Vibrio Cholerae

Question 1

Characteristics - Vibrio Cholerae

Answer 1

Gram negative, curved rod. Facultative anaerobe

Question 2

Diseases caused - V. Cholerae

Answer 2

Cholera, cholera-like diarrhoea, gastroenteritis, soft tissue infections.

Question 3

Adhesion Virulence factors - V. Cholerae

Answer 3

Single polar flagella, toxin-coregulated pili (TCP) (bacterial aggregation)

Question 4

Invasion factors - V. Cholerae

Answer 4

acf gene cluster is responsible for chemotaxis, Zot (explained in toxins)

Question 5

Toxins - V. Cholerae

Answer 5

Cholera toxin is an AB5 toxin which is ADP ribosylating, it will perminantly activate the Gs protein which increases cellular cAMP, leading to ion transporters effluxing ions and H2O. Zot affects structure of intracellular tight junctions which increases permeability of intestinal mucosa. ACE induces fluid accumulation

Question 6

Pathogenesis of V. Cholerae

Answer 6

Cholera enters body though ingestion. It will then mobilise to find the intestinal mucosa through flagella and Acf. From here, flagella and TCP will bind to the host cell and CTX and Tox regulation will be activated which will activate the rest of the virulence factors. Zot affects intracellular tight junctions, increasing permeability of intestinal mucosa and the cell will produce cholera toxins and ACE to remove fluid from the cell.

Question 7

How is V. Cholerae detected?

Answer 7

Through extremely watery stools – rice water consistency

Question 8

How is V. Cholerae treated?

Answer 8

If untreated can lead to death through fluid loss and hypovolemic shock. If treated with fluid replacement, full recovery is expected.