Plant Adaptation And Survival 2024-2025 PDF
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2025
Mr. Jeremiah Estrada
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This document is about plant adaptation and survival, covering various topics relating to secondary products such as terpenoids and phenolics. It discusses their function and biosynthesis, and provides examples of different types and sources of these substances. This document is instructional in nature and appears to be lecture notes.
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PLANT ADAPTATION AND SURVIVAL BIO 191 FIRST SEMESTER | ACADEMIC YEAR 2024-2025 | MR. JEREMIAH ESTRADA...
PLANT ADAPTATION AND SURVIVAL BIO 191 FIRST SEMESTER | ACADEMIC YEAR 2024-2025 | MR. JEREMIAH ESTRADA Cyanogenic glycosides INTRODUCTION TO PLANT SECONDARY PRODUCTS Serve as attractants for pollinators and fruit0dispersing animals ○ Terpenes Carotenoids Primary Metabolites ○ Phenolics ○ Present in all cells Anthocyanin ○ Play DIRECT roles in metabolism Flavones ○ Molecules which are products of major pathway ○ Nitrogen-containing compounds Carbohydrates (sucrose, starch, cellulose) Betacyanins Proteins (amino acids) Lipids (fatty acids) Nucleic acids Chlorophyll Why are plants not poisoned by their own toxic secondary metabolites? ○ Found in ALL plants ○ Commercially important as food sources Stored as inactive precursors separate from their activating Secondary metabolites enzymes ○ Metabolic diversion of a product from a major pathway Have modifications rendering them insensitive to toxic effects ○ Restricted distribution Stored away from sensitive metabolic processes ○ FUNCTION Plant defense TERPENES Pollination Competition ○ Commercially important in medicines and industries Aromatic compounds found in plants Unsaturated hydrocarbons ○ Meaning they have one or more carbon-carbon double Principal Groups of Secondary Metabolites or triple bond Produced predominantly by plants, particularly conifers Terpenoids Commonly associated with Cannabis (Cannabaceae – Hemp family ○ From acetyl-coA via mevalonic acid pathway which contains high concentration of terpenes) ○ Examples ○ Cannabis sativa, marijuana Essential oils Biggest class of secondary metabolites Lycopene Consist of five carbon isoprene units which are assembled to each Limonene other (many isoprene units) by thousands of ways Saponin Taxol Carotenoid Sterol Rubber Phenolics ○ From erythrose-4-phosphate and phosphoenol pyruvate (PEP) via shikimic acid pathway ○ Examples Cannabis Terpenes Simple phenolics ○ Bisabolol Vanillin Anti-inflammatory, anti-irritant, anti-microbial Salicylic acid ○ Borneol Flavonoids Antinociceptive, anti-inflammatory Anthocyanin ○ Camphene Flavone Anti-oxidant, skin lesion Isoflavonoide ○ Caryophyllene Lignins Anti-bacterial, antifungal, anti-inflammatory Tannins ○ Delta 3 Carene Nitrogen-containing Compounds Anti inflammatory, bone stimulant ○ From amino acids (usually from lysine, phenylyalanine, ○ Eucalyptol tyrosine, and tryptophan) Antibacterial, antifungal These are essential amino acids ○ Geraniol ○ Examples Anticancer, antioxidant, neuroprotectant Alkaloids ○ Humulene Cyanogenic glycosides Anti-bacterial, anti-inflammatory, anti-tumor Non-protein amino acids ○ Limonene Canavanine Antianxiety, anticancer, digestion, gallstones ○ Linalool Function of Secondary Metabolites Antianxiety, anti-epileptic, antipsychotic, pain killing ○ Myrcene Defend plants against herbivore and pathogen attack Relaxing and sedating ○ Terpenes ○ Pinene Essential oils anti-depressant , anti-inflammtory, Saponins anti-microbial Rubber ○ Phytol ○ Phenolics Anti-insomnia, immunosuppressant Lignins ○ Terpinolene Tannins Antibacterial, antifungal, antiinsomnia, Isoflavonoids antiseptic ○ Nitrogen-containing compounds Alkaloids BIO 191: PLANT ADAPTATION AND SURVIVAL 1 PLANT ADAPTATION AND SURVIVAL BIO 191 FIRST SEMESTER | ACADEMIC YEAR 2024-2025 | MR. JEREMIAH ESTRADA ○ Trans-nerolidol Terpene Biosynthesis Anti-cancer, antimicrobial, anti-oxidant, anti-parasitic The process begins with small molecules called isoprene units. ○ Valencene These isoprene units combine to form a bigger chain called IPP Antiallergic, anti-inflammatory, (isopentenyl pyrophosphate). Another similar molecule, DMAPP anti-melanogenesis (dimethylallyl pyrophosphate) ○ IPP and DMAPP are isomeres meaning they have the same chemical formula but have different arrangements Five Most Common Terpenes in atoms ○ Isopentenyl pyrophosphate isomerase catalyzes the Myrcene isomerazation of IPP to DMAPP and vice versa ○ Herbal ○ Found in hops, mango and lemongrass Pinene ○ Pine ○ Found in needles, rosemary, basil