and Serratia are both members of the Enterobacteriaceae family and typically show these characteristics.

Does Enterobacter cloacae produce H2S?

Yes, Enterobacter cloacae is capable of producing hydrogen sulfide (H2S) as part of its metabolic activity, which can be detected through biochemical tests such as Triple Sugar Iron (TSI) agar.

How is quality control performed in IMViC?

Quality control in IMViC (Indole, Methyl Red, Voges-Proskauer, and Citrate tests) is performed by using control strains that provide known results for each test. These control organisms ensure the reliability of the test results and help identify any inconsistencies in the testing procedure. Regular calibration of equipment and adherence to standardized protocols further support the accuracy and validity of the IMViC tests. Additionally, periodic reviews and documentation of results contribute to maintaining quality assurance in the microbiological analysis.