Abeer Tadrus and Hadjer Sahraoui BIO-325-01
Dr. McLaughlin 3/20/2014
Clostridium perfringens
Clostridium perfringens is a gram-positive spore-forming bacillus involved in foodborne illness and wound infection. It is an obligate anaerobe and the only member of the genus Clostridium that is non-motile. This microorganism is normally present in soil and decaying vegetation and is an inhabitant of animal and human intestines. According to the Centers for Disease Control and Prevention, C. perfringens is one of the most common sources of foodborne illness in the United States, being the cause of an estimated 1 million cases each year. However, it is also prevalent worldwide. This bacterium has the shortest reported generation time of any organism at 6.3 minutes in thioglycollate medium, making it particularly virulent after initial inoculation.
Some strains of this microorganism produce C. perfringens enterotoxin (CPE), a group of toxins that cause a variety of adverse effects in the host. Strains of C. perfringens are classified as 5 biotypes, A – E, depending on the production of four major enterotoxins (α, β, ε and ι). In addition, strains of C. perfringens may also produce a number of other toxins including neuraminidase, hyaluronidase, and collagenase. For example, α-toxin, produced by C. perfringens type A, is primarily responsible for the production of gas gangrene. However, only roughly 5% of C. perfringens carry the CPE gene that codes for the production of these toxins. CPE is inactivated at 74oC.
Infection with C. perfringens as a food-borne illness is acquired from consumption of food or water that has come in contact with the bacterium. Some possibilities include unwashed fruits and vegetables, undercooked me...
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...50% of healthy humans. According to the results of this study, 52% of the healthy controls (n = 31) were carriers of C. perfringens type A. This study showed that 23% of C. perfringens type A is present in individuals with MS. In other words, Clostridium perfringens type A, which is commensal to humans, was present in roughly half of healthy the healthy controls as opposed to 23% in patients with MS. Also, 10% of MS patients and 1% of controls possessed ETX specific antibodies.
For CSF, 6 of 62 MS patients, and 1 of 40 controls, were positive for ETX immunoreactivity. For the analysis of sera, 6 of 56 MS patients, and 0 of 60 controls were seroreactive to ETX.
According to this experiment, it is clear that C. perfringens has specificity toward CNS epithelial cells and white matter. It is further studied that EXT binds to retinal vessels and myelin in the cranium.
Clostridium difficile, otherwise known as C. diff, is a species of spore-forming, anaerobic, gram-positive bacteria that is known to cause watery diarrhea. 1 The genus name, Clostridium refers to the spindle shape of the organism while Difficile means difficult in Latin due to the fact that this organism thrives in unfavorable conditions and is very difficult to isolate.4 The incidence of getting CDI has increased over the years due to new strains of increased toxin production of the bacteria and increased resistance to antibiotics.2 It is a gastrointestinal infection, and the most common cause of infectious diarrhea.1 C. difficile was first identified in the feces of healthy newborns back in the 1930’s and by 1935, it was considered normal flora. 2 During 1974, researchers conducted that about 21% of patients that were treated with an antibiotic called clindamyacin reported diarrhea and about 10% of them reported to have conducted pseudomembranous colitis as a side effect of this treatment. 2 It was in 1978 where C. diff had been known to cause anti-biotic associated diarrhea and pseudomembranous colitis. 2 It is known to form spores that resist many disinfectants; it also survives for several months on different surfaces.1 It is a common form of a nosocomial infection and the prevalence of becoming infected with C. diff is about 0-15% in a health care setting. 3 The spores survive well in environments such as soil, water and animals and is distributed worldwide. 4 CDI produces two toxins (Toxin A and B), which are cytotoxic and cause tissue necrosis.4
Bordetella pertussis is a highly communicable agent and is transmitted person-to-person via airborne droplets or direct contact with discharges from the respiratory mucous membranes of an infected person. This small, gram-negative coccobacillus is non-motile, aerobic and fastidious. B. pertussis colonizes the respiratory tract including the mouth, nose, throat and beginning of the lungs of young children worldwide. The bacteria bind to ciliated cells in the respiratory mucosa by producing adhesions. Filamentous hemagglutinin on the cell surface and pertussis toxin (Ptx) both help the bacteria in binding. Filamentous hemagglutinin binds to the galactose residues on the glycolipid of the ciliated cells. Ptx, in its cell-bound form, binds to the glycolipid lactosylceramide, which is also found on the ciliated cells. Ptx binds to the surface of phagocytes as well, causing phagocytosis of the bacteria. This mechanism may lead to enhanced survival as an intracellular parasite. Adding to its many purposes, Ptx deregulates the host cell adenylate cyclase activity. The A subunit of this AB toxin, affects the G protein responsible for inhibiting adenylate cyclase. This leads to an increase in cyclic adenosine monophosphate (cAMP) creating detrimental metabolic changes in the host cells.
