Enterobacter aerogenes
Alexa Rakusin

Shape - Coccobacillus
The shape of E. aerogenes is rod-shaped (bacillus) yet short and almost rounded or spherical (coccus).

Temperature - 30 degrees Celsius
E. aerogenes grows best at 30 degrees Celsius, or about 86 degrees Fahrenheit.

Gram Stain - Gram negative stain
This means that the E. aerogenes have a two-layer cell wall, composed of lipids and carbohydrates.
The gram stain turned the bacteria pink, indicating that the crystal purple couldn't penetrate the
second outer layer, while the Safranin could.
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Gram Negative Stain

Methyl Red - Negative
The E. aerogenes tested Methyl Red Negative, because after being incubated in glucose broth and
being added with methyl red, the substance turned bright orange. This indicated that when the bacteria
digests glucose, it produces a neutral waste product.

Motility - Positive
The E. aerogenes tested to be motile. This was discovered using a procedure, where the bacteria culture
was stabbed into a tube of motility test agar on the tip of an inoculating needle. We determined whether
they were motile or not based on whether the bacteria spread from the stab-line, or whether it only grew
within the stab-line.

Hemolysis - Gamma
The E. aerogenes tested to have Gamma hemolysis. This means that the bacteria doesn't digest Hemoglobin.

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E. aerogenes

Aerobic - Facultative
E. aerogenes is facultative, meaning that it is both aerobic and anaerobic (it can thrive in oxygenated environments
and deoxygenated environments). This was tested by placing a sample of the bacteria in a glass jar. Then a candle
was burned inside the jar, ridding it of the oxygen. Other sample were left outside of the jar, where oxygen was
available. Observations were made to determine whether it was or was not aerobic.

Antibiotic Testing - Tetracycline
With a Bauer-Kirby test, we discovered that out of Tetracycline, Penicillin, Streptomycin, and hand santizer,
Tertracycline is the most effective at killing E. aerogenes. The Tetracycline had the largest zone of inhibition,
15 mm in diameter, while Streptomycin came in second, with a 10mm ZOI in diameter. The Penicillin and
hand sanitizer both had a 0mm ZOl. Tetracycline was the most effective because this antibiotic is often used
to cure infections in the genital or urinary tract, and E. aerogenes is a gastrointestinal tract infection.
Streptomycin is a general bactericidal antibiotic, so that is why it did work on the E. aerogenes, but not
as well as the Tetracycline. Penicillin was not very effective in killing the bacteria, because it typically works
best on Gram positive bacteria, and E. aerogenes is Gram negative. Hand sanitizer was not very effective either,
because often hand sanitizers are antiseptics, used for the prevention of pathogens, instead of previous infection.

Environment - Human Gastrointestinal Tract
Enterobacter aerogenes is most often found in the gastrointestinal tract of the human. This bacteria does not actively
infect until prompted by environment causes, such as: various antibiotics,venous catheter insertions, or surgical procedures.
Some places in the gastrointestinal tract that could inhibit infectious Enterobacter aerogenes could include:
stomach, small intestine, colon, cecum, apendix, rectum, or anus. Other places this bacteria has been found
were: different waste products, hygene chemicals, and soil.

Illness -
E. aerogenes does not typically infect people with healthy immune systems. It is pathogenetic and nosocomial (caused by
treatment in hospital). Most of the bacteria infections are due to careless transfers of bacteria from surgery or consistant treatment in hospitals for patients who use venous or urethral catheters. E. aerogenes is often drug-resistant, and cannot be cured with drugs. Antiseptic surgery and watchful waiting is often necessary to cure. Septic shock and organ dysfunctions can be symptoms of an E. aerogenes infection.
Enterobacter aerogenes, Gram Negative Stain
Enterobacter aerogenes, Gram Negative Stain

Enterobacter aerogenes, Gram Negative Stain
Sources -
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0000576/
http://en.wikipedia.org/wiki/Enterobacter_aerogenes
http://en.wikipedia.org/wiki/Hand_sanitizer