Clostridium, botulinum

Nitrates are found in fairly high concentrations in beets, spinach, kale, coUards, eggplant, celery, and lettuce. AdditionaHy, nitrates and nitrites are commonly used in the curing solutions of bacon, ham, and other cured meats. In cured meats, nitrates and nitrites control the growth of microorganisms, particularly Clostridium botulinum, and also serve as color preservatives. 

Small GTPases of the Rho family are ADP-ribosylated (e.g., at Asn4l of RhoA) and inactivated by C3-like toxins from Clostridium botulinum, Clostridium limosum, and Staphylococcus aureus. These proteins have a molecular mass of 23-30 kDa and consist only of the enzyme domain. Specific inhibition of Rho functions (Rho but not Rac or Cdc42 are targets) is the reason why C3 is widely used as a pharmacological tool [2]. 

Botulism is a disease caused by ingestion of foods contaminated with Clostridium botulinum (food-borne botulism) or, very rarely, by wound infection (wound botulism) or colonization of the intestinal tract with Clostridium botulinum (infant botulism). The toxins block the release of acetylcholine. Botulism is characterized by generalized muscular weakness, which first affects eye and throat muscles and later extends to all skeletal muscles. Flaccid paralysis can lead to respiratory failure. 

The most ingenious exocytosis toxins, however, come from the anaerobic bacteria Clostridium botulinum and Clostridium tetani. The former produces the seven botulinum neurotoxins (BoNTs) A-G the latter produces tetanus neurotoxin (TeNT). All eight toxins consist of a heavy (H) chain and a light (L) chain that are associated by an interchain S-S bond. The L-chains enter the cytosol of axon terminals. Importantly, BoNT L-chains mainly enter peripheral cholinergic terminals, whereas the TeNT L-chain mainly enters cerebral and spinal cord GABAergic and glycinergic terminals. The L-chains are the active domains of the toxins. They are zinc-endopeptidases and specifically split the three core proteins of exocytosis, i.e. the SNAREs (Fig. 1 inset). Each ofthe eight toxins splits a... 

Clonal Selection Clostridial Neurotoxins Clostridium Botulinum Toxin Clotting CNTF... 

The mechanism whereby the bacteria produce the disease with its attendant symptoms is often due to the cells ability to produce specific poisons, toxins or aggressins (Chapter 14). Many of these are tissue-destroying enzymes which can damage the cellular structure ofthe body or destroy red blood cells. Others (neurotoxins) are highly specific poisons ofthe central nervous system, for example the toxin produced by Clostridium botulinum is, weight for weight, one ofthe most poisonous substances known. 

There are reports of the benefits of botulinum toxin in the treatment of cerebral palsy in children. The toxin, produced by Clostridium botulinum, is a powerful and deadly poison, but is also an effective muscle relaxant. It is not licensed for use as such in the UK but is undergoing clinical trials. Current evidence suggests that repeat injections are necessary some 4-6 months after the first. 

Similar to catechins, several studies have reported that proanthocyanidins exhibit a more or less pronoimced antibacterial activity. Chimg et al. [76] reported that proanthocyanidins determine the growth inhibition of strains of Aeromonas spp.. Bacillus spp., Clostridium botulinum, Clostridium per-fringens, Enterobacter spp., Klebsiella spp., Proteus spp.. Pseudomonas spp.. Shigella spp., S. aureus. Streptococcus spp., and Vibrio spp. 

Clostridium botulinum 18-24 Canned fruits, vegetables, meats, honey, salsa, relish Weeks Acute Gl symptoms followed by symmetric, descending, flaccid paralysis death is possible Supportive (including mechanical ventilation) trivalent antitoxin... 

Bacteria not only attack teeth but can also make people extremely sick. Therefore, canned food must be specially prepared to prevent the growth of bacteria. This is usually done by boiling or steaming. People who can their own food at home, however, do not have the sophisticated machines that food-canning manufacturers have. Even so, there are other methods that home canners can use to preserve their own food and keep their families safe. For example, high heat can be used to kill the bacteria Clostridium botulinum, which causes one deadly form of food poisoning called botulism. Acidic conditions will also kill C. botulinum. Because the bacteria cannot survive at a pH below 4.5, very acidic foods such as tomatoes, pears, and peaches are safe for home canning. 

Bacteria, viruses, and rickettsiae have similar symptom progressions in that exposure is followed by a period of reproductive growth (often nonsympto-matic) in the body. As their numbers increase, they often eventually overcome the immune system. Many produce toxins that interfere with bodily functions. Purified toxins such as botulinum toxin (produced by the Clostridium botulinum bacteria) act in a similar manner to chemical agents since, as complex chemical compounds, they do not reproduce but immediately interfere with bodily functions. However, most toxins are not absorbed through the skin, as... 

Clostridium botulinum Norwalk like Giardia lamblia... 

Delayed-action paralytic neurotoxins that block the release of acetylcholine causing a symmetric, descending flaccid paralysis of motor and autonomic nerves. Paralysis always begins with the cranial nerves. Toxins are obtained from an anaerobic bacteria (Clostridium botulinum). Toxin A is a white powder or crystalline solid that is readily soluble in water. It is stable for up to 7 days as an aqueous solution. All toxins are destroyed by heat and decompose when exposed to air for more than 12 h. 

Canada Minister of National Health and Welfare, Laboratory Centre for Disease Control, Office of Biosafety. Material Safety Data Sheet-Infectious Substances Clostridium botulinum. January 23, 2001. 

Material Safety Data Sheet-Infectious Substances Clostridium botulinum. January 23,2001. 

Specificity against toxins of type A, B or E Clostridium botulinum... 

Botulinum exotoxin impedes release of neurotransmitter vesicles from cholinergic terminals at neuromuscular junctions. Botulinum exotoxin is ingested with food or, in infants, synthesized in situ by anaerobic bacteria that colonize the gut. A characteristic feature of botulinum paralysis is that the maximal force of muscle contraction increases when motor nerve electrical stimulation is repeated at low frequency, a phenomenon attributable to the recruitment of additional cholinergic vesicles with repetitive depolarization of neuromuscular presynaptic terminals. Local administration of Clostridium botulinum exotoxin is now in vogue for its cosmetic effects and is used for relief of spasticity in dystonia and cerebral palsy [21]. 

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