A precursor of thiamine in bacteria. Produced from glyceraldehyde-3-phosphate and pyruvate, catalyzed by DXS. Combines with dehydroglycine to form thiazole phosphate carboxylate, catalyzed by THISG.

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A benzoic acid benzenoid.

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Produced from phytyl diphosphate and homogentisic acid by homogentisate prenyl transferase in tocopherol synthesis. May be converted into β-tocopherol by VTE1 and VTE4. Methylated into 2,3-dimethyl-5-phytyl-1,4-benzoquinone (DMPBQ) by the methyltransferase VTE3, which may be subsequently converted into α-tocopherol by VTE1 and VTE4.

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Produced by 3-ketoacyl-ACP reductase. Dehydrated by 3-hydroxyacyl-ACP dehydratase.

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Acetoacetyl-ACP

A four-carbon intermediate formed by KAS III. Reduced by 3-ketoacyl-ACP reductase.

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"Skunky" thiol

Causes the off-flavour in "lightstruck" beer that has been left in the sun. Has a stinky smell. Forms when beer is irradiated with visible light, 350 - 500 nm. A few nanograms per litre are enough to make a beer unpalatable. Isohumulones and riboflavin are pivotal in its formation: it forms from triacylmethyl radicals. Has a similar structure to butanethiol.

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A 3-carbon compound. The first product of CO₂ fixation. Discovered in 1916 by Calvin et al using 2-dimensional paper chromatography and autoradiography.

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Produced from tyrosine in a deamination (tyrosine aminotransferase, producing 4-hydroxyphenylpyruvate), and a decarboxylation (4-hydroxyphenylpyruvate decarboxylase). A precursor of isoquinoline alkaloids. Condensed with dopamine to form noroclaurine.

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Converted into hydroxymethyl-2-pyrimidine phosphate by ThiC. Requires tetrahydrofolate for its synthesis. An intermediate in purine synthesis.

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The main homolog of tocopherol found in supplements and in European diets where the main sources are olive and sunflower oil, which can be up to 90% α-tocopherol. Predominant in leaves. Can physically quench and deactivate singlet oxygen by donating an electron; a charge transfer exciplex forms which undergoes intersystem crossing that dissociates, deactivating singlet oxygen. Other antioxidants such as ascorbate and glutathione convert it back to α-tocopherol.

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A tetraterpene. Found in golden rice. Accounts for 25 - 30% of photosynthetically active tissues. The precursor of xanthophylls. In animals it is used to form vitamin A.

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A main terpene emitted from tomato trichomes. A sesquiterpene. Can stain hands green when handling tomatoes.

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A main terpene emitted from tomato trichomes. A monoterpene. Can stain hands green when handling tomatoes.

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A sitosterol. The most efficient plant sterol. Found in avocados, nuts, and vegetable oils.

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The main homolog of tocopherol found in American diets where the main sources are soybean and corn oil. The most potent antioxidant and free radical remover of all vitamin E homologs. It has a strong anti-inflammatory activity, related to inhibition of carcinogenesis. Predominant in seeds.

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ATPases Associated with a variety of cellular Activities

A family of molecular chaperones. Includes rubisco activase.

A diterpene.

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The initial carbon precursor of fatty acids, the building block for assembly of long chain fatty acids in a series of repeated reactions. It cannot cross membranes by diffusion and there are no known transporters; instead it is shuttled by pyruvate.

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Uses 2 ATP equivalents to regenerate acetyl-CoA from acetate in an anapleurotic reaction, driving serine acetyltransferase and OAS(thiol)lyase.

CoA + acetate + ATP → acetyl CoA + AMP + PPi

Formerly called vitamin B₄. It was considered a vitamin until it was discovered that it was not vital for human life.

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A prenylated acylphloroglucinol. An α-acid found in hops. Synthesized from isoleucine via 2-methylbutyryl-CoA.

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A prenylated acylphloroglucinol. A β-acid found in hops. Synthesized from isoleucine via 2-methylbutyryl-CoA.

