Clostridium perfringens characteristics, morphology, habitat

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Basil Manning

Clostridium perfringens It is a gram-positive bacterium, which generally causes pathologies in humans, birds, and other mammals. It was formerly known as Clostridium welchi in honor of William Henry Welch, who discovered it in 1891 and identified it as the causative agent of gas gangrene.

This is a highly pathogenic bacterium that causes terrible damage to the body and even death, as it slowly kills the tissues it infects, leaving no opportunity for them to recover..

Clostridium perfringens seen under a microscope. Source: By Content Providers (s): CDC / Don Stalons [Public domain], via Wikimedia Commons

The virulence and effectiveness of this bacterium in the destruction of tissues is given by the different toxins that it generates and that are responsible for the terrible injuries that are caused.

The pathology most frequently associated with Clostridium perfringens It is gas gangrene, a terrible disease in which the bacteria literally kills all healthy subcutaneous and muscular tissue, causing the affected person to experience terrible pain.

The best way not to get this bacteria is through prevention. Hands should be washed before sitting down to eat and after going to the bathroom. You have to follow the sepsis measures when you have a wound, especially if it is deep or if it has been in contact with the toxin.

Every year thousands and thousands of people are infected with the Clostridium perfrinfens. For this reason, it is necessary for the population to educate itself about the symptoms and signs that this bacterium can generate, since the faster the patient is treated, the more likely they are to cope with an infection by this bacterium..

Article index

  • 1 Taxonomy
  • 2 Morphology
  • 3 General characteristics
  • 4 Pathogenesis
  • 5 Diseases
    • 5.1 Necrotic enteritis
    • 5.2 Gas gangrene
  • 6 Diagnosis
  • 7 Treatment
  • 8 Reference

Taxonomy

The taxonomic classification of the Clostridium perfringens is the next:

Domain: Bacteria

Division: Firmicutes

Class: Clostridia

Order: Clostridial

Family: Clostridiaceae

Gender: Clostridium

Species: Clostridium perfringens

Morphology

The Clostridium perfringens It is shaped like a rectangular bar, the ends of which can be rounded or straight. They are approximately 3-8 microns long by 0.4-1.2 microns wide. When viewed under the microscope, it is seen that the cells adopt three arrangements: individual, in chains or in small packages. They do not have flagella or cilia.

Its cells are surrounded by a cell wall that is made up of a thick layer of peptidoglycan, among other components. Likewise, it presents a protective capsule.

The genome of this bacterium is made up of a single circular chromosome, in which a little more than 3.5 million nitrogenous base pairs are contained..

In cultures, it forms colonies with irregular edges with a filamentous appearance, raised and translucent. In blood agar culture medium a double halo of hemolysis can be observed.

General characteristics

It is gram positive

This bacterium acquires the characteristic purple hue when subjected to the Gram stain process. Because of this it is considered gram positive.

This is due to the thick layer of peptidiglycan on its cell wall. This traps the particles of the Gram stain and retains it.

Produces spores

Bacterial cells of Clostridium perfringens they produce a single spore that is located at one of its terminal ends. During the spore formation process, toxins that are lethal to humans and a wide range of animals are synthesized..

Habitat

It is a bacterium that can be found in a large number of environments. It is part of the normal flora of the gastrointestinal tract, as well as in the skin. It is also distributed in the soil, contaminated water and dust..

Produces an enterotoxin

The Clostridium perfringens produces various toxins. Among these, the best known are:

  • Enterotoxin: main cause of food poisoning.
  • Alpha toxin: generally involved in gas gangrene in humans, as well as necrotic enteritis of chickens, cattle, and horses.
  • Beta toxin: according to various studies, this toxin can act as a neurotoxin and cause arterial constriction. It is also related to certain pathologies of the gastrointestinal tract in some mammals..
  • Epsilon toxin: It is one of the most lethal toxins produced by some bacteria of the genus. Its biological activity translates into edema. It is also dermonecrotic. Likewise, according to various studies, it has been shown that it is capable of crossing the blood-brain barrier, thereby gaining access to the brain and accumulating in it..
  • Iota toxin: it is a dermonecrotic toxin that induces gastrointestinal damage. It is also enterotoxic and cytotoxic.

It is strict anaerobic

This bacterium is a strict anaerobic organism, this means that it does not need oxygen to carry out its metabolic processes. Despite this, oxygen is not toxic to them, since they can survive in environments with a low availability of this element..

