Table 6.

Structural and functional derivations of each toxin type


Toxin type

Derivations
3FTx Basal activity of α-neurotoxicity greatly potentiated by the deletion of the C2 and C3 ancestral cysteines. Functional derivations include binding to the postsynaptic muscarinic acetylcholine receptors, presynaptic neurotoxic action upon the L-type calcium channels, cytotoxic interactions, acetylcholinesterase inhibition, and others.
Acetylcholinesterase None currently documented.
ADAM Prothrombin activation a basal derivation. In Viperidae venoms, proteolytic cleavage of C-terminal domains resulted in myriad of other activities including direct-acting fibrinolytic activity. Liberated disintegrin domain inhibits platelets via GP IIb/IIIa integrin receptor.
BNP Cardiovascular effects independent of the GC-A receptor. Antiplatelet activities evolved for domains upstream of the natriuretic peptide domain.
CVF None currently documented.
CNP-BPP None currently documented.
CRISP Blockage of cyclic nucleotide gated calcium channels.
Crotamine Significant neurotoxic activity, modifying voltage-sensitive Na+ channels, resulting in a potent analgesic effect.
Cystatin None currently documented.
Factor V None currently documented.
Factor X None currently documented.
Kallikrein Derivations affect the blood, particularly targeting fibrinogen.
Kunitz Derivations include inhibition of plasmin and thrombin and the blockage of L-type calcium channels. Structural derivatives form part of neurotoxic complexes with PLA2 molecules.
L-amino oxidase Derivations include hemorrhagic effects, not only by affecting platelet aggregation, but also inhibiting blood factor IX.
Lectin Derivations include stimulation of platelet aggregation (binding GPVI, GPIb, GPIa/IIa or VWF), platelet aggregation inhibition (binding GPIb or GPIa/IIa) or anticoagulant actions by binding blood factors IX, X.
MIT None currently documented.
NGF Immunomodulatory effects mediated through histamine release and plasma extravasation.
PLA2 (type IB) Deletion of pancreatic loop facilitated the derivation of a multiplicity of novel, nonenzymatic activities, including antiplatelet and presynaptic neurotoxicity. Some derivatives are parts of neurotoxic complexes.
PLA2 (type IIA) Derivations include neurotoxic and antiplatelet activity. Some derivatives are parts of complexes.
Sarafotoxin None currently documented.
SPRY None currently documented.
VEGF Sustained hypotension.
Wagerlin None currently documented.
Waprin
None currently documented.