Exotoxin
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An exotoxin is a soluble chemical excreted by a microorganism, including bacteria, fungi, algae, and protozoa. This is a type of toxin that is produced by bacteria and released into the bloodstream. These toxins can cause damage in the body by destroying cells or disrupting normal cellular metabolism.
There are three main types of exotoxins:
a)toxins that act upon the extracellular matrix or connective tissue - this allows the further spread of bacteria and therefore the infection deeper into tissue regions.
b)A-B type toxins - the 'B'-subunit attaches to target regions on cell membranes, the 'A'-subunit tends to have an enzymatic function and enters through the membrane affecting the internal bio-mechanisms.
c)Membrane damaging toxins - these toxins are designed primarily to puncture and disrupt the cellular membrane killing cells, a significant resulting example is that of Gangrene.