Acinetobacter: Difference between revisions

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<h2>Genome Structure</h2>
<h2>Genome Structure</h2>
While there is much information available on the types of infections Acinetobacter causes, relatively few studies have been performed on the bacteria's genetics. Because Acinetobacters are very resistant to antibiotics and are difficult to differentiate between species when isolated from patients, learning more about their DNA will help develop better drugs to control outbreaks of the infection.
While there is much information available on the types of infections Acinetobacter causes, relatively few studies have been performed on the bacteria's genetics. Because Acinetobacters are very resistant to antibiotics and are difficult to differentiate between species when isolated from patients, learning more about their DNA will help develop better drugs to control outbreaks of the infection.
<h2>Cell Structure and Metabolism</h2><br>
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[[image:Acinetobacter2.jpg]]
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| Acinetobacter cells are short, Gram-negative rods, measuring 1.0-1.5 by 1.5-2.5 microns during growth; they often become more coccoid during the stationary phase. Cells are found in pairs or small clusters; the groups form smooth, pale colonies on solid media. All species are strictly aerobic, catalase positive, and oxidase negative; it is the last test which is most used to distinguish Acinetobacter from other infective bacteria. These bacteria can use a varied selection of organic materials as sources of carbon.
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| Cells of Acinetobacter.<br>
Image from Microbiology Department, U of New Hampshire
|}

Revision as of 15:20, 25 May 2006

Classification


Acinetobacter
Acinetobacter.jpg
Acinetobacter sp. Image from
Dennis Kunkel Microscopy, Inc.

Higher order taxa:


Bacteria; Proteobacteria; Gammaproteobacteria; Pseudomonadales; Moraxellaceae

Species:


Acinetobacter baumannii
Acinetobacter baylyi
Acinetobacter bouvetii
Acinetobacter calcoaceticus

Description and Significance

Acinetobacter is a genus of opportunistic pathogens in the proteobacteria group, species of which are distributed in widespread, diverse habitats. It has garnered media attention because of an outbreak among soldiers in Iraq who contracted the species Acinetobacter baumannii from the Iraqi soil. At least 280 people, mostly soldiers returning from the battlefield, were infected with the disease, and at least 5 (non-active-duty soldiers) died.

These bacteria can often be found as the cause of pneumonia in hospitalized patients, especially those dependent on ventilators in Intensive Care Units. The bacteria are most often contracted through the exposure of open wounds to contaminated soil. This makes it a problem during warfare (it was the second-leading cause of infection among troops during the Vietnam conflict) because of the high number of injuries caused by explosives, which can easily lead to dirtying exposed skin. In healthy humans, it is normal to have some amount of Acinetobacter on the skin surface; as many as 25% of healthy adults do in fact harbor these bacteria.

Genome Structure

While there is much information available on the types of infections Acinetobacter causes, relatively few studies have been performed on the bacteria's genetics. Because Acinetobacters are very resistant to antibiotics and are difficult to differentiate between species when isolated from patients, learning more about their DNA will help develop better drugs to control outbreaks of the infection.


Cell Structure and Metabolism


Acinetobacter2.jpg
Acinetobacter cells are short, Gram-negative rods, measuring 1.0-1.5 by 1.5-2.5 microns during growth; they often become more coccoid during the stationary phase. Cells are found in pairs or small clusters; the groups form smooth, pale colonies on solid media. All species are strictly aerobic, catalase positive, and oxidase negative; it is the last test which is most used to distinguish Acinetobacter from other infective bacteria. These bacteria can use a varied selection of organic materials as sources of carbon.
Cells of Acinetobacter.

Image from Microbiology Department, U of New Hampshire