Multiple sclerosis (MS) is a disease affecting the myelination of the central nervous system, leading to numerous issues regarding muscle strength, coordination, balance, sensation, vision, and even some cognitive defects. Unfortunately, the etiology of MS is not known, however, it is generally thought of and accepted as being an autoimmune disorder inside of the central nervous system (Rietberg, et al. 2004). According to a study (Noonan, et al. 2010) on the prevalence of MS, the disease affects more than 1 million people across the world, and approximately 85% of those that are affected will suffer from unpredictably occurring sessions of exacerbations and remissions. The report (Noonan, et al. 2010) found that the prevalence of MS was much higher in women than in men, and that it was also higher in non-Hispanic whites than in other racial or ethnic groups throughout the 3 regions of the United States that were studied.
The disease, botulism, which is caused by Clostridium botulinium, is an emerging infectious disease. Clostridium botulinium is a bacterium that produces a neurotoxin that causes botulism. The bacterium is spore-forming, and anaerobic, meaning it does not need oxygen to grow. There are three main types of illnesses that Clostridium botulinium typically cause: Food-borne botulism, infant botulism, and wound botulism. Unbeknownst to common knowledge, infant botulism is the most common form of the disease, consisting of seventy-five percent of the reported cases of the disease (Chan-Tack, & Bartlett, 2010).
Botulinum toxin has a complex chemical composition and is found in various surprising locations. The toxin is derived from Clostridium botulinum, and according to P.K. and Anjana Nigam, the authors of the Indian Journal of Dermatology, it is “an anaerobic, gram-positive, spore-forming rod commonly found on plants, in soil, water and the intestinal tracts of animals.” H. Bradford Hawley M.D., the editor of Magill’s Medical Guide, states that these bacteria are vastly immune to high temperatures and can persevere through numerous methods used to eradicate it and to get rid of toxins for secure consumption of food and water. Since the bacteria can be found in such a diverse variety of commodities, which all can be ingested by humans, it is critical to find a way to disinfect our soil, meat, and produce against C. botulinum.
Bacteria play a large role in our health, the environment, and most aspects of life. They can be used in beneficial ways, such as decomposing wastes, enhancing fertilizer for crops, and breaking down of substances that our bodies cannot. However, many bacteria can also be very harmful by causing disease. Understanding how to identify bacteria has numerous applications and is incredibly important for anyone planning to enter the medical field or begin a career in research. Having the background knowledge of identifying an unknown bacteria may one day aid healthcare professionals diagnose their patient with a particular bacterial infection or help researchers determine various clinical, agricultural, and numerous other uses for bacteria.
E. coli are bacteria that can cause an infection in various parts of your body, including your intestines. E. coli bacteria normally live in the intestines of people and animals. Most types of E. coli do not cause infections, but some produce a poison (toxin) that can cause diarrhea. Depending on the toxin, this can cause mild or severe diarrhea.
Many say that history repeats itself, and throughout history, the spread of food-borne diseases has been constantly threatening humans. Salmonella, a disease which attacks numerous people a year, has returned, infected, and put people under panic of what they are eating. According to Foodborne Diseases, it is stated that “Salmonella comprises a large and diverse group of Gram-negative rods. Salmonellae are ubiquitous and have been recovered from some insects and nearly all vertebrate species, especially humans, livestock, and companion animals” (Gray and Fedorka-Cray 55). Because of the flexibility and the ability to reproduce rapidly, this infamous disease still remains as one of the most common threats in our society as well as an unconquerable problem that humans face these days.