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A monoterpenoid indole alkaloid. An anti-hypertension drug used in the treatment of high blood pressure. A selective antagonist of α1-adrenergic receptors, which mediate smooth muscle contraction.

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Transaminase

Redistributes N to a range of amino acids, from glutamate and glutamine. Catalyzes the transfer of an amino group from the α-carbon of an amino acid to the α-carbon of a keto acid in a freely reversible reaction. Coenzyme pyridoxal 5'-phosphate is needed for all reactions. There are 60 aminotransferases in Arabidopsis, catalyzing amino transfer of all common amino acids, and some intermediary amino acids not found in proteins. Most plants pass N through glutamate, and most aminotransferases use glutamate as an N donor, leading to large amounts of 2-oxoglutarate, converted back to glutamate through the GS-GOGAT cycle.

A pyrrolizine alkaloid found in lupines. Takes up 3% of the weight of lupine seeds. Causes crooked calf disease in grazing livestock.

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An isoquinoline alkaloid found in lupines. Takes up 3% of the weight of lupine seeds. Causes crooked calf disease in grazing livestock.

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A flavone flavonoid. Found in alfalfa.

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A major N transporter in grapes. Has a net positive charge. A precursor of tropane alkaloids. Converted into putrescine by arginine decarboxylase.

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Produced from prephanate by PPA-AT. Converted into tyrosine by arogenate dehydrogenase, and converted into phenylalanine by arogenate dehydratase.

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Can be metabolically engineered.

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Vitamin C

Precursor is mannose and galactose. Found in citrus and leafy vegetables.

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An amino acid in the aspartate family. Used to form purines, pyrimidines, cytokinin, and alkaloids.

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A tropane alkaloid found in henbane (Hyoscyamus niger), mandrake, deadly nightshade, jimson weed, and Atropa belladonna, which means "beautiful woman" in Italian (this is also the deadly berries from Hunger Games). Used by Queen Cleopatra to dilate her pupils, to seem more alluring and beautiful. A diastereomeric mixture of _D- and _L-hyosamine. Blocks acetylcholine and muscarinic receptors.

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A defensive compound benzenoid.

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"Foolish seedling"

A disease in rice caused by the fungus Gibberella fujikuroi. The fungus produces gibberellin, which fools the plant into growing too tall and too slender, killing the plant.

Almond oil

A volatile phenolic produced from benzoic acid. Smells sweet, like almonds. Found in almonds and jasmine. A benzenoid. A key intermediate in the non-β-oxidative pathway.

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Benzoic acid derivative

The second largest class of plant volatile compounds. Primarily synthesized to attract pollinators, derived exclusively from phenylalanine. Includes benzoic acids, primarily metabolites, volatile organic compounds, and defensive compounds. The first committed step is catalyzed by _L-phenylalanine ammonia-lyase. A simple phenolic.

A benzoic acid benzenoid. Can be modified into many things.

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A volatile organic compound benzenoid. Found in perfume.

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A volatile organic compound benzenoid. Synthesized from benzoic acid. Smells sweet, like balsam. Found in balsam blossoms and hyacinth.

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The key intermediate in the β-oxidative pathway.

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An isoquinoline alkaloid. An anti-microbial agent. Found in barberry. Synthesized from noroclaurine with (S)-reticuline.

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Vitamin B₇.

A prosthetic group of acetyl-CoA carboxylase, covalently bound to biotin carboxyl carrier protein subunit. Acts as a flexible arm, shifting CO₂ from biotin carboxylase to α- or β-carboxyltransferase subunits. Important for growth of hair and nails. A protein in egg yolks will bind to it, making it impossible to absorb during digestion. However, this protein is destroyed when you cook eggs. Precursors are alanine and pimeloyl-CoA. Found in leafy vegetables and peanuts.

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A brassinosteroid. Synthesized from squalene.

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Skunk mercaptan

Has a similar structure to MBT. It produces the smell of skunk.

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The saturated product of enoyl-ACP reductase. A four carbon-ACP compound.