Growing conditions

The Clostridium perfringens It needs certain pH and temperature conditions to be able to develop optimally. The temperature in which it can grow is located in the range of 20 to 50 ° C, the optimum temperature being 45 ° C.

Regarding pH, this bacterium prefers environments with a certain acidity and neutrality, its ideal pH being between 5.5 and 8.

When faced with stressful environmental conditions, it produces spores. These are highly resistant to adverse conditions, such as high temperatures, extreme pH values ​​and lack of nutrients..

Metabolism

The metabolism of this bacterium is based on the fermentation process. Basically it ferments the sugars glucose, lactose and sucrose. Does not ferment mannitol.

It is indole negative

This bacterium does not have the ability to break down the indole that is part of the amino acid tryptophan structure. This is because it does not synthesize the group of enzymes known as tryptophanase, which are the ones who carry out this process..

Does not hydrolyze gelatin

The Clostridium perfringens it is not capable of gelatin liquefaction because it does not synthesize a series of enzymes known as gelatinases. This property is important because it allows, at an experimental level, to identify bacteria and differentiate them from each other..

Pathogeny

The Clostridium perfringens it is a highly pathogenic bacterium in humans. It generally causes skin infections, which are quite serious and can result in fatal outcomes..

The bacteria can enter the body through two routes: by ingestion or by inoculation at the skin level. When the bacteria is ingested, it begins to reproduce rapidly inside the body, since here it achieves the ideal environmental conditions for this.

The spores enter the bloodstream, through which they can reach various parts of the body. The spores have a predilection for muscle and intestinal tissue. Here it replicates very rapidly, causing serious tissue damage, such as necrotic lesions..

On the other hand, the bacteria can enter the body through a wound or lesion on the skin. Upon entering, it infects the surrounding muscle tissue, carrying out the fermentation process, obtaining as a product carbon dioxide in the form of gas, killing the cells and therefore the tissue.

Diseases

Necrotic enteritis

It is a disease of care, generally caused by the alpha toxin of the Clostridium perfringens. It is spread through the ingestion of undercooked chicken or meat. It is common in areas where poor nutrition and poor hygiene are common.

Symptoms

The first symptom of this infection is watery diarrhea without inflammation, accompanied by epigastric pain. In rare cases there may be fever, nausea and vomiting.

Gas gangrene

It is a life-threatening disease that affects the skin, subcutaneous, and muscle tissues. Generally, the Clostridium perfringens enters the body through an injury or surgical wound. Signs and symptoms appear suddenly and get worse quickly.

It is known as gas gangrene because the bacteria, through their metabolism, carry out fermentation and generate carbon dioxide as a product, which can be felt in the swelling of the tissue..

Symptoms

  • Jaundice (Yellow Skin).
  • Subcutaneous emphysema (air under the skin)
  • Blisters with reddish fluid
  • Tachycardia (increased heart rate)
  • High fever
  • Severe pain around the injury
  • Serosanguineous discharge with a foul odor
  • Edema around the infected lesion
  • Formation of large vesicles that coalesce and form large blisters
  • Excessive sweating

Diagnosis

For the diagnosis of this pathology, the doctor performs various tests:

  • Blood culture to verify or rule out the presence of the bacteria.
  • Cultures of the tissues or fluids draining from the lesions to check if the bacteria are present.
  • Imaging tests such as X-rays, CT scans, and MRIs may be done. In these it is common to observe gases in the tissues.

Treatment

Whenever there is a bacterial infection, the first treatment required is antibiotics, as these kill the bacteria. In the case of Clostridium perfringens, the selected antibiotics are penicillin and clindamycin.

Likewise, in the case of gas gangrene, the patient may require surgical treatment, in order to remove all the affected tissue. However, sometimes even the amputation of an affected limb (arm, leg) is necessary..

Another treatment that is contemplated is in a hyperbaric chamber, although these chambers are not available in all health care centers..

Reference

  1. Clostridium perfringens. Retrieved from: microbewiki.com
  2. Clostridium perfringens: morphology, cultural characteristics, classification and laboratory diagnosis. Retrieved from: microbesinfo.com.
  3. Cultural characteristics of Clostridium perfringens. Obtained from: microbenotes.com
  4. Gas gangrene Retrieved from: medlineplus.gov
  5. Miranda C. and Rojo, M. Clostridium perfringens. Retrieved from: org
  6. Morphology and culture characteristics of Clostridium perfrngens. Obtained from: saber.ula.ve
  7. Morris, W. and Fernández, M. (2009) Toxins of Clostridium perfingens. Argentine journal of microbiology. 41 (4).

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