2.5 Venom Components
Venom arsenals are diverse in complexity and size, but venomous species usually all have some combination of small molecules, proteins, and peptides.
- Snakes’ venom arsenals are comprised of proteins, big molecules made up of amino acids. The two types of proteins in snakes’ venom arsenals are metalloproteinases and three-finger toxins.
- Cone snails’ venom arsenals are comprised of neurotoxins that target the central nervous system.
- Sea anemones’ venom arsenals are comprised of potassium channel blockers that inhibit the movement of potassium out of the cell and across the cell membrane.
Omics refers to branches of life sciences, like proteomics, genomics, metabolomics, that are understood through data analysis.
- The rise of omic technologies have improved the process of identifying the components of a venom arsenal.
- Genetic tools are used to identify all of the peptide genes that have the potential to be expressed in a venom arsenal.
- Through proteomics, crude venom is interpreted in a mass spectrometer that identifies all the peptides that are actually in a venom arsenal.
- This, in turn, has allowed scientists to determine the evolution of the venom peptides over time and better understand peptide functions.
- For example, it is known that cone snails produce anywhere from 50 to 200 different peptides that have different molecular targets and different therapeutic potentials.
Venoms target functional strongholds: blood, brain, and membranes.
- Examples include:
- Cone snail toxins act on receptors found on the membranes of cells as well as on neurons in the brain.
- Snake toxins work on the blood and cause hemorrhages.
- A lot of the compounds found in arsenals of snails and snakes are also found in sea anemones and they have similar physiological effects.
Venom toxins can act on multiple cellular targets to yield physiological effects:
- Neurotoxins prevent nerve cells in the brain from sending signals to the rest of the body.
- Haemotoxins cause red blood cells to burst, leading to a hemorrhage.
- Myotoxins keep muscle cells from contracting properly and can lead to death of muscle cells.