Question

your patient has cholera. vibro cholerae secretes an A toxin that is transprted and procssss in the gut cell. all of the following are true except

12. Your patient has cholera. Vibrio cholerae secretes an A toxin that is transported and processed in the gut cells. All of the following are true EXCEPT A) Cholera A toxin cleaves ATP and transfers the ribose-5-phosphate to other proteins B) Cholera A toxin ADP-ribosylates the Go, subunit of heterotrimerie proteins, thereby inhibiting their GTPase activity Cholera A toxin increases the concentration of CAMP and activation of protein kinase An overactive Protein kinase A phosphorylates the CFTR (cystic fibrosis transmembrane conductance regulator) chloride channel so that it remains permanently open Chloride, sodium and water move into the bowel lumen causing diarrhea and subsequent dehydration

Answer 1

D ans,

Protein kinase A phosphorylase the CFTR so that it remain permanently open. This option is incorrect

CFTR (cystic fibrosis transporter regulator) is transporter of chloride ion which always remain open if there is mutation at phenylalanine (point mutation).

It's open because of change in structure due to mutation not because of phosphorylation by protein kinase A.

Rest all are function of function of cholera toxinA.

Hope it's clear..thanks