So what is happening chemically to the people with MS? The disease is an Autoimmune which this will destroy the cells which are in your body. The immune system is going to attack the tissue which it is going to affect the Myelin. When the Myelin is damaged which is when the T cells over react , and cause them to damaged. That is what happens Chemically with MS people.
In crowded conditions, the rate of infection is even more rapid. The diseases brought over to America were mainly spread by the respiratory method. The pathogenesis of infection is through the ingestion of contaminated food and water. Throughout Europe during the 15th century, food and water were contaminated with fecal matter and by unsanitary habits ( i.e. the lack of bathing). The traumatic route of infection is through insect and animal bites.
According to National Multiple Sclerosis Society, Multiple Sclerosis (MS) is an unpredictable, often disabling disease of the central nervous system (CNS) that disrupts the flow of information within the brain, and between the brain and body. The central nervous system (CNS) comprises of the brain and the spinal cord. CNS is coated and protected by myelin sheath that is made of fatty tissues (Slomski, 2005). The inflammation and damage of the myelin sheath causing it to form a scar (sclerosis). This results in a number of physical and mental symptoms, including weakness, loss of coordination, and loss of speech and vision. The way the disease affect people is always different; some people experience only a single attack and recover quickly, while others condition degenerate over time (Wexler, 2013). Hence, the diagnosis of MS is mostly done by eliminating the symptoms of other diseases. Multiple sclerosis (MS) affects both men and women, but generally, it is more common in women more than men. The disease is most usually diagnosed between ages 20 and 40, however, it can occur at any age. Someone with a family history of the disease is more likely to suffer from it. Although MS is not
Pertussis, also known as whooping cough, is a respiratory tract infection characterized by a violent cough. The violent cough incudes a series of severe uncontrollable coughing, hacking, or whooping. (1) Pertussis is a very contagious disease caused by bacteria named Bordetella pertussis, which is transmitted through fluids from sneezing or coughing around a person’s breathing space. The bacteria release toxins, damage cilia, and cause airways to swell.
Among hospitalized patients around the world, Clostridium difficile is the primary source of infectious diarrhea. Previously, continuously unbalanced intestinal microbiota, usually due to antimicrobials, was deemed a precondition for developing the infection. However, recently, there have been alterations in the biology from virtually infecting the elderly population exclusively, wherein the microbiota in their guts have been interrupted by antimicrobials, to currently infecting individuals within of all age groups displaying no recent antimicrobial use. Furthermore, recent reports have confirmed critical occurrences among groups previously assumed to be of minimal risk—pregnant women, children, and individuals with no previous exposure to antimicrobials, for instance. Unfortunately, this Gram-positive, toxin-producing anaerobic bacterium is estimated to cost US critical care facilities $800 million per year at present, suggesting the need for effective measures to eliminate this nosocomial infection (Yakob, Riley, Paterson, & Clements, 2013).
The most commonly recognized food borne infections are those caused by the bacteria Campylobacter, Salmonella, and E. coli 0157:H7, and by a group of viruses called Calicivirus, also know as the Norwalk viruses. “Thousands of types of bacteria are naturally present in our environment, but not all bacteria cause disease in humans.” (Schmutz 1)
T. pallidum is highly sensitive to oxygen and has a decreased ability to survive when not in human body temperature environments 1. The mode of transmission is through sexual contact or vertical transmission from the mother to the fetus. T. pallidum lacks the lipopolysaccharide which is the endotoxin normally present in gram negative bacteria1. The bacterium does produce many lipoproteins which are thought to prompt the inflammatory mediators through the recognition of toll-like receptors1. T. pallidum has a virulence factor of being highly motile due to its ability to propel itself forward by rotating on a longitudinal axis1. The spirochetes easily penetrate the skin or mucosal membranes and spread throughout the lymph nodes and then the blood circulation, affecting many parts in the body1.