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C4 metabolism

Can occur in a single cell in some land plants, with dimorphic chloroplasts in different cytoplasmic compartments; fixes CO₂ with PEP near the centre, and concentrates CO₂ near the edges of the cell. Normally associated with Kranz anatomy in most land plants; there is higher resistance of CO₂ in the leaf, allowing for better use of CO₂. Concentrate CO₂ in photosynthetic cells, up to 1,200 ppm. Initial fixation product in C4 plants is a 4-carbon acid, oxaloacetate. There are three variations, based on product transported from the bundle sheath cell, and the pathway for regeneration of PEP. Includes NADP-ME, NAD-ME, and PEP-CK.

A bicyclic sesquiterpene. Found in cade juniper.

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A hydrocinnamic acid, with an OH at R1, and an H at R2.

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1,3,7-trimethylpurine-2,6-dione

A purine alkaloid produced by Coffea arabica. Kills nearly all larvae of tobacco roundworm, Manduca sexta, within 24 hours, at very low doses. Inhibits the phosphodiesterase that hydrolyzes cAMP. Produced as a defence against herbivores, and a potent germination inhibitor. Antogonized adenosine receptors, preventing drowsines. There are wild coffee species which lack caffeine, but there are reproductive barriers for crossing it into commercially grown coffee. Mutations occured in the gene coding for caffeine synthase, causing theobromine accumulation.

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C3 pathway

Photosynthetic C reduction cycle

Reductive pentose phosphate cycle

Found in all plants. Calvin et al used radio-labelled carbon, ¹⁴C, and Chlorella green algae, and followed movement of ¹⁴C with a kinetic approach. Filtered the thermal irradiation that illuminated the algae. Separated the chemicals produced at various times after illumination, using 2-dimensional paper chromatoraphy. There are three enzymes, and four reactions unique to the cycle. Enzymes include aldolase, rubisco, transfunctional catalase (TK), sedoheptulose-1,7-bisphosphate, and phosphoribuklokinase. Three phases: carboxylation-equilibrium (favours 3-PGA formation), reduction-formation of triose-P (GAP), and regeneration-formation of ribulose bisphosphate. Reactions occur in the stroma. Regulated to balance carbon and light reactions, and inhibit futile cycles in the darkness (running at the same time as the OPPP). Regulated by: modulation of enzyme activity by the ionic and solute environment of the stroma, occurs in seconds; post-translational regulation of transition between active and inactive forms of CBB cycle enzymes by ferredoxin-thioredoxin system and rubisco activase, occurs in seconds to minutes; and modulation of gene expression at the transcriptional and translational levels, occurs in minutes to days. Optimum pH for enzymes is 8; found in the stroma in the light. Mg^2- is a cofactor in many enzymes, and a charge balancer in the thylakoid lumen. Provides intermediary metabolites for synthesis of nucleotides (ribose 5-phosphate), terpenoids (GAP), and the shikimate pathway (erythrose 4-phosphate). Used to be thought to be the only carbon fixation cycle.

A common plant sterol. Found in banana, pepper, and pomegranate.

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A cannabinoid.

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A cannabinoid.

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A major cannabinoid. A prenylated polyketide. Does not cause psychoactive effects, but does give anti-inflammatory, anti-analgesic, anti-anxiety, and anti-nausea effects to marijuana. The major cannabinoid in hemp. Synthesized from cannabigerolic acids by CBDAS and thermal conversion during smoking.

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A cannabinoid.

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A cannabinoid.

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A cannabinoid.

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Synthesied from olivetolic acid by adding GPP with a prenyltransferase. May be converted into tetrahydrocannabinol by THCAS and thermal conversion during smoking. May be converted into cannabidiol by CBDAS and thermal conversion during smoking.

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A cannabinoid.

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A cannabinoid.

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A saturated fatty acid.

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A saturated fatty acid.

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A phenolic found in red and black peppers.

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Synthesized from squalene.

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Diphosphatidylglycerol

A phospholipid. The head group is phosphatidylglycerol. Net charge is -2 at pH 7. Found in animals, not in plants. Synthesized in the CDP-DAG pathway of the eukaryote pathway. A second phosphatidic acid group is added to phosphatidylglycerol to form CL. Found in animal cells.