and dill IPP + DMAPP → Hemiterpenes Caryophyllene IPP + DMAPP = GPP → Monoterpenes ○ Perppery GPP → FPP → Sesquiterpenes and Triterpenes ○ Found in black pepper, cloves and cinnamon FPP → GGPP → Diterpenes and Tetraterpenes (carotenoids) Limonene Terpene Synthase catalyzes the formation of these structures ○ Citrus Hemiterpenes ○ Found in fruits rinds, rosemary, juniper and peppermint Terpinolene ○ Fruity ○ Found in nutmeg, tea tree, cumin and lilacs Terpene Biosynthesis Smalles and simplest (C5H8) Plants use carbon dioxide (CO2) and water (H2O) to create energy Isoprene – the only and most prominent hemiterpene through photosynthesis. ○ Released as gas This energy enters primary carbon metabolism, which provides ○ May help protect against heat stress building blocks for making important compounds in the plant. ○ Conifer trees, poplars, oaks, and willows Results in: Examples: ○ Eyrthrose-4-phosphate ○ Archangelica officinalis (Angelic acid) ○ Phosphoenolpyruvate (Glycolysis) ○ Croton tiglium (Tiglic acid) ○ Pyruvate (Glycolysis) ○ Levisticum officinale (Angelic acid) ○ 3-phosphoglycerate ○ Valeriana officinalis L. (Isovaleric acid) There are two terpene-making pathways ○ Senecio sp. (Senecionic acid) ○ Mevalonic Acid Pathway ○ Ligularia sp. (Senecionic acid) Occurs in cytosol and mitochondria ○ Tuber melanosporum (Isoamyl alcohol) ○ MEP Pathway Functions of Hemiterpenes Chloroplast ○ Provide coloration as attractant Difference between Terpenes and Terpenoids ○ Provide color for photoprotection and photosynthesis Terpenes are simple hydrocarbons while Terpenoids/Isoprenoids ○ VOCs (gases) as attractant are modified family of terpenes with various functional groups and ○ Deter herbivores and pathogens an OXIDIZED methyl group relocated or removed Monoterpenes Consists of 2 isoprene units (C10H16) CLASSIFICATION OF TERPENOIDS Compounds found in essential oils Depends on the number of carbon and isoprene units ○ Contributes to flavor and aroma Classes of Terpenoids Camphor, citral, eucalytol, myrcene, and pinenes ○ Monoterpenes Volatile oils (VOs) 10 carbons Example: 2 isoprene unites ○ Cinnamomum camphora Example: Myrcene Accumulate in trichomes on the leaves and stems ○ Sesquiterpenes Gives the plant its characteristic odors once damaged 15 carbons Functions of Monoterpenes 3 isoprene units ○ Insect repellents Example: Cadinene ○ Deter predators ○ Diterpenes ○ Distress signals along with VOCs 20 carbons PYRETHRINS 4 isoprene units ○ Most potent natural insecticide Example: Giberellic acid ○ Produced abundantly in the flowers of Chrysanthemum ○ Triterpenes species 30 carbons ○ Act against the nervous system of insects → paralyzing 6 isoprene and killing them if they attempt to eat the leaves Example: Progesterone ○ Little effect on mammals ○ Tetraterpenes ○ Short-lived in air and biodegredable 40 carbons ○ Examples 8 isoprene Chrysanthemic acid Carotenoids Pyrethric acid Both have been used as the bases for pyrethroids (synthetic insecticides) BIO 191: PLANT ADAPTATION AND SURVIVAL 2 PLANT ADAPTATION AND SURVIVAL BIO 191 FIRST SEMESTER | ACADEMIC YEAR 2024-2025 | MR. JEREMIAH ESTRADA Sesquiterpenes ○ Phytoecdysones A plant hormone/steroid Consists of 3 isoprene units (C15H24) Mimics the activity of molting hormones Accumulate in trichomes on the leaves and stems Disrupts insect life cycle (causes death) Examples Produces hormones calles ecdysteroids ○ Gossypium hirsutum (Gossypol) Example ○ Piper nigrum (α–bisabolene in black pepper) Ajuga remota (Bugleweed) ○ Cananga odorata (β-caryophyllene in ylang-ylang) Azadirachtin ○ Lactucin ○ Bitter-tasting feeding deterrent and insecticide Bitter-tasting in lettuce and chicory ○ Functions ○ β -Caryophyllene Inhibit larval, pupal, and adult moults Major scent of Scots pine Inhibit reproduction of both plant feeding and ○ α-Farnesene aquatic larvae mosquitoes Volatile signal in Norway spruce (Picea abies) Acts as antifeedent and growth disruptor ○ Germacrene B (inhibits molting hormone production) Volatile signal in spruce (Picea abies) and Azadirachta indica (Neem Tree) (Juniperus communis) ○ Capsidiol Saponins A phytoalexin ○ Water- and lipid-soluble triterpenes with soap-like Gossypol (in seeds of cotton) properties ○ A phytoalexin ○ bitter -tasting feeding deterrents Low molecular weight antimicrobial and ○ Bind sterols interfering with membrane function antibiotic compounds ○ Cause hemolysis or breakdown of red blood cells They are produced in response to biotic and ○ Distributed in all cells of legume plants abiotic stresses ○ Solanine ○ Similar to capsidiol in capsicum peppers Glycoalkaloid poison Diterpenes Produce by plants of the