Cholera is caused by a toxin produced by the bacterium Vibrio cholerae. Ultimately, the toxin leads to the activation of ion channels by Protein Kinase A (PKA), indirectly causing water to leave the cell (following ions out of the cell). This loss of electrolytes and water from intestinal cells into the intestinal lumen, produces the watery diarrhea characteristic of a V.cholera infection. Would you expect lower or higher levels of PKA in cells exposed to the cholera toxin? If you were to measure CAMP levels in these cells, what would you expect to find? Why? How might the cholera toxin modify G-proteins to result in these cAMP levels?

Cholera is caused by a toxin produced by the bacterium Vibrio cholerae. Ultimately, the toxin leads to the activation of ion channels by Protein Kinase A (PKA), indirectly causing water to leave the cell (following ions out of the cell). This loss of electrolytes and water from intestinal cells into the intestinal lumen, produces the watery diarrhea characteristic of a V.cholera infection. Would you expect lower or higher levels of PKA in cells exposed to the cholera toxin? If you were to measure CAMP levels in these cells, what would you expect to find? Why? How might the cholera toxin modify G-proteins to result in these cAMP levels?

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter3: The Plasma Membrane And Membrane Potential

Section: Chapter Questions

Problem 1ACR: When William H. was helping victims after a devastating earthquake in a region not prepared to...

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