A bicyclic monoterpene. Smells woody and pungent.

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Vitamin A

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Vitamin A

A fat-soluble vitamin, an isoprenoid. Important for photosynthesis; absorbs heat and quenches singlet oxygen. Synthesized from geranylgeranyl pyrophosphate. Has breakdown products. With a few exceptions, animals cannot synthesize them, and must include in their diet essential retinoids including vitamin A. There are 750 known, grouped into carotenes and xanthophylls. Name comes from the carrot, where they accumulate in roots. Usually found in the shoot of the plant. Gives colour to flowers, fruits, and seeds. Accumulates in specialized plastids, chromoplasts, as well as in chloroplasts and plastoglobuli. Embedded in the thylakoid membrane. Photosynthetically active tissues accumulate 45% lutein, 25 - 30% β-carotene. 10 - 15% violaxanthin, and 10 - 15% neoxanthin. Colours become visible in leaves when chlorophyll is broken down in the autumn.

Daucus carota

Accumulates carotenoids in its taproot. Carotenoids are named for this plant.

(C₆H₁₀O₅)_n

A polymer of (1 → 4) linked glucose molecules. The C1-hydroxyl group is β. The principle scaffolding component of the cell wall. Exists in microfibrils. The most abundant plant polysaccharide on Earth. Represents 15 - 30% of the primary cell wall. 10¹¹ tonnes are synthesized and destroyed annually. Synthesis occurs on the face of the plasma membrane, with cellulose synthase. Can be turned into biofuel, but this is limited by lignin.

A sphingolipid. No headgroup. The X group is a single H.

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Tetrahydroxychalcone

Produced by chalcone synthase. It is the precursor of flavonoids and cannabinoids. Undergoes a series of isomerizations, hydroxylations, desaturations, and reductions to form flavonoids.

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A phenolic found in cloves.

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A phenolic found in coffee beans.

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Synthesized from GGPP. A lipid. Accounts for 25% of total plant lipids.

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Vitamin D

Fat-soluble vitamin. An isoprenoid. Precursor is isoprenoids. Found in soybeans, alfalfa, cotton, mushrooms, fish, foritfied milk, and other foods. It is made in few plants. Helps in absorption of metals and cofactors during digestion. A cholesterol derivative. Can be synthesized in animals with sunlight exposure; cholesterol reacts with light. 

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Synthesized from squalene.

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Used to form aromatic amino acids, situated at the branchpoint of their pathways. One branch (chorismate mutase) leads to phenylalanine and tyrosine, while the other results in tryptophan formation. A precursor of the pABA moiety of folate, in the plastid.

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A phenolic found in cinnamon bark. 

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A prenyltransferase that adds the C5 IPP in cis configuration. Results in formation of neryl pyrophosphate. Includes NPP synthase. Plants have many enzymes. Grouped into four clades:

1. Dicots and monocots

2. Dicots and monocots

3. Bacteria, used for cell wall synthesis

4. Dolichol synthesis

An acyclic monoterpene. Smells like lemon.

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Vitamin B₁₂

It is not produced by plants.

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A tropane alkaloid found in the leaves of the coca plant. Blocks dopamine transporter on the synaptic clef. A benzenoid.

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Theobroma oil

Contains 18:1, 18:0, and 16:0 fatty acids: palmitic, stearic, and oleic acids. Mostly saturated fats with a low melting point, giving a melt-in-your-mouth sensation to chocolate. Cocoa butter separated from chocolate liquor contains stearic and palmitic acids.

An isoquinoline alkaloid. A cough suppressant. Found in opium poppy. Synthesized from noroclaurine with (R)-reticuline.

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Derived from pantothenate (vitamin B₅), ATP, and cysteine. Used by 4% of enymes.

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A prenylated acylphloroglucinol. A α-acid found in hops. Synthesized from valine via isobutyryl-CoA.

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A prenylated acylphloroglucinol. A β-acid found in hops. Synthesized from valine via isobutyryl-CoA.

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An aldehyde which is derived from the CoA-ester of ferulic acid. The precursor of coniferyl alcohol.

