Case study #6 Clostridium botulinum is the causative agent o…

Case study #6 Clostridium botulinum is the causative agent of botulism. This Gram-positive, anaerobic bacillus is commonly found on plants, in soil and water, and in the intestinal tract of some animals. The main virulence factor of C. botulinum is botulism toxin, which is a protein neurotoxin that causes muscle paralysis. Death results from paralysis of respiratory muscles. Genetic analysis has led to the understanding that C. botulinum has acquired its toxin genes from lysogenic bacteriophages. Adults who ingest C. botulinum spores alone generally do not become ill. However, adult botulism will result after ingestion of food containing botulinum toxin. Boiling and common chemical treatments used for water denatures botulism toxin. Infantile botulism, rather, results after children under the age of one ingest foods, such as honey, which contains C. botulinum spores but no botulinum toxin. Once inside the infant gut, these spores germinate and botulism toxin is produced after colonization. Treatment for botulism requires injections of botulinum antitoxin, pre-made antibodies that are administered to the patient as quickly as possible.   Choose all that apply: Treatment for botulism

Case study #3 Dental caries (dental decay) is the result of…

Case study #3 Dental caries (dental decay) is the result of solubilization (dissolving) of tooth enamel by acid. The microbes associated with cavities, usually the Gram-positive Streptococcus mutans and Lactobacillus species living in biofilms as plaque, produce organic acids as the waste product of a specific metabolic pathway. Regular tooth brushing and chewing gum after meals, which increases saliva production, and are the two leading methods that can be preformed daily to prevent tooth decay.   The increased saliva production is a mechanical defense that is triggered by chewing gum. This is part of

Case study #4 Plasmodium falciparum is the most virulent cau…

Case study #4 Plasmodium falciparum is the most virulent causative agent of malaria. This parasite has a trophozoite form that must undergo a life cycle within the gut of the female Anopheles mosquito to be naturally transmitted to the next host. The parasite also has separate trophozoite forms in the liver and blood of humans. If the malaria parasite is introduced into a pregnant woman, it can cross the placental barrier and infect the developing fetus. People at increased risk for malaria infection are children under 5 years old, pregnant women, and people with AIDS (active HIV infection).   Defend your answer to the previous question – why or why not would chloramphenicol, which binds to the 50S ribosomal subunit, be effective at treating a P. falciparum infection?

Case study #1 NDM-1 is an enzyme that hydrolyzes and inactiv…

Case study #1 NDM-1 is an enzyme that hydrolyzes and inactivates nearly all known β-lactam-class antibiotics. This enzyme requires a metallic ion, usually zinc, to catalyze the hydrolysis reaction. The gene encoding NDM-1 is found on a conjugative plasmid and is efficiently transferred to many Gram negative bacteria.   Which of the following statements about the cell envelope component described in the previous question is true?