Secondary Metabolites, Toxins, and Natural Products

Vocabulary practice flashcards covering secondary metabolites, categories of plant and animal toxins, opioid history, conotoxins, mimicry, poisonous plants, fungal drugs, and marine natural products.

Secondary metabolites

Molecules not essential for cell structure or growth, often unique to a species or species group, that function in defense, attraction, protection, and competition; over $100{,}000\text{s}$ of types exist, and $60\%+$ of currently available drugs are of natural origin.

Phenolics

A category of secondary metabolites that act as antioxidants with intense flavors and smells (such as vanilla, chocolate, and lignins) and mop up free radicals for protection.

Alkaloids

A category of bitter-tasting secondary metabolites used for defense that contain a cyclic nitrogen ring, including caffeine, nicotine, and atropine.

Papaver somniferum

The poppy plant whose use dates back to the Stone Age; its seed pod contains chemicals harvested via "poppy tears."

Carfentanil

A potent synthetic opioid noted as an elephant tranquilizer.

Terpenoids

A category of secondary metabolites composed of a $5\text{-carbon}$ isoprene ring that produce intense colors and gaseous smells, including steroid hormones and cinnamon.

Polyketides

A category of secondary metabolites produced as chemical weapons, including antibiotics and tetrodotoxin found in the blue-ringed octopus.

Cone snails

A group of $800+$ species of carnivorous, predatory, and venomous marine snails found in tropical and subtropical environments that hunt marine worms and small fish.

Radular tooth (cone snail)

A hollow, barbed, chitinous tooth located at the end of the proboscis and attached to a venom gland, used like a harpoon to hunt prey.

Conotoxins

Venom peptides from cone snails containing $50\text{--}200$ different compounds across $5$ types (alpha, delta, kappa, mu, omega) that act as analgesics $1000\times$ more powerful than morphine for back injuries and phantom pain.

Omega conotoxin

A specific type of conotoxin that targets voltage-gated calcium channels.

Ziconotide (Prialt)

An analgesic drug derived from cone snail conotoxins.

Aposematism

Warning coloration consisting of brilliant colors and patterns associated with toxic substances; an anti-predation strategy that is beneficial to both predator and prey.

Dendrobatidae

The family of poison dart frogs native to Central and South America that obtain their toxins from the arthropods they consume.

Batesian mimicry

A deceptive anti-predation strategy ("a bluff") in which a non-toxic organism resembles a toxic one.

Müllerian mimicry

An "honest" form of mimicry in which multiple resembling species are all toxic to some degree.

Ricin

A highly toxic protein found in the seeds of the castor bean plant that is $6000\times$ more toxic than cyanide.

Amatoxins and psilocybin

Active secondary metabolites derived from fungal sources (mushrooms).

Ara-A and Ara-C

Sponge-derived bioactive compounds that possess antiviral, anticancer, and anti-inflammatory properties.

Marine natural products

An interdisciplinary field combining pharmacology, organic chemistry, biology, ecology, and bioengineering, from which over $12{,}000+$ compounds have been isolated.