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The G unit monolignol. Produces guaiacyl lignin. Derived from coniferaldehyde.

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A poisonous alkaloid found in hemlock, Conium maculatum. Socrates was sentenced to death, and he chose to die by consuming an extract of hemlock containing coniine.

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An aldehyde which is derived from p-coumaroyl-CoA. The precursor of p-coumaryl alcohol.

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Benzopyranone

A simple phenolic. A widespread family of plant metabolites. There are over 1,500 in over 800 species. Role is in defence: has antimicrobial, antifeeding, and germination inhibitory properties. Ingestion can cause massive internal bleeding in mammals. Found in clovers. Includes warfarin and furanocoumarin. Formed from p-coumaric acid via hydroxylation, and isomerization with ring closure.

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A flavonoid. Found in rose, Rosa. Gives red colour to roses and berries.

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A key intermediate in sterol synthesis. An epoxine. Forms from cyclization of squalene-2,3-epoxine. It is cyclized to form lanosterol, the precursor of cholesterol and ergosterol.

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An S-containing amino acid in the 3-PGA family. Synthesized from serine acetyltransferase and OAS(thiol)lyase, mostly in photosynthetic tissues in the chloroplast. A large portion is used in synthesis of glutathione. Also used to form glucosinolates.

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A substrate of the MEP cytidylyltransferase (MEPC). Contributes to a cytidyl phosphate residue. It is synthesized from nucleotides.

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Fructose-1,6-bisphosphate phosphatase

Converts triose-P into hexose-P. A sucrose synthetic enzyme that is quite complex. Has a non-competitive inhibitor, fructose-2,6-bisphosphate. Produces fructose-6-phosphate. Not needed to produce sucrose in the dark.

3-deoxy-_D-arabino-heptulosonate-7-phosphate synthase

The first enzyme of the shikimate pathway. Condenses erythrose-4-phosphate with PEP, forming DAHP, which is then converted into 3-dehydroquinate by DHQS. Both substrates are formed from carbohydrate breakdown. There are two genes: DAHPS2 is constitutively expressed, and DAHPS1 is stronly induced in response to wounding and pathogen infection.

An anthocyanidin flavonoid. Found in larkspur, Delphinium. Gives a blue colour. Moderate success trying to insert the gene into a white rose, to produce a transgenic blue rose.

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Fatty acid desaturase (FAD)

A way that the fatty acid cycle can end. Introduces double bonds to the acyl chains of saturated fatty acids. Two classes: soluble and integral membrane. At least eight have been identified in Arabidopsis, each differing in their subcellular location, substrate specificity, tissue distribution, and mode of regulation. Formation of the double bond requires 2 electrons. In the plastid these are supplied by ferredoxin generally photosynthetically. In the endoplasmic reticulum they are supplied by NADH via cytochrome B5 reuction. All desaturases in animals, yeasts, and plants are integral membrane proteins except for stearoyl-ACP desaturase.

A main galactolipid. The head group is diagalactose. Synthesized in the DAG pathway of the prokaryote pathway. An additional galactose is added.

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A glycerol backbone with two fatty acids, and a single H at the X group. Synthesized from poly-phosphoinositides. Modulates the activity of protein kinase C. A secondary messenger that triggers several signalling pathways.

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Synthesized from squalene. Found in foxglove. Poisonous; it causes cardiac arrest. It is the poison that James Bond drank in Casino Royale.

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Produced from the fusion of the pABA moiety and the pterin moiety (phosphorylated HMDHP), catalyzed by dihydropteroate synthase (DHPS) in the mitochondria. It is conevrted into tetrahydrofolate by two enzymes.

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A precursor of isoprenoids and terpenes. A 5-carbon compound. It may be isomerized from IPP by IPP isomerase. Combined with malonyl-CoA and BCAA to form humulone.

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Synthesizes diterpenes from C20 geranylgeranyl diphosphate in the plastid. Carries out two types of reactions:

1. Resembles mono- and sesquiterpene synthases: ionization of the diphosphate ester initiates cyclization.

2. Geranylgeranyl diphosphate is protonated at the C14 - C15 double bond, initiating cyclization and forming a stable intermediate, copalyl diphosphate.

