2. Amino acids
•Amino acids are molecules that combine
to form protein
•The proteins on degradation (proteolysis)
release individual amino acids.
•There are 20 amino acid present in
human body. Valine is one of them
essential Amino acid
3. History and etymology
•Valine was first isolated from casein in 1901 by
Hermann Emil Fischer. The name valine comes from
valeric acid, which in turn is named after the plant
valerian due to the presence of the acid in the roots of
the plant
4. What is Valine ?
1.Valine (symbol Val or V) is an α-amino acid that
is used in the biosynthesis of proteins. It
contains an α-amino group (which is in the
protonated −NH3+ form under biological
conditions), an α-carboxylic acid group (which is
in the deprotonated −COO− form under
biological conditions), and a side chain isopropyl
group, making it a non-polar aliphatic amino
acid.
8. Function of valine:-
Valine is an essential amino acid, which means it cannot be synthesized
by the human body and must be obtained through the diet. Valine
plays several important roles in the body, including:
1)Protein synthesis: Valine is one of the building blocks of proteins,
which are essential for growth, repair, and maintenance of body
tissues.
2)Energy production: Valine is involved in the production of glucose,
which provides energy for the body’s cells.
9. 3)Muscle growth and repair: Valine is particularly
important for building and repairing muscle tissue. It
helps to maintain nitrogen balance in the body, which is
essential for muscle growth and repair.
4)Brain function: Valine is a precursor to
neurotransmitters such as dopamine and serotonin, which
are important for mood regulation, memory, and
cognitive function.
5)Immune function: Valine plays a role in the production
of white blood cells, which are essential for the body’s
immune system.
10. Metabolism
• Source and biosynthesis
• Enzymes involved in this biosynthesis include:
• Acetolactate synthase (also known as acetohydroxy
acid synthase)
• Acetohydroxy acid isomeroreductase
• Dihydroxyacid dehydratase
• Valine aminotransferase
11. Synthesis
• Racemic valine can be synthesized by bromination of
isovaleric acid followed by amination of the α-bromo
derivative:
HO2CCH2CH(CH3)2 + Br2 → HO2CCHBrCH(CH3)2 + HBr
HO2CCHBrCH(CH3)2 + 2 NH3 → HO2CCH(NH2)CH(CH3)2 +
NH4Br
12. Valine deficiency can cause many physical and mental
side effects such as low muscle tone (hypotonia),
hyperkinesia, hyperactivity, excessive drowsiness and
delayed mental and physical development. Low levels
of valine may also cause a deterioration in one’s mental
health, and insomnia.
13. Disorders related to valine
•There are several disorders related to valine
metabolism that can affect the body’s ability to
process or utilize valine properly. Some of these
disorders include:
14. • Maple syrup urine disease (MSUD): This is a rare genetic disorder that
affects the breakdown of branched-chain amino acids (BCAAs), including
valine. It leads to a buildup of these amino acids in the blood and urine,
causing serious health problems such as seizures, developmental delays,
and coma
• Propionic acidemia: Propionic acidemia is another rare genetic disorder
that affects the breakdown of branched-chain amino acids, including
valine. It is characterized by the buildup of toxic substances in the body
that can cause severe neurological problems, developmental delays, and
other health problems..
15. • Isovaleric acidemia: Isovaleric acidemia is a rare genetic disorder
that affects the metabolism of valine and other branched-chain
amino acids. It is characterized by the buildup of a toxic substance
called isovaleric acid, which can cause a range of symptoms,
including vomiting, seizures, and developmental delays.
• Ketotic hypoglycemia: Ketotic hypoglycemia is a condition in which
a person experiences low blood sugar levels due to an inability to
properly metabolize valine and other amino acids. It is most
commonly seen in infants and young children and can cause
symptoms such as lethargy, irritability, and seizures.
16. •Treatment for valine-related disorders generally
involves dietary management, including restricting the
intake of certain amino acids and supplementing with
others. In some cases, medication and other medical
interventions may also be necessary.
17. Dietary source of valine !
1. Meat: Beef, chicken, pork, and lamb are all good sources of valine.
2. Fish: Tuna, salmon, and other types of fish are also good sources of valine.
3. Dairy products: Milk, cheese, and yogurt are all rich in valine.
4. Legumes: Beans, lentils, and peas are good plant-based sources of valine.
5. Nuts and seeds: Almonds, peanuts, sesame seeds, and pumpkin seeds are all good sources of valine.
6. Whole grains: Quinoa, brown rice, and oats are all good sources of valine.
It’s important to note that the amount of valine in these foods can vary, so it’s important to eat a variety of
foods to meet your daily valine needs