Main Animal Toxin Classes

Cardioactive, hemotoxins, myotoxins, neurotoxins, vasoactive

Many of these toxins have other activities other than the activity listed. In addition, many toxins are found in other species as well but often in much lesser amounts.

C A R D I O A C T I V E   T O X I N S
Cardiotoxins/
cytotoxins
Act on membrane lipids/proteins of blood cells or heart cellscobras, scorpions
Digoxin-likeCardiotonic steroids that produce severe arrythmia of heartbeattoads
H E M O T O X I N S
Protease inhibitorsBlockage of serine proteases including plasmin, thrombin and kallikrein resulting in anticoagulant activity or hypotensionSnakes (elapids and true vipers) and certain scorpion species. Leeches contain the most powerful antithrombin toxin known
Factor X activatorPrematurely activates factor X of the blood coagulation resulting in net anticoagulationViper and elapid venoms
Protein C activatorsPremature activation of protein C in the coagulation cascade resulting in net anticoagulationVipers and colubrids
Prothrombin activatorsPremature activation of prothrombin in the coagulation cascade resulting in net anticoagulationElapid venoms
DisintegrinsAnticoagulants that bind to GPIIb/IIIa receptor on plateletsWide spread in viper venoms and also found in leech toxins
ProteasesMyriad of actions including  conversion of fibrinogen to fibrin and kallikrein like actions.Pit-viper venoms, gila monster venoms
PLA2sHemorrhagicPLA2s with a myriad of activities are scattered widely throughout venoms
M Y O T O X I N S
MyotoxinsSmall proteins that facilitate the destruction of muscle cellsPit-vipers
PLA2Destruction of muscle cellsPLA2s with a myriad of activities are scattered widely throughout venoms
T1 and T2,Lethal mytoxins that produce muscular contractionsChironex fleckeri (sea wasp)
N E U R O T O X I N S
alpha-neurotoxinsPostsynaptic neurotoxins that block the acetylcholine receptor (neuromuscular)Elapid venoms only in snakes, also found in spiders and cone snails
alpha-toxin (scorpion)Presynaptic neurotoxins that act upon sodium channels of mammalsScorpions
beta-toxin (scorpion)Presynaptic neurotoxins that act upon sodium channels of mammalsScorpions
Conatokinsinhibitiors of N-methyl-D- aspartate (NMDA) receptors resulting in an inhibition of NMDA receptor-mediated calcium influx in central nervous system neuronsCone snails
FasiculinsAcetylcholinesteraseDendroaspis (mamba) species
kappa-neurotoxinsPostsynaptic neurotoxins that block the acetylcholine receptors (neuronal)Elapid venoms only
Long and short neurotoxinsPostsynaptic neurotoxins that block the acetylcholine receptorsElapid venoms only in snakes
mu-toxinsDirectly abolish muscle action potentials through the inhibition of muscle sodium channelsspider and cone snail
omega-neurotoxinsPrevent voltage-activated entry of calcium into the nerve terminal and release of acetylcholinecone snails and spiders
PLA2sPresynaptic destruction of nerve cellPLA2s are widespread in venoms
P3High molecular weight toxins from Physalia physalis (portugese man o'war) that reversibly blocks glutamate receptors which are integral parts of the nerve conductance systemPortugues man o'war
Tetrodotoxin-likeacute respiratory failure through paralysis of the respiratory musculature with death as a resultBlue-ringed octopi, poison dart frogs, pufferfish
V A S O A C T I V E
SarafotoxinsVasoconstrictorsMole vipers (Atractaspidae) only
Natriuretic peptidesHypotensive peptidesPlatypus, elapid and pit viper venoms
CrTX -I, -II, -IIIInduce platelet aggregation and act as vasoconstrictors in addition to damaging the uptake/storage of noradrenaline, yet leavingthe postsynaptic contractile systems unchanged, while causing contraction of smooth muscles through the Ca2+ independent release of prostaglandinsCarybdea rastoni ("jimble")
Share