An isoprenoid. A polyisoprenoid. An 85-carbon molecule. Synthesized from farnesyl pyrophosphate. An electron carrier.

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Produced from tyrosine by a decarboxylation (tyrosine decarboxylase, producing tyramine), and a hydroxylation. A precursor of isoquinoline alkaloids. Condensed with 4-hydroxyphenylacetaldehyde to form noroclaurine.

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An unsaturated fatty acid. The trans isomer of oleic acid.

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Octadecatrienoic acid

The major fatty acid found in bitter gourd oil.

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The first phase of glucosinolate synthesis. Certain aliphatic and aromatic amino acids are elongated by insertion of methylene groups into side chains. Sequence of this pathway was delineated using in vivo feeding studies and isolation of key intermediates. The parent amino acid is deaminated to form 2-oxo acid, then steps 1 - 3 are repeated 0 - 9 times, adding methylene groups. After each turn of the cycle, the 2-oxo acid may be transaminated and enter core structure assembly. Two carbon atoms are contributed by acetyl-CoA each time, but the COOH group added is lost, so net of one carbon is added each time.

1. 2-Oxo acid is condensed with acetyl-CoA to form 2-malate derivative.

2. 2-Malate derivative is isomerized into 3-malate derivative.

3. 3-Malate derivative undergoes oxidation-decarboxylation to form 2-oxo acid with one more methylene group.

2,3-Trans-enoyl-ACP reductase

Converts trans-butenoyl-ACP into butyryl-ACP.

A diterpene. Used to form gibberellin. Synthesized from geranylgeranyl diphosphate by ent-copalyl diphosphate synthase and ent-kaurene synthase, with copalyl diphosphate intermediate. In fungi these two enzymes are a single bifunctional CPS/KS enzyme.

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A medical alkaloid. Found in Chinese ephedra, Ephedra sinica. An anti-asthma medication.

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A phenolic found in green tea.

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A phenolic found in green tea.

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Vitamin D

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A monoterpenoid indole alkaloid.

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An unsaturated fatty acid.

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A polyketide. A commonly prescribed antibiotic. Isolated from a fungus.

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An intermediate in the CBB cycle and OPPP. Used as a carbon skeleton for amino acids in the shikimate family. Formed from carbohydrate breakdown. Condensed with PEP by DAHP synthase.

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A chemical mutagenizing agent that causes point mutations in genes, specifically causing a transition of a C-G pair into an A-T pair. Ethyl group reacts with guanine, forming the abnormal base 6-O-guanine. DNA polymerase then places a T instead of a C opposite to the 6-O-guanine, causing the transition mutation. Rate of mutation at a given gene is 1 in 5,000 plants: reduces plants needed to screen for mutants by 100 times, with genetially amenable plants such as Arabidopsis thaliana. Arabidopsis seeds are soaked in EMS to mutagenize plants. Used in mutant screening.

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A bicyclic monoterpene. Found in eucalyptus.

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A phenolic found in cloves.

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(E,E)-FPP

A C15 trans-prenyl diphosphate. Synthesized by FPP synthase. A central precursor in isoprenoid metabolism, forming sesquiterpenes, cholesterol, ubiquinone, dolichols, and brassinosteroids. Found in the cytoplasm.

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A hydroxycinnamic acid, with an OCH₃ group at R1, and an H at R2. Its CoA ester is the precursor of coniferaldehyde and coniferyl alcohol.

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Produced from flavin mononucleotide and an ATP-derived AMP moiety, by FAD synthase. An active form of riboflavin. In plants it is an essential cofactor for photosynthesis, mitochondrial electron transport, fatty acid oxidation, photoreception, DNA repair, metabolism of other cofactors and the synthesis of several secondary metabolites. It accepts electrson from all riboflavin redox states: FAD, FADH, and FADH₂.

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Produced from riboflavin by riboflavin kinase. An active form of riboflavin. An essential redox factor. Can be turned into flavin adenine dinucleotide by FAD synthase. Humans can synthesize it from riboflavin. In plants it is an essential cofactor for photosynthesis, mitochondrial electron transport, fatty acid oxidation, photoreception, DNA repair, metabolism of other cofactors, and the synthesis of several secondary metabolites.

