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**LT is an oligometric toxin composed of an enzymatically-active A subunit (30KDa; 2 fragments - A1 and A2) and 5 identical B subunits (12KDa) forming the binding portion (B oligomer)
**LT is an oligometric toxin composed of an enzymatically-active A subunit (30KDa; 2 fragments - A1 and A2) and 5 identical B subunits (12KDa) forming the binding portion (B oligomer)
**It attaches to the brush border of the epithelial cells of the small intestine
**It attaches to the brush border of the epithelial cells of the small intestine
**
**LT causes ADP-ribosylation of the stimulatory subunit of guanine nucleotide binding proteins of the adenylate cyclase complex in eukaryotic cell membranes
**This causes irreversible activation of adenylate cyclase in target cells
**This raises the cAMP level and causes hypersecretion of water and chloride ions into the lumen of the small intestine and inhibits reabsorption of sodium
**The gut becomes distended with fluid and a diarrhoea which lasts several days results
**LT is antigenic