Passage 3 (Questions 11 - 15)A woman began canning her own jams as a hobby. She shared several cans of her jam with her mother for lunch. The next day, her mother was found suffering from blurry vision, difficulty swallowing and troubled breathing. Given the quick progression of symptoms, associated with the new food, the ER physician suspected botulism poisoning. Due to the danger and toxicity of botulism, tests were performed immediately to determine the best course of treatment.The botulinum toxin is a neurotoxin produced by the bacterium Clostridium botulinum. Botulism is a life-threatening illness in humans, although forms of the toxin are used for various cosmetic and medical procedures. The eight distinct toxin types are designated A to H. The botulinum toxin protein is a two-chain polypeptide with a 100-kDa heavy chain joined by a disulfide bond to a 50-kDa light chain. This light chain is a protease that attacks one of the fusion proteins (SNARE protein) present in neuromuscular junctions, preventing vesicles from anchoring with the cell membrane to release acetylcholine.Figure 1 Mechanism of neuromuscular blockade by botulinum toxinThe tests employed to detect botulism include brain scans and nerve conduction tests. Toxicity testing of serum specimens, wound tissue cultures, and stool specimen cultures are the best methods for identifying botulism, though they are time-consuming. If the symptoms are diagnosed early, treatment can reduce the case fatality rate to less than 10%, while untreated botulism is fatal in nearly half of cases. A more rapid way to detect the toxin in humans utilizes mass spectrometry. Question 12The easiest method to separate the two subunits of the botulinum protein for subsequent analytical purposes would be: A.gas chromatography.B.mass spectrometry.C.thin-layer chromatography.D.size-exclusion chromatography.

assage 3 (Questions 11 - 15)A woman began canning her own jams as a hobby. She shared several cans of her jam with her mother for lunch. The next day, her mother was found suffering from blurry vision, difficulty swallowing and troubled breathing. Given the quick progression of symptoms, associated with the new food, the ER physician suspected botulism poisoning. Due to the danger and toxicity of botulism, tests were performed immediately to determine the best course of treatment.The botulinum toxin is a neurotoxin produced by the bacterium Clostridium botulinum. Botulism is a life-threatening illness in humans, although forms of the toxin are used for various cosmetic and medical procedures. The eight distinct toxin types are designated A to H. The botulinum toxin protein is a two-chain polypeptide with a 100-kDa heavy chain joined by a disulfide bond to a 50-kDa light chain. This light chain is a protease that attacks one of the fusion proteins (SNARE protein) present in neuromuscular junctions, preventing vesicles from anchoring with the cell membrane to release acetylcholine.Figure 1 Mechanism of neuromuscular blockade by botulinum toxinThe tests employed to detect botulism include brain scans and nerve conduction tests. Toxicity testing of serum specimens, wound tissue cultures, and stool specimen cultures are the best methods for identifying botulism, though they are time-consuming. If the symptoms are diagnosed early, treatment can reduce the case fatality rate to less than 10%, while untreated botulism is fatal in nearly half of cases. A more rapid way to detect the toxin in humans utilizes mass spectrometry. Question 13Which molecule could be used to specifically detect toxin D in the cultures described in the passage? A.An antibodyB.A phospholipidC.A radiolabeled thymineD.An antigen

Botulism is caused by ingestion of a proteinaceous exotoxin; therefore, it can easily be prevented byGroup of answer choicesnot eating canned food.boiling food prior to consumption.administering antibiotics to patients.filtering food.preventing fecal contamination of food. Flag question: Question 2

Botulism is caused by ingesting __________.ANSWERexotoxinsGram-negative organismsendotoxinsacid-fast organisms

A 47-year-old woman was admitted to the hospital afterexperiencing nausea and vomiting for about 2 days followed bysevere muscle weakness and neurologic symptoms, includingptosis and dysphagia. She indicated she had eaten at a restaurantthe evening before the symptoms began. Laboratory tests werepositive for Clostridium botulinum. The basis for the muscleweakness in this case was most likely because the toxinA. blocked the reuptake of neurotransmitter into presynapticterminals.B. bound irreversibly to the receptor on the postsynapticmembrane at the neuromuscular junction.C. reached the cell body of the motor neuron by diffusion intothe spinal cord.D. exerted its adverse effects by a direct action on the skeletalmuscle.E. prevented the release of acetylcholine from motor neurons.

Infant botulism occurs when the botulism bacterium grows in the digestive tract of an infant. The spores of the bacterium are most likely introduced when the infant is fed honey or exposed to the spores in soil. The infection is very serious but can be treated. In infants, botulism immune globulin is administered. This substance binds to the toxin produced by the bacterium and inactivates it. Which type of acquired immunity is represented by this treatment of infant botulism?Multiple ChoicePassive natural immunityActive artificial immunityActive natural immunityPassive artificial immunity