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Vitamin B₉

Benefits the neural development of fetuses in pregnant women. Found in spinach and beans. There are C1 units at various oxidation leves, attached to N5 and/or N10. Polyglutamated in vivo. Photolabile. A tripartite molecule: includes pterin moiety and pABA moiety, which as synthesized in the cytosol and chloroplast, respectively, and combined in the mitochondria. Precursor is pABA, pterine, and glutamate. Can exist in five different oxidation states. Converted into tetrahydrofolate in the body.

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Vitamin B₉

From Latin for leaf, "folium". A primary metabolite benzenoid. Discovered by Herschel Mitchell in 1941. First isolated from spinach leaf. Found in green leafy vegetables. Most processed foods in our society are fortified with it. 

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L₈S₈

A form of rubisco. A hexadecamer of 8 large catalytic subunits (L) and 8 small subunits (S). Found in all green plants.

L₂ and L₂₍₅₎

A form of rubisco. Found in some Archaea. Not used in the CBB cycle.

An analog of the intermediate of DXP reductoisomerase, 2-C-methyl-erythrtose-4-phosphate. An inhibitor of DXP redutoisomerase, preventing formation of MEP. Found in protozoa and bacteria, including the plasmodia that causes malaria. It can be targeted to cure malaria.

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A non-competitive inhibitor of cytFBPase. A regulatory metabolite, not an intermediary. Can inhibit cytFBPase at very low concentrations. Synthesized from fructose 6-phosphate by fructose-6-phosphate 2-kinase, and degraded into fructose 6-phosphate by fructose-2,6-bisphosphatase. These enzymes have allosteric effectors, some of which are directly involved in the sucrose synthetic pathway. An activator for the enzymes PP-fructose-6-phosphate kinase, which catalyzes the opposite reaction to cytFBPase, and allows carbon to be funnelled into glycolysis. A key regulator that controls whether C enters the anabolic sucrose synthesis pathway or the catabolic glycolytic pathway.

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Synthesized into fructose-2,6-bisphosphate by fructose 6-phosphate 2-kinase, and is formed from the degradation of fructose-2,6-bisphosphate by fructose-2,6-bisphosphate phosphatase. It is a product of the cytFBPase reaction, and inhibits degradation of fructose-2,6-bisphosphate, thus accumulation favours inhibition of cytFBPase.

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Pectin

Acidic polymers with high proportion of _D-galacturonic acid residues. Carboxylic acid groups have major effect on cell wall charge distribution and interactions with cations and anions in the extracellular phase. Functions in cell wall porosity, pH, ion balance, cell-cell adhesion, and recognition molecules. Includes homogalacturonan, rhamnogalacturonan I, and rhamnogalacturonan II. Has a negative charge that allows interactions with cations and the apoplastic water phase, affecting cell wall porosity. Around 200 β-1,4-galacturonic acid residues form linear chains that are arranged anti-parallel to each other. In the junction zone, chains are held together with Ca²⁺ ions interlaced in the network. Spacing of junction zone determines the pore size, and hence porosity of the cell wall. 

3,4,5-trihydroxybenzoic acid

A benzoic acid benzenoid.

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A sphingolipid. The head group is a complex oligosaccharide.

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A precursor of monoterpenoid indole alkaloid. An acyclic monoterpene which contributes a terpene component. It is converted into secoglanin in a series of nine enzymatic reactions. Smells sweet, and is found in roses and geraniums. 

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Geranyl diphosphate

A C10 trans-prenyl diphosphate. Synthesized by GPP synthase. Used to make monoterpenes and other isoprenoids. A scaffold for isoprenoids. Found in the plastid. Thought to be the "universal" substrate of monoterpene synthases.

