BRAINCAKEExotoxins
Exotoxins are soluble proteins made by living bacteria and secreted into their surroundings. They are produced mainly by Gram-positive bacteria, such as Staphylococcus, Clostridium and the bacterium that causes diphtheria, but some Gram-negative bacteria, such as Vibrio cholerae, also produce them.
Because they are released into tissue fluid and blood, exotoxins can act far from the bacteria that made them. Each exotoxin has a specific target, and exotoxins are among the most poisonous substances known: a tiny mass can be lethal.
Exotoxins work in different ways, for example:
• damaging cell membranes: some form pores in the plasma membranes of host cells, so the cells leak and burst (lysis);
Sign in free to see the rest of this lesson, the R.E.C.I.P.E. recall steps and the quiz
BrainCake is free. Make an account in seconds and pick up where this page stops.
Key terms in this lesson
- antibody
- A protein made by plasma cells of the immune system that binds specifically to a particular antigen.
More in Bacteria and Disease
- Exponential Growth
- Bacterial Toxins
- Endotoxins
- Salmonella spp.
- Staphylococcus spp.
- Host Tissue Invasion
- Mycobacterium tuberculosis
- Antibiotics
All 30 lessons in Bacteria and Disease · All Edexcel A-level Biology topics