Glutamate is an amino acid that plays important roles in plant growth and development. It can be synthesized via two main pathways: the glutamate synthase pathway using glutamine and α-ketoglutarate, and the glutamate dehydrogenase pathway using α-ketoglutarate. Glutamate is involved in biosynthesis of many other amino acids and acts as a signaling molecule under normal and stress conditions in plants. The key enzymes involved in glutamate synthesis and metabolism are glutamate synthase and glutamate dehydrogenase. Modern techniques like HPLC and NMR are used to identify and quantify amino acids like glutamate in plant tissues.

1. Done By÷
Abhilash Poudyal
Kaushal Pradhan
Barsha Subba
Anushilta Pradhan
Sanju Neopanay
Grace Pradhan

2. AMINOACIDS
 The first few amino acids were discovered in the early 19th century.
 In 1806, French chemists Louis-Nicolas Vauquelin and Pierre Jean Robiquet
isolated a compound in asparagus that was subsequently named asparagine, the
first amino acid to be discovered.
 Amino acid,is a group of organic molecules that consist of a basic amino group
(―NH2), an acidic carboxyl group (―COOH), and an organic R group (or side chain)
that is unique to each amino acid.
 Amino acids and proteins that are the building blocks of life. When proteins are
digested or broken down, amino acids are left. The human body uses amino acids to
make proteins to help the body food break down.
 They are involved in almost every body function, including growth and
development, healing and repair, normal digestion, and providing energy for our
body.

3. TYPES OF AMINO ACID÷
Amino acids are classified into three groups:Essential amino
acids ,Nonessential amino acids and Conditional amino
acids.
Essential Amino acids÷Essential amino acids cannot be made by the body. As a
result, they must come from food.The 9 essential amino acids are: histidine,
isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and
valine.
Non-essential Amino acids ÷Nonessential means that our bodies produce an amino
acid, even if we do not get it from the food we eat. Nonessential amino acids include:
alanine, arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine,
glycine, proline, serine, and tyrosine.
Conditional Amino acids÷Conditional amino acids are usually not essential, except in
times of illness and stress.Conditional amino acids include: arginine, cysteine,

4. GLUTAMATE ÷
 It is well known that glutamate (Glu), a neurotransmitter in human body, is
a protein amino acid.
 It plays a very important role in plant growth and development.
 Nowadays , glutamate has been found to emerge as signaling role.
 Under normal conditions, glutamate takes part in seed germination, root
architecture, pollen germination, and pollen tube growth.
 Under stress condition, glutamate participates in wound response, pathogen
resistance, response and adaptation to abiotic stress.
- such as: salt, cold, heat and drought
 And local stimulation (abiotic or biotic stress)- triggered long distance
signaling transduction.

5. STRUCTURE
Molecular formula- C5H8NO4
IUPAC name- 2-Aminopentanedioic acid
Molar mass- 147.13g/mol

6. GLUTAMATE SYNTHESIS÷

7. STEPS Glutamate is derived from the intermediate of glycolysis And citric acid cycle/krebs cycle.
 In plants, glutamate can be principally synthesized via glutamate synthetase (GS)/
glutamate synthase also known as glutamate-alpha-ketoglutarate amino transferase
(GOGAT) cycle in the chloroplasts of photosynthetic tissue or non-photosynthetic tissue
plastids and glutamate dehydrogenase (GDH) in mitochondria or cytoplasm.
 Alpha-ketoglutarate is an intermediate of krebs cycle which is involved in the process of
biosynthesis of many amino acid involving glutamate,glutamine.
 In krebs cycle acetylcoa is converted into citrate via the enzyme citrate synthase.
 And again conversion of citrate into isocitrate is done by the enzyme aconitase.
 Isocitrate is then converted into alpha ketoglutarate via the enzyme isocitrate
dehydrogenase
 Glutamate dehydrogenase converts α-ketoglutarate to glutamate and is dependent on
NAD+/NADH or NADP+/NADPH.
 The glutamate branched and synthesizes the glutamine through glutamine synthetase.
 Glutamate is the precursor of other various amino acid involving arginine (through the
amino acid orithine) and Prolin.

8. METABOLISMS

9. GLUTAMATE
METABOLISMS
 glutamate is a central molecule in amino acid metabolism in higher plants. The
α-amino group of glutamate is directly involved in both the assimilation and
dissimilation of ammonia and is transferred to all other amino acids.
 In addition, both the carbon skeleton and α-amino group form the basis for the
synthesis of γ-aminobutyric acid (GABA), arginine, and proline. It should also be
noted that glutamate is the precursor for chlorophyll synthesis in developing
leaves).
 Finally, glutamate may be deaminated by glutamate dehydrogenase to form
ammonia and 2-oxoglutarate.

10. ENZYME INVOLVED
Glutamine synthetase–glutamate synthase
 The key enzyme involved in the de novo synthesis of glutamate is
glutamate synthase, also known as glutamine:2-oxoglutarate
aminotransferase (GOGAT).
 The reaction is a reductant-driven transfer of the amide amino group of
glutamine to 2-oxoglutarate to yield two molecules of glutamate.
 The enzyme in plants is present in two distinct forms, one that uses
reduced ferredoxin as the electron donor and one that uses NADH as the
electron donor.

11. Glutamate dehydrogenase ÷
 Two enzymes involved in glutamate synthesis discussed previously
catalyse irreversible reactions.
 A third enzyme, glutamate dehydrogenase catalyse a reversible
amination/deamination reaction, which could lead to either the synthesis
or the catabolism of glutamate.
 During the last 33 years, the role of GDH in glutamate metabolism in
plants has been the subject of continued controversy .
 However, following recent investigations into the regulation of the genes
encoding the enzyme protein, the presence of overexpressing and antisense
lines and the use of nuclear magnetic resonance (NMR) and gas
chromatography–mass spectrometry (GC-MS) techniques, the role is
becoming clear.

12. IDENTIFYING AND
QUANTIFYING
1 .Methods for identifying and quantifying amino acids have
improved dramatically over the last 50 years, from paper
chromatography to ion exchange chromatography
2.HPLC
3.NMR
It should be remembered that the plant extracts used will have
been derived from a range of intracellular organelles as well as
extracellular material although the differences in amino acid
concentrations between these organelles may not be very large

13.  Pharmacognosy and phytochemistry by Nirali Prakashan.
 https://medlineplus.gov/ency/article/002222.htm
 https://pubmed.ncbi.nlm.nih.gov/17578865/#:~:text=Glutamate%20o
ccupies%20a%20central%20position,utilizing%20glutamine%20and
%202%2Doxoglutarate.&text=Evidence%20that%20the%20well%2D
known,the%20plant%20kingdom%20is%20reviewed
 https://www.sciencedirect.com/topics/nursing-and-health-
professions/glutamate-
dehydrogenase#:~:text=Glutamate%20dehydrogenase%20incorporat
es%20free%20ammonium,and%20OAA%20to%20make%20aspartate

15. THANK YOU