Reactions and peptides are included except some indicated in the title slide

1. AMINO ACIDS
A short Presentation about Amino ACIDS
Important Peptides included except Peptide formation and Reactions of amino
acids
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2. Amino acids
- Are Carboxylic acids containing an amino group as a
general structure.
- Are white crystalline solids with relatively high
melting points and high water solubility
- Are ionic.
- Studies of Amino acids confirms that this true both in
solid state or in a solution.
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3. Amino acids
- The Presence of carboxyl group and a basic amino
group in