Tag Archives: Clostridium diffiicle background

Clostridium difficile (C.diff.) a Spore Forming Bacteria

Types of spore forming bacteria.

To provide a background and definition of  each of them the following information is beneficial.

Bacteria are a large group of microscopic, unicellular organisms that exist either independently or as parasites. Some bacteria are capable of forming spores around themselves, which allow the organism to survive in hostile environmental conditions. Bacterial spores are made of a tough outer layer of keratin that is resistant to many chemicals, staining and heat. The spore allows the bacterium to remain dormant for years, protecting it from various traumas, including temperature differences, absence of air, water and nutrients. Spore forming bacteria cause a number of diseases, including botulism, anthrax, tetanus and acute food poisoning. (1)

Bacillus

Bacillus is a specific genus of rod-shaped bacteria that are capable of forming spores. They are sporulating, aerobic and ubiquitous in nature. Bacillus is a fairly large group with many members, including Bacillus cereus, Bacillus clausii and Bacillus halodenitrificans. Bacillus spores, also called endospores, are resistant to harsh chemical and physical conditions. This makes the bacteria able to withstand disinfectants, radiation, desiccation and heat. Bacillus are a common cause of food and medical contamination and are often difficult to eliminate.

Clostridium

Clostridium are rod-shaped, Gram-positive (bacteria that retain a violet or dark blue Gram staining due to excessive amounts of peptidoglycan in their cell walls) bacteria that are capable of producing spores. According to the Health Protecton Agency, the Clostridium genus consists of more than a hundred known species, including harmful pathogens such as Clostridium botulinum, Clostridium difficile, Clostridium perfringens, Clostridium tetani and Clostridium sordellii.

Some species of the bacteria are used commercially to produce ethanol (Clostridium thermocellum), acetone (Clostridium acetobutylicum), and to convert fatty acids to yeasts and propanediol (Clostridium diolis).

Background:

Scientists discovered C. diff in 1935, but they didn’t recognize it as the major cause of antibiotic-associated diarrhea until 1978. The rise of C. diff in the 1970s was triggered by the widespread use of the antibiotic clindamycin. Over the next 20 years, broad-spectrum antibiotics in the penicillin and cephalosporin families fueled the C. diff epidemic, and in the early years of this century, fluoroquinolone antibiotics were linked to a new and more dangerous hypervirulent strain of C. diff.

C. diff is classified as an anaerobic bacterium because it thrives in the absence of oxygen. Like its cousins, the Clostridia that cause tetanus, botulism, and gas gangrene, C. diff passes through a life cycle in which the actively dividing form transforms itself into the spore stage. Spores are inert and metabolically inactive, so they don’t cause disease. At the same time, though, spores are very tough and sturdy; they are hard to kill with disinfectants, and they shrug off even the most powerful antibiotics.

Here’s how C. diff causes trouble. Patients with C. diff shed spores into their feces. Without strict precautions, spores are inadvertently transmitted to hands, utensils, and foods, and then swallowed by someone else. The spores come to life in the second person’s GI tract, but in the best of circumstances, the normal bacteria keep C. diff in check and illness does not develop. But if the “good” GI bacteria have been knocked down by antibiotics, C. diff gets the upper hand. As C. diff multiplies and grows, it produces toxins that injure the lining of the colon, producing diarrhea, inflammation, and sometimes worse. Ordinary strains of C. diff produce two toxins, called toxins A and B, but the new, worrisome hypervirulent strains produce up to 16 times more toxin A and 23 times more toxin B. (2)

C. diff is an old bacterium,…..the CDAD epidemic is new ……..What turned a medical curiosity into a major threat? In a word, antibiotics.

Antibiotics are marvelous medications, and they are obviously here to stay. But doctors must use them wisely. That means prescribing an antibiotic only when it’s truly necessary, choosing the simplest, most narrowly focused drug that will do the job, and stopping treatment as soon as the job is done. Patients can help by resisting the temptation to demand an antibiotic for every potential infection.

When it comes to using antibiotics properly, less can be more.

Sporolactobacillus

Sporolactobacillus is a group of anaerobic, rod-shaped, spore forming bacteria that include Sporolactobacillus dextrus, Sporolactobacillus inulinus, Sporolactobacillus laevis, Sporolactobacillus terrae and Sporolactobacillus vineae. Sporolactobacillus are also known as lactic-acid bacteria for they are capable of producing the acid from fructose, sucrose, raffinose, mannose, inulin and sorbitol. Sporolactobacillus are found in the soil and often in chicken feed. According to “Fundamentals of Food Microbiology,” the spores formed by Sporolactobacillus are less resistant to heat than those formed by the Bacillus genus.

Sporosarcina

Sporosarcina are a group of round-shaped (cocci) aerobic bacteria that include Sporosarcina aquimarina, Sporosarcina globispora, Sporosarcina halophila, Sporosarcina koreensis, Sporosarcina luteola and Sporosarcina ureae. According to “Antibiotic Resistance and Production in Sporosarcina ureae,” Sporosarcina is thought to play a role in the decomposition of urea in the soil.

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Revival and Identification of Bacterial Spores in
25- to 40-Million-Year-Old Dominican Amber
Raid J. Cano* and Monica K. Borucki

A bacterial spore was revived, cultured, and identified from the abdominal contents of extinct bees preserved for 25 to 40 million years in buried Dominican amber. Rigorous surface decontamination of the amber and aseptic procedures were used during the recovery of the bacterium. Several lines of evidence indicated that the isolated bacterium was of ancient origin and not an extant contaminant. The characteristic enzymatic, biochemical, and 1 6S ribosomal DNA profiles indicated that the ancient bacterium is most closely related to extant Bacillus sphaericus.

To read the article in its entirety please click on the following link:

http://science.sciencemag.org/content/268/5213/1060.long

 

Sources:

(1)   http://Sciencing.com/types-spore-forming-bacteria-2504.html

(2) http://www.health.harvard.edu/staying-healthy/clostridium-difficile-an-intestinal-infection-on-the-rise