Solanaceae family Contains 4 isoprene units (C20H32) such as Most diterpenes are NON-VOLATILE Solanum nigrum Examples Solanum melogena ○ Taxus brevifolia (the Pacific yew) Solanum tuberosum ○ Rhododendron sp. ○ Examples ○ Taxol Saponaria officinalis (Soapwort) Antimitotic agent used to treat cancer Chlorogalum pomeridianum (Soaproot) Blocks cancer cell growth by stopping cell Quillaja saponaria (Soapbark) division Sapindus saponaria (Soapberry) Plant immunity compound Sapindus mukorossi (Soapnut) Deployed against wood-degrading fungi Cardenolides ○ Forskolin ○ Type of steroid Insecticidal and anti-feedent properties ○ Cardiac glycosides in the saponin family active against Treatment for glaucoma mammal herbivores ○ Abietadiene ○ Bitter-tasting and very toxic Phytoalexin found in resin of grand fir (Abies Can cause fatalities by absorption through the grandis) skin ○ Grayanotoxin ○ Functions Poison present in rhododendron Inhibit Na/K-ATPases ○ Gibberelin A1 Slows the heartbeat Plant growth regulator Ouabain ○ Plant derived toxic Triterpenes compound Contains 5 isoprene units (C30H40) ○ Traditionally used as an Derived from the squalene biosynthetic pathway arrow poison by Africans Examples both in hunting and ○ Sitosterol warfare Plant sterol ○ Acokanthera schimperi ○ Ponasterone A Cardiac glycoside Insect hormone analog ○ Some insects such as Danaus plexippus (Monarch ○ α-Ecdysone butterfly) can get cardenolides from plants and store Insect hormone analog these to deter predators Monarch caterpillars and grasshopper ○ Digitoxigenin (Poekilocerus bufonius) feed on milkweed The aglycone moiety of digitoxin plants which contain cardenolides A cardiac glycoside of Foxglove Examples of plants the contain cardenolides Digitalis purpurea Asclepias spp. ○ Diosgenin Asclepias curassavica A sapogenin found in Mexican yam that was Polyterpenes used to produce the contraceptive pill ○ β-Carotene Natural or synthetic polymer Pigment involved in photosynthesis and From latex of trees photoreception Produced from laticifers ○ Lycopene Seals injuries Red carotenoid pigment with antioxidant Deter herbivores and pathogens properties Examples ○ Lutein ○ Natural rubber (cis-1,4-polyisoprenoid) Xanthophyll pigment Latex of rubber trees Hevea brasilensis BIO 191: PLANT ADAPTATION AND SURVIVAL 3 PLANT ADAPTATION AND SURVIVAL BIO 191 FIRST SEMESTER | ACADEMIC YEAR 2024-2025 | MR. JEREMIAH ESTRADA Euphorbiaceae ○ Furacoumarins Cis-conformation gives the elastic nature of Psoralen latex Bergapten ○ Gutta percha (trans-1,4-polyisoprenoid) Angelicin Latex from Palaquium gutta trees ○ Pyranocoumarins Sapotaceae Xanthyletin Trans-conformation makes it quite rigid Seselin Example. Coating of golf balls Visamadin ○ Pyrone-substituted coumarins PHENOLICS Dicoumarol Urolithin A Psoralen PHENOLIC ACID ○ A furanocoumarin present in Umbelliferae and Rutaceae ○ Examples Psoralea corylifolia (Babchi) Classification of phenolics Apium graveolens (Celery) ○ Polyphenols Petroselinum crispnum (Parsley) Tannins ○ Sensitive to light or activated by ligbt Falvonoids ○ Used together with UV light to treat psoriasis, vitiligo, ○ Simple Phenols and T-cell lymphoma Phenolic acids ○ Psoralen + UV-A radiation = DNA interstand cross-links Coumarins causing cell death in the herbivores when plant is Structure of phenolics damaged ○ Consists of one or more hydroxyl groups bonded Phototoxic compound DIRECTLY to an aromatic hydrocarbon group Results in severe rash in mammals or death of OH + aromatic hydrocarbon = phenol insects ○ Simplest phenol → C6H5OH ○ NOTE: Psoralen can still exhibit toxic effects and provide Phenolics biosynthesis some level of protection to the plant even without UV 1. Building blocks = basic sugar molecules light, though its efficacy may be reduced. 2. Ribose-5-phosphate from Pentose Phosphate Pathway + Pyruvate from Glycoslysis = Shikimic acid through the Uroshiol Shikimate Pathway (E.g. Phenyalanine; Tyrosine; Tryptophan) 2-hydroxyphenol with alkyl groups substituted onto the aromatic 3. Phenyalanine from Shikimate Pathway is converted to ring phenolic compounds via Phenyl Propanoid Pathway Belongs to a class of compounds known as phenolic lipids a. Coumarin May be stored in specialized structures called resin ducts b. Lignin Also inhibit the growth of competing plants in the vicinity c. Flavone (Allelopathy) d. Flavonol Biosynthesis of Uroshiol e. Anthocyanin ○ It is derived from the shikimic acid pathway f. Condensed Tannins ○ It involves the conversion of cinnamic acid (a phenolic g. Stilbene compound What is allelopathy? ○ Phenyalanine → Cinnamic acid → Uroshiol ○ Chemicals released from plants (roots; leaves) are