1. A 39 year old US postal worker notices an area of redness and swelling on his left lateral forearm. Six days later he notices that the rash, which is painless, now appears black and swollen. He becomes concerned and goes to the emergency department, where he is subsequently diagnosed with cutaneous anthrax. Which of the following mechanisms is most likely associated with the swelling that surrounds the black rash?
A. SNARE protein cleavage
B. Overactivation of adenylate cyclase by disabling the cAMP Gi subunit
C. Overactivation of adenylate cyclase by activating the cAMP Gs subunit
D. Calmodulin-dependent adenylate cyclase
E. Exotoxin A
Answer:
Cutaneous anthrax, the most common form of anthrax, begins with with a region of localized redness and swelling which then progresses to a black, painless eschar. The lesion commonly involves the face, neck, arm, or hand. Systemic symptoms such as fatigue, malaise, or headache can also be seen. The CDC guidelines for diagnosis of cutaneous anthrax include Gram stain and culture, PCR, and punch biopsy for histopathology. First-line treatment for anthrax is either ciprofloxacin or doxycycline for 7-10 days. …show more content…
EF acts as a calmodulin-dependent adenylate cyclase (Answer D), binding calmodulin and preventing it from stimulating signaling required for the immune response. LF lyses macrophages via unknown mechanism. PA is required for the function of both EF and LF, acting as a cell surface receptor to expose a binding site for EF or
A. SNARE protein cleavage
B. Overactivation of adenylate cyclase by disabling the cAMP Gi subunit
C. Overactivation of adenylate cyclase by activating the cAMP Gs subunit
D. Calmodulin-dependent adenylate cyclase
E. Exotoxin A
Answer:
Cutaneous anthrax, the most common form of anthrax, begins with with a region of localized redness and swelling which then progresses to a black, painless eschar. The lesion commonly involves the face, neck, arm, or hand. Systemic symptoms such as fatigue, malaise, or headache can also be seen. The CDC guidelines for diagnosis of cutaneous anthrax include Gram stain and culture, PCR, and punch biopsy for histopathology. First-line treatment for anthrax is either ciprofloxacin or doxycycline for 7-10 days. …show more content…
EF acts as a calmodulin-dependent adenylate cyclase (Answer D), binding calmodulin and preventing it from stimulating signaling required for the immune response. LF lyses macrophages via unknown mechanism. PA is required for the function of both EF and LF, acting as a cell surface receptor to expose a binding site for EF or