Secondary metabolites

Metabolites

Metabolites are all the products of metabolism

A primary metabolite is directly involved in normal growth, development, and reproduction.

A secondary metabolite is not directly involved in those processes, but usually has an important ecological function.

• Specific organs • Specific tissues • Specific cell type • Specific stages of development

Commonly secondary metabolites are produced in one part of the plant and stored in other part

Constitutive defenses always present in the plant species

Induced defenses synthesized or mobilized to the site where a plant is injured

Metabolites

Alkaloids

Alkaline nitrogenous compounds

Analgesics are selective central nervous system depressants used to relieve pain.

Heroin: esterification reaction

Papaver somniferum Alkaloids

Papaver somniferum Alkaloids

1)  Morphine  and  codeine  -­‐  natural  alkaloids  of  opium.  

2)  Synthe;c  deriva;ves  of  morphine  such  as  heroin.  

3)  Synthe;c  agents  which  resemble  the  morphine  structure.  

4)  Narco;c  antagonists  which  are  used  as  an;dotes  for  overdoses  of  narco;c  analgesics.  

The seeds from this poppy are protected by and inner skin from the alkaloids.

•  vitamins •  minerals •  omega fatty acids like •  linolic acid

Other products from Papaver somniferum

Pure poppy seed oil Modify poppy seed oil used for making soaps, creams and other products.

Papaver somniferum Alkaloids

Erythroxylum coca Alkaloids

There are around 250 species of Erythroxylon.

Erythroxylon coca E. novogranatense

The first and most abundant harvest is in March after the rainy season, the second is at the end of June, and the third in October or November

Pain killer Constriction of the blood vessels

Erythroxylum coca Alkaloids

Charged molecules don't cross cell membranes

Erythroxylum coca Alkaloids

Caffeine Caffeine is a psychoactive stimulant drug Natural pesticide Allelopathic compound

Yerba mate Guarana berries Yaupon Holly Coffe Tea Cocao

Ilex vomitoria

Theobroma cacao

Nicotine Biosynthesis takes place in the roots, and accumulating in the leaves

Nicotine is a stimulant, it raises blood pressure, and is a vasoconstrictor

Long-term resistance, or systemic acquired resistance (SAR)

Gaseous hormones

• jasmonic acid • salicylic acid

Warning!!! the plant is no longer edible

"an enemy of my enemy is my friend,”

Phytoalexin Nicotine

phytoalexin produced during the tobacco defense response, (right hand image shows leaf viewed under UV light).

Terpenoids They can be classified by the number of isoprene units that they have (C5H8)

volatile essential oils such as citronella, limonene, menthol, camphor, and pinene.

Terpenoids

Terpenoids are toxic for some organisms

Silica and lignins, which are completely indigestible to animals, grind down insect mandibles.

Phenolics

Antiseptic properties. Antioxidant properties.

Disrupt endocrine activity. Interfering with protein absorption and digestive enzymes.

The synthesis of fluoroacetate in several plants is an example for the use of small molecules to disturb the metabolism of the herbivore, in this case the citric acid cycle.

Flavonoids:

red, blue, yellow, and white pigments.

lignin, silymarin and cannabinoids.

Phenolics

Lignin is deposited in the cell wall by a lignification process The structure of plants is the consequence of lignification Water proofs the cell wall

Phenolics

2nd  

The Cell and the cell cycle

Cells are the structural and functional units of all known living organisms

Prokaryotes Eukaryotes

DNA

The cell cycle

Photosynthetic eukaryote

Chloroplast

Chloroplast photorelocation in a protonemal cell of the fern Adiantum capillus-veneris

Cytoskeleton and cytoplasmic streaming

Mitosis

Early prophase

Late prophase Metaphase Anaphase Telophase

Cytokinesis

The phragmoplast is a complex assembly of microtubules, microfilaments, and endoplasmic reticulum

The phragmosome is a sheet of cytoplasm forming in highly vacuolated plant cells in preparation for mitosis.

Attendance 1. What are the differences between primary metabolites and secondary metabolites?

2.In a plant, what is an induced defense?

3.What is the R- group for alkaloids?

4.Why is it possible to eat seeds of Papaver somniferum without becoming intoxicated?

5.What is the function of phytoalexins ?

6.What parts of the plant cell cycle are not found in the animal cell cycle?