IDI

Página 1

Cholera -

AB5 toxin

B sub unit binds to GM1 receptor of epithelial cell

toxin enters by cell endocytosis

a sub unit cleaves from b subunit

a subunit is an ezyme called ADP-ribosyl transferase

a sub unit transfers ADP-ribose moiety from NAD+ to g protein

the ribsoming of g protein leads to 100 fold increase in production of cAMP

na+ is prevent from entering cells, chloride transfer protein is phosphoryised.

ions move into lumen, water moves by osmosis Leads to rice water stool.

Diphtheria -

AB toxin

B toxing binds to herapin like binding site on the epithelial cells

enters cell through an endsome

acidification of the endosome unfolds protein

t domain of b subunit creates a pore in the endosome in which the a subunit can pass through

a subunit is an enzyme adp-ribosyl transferase

adp-ribosyl transfers adp-ribose moiety from NAD+ to EF2 which prevents protein synthesis

shiga toxin-