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Geranylgeranyl pyrophosphate

A C20 trans-prenyl diphosphate. Synthesized by geranylgeranyl diphosphate synthase. A precursor for the isoprenoids tocopherol, chlorophyll, carotenoids, plastoquinone, gibberellin, and prenylated proteins. There are no biological functions for its cis isomers. It can be reduced to form phytyl diphosphate in the synthesis of tocopherol and other phytyl-containing plant metabolites.

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A phenolic found in ginger rhizome.

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Synthesized from ent-kaurene, a diterpene. A tetracyclic diterpenoid carboxylic acid. A plant hormone and growth regulator, involved in stem growth, fruit development, promotion of flowering, and breaking of dormancy. There are 135 in plants, fungi, and bacteria: GA₁ - GA₁₃₆. The most common active forms are GA₁, GA₃, and GA₄. Synthesis is more complex than other plant hormones. The conversion of ent-kaurene into GA involves membrane-associated P450s and soluble 2-oxoglutarate-dependent dioxygenases that are distributed between the plastid envelope, endoplasmic reticulum, and cytosol, respectively. Formation of GA₁₂ is the precursor for all other GAs.

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A glucosinolate found in cabbage.

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Not an end product of photosynthesis. Produced from degradation of starch in the chloroplast, and is exported to the cytosol via specific transpoters. Hydrolyzed from maltose in the cytosol. Phosphorylated by hexokinase in the cytosol. A common sugar linked to the backbone of flavonoids.

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Mustard oil

Sulphur- and nitrogen-containing plant secondary metabolites. Found largely in the order Brassicales, including brassica crops such as oilseed rape (Brassica napus), cabbage (B. oleracea), Arabidopsis thaliana, wasabi, and horseradish. Brassica vegetable dry mass contains about 200 μmol/g glucosinolates. Eating glucosinolates is associated with reduced incidence of cancer; has anti-cancer and anti-diabetes properties. The main contributors to bitterness in these vegetables; has a funny, sharp flavour. Unstable, and breaks down when cooking; steaming these vegetables retains glucosinolates better than boiling. Derived from amino acids, and grouped into aliphatic, aromatic, and indolic glucosinolates. There are approximately 120. Includes progoitrin, sinigrin, sinalbin, and glucobrassicin. All have glucose residue linked via a sulphur atom, and a variable R group, which is usually extensively modified from its amino acid precursor, and subject to a wide variety of transformations including hydroxylation, O-methylation, desaturation, glycosylation, and acylation. Synthesis phases include elongation, core structure assembly, and secondary modifications. Synthesis was delineated using radiolabelling with radioactive isotopes. Upon damage to the plant cell, glucosinolates are degraded to form hydrolysis products that are responsible for almost all biological activities, including isothiocyanate, oxazolinidine-2-thiones, nitriles, epithionitriles, and thiocyanates. Enzymes involved in degradation include myrosinase, and products produced are dictated by epithiospecifier proteins. It is a nitrogen sink. Can be toxic to pests, and may be bred into plants for this reason. Chopping up plants and putting it in the soil can reduce pests.

A major class of hemicellulose. Cross-links the walls of comelinoid monocots: palm, ginger, cypress, and grasses.

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An amino acid in the glutamate family. Used to form chlorophyll and glutathione. A moiety of folate. Formed in the mitochondria.

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Glutamine:2-oxoglutarate amino transferase

Converts glutamine and α-ketoglutarate into glutamate. Requires reductant: NADPH or ferredoxin.

A tripeptide formed enzymatically using amino acids glutamate, cysteine, and glycine. The peptide bond between glutamate and cysteine is not normal, designated as γ Glu. Synthesis has two ATP-requiring enzymes: γ-glutamyl-cysteine synthase and glutathione synthetase. S is transported in the phloem as glutathione. Has several functions including as an electron donor for sulphate reduction. Works in conjunctioin with ascorbate. A redox agent; shuttles between reduced and oxidized form.

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Synthesized from dihydroxyacetone phosphate (DAHP) by DAPH reductase. The precursor for glycerolipid synthesis. It is condensed with acyl carrier protein by G3P acyl transferase, forming lysophosphatidic acid (LPA).

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An amino acid in the 3-PGA family. Used to form glutathione, purines, cytokinin, and alkaloids.

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