often Examples simple phenolics such as cinnamic and benzoic acid that ○ Anacardiaceae family influence the growth, survival, development, and Toxicodendron radicans (poison ivy) reproduction of other organisms. Toxicodendron diversilobum (poison oak) ○ Benefits of allelopathy Toxicodendron vernix (poison sumac) Reduced competition Function Improve survival ○ Causes allergic skin rash on contact (Contact dermatitis) ○ Examples of plants the exhibit allelopathy Contact: Uroshiol gets onto the skin. Pteridium acquilinum (Bracken ferns) Langerhans Cells: These immune cells in the Juglans nigra (Black Walnut Tree) skin recognize uroshiol. ○ Water-soluble phenolic acids Loading: The Langerhans cells attach uroshiol Cinnamic acid to special proteins called CD1a molecules. Benzoic acid T Cell Activation: This combination of uroshiol Syringic acid and CD1a activates T cells, which are part of Caffeic acid the immune system, leading to an immune Ferulic acid response. Only insects such as sawfly larvae can attack the plant Coumarins ○ Have specialized digestive enzymes that can break down or neutralize the toxic effects of uroshiol Simplest plant phenolic toxins Pleasant odor-bitter taste Gives the smell of a freshly-mown hay (Graminae) FLAVONOID Functions Main classes of flavonoid ○ Appetite-suppressing properties ○ Flavanone ○ Reducing the impact on grazing animals ○ Anthocyanin ○ Aid in iron uptake from iron-deprived soil ○ Flavonol Examples ○ Proanthocyanin ○ Coumarins ○ Flavanol Esculetin ○ Isoflavone Osthole ○ Flavone Umbelliferone Diverse group of polyphenolic compounds Scopoletin BIO 191: PLANT ADAPTATION AND SURVIVAL 4 PLANT ADAPTATION AND SURVIVAL BIO 191 FIRST SEMESTER | ACADEMIC YEAR 2024-2025 | MR. JEREMIAH ESTRADA Isoflavonoids Deposited on the surface waxes of the plant (UV protection) or stored in the vacuole Biologically active Derivatives were referred to as “phytoestrogens” Functions Almost exclusive to Fabaceae (Legume family) ○ Defense Against Herbivores: Tannins are toxic or Have biological effects via the estrogen receptor unpalatable to many animals, protecting the plant from Has antimicrobial (phytoalexins) and anti-herbivory properties being eaten. Examples ○ Pisatins ○ Protection Against Microbes: Tannins have antimicrobial Produced by Pisum sativum (peas) properties, helping plants resist fungal and bacterial Kills the fungus infections (phytoalexin) Stops spread of infection ○ UV Protection: Tannins may also protect plant tissues ○ Daidzein from UV radiation, which can be harmful in high Produced by Glycine max (soybean) amounts. Defense against pathogenic attacks ○ Inhibiting Seed Germination of Competitors: Some Signal carriers plants release tannins into the soil to inhibit the growth ○ Coumestrol of nearby competing plants, a phenomenon called Produced by Trifolium sp. (clovers) allelopathy. Binds to estrogen receptors Tannin denature and precipitates protein Causes fertility problems ○ Consuming tannin-rich foods or drinks results in dry ○ Rotenone sensation in the mouth Acts as potent insecticide Tannins bind to the proteins in our saliva, Odorless, colorless, crystalline isoflavone which reduces its lubrication and causes a Example rough, dry feeling. Derris elliptica (Tuba - leguminous) Pros and Cons of consuming tannin Lonchocarpus utilis (Barbasco - ○ Pros leguminous) In moderate amounts, they have antioxidant Function and anti-inflammatory properties Potent insecticide protect against Used as fish poison certain types of cancer Inhibits oxidative phosphorylation cardiovascular disease (ETC) microbial infections Toxicity is low in mammals because it is rapidly ○ Cons metabolized in the gut Lead to gastrointestinal discomfort Flavonols Nausea Inhibit iron absorption Group of plant compounds known for their antioxidant properties Decrease the digestibility of some dietary and various health benefits. proteins Structure HOW TO REDUCE TANNIN CONTENT? ○ Two Rings: They have two ring-like structures called ○ Red wine taste is frequently improved by reducing its aromatic rings free tannin content through consumption of protein-rich ○ Connecting Chain: These rings are linked by a chain of foods like cheese and meat three carbon atoms. ○ Milk is added to tea drinks to reduce the free tannin ○ Special Feature: The key thing that makes flavonols content, making tea more palatable special is a -OH group (hydroxyl group) that is attached ○ Grape and banana fruits lose their tannin content as to one part of the structure (the 3-position) of the they ripen, allowing them to be eaten for seed dispersal connecting ring. Common flavonols include Classification of Tannins ○ Quercetin Found in Zingiber officinale (Common ginger) Gallotannins ○ Kaempferol ○ Quercus infectoria (Aleppo oak) Found in Kaempferia galanga (Sand ginger) ○ Rhus chinensis (Chinese nutgall) Ellagitannins ○ Myricetin ○ Rubus sp. (blackberries) ○ Fisetin ○ Faragaria x ananassa D. (strawberries) Photoprotective functions ○ Punica granatum L. (pomegranates) ○ Reduce the amount of UV-B penetration in mesophyll Complex tannins cells Condensed tannins ○ As antioxidants, protect the cells from free-radical ○ Schinopsis lorentzii (Quebracho wood) damage ○ Acacia mollissima (mimosa bark) ○ Vitis vinifera (grape seeds) TANNINS ○ Pine barks ○ Spruce barks There are two types of tannins NOTE: Complex tannins and condensed tannins are the most ○ Hydrolyzable tannins (from Shikimate Pathway) common and easy to extract from legumes, trees and shrubs ○ Condensed tannins (from Phenyl Propanoid Pathway) Complex phenolic-based compounds having bitter taste Frequently present in: ○ Fruits Vitex vinifera (grapes) Musa sp.(bananas) ○ Leaves Camellia seinensis (tea) ○ Bark of some trees (e.g. oak and birch) Produced in high quantities in Fabaceae plants BIO 191: PLANT ADAPTATION AND SURVIVAL 5 PLANT ADAPTATION AND SURVIVAL BIO 191 FIRST SEMESTER | ACADEMIC YEAR 2024-2025 | MR. JEREMIAH ESTRADA Causative agent of Jamaican vomiting sickness NITROGEN-CONTAINING SECONDARY METABOLITES Causes seizures, coma, and sometimes death Leads to extreme hypoglycemia when ingested by inhibiting the Closely resemble the protein amino acids metabolism of fatty acids = depleting glucose and hepatic glycogen Mistakenly incorporates into protein synthesis levels Produces DEFECTIVE enzymes and KILL the herbivore Example Examples ○ Blighia sapida (unripe ackee fruit from ackee tree) ○ Alkaloids ○ Litchi chinensis Sonn. (unripe lychee) ○ Cyanogenic glycosides ○ Glucosinolates CYANOGENIC GLYCOSIDES ○ Non-protein amino acids Sugar-containg metabolites NON-PROTEIN AMINO ACIDS Produces hydrogen cyanide (HCN) upon hydrolysis ○ HCN is a gaseous compound Maybe directly toxic or maybe anti-metabolites (substances that ○ Lighter than air interfere with normal metabolic processes in cells by mimicking or ○ Explosive blocking the use of essential metabolites) ○ Very common everywhere Amino acids other than the 20 amino acids incorporated in protein ○ Colorless (~900) Highly toxic to most living organisms Can be found in Function ○ Leguminosae ○ Inhibits the electron transport system by binding to ○ Liliaceae cytochromes ○ Sapindaceae halts ATP production ○ Cycadaceae oxygen deprivation at the cellular level ○ Compositae Examples ○ Rubiaceae ○ Manihot esculenta (Cassava) ○ Lecythidaceae ○ Sorghum bicolor (Sorghum) Have roles in biosynthesis and neurotransmitter transport ○ Stone fruits Examples Peach: Prunus persica ○ l-canavanine Cherry: Prunus avium ○ γ-aminobutyric acid Plum: Prunus domestica ○ DL-β-aminobutyric acid ○ Bambusa vulgaris (Bamboo roots) ○ l-3, 4-dihydroxyphenylalanine ○ Macadamia integrifolia (Macademia nuts) ○ 5-hydroxy-l-tryptophan ○ Linum usitatissimum (Flaxseed) ○ 5- hydroxytryptamine (serotonin) ○ Prunus dulcis (Almonds) ○ indole-3-acetyl-aspartic acid Amygdalin is a type of cyanogenic glycoside found in apricots and ○ P-aminophenylalanine almonds ○ l-azetidine-2-carboxylic acid 1. β-glycosidase breaks down amygdalin into two parts: Canavanine a. Maltose (a sugar) b. Hydroxynitrile (a molecule containing cyanide) Non-proteinogenic amino acid found in leguminous plants (e.g. 2. Hydroxynitrile lyase, acts on hydroxynitrile, further beans, clover, alfalfa) breaking it down into: Function a. Cyanide (HCN), which is toxic ○ Analogous to arginine b. A neutral compound (not toxic) ○ Affects regulatory and catalytic reaction of Other examples of Cyanogenic glycosides arginine metabolism ○ Dhurrin arginine uptake Sorghum Formation of structural components Bamboo shoots Other cellular processes Other grasses ○ Stores in seeds ○ Prunasin To protect from pathogens and biotic Cherry laurel water predators Primary metabolite of amygdalin ○ Protective allelochemical ○ Linamarin a natural defense against herbivores Cassava ○ Examples Lima beans Canavalia Linseed oil Vicia ○ Lotaustralin Medicago sativa (seeds of Alfalfa) ○ Taxiphyllin Mimosine or Leucenol Toxic non-protein amino acid Cyanide Main role is often to protect plants from herbivores and other threats by disrupting biological processes Toxicity ○ Inhibits DNA replication ○ Inhalation around 100 ppm of cyanide can be fatal in ○ Toxic to ruminants HALF TO ONE HOUR Examples ○ 300 ppm can be fatal within minutes ○ Mimosa pudica (senstive plant) ○ Ingestion of about 40 mg to 100 mg in a 7kg adult is the ○ Leucaena leucocephala (ipil-ipil) reported lethal dose 1-4% of its dry weight are mimosine or Mechanism of Action leucenol ○ HOW DOES CYANIDE AFFECT ETC Found in leguminous species and the genus Leucaena Cyanide blocks the last step in the ETC. This prevents oxygen from being used, halting Hypoglycin A energy (ATP) production. Non-proteinogenic amino acid The body switches to anaerobic energy Has a role as a phytotoxin and a plant metabolite production, causing lactic acid buildup. Toxic if ingested BIO 191: PLANT ADAPTATION AND SURVIVAL 6 PLANT ADAPTATION AND SURVIVAL BIO 191 FIRST SEMESTER | ACADEMIC YEAR 2024-2025 | MR. JEREMIAH ESTRADA ○ Produce cellular hypoxia, by binding to ferric iron that is PLANT LECTINS present in cytochrome oxidase system ○ Lectin-Receptor Binding: Lectins bind to carbohydrate ○ WHAT DOES CYANIDE DO? structures on immune cells, triggering intracellular Blocks aerobic respiration signaling. Normally O2 binds to the Fe2+ within ○ Phagocytosis: Lectins enhance phagocytic activity by the cytochrome but when cyanide is facilitating the recognition of pathogens or dead cells. ingested it binds to the same Fe2+ ○ Cytokine Release: Lectin binding activates immune cells blocking O2 = H2O and ATP is not to release pro-inflammatory cytokines, like TNF-α, IL-6, generated. and IL-1β. Blocks energy production ○ Nitric Oxide Production: Lectins stimulate NO ○ Cellular hypoxia production via iNOS in macrophages, helping to destroy Cells starve for oxygen and die pathogens and regulate immune responses. No amount of oxygen can overcome the deficit ○ Immune Activation: Lectins can mimic PAMPs and in affected cells activate TLRs, promoting innate immune responses. Shift to anaerobic metabolism Plant Lectins and Their Specificities: "Con VFL and Abrin Play Ricin Respiratory Electron Transport Chain Inhibitors Jams So Well" ○ Rotenone ○ Concavanalin A (Con A) Inhibits Complex I by blocking electron transfer Binding specificity: Mannose from NADH to ubiquinone (CoQ), preventing Source: Canavalia ensiformis (Jack bean) the rest of the chain from functioning. ○ Malonate ○ Leucoagglutinin (VFL) Acts as a competitive inhibitor of Complex II by Binding specificity: Mannose mimicking succinate, blocking the oxidation of Source: Vicia faba (Broad bean) succinate to fumarate in the Krebs cycle. ○ Abrin ○ Antimycin-a/Amytal Binding specificity: Galactose Inhibits Complex III by blocking electron Source: Abrus precatorius (Rosary pea) transfer from ubiquinol (QH2) to cytochrome c, disrupting the flow of electrons. ○ Phaseolus agglutinin (PHA) ○ Cyanide/Carbon monoxide/Hydrogen sulfide Binding specificity: Galactose Inhibits Complex IV (cytochrome c oxidase) by Source: Phaseolus vulgaris (Red kidney bean) binding to the iron in cytochrome a3, ○ Ricin preventing oxygen from accepting electrons, Binding specificity: Galactose halting ATP production. Source: Ricinus communis (Castor oil plant) ○ Oligomycin ○ Jacalin Inhibits ATP synthase (Complex V), preventing the flow of protons back into the Binding specificity: Galactose mitochondrial matrix, which stops ATP Source: Artocarpus integrifolia (Jackfruit) generation from ADP. ○ Soybean agglutinin (SBA) GLUCOSINOLATES Binding specificity: N-acetylglucosamine Source: Glycine max (Soybean) Toxic sulfur and nitrogen-containing sugar sulfate ○ Wheat germ agglutinin (WGA) Occur mainly in the bassicaceae or mustard family Present in mustard, cabbage, and horseradish Binding specificity: N-acetylglucosamine Plant defense against pests and diseases Source: Triticum vulgaris (Wheat germ) Hydrolysis of glucosinolates Ricin ○ When plant tissue is damaged (e.g., by chewing or ○ Most poisonous naturally occurring substances known cutting), the enzyme myrosinase is released. ○ Derived from beans of castor oil plant ○ Myrosinase breaks down glucosinolates into several Castor oil used in brake and hydraulic fluid compounds: ○ Can be fatal when inhaled, ingested or injected Isothicyanate ○ Toxic to cells Nitrile ○ Traces of Ricin have been found in Afhan caves Thiocyanate LECTINS ALKALOIDS Sugar-binding proteins that AGGLUTINATE CELLS or PRECIPITATE Usually contains nitrogen atoms and a heterocyclic ring PROTEINS with long carbohydrate conjugates Simple or complex Frequently detected in Low molecular weight nitrogen-containing compounds ○ Leguminosae Alkaline and freely water-soluble ○ Euphorbiaceae Derived from Binds to carbohydrates/polysaccharides = antimicrobial activity ○ Amino acids Used in medicine as cancer biomarkers ○ Purines and pyramidines ○ Recognizing malignant tumor cells Physiologically active and toxic to mammals Function Play a role in plant defense ○ Bind to carbohydrates Types of Alkaloids ○ Precipitate polysaccharide True alkaloids ○ Agglutinate cells ○ Have heterocyclic ring with nitrogen ○ Induce death in cancer cells through ○ E.g. nicotine Apoptosis Proto alkaloids Autophagy ○ Does not have heterocyclic ring with nitrogen WHAT HAPPENS WHEN LECTINS AND RBCS MIX? ○ E.g. colchicine from tyrosine ○ Hemagglutination occurs, which is the clumping or Pseudo alkaloids agglutination of RBCs. ○ Have heterocyclic wing with nitrogen but is not derived from amino acids ○ E.g. solanidine (steroid) BIO 191: PLANT ADAPTATION AND SURVIVAL 7 PLANT ADAPTATION AND SURVIVAL BIO 191 FIRST SEMESTER | ACADEMIC YEAR 2024-2025 | MR. JEREMIAH ESTRADA Classes of Alkaloids ○ Cause of death by the philosopher Socrates ○ Piperdine alkaloids Phenyalanine-derived Alkaloid ○ Pyrrolidine/tropane alkaloids ○ Pyridine alkaloids ○ Ephedrine ○ Catecholamine and tetrahydroisoquinolines Stimulant that acts on the CNS ○ Opiates Dilates the bronchial tubes ○ Phenylalanine-derived Elevates blood pressure ○ Indole alkaloids Increases HR ○ Quinoline alkaloids Gives jolt of energy ○ Purine alkaloids In medicine, it prevents low blood pressure during anesthesia Pyrrolidine Alkaloid Comparable actions to adrenaline Cocaine Can be found in plants under the genus ○ Tropane alkaloid that acts as a central nervous system Ephedra stimulant Opiates ○ Blocks dopamine transporter -> higher dopamine in synaptic cleft = euphoria and arousal Morphine ○ Function ○ Natural alkaloid that is derived from resin extracts from Stimulates the mesolimbic pathway in the seeds of the opium poppy (Papaver somniferum) brain ○ Function Intense feeling of happiness Analgesic effects Sexual arousal Used in clinical medicine to treat pain Loss of contact with reality Binds to the opioid receptors within the CNS Agitation Interrupting the way nerves signal Fast heart rate pain Sweating Heroin Dilated pupils ○ Morphinane alkaloid ○ Powder form is call cocaine hydrochloride Morphine bearing 2 acetyl substituents on the Scopolamine O-3 and O-6 positions ○ Tropane alkaloid ○ Function ○ “Devil’s Breath” Relieve pain ○ Found from all parts of plants of the nightshade family During childbirth (Solanaceae) Heart attack Atropa belladonna Enters the bran then it is converted to Brugmansia spp. morphine to bind rapidly to opioid receptors ○ Function within the CNS Has anticholinergic, antiemetic, and antivertigo ○ Can be found in Papaver somniferum (Opium poppy) properties Quinoline Alkaloid Prevents nausea and vomiting (from motion Quininne sickness) ○ Alkaloid derived from the bark of cinchona tree Antispasmodisc (Cinchona spp.) Used to relieve cramps and spasms ○ Function ○ Stomach Increase appetite ○ Intestines Promotes release of digestive juices ○ Bladder Treats bloating and fullness Antacids Stomach problems Treatment for peptic ulcers Used to treat malaria caused by Plasmodium Blocks acetylcholine on CNS falciparum Plays a role in memory, learning, Kill parasite attention, arousal, and involuntary muscle movemet Indole Alkaloid Pyridine Alkaloid Vinblastine ○ Found in the Madagascar periwinkle plant (Catharanthus Nicotine roseus) formerly Vinca rosea ○ Naturally occurring alkaloid in the nightshade family ○ Function (Solanaceae) Treat cancer Nicotiana tabacum Breast Duboisia hopwoodii Testicular ○ Function Neuroblastoma Stimulant and anxiolytic Hodgkin’s lymphoma reduces anxiety; stored in vacuoles Non-small-cell lung cancer act as defense for predation Bladder cancer ○ Bloodstrem → Adrenal gland → release of adrenaline → Brain increases blood pressure, breathing and HR Melanoma Piperidine Alkaloid Block mitosis in cancer cells Coniine ○ Mechanism of action ○ Poisonous chemical compound from poison hemlock Binds to tubulin, inhibiting microtubule ○ Found in all parts of Conium maculatum (Poison assembly hemlock) Tubulin provides cell shape ○ Neurotoxic alkaloid Purine Alkaloids Causes paralysis, Caffeine Seizure, ○ CNS-stimulant present in coffee (Coffea spp.) and tea And death (Camellia sinensis) ○ Greeks used this to execute criminals or political ○ Function prisoners BIO 191: PLANT ADAPTATION AND SURVIVAL 8 PLANT ADAPTATION AND SURVIVAL BIO 191 FIRST SEMESTER | ACADEMIC YEAR 2024-2025 | MR. JEREMIAH ESTRADA Stimulates CNS, heart and muscles ○ MITOCHONDRIA Increases breathing Role of Compatible Solutes: Compatible Increases HR solutes like glycerol help maintain Increased mental alertness and physical energy mitochondrial integrity and function during Theobromine stress. They can also assist in stabilizing ○ Principal alkaloid of the cacao bean mitochondrial proteins and membranes. ○ Found in Theobroma cacao ROS Production: Mitochondria are a major ○ Consumed in cocoa and chocolate beverages and various source of ROS during aerobic respiration, forms of chocolate-based foods primarily generating superoxide (O₂⁻). ○ Slightly soluble with a bitter taste Compatible solutes can help protect ○ Function mitochondrial components from oxidative Increases heat rate damage by scavenging ROS and maintaining Causes sleeplessness osmotic balance. Keep you awake and alert ○ ENDOPLASMIC RETICULUM COMPATIBLE SOLUTES AND OSMOPROTECTANTS Role of Compatible Solutes: The endoplasmic reticulum, involved in protein folding and synthesis, can benefit from compatible solutes COMPATIBLE SOLUTES that stabilize proteins under stress conditions, Low MW compound that do not interfere with normal biochemical preventing aggregation and misfolding. reaction ROS Production: The ER can generate ROS, Function particularly during stress responses, affecting ○ Protects structure and supports osmotic balance protein quality control. Compatible solutes Facilitates water retention in the cytoplasm may help mitigate ROS effects by maintaining Allow sodium sequestration to proper protein structure and function. vacuole/apoplast ○ PLASMA MEMBRANE ○ Can accumulate to a high level without disturbing Role of Compatible Solutes: Compatible intracellular biochemistry solutes like sorbitol and mannitol help ○ Minimal effect on pH or charge balance of cytosol maintain plasma membrane integrity and ○ Preserve enzyme activity fluidity during osmotic stress. They also ○ Synthesis is usually triggered by stress protect against ROS-induced lipid peroxidation, Examples which can compromise membrane function. ○ Polyols ROS Production: ROS can damage the plasma Mannitol membrane, leading to lipid peroxidation and Pinitol loss of permeability. Compatible solutes can Sorbitol scavenge ROS and protect lipid bilayers, ○ Carbohydrates ensuring cellular homeostasis. Trehalose ○ MICROBES Sucrose Role of Compatible Solutes: Microbial ○ Nitrogen-containing compounds communities in the rhizosphere and within Amino acids (proline) plant tissues often produce compatible solutes Amides like trehalose and glycerol to cope with Quaternary ammonium compounds osmotic stress and protect against oxidative (glycinebetaine) damage. Polyamines ROS Production: Microbial metabolism can Functions of Compatible Solutes On generate ROS, affecting both microbial and plant health. Compatible solutes can help Osmoprotectants microbes survive oxidative stress by stabilizing ○ Protects cellular structures by interacting with cellular structures and scavenging ROS, membranes, protein, comploxes, or enzymes promoting symbiotic relationships with plants. ○ Protects macromolecules from the effects of increasing ionic strength ○ Maintains cellular pH PHYTOHORMONES ○ Scavenging or detoxification of free radicals and reactive All chemical produced by plants that regulate oxygen species ○ Cellular activities ○ Examples Division Glycine betaine Elongation Proline Differentiation Reactive oxygen species ○ Pattern formation ○ CHLOROPLAST ○ Organigenesis Role of Compatible Solutes: In chloroplasts, ○ Reproduction compatible solutes such as proline and betaine ○ Sex determination help protect photosynthetic machinery from ○ Responses to biotic and abiotic factors oxidative damage caused by ROS, especially Phytohormones include during high light conditions and environmental ○ Auxin stresses like drought. ○ Cytokinins ROS Production: During photosynthesis, light ○ Gibberillins energy can lead to the formation of ROS, ○ Abscisic acid particularly singlet oxygen (¹O₂) and ○ Ethylene superoxide (O₂⁻). Compatible solutes stabilize ○ Brassinosteroids chloroplast membranes and proteins, helping ○ Salicylates to maintain function and prevent ○ Strigolactones photoinhibition. ○ Jasmonates BIO 191: PLANT ADAPTATION AND SURVIVAL 9 PLANT ADAPTATION AND SURVIVAL BIO 191 FIRST SEMESTER | ACADEMIC YEAR 2024-2025 | MR. JEREMIAH ESTRADA Function ○ Regulate all stages of the plant life cycle ○ Helps plants cope with stress throughout their life Auxin FUNCTION ○ Stimulates cell elongation ○ Involved in phototropism, gravitropism, apical dominance, and vascular differentiation ○ Stimulates ethylene synthesis ○ Induces advantitious roots in cutting ○ Xylem differentiation ○ Regulates fruit development (Parthenocarpy) ○ Delays leaf abscission WHERE PRODUCED ○ Meristems of apical buds ○ Embryo of seed ○ Young leaves There are two types ○ Natural Indoleacetic acid (IAA), IBA ○ Synthetic Naphthalene acetic acid (NAA), 2,4-D BIO 191: PLANT ADAPTATION AND SURVIVAL 10