Defense Compounds

Proteins

  1. Vicilin: Interferes with larvae development, dins to chitin matrix of fungi and insects

what people are allergic to when they have nut allergies

  1. Lectins- bind to glycoproteins in herbivore guts and interfere with food absorption

  • Ricin- toxic

  1. Protease Inhibitors- block digestion of proteins in herbivore guts

  2. Amylase Inhibitors- block digestion of starch in Herbivore guts

  3. Protease- breakdown proteins in herbivore guts (digesting herbivore from inside out)

  • Corn produces protease when it is wounded

Lipids

  1. Oxylipins- Act as volatile signals to attract predators (of the herbivores that are trying to eat plant) (Ex: wasps and caterpillars)

  • Fungicides, Bactericides, Insecticides

  • Also involved in wound healing, regulate plant growth, induce senescence (intentionally getting rid of a part)

  1. Hexenals, Hexanols, Hexanals, Hexenols

  • Volatile signals that attract predators

  • Fungicids, bactericides, insecticides

  • Ex: hydroproxy-alpha-linolenic acid

    • Infection> conversion to divinyl ether (fungicide)

    • can be converted to jasmonates which regulate expression of several hundered genes

  1. Alkaloids

  • Synthesized from amino acids

  • Contain nitrogen

  • Stored in vacuole

  • Morphine - powerful pain reliever

  • Codeine

  • Quinine - Treats malaria

    • One of the first anti-malaria drugs

    • bitter tasting

    • in the past, mixed with gin

  • Vincristine/vinblastine - Chemotherapy drugs

    • Vinka-alkaloids, discovered 1950s

    • good at killing rapidly dividing cells

  • Atropine - Used to reduce mucus secretions during surgery (saliva), used to maintain normal heartbeat during surgery, used to treat bradycardia (abnormally slow heart rate)

    • Causes eyes to dilate - used as beauty

    • Comes from species Atropine belladonna

  • Cocaine - used as local anesthetic during nose, mouth, throat surgery, very strong stimulant

  • Nicotine - produced by tobacco plants, effective defense compound for plant, stimulant for humans, can form addictions (like a lot of these other stuff)

  1. Glucosinolates

  • Brassiceae family ( broccoli, mustard, etc)

  • Wounding exposes glucosinolates to thioglucosidases (enzymes), which result in isothiocyanates (mustard oils) which are toxic in high concentrations for herbivores but are medicinal for humans

  1. False amino acids

  • Structurally similar to protein building amino acids

  • Herbivores incorporate these false amino acids into proteins during translation resulting in non-functional proteins

  1. Saponins

  • Soap-like properties

  • Herbivore repellant

  • Examples:

    • Digitoxigenin from Digitalis (foxglove); inhibits Na/K pump in animals, used to treat Chronic Heart Failure (very narrow therapeutic range; too little>no effect, too much>death)

    • Diosgenin (yamonin) from Dioscorea (yams); precursor to progesterone and cortisone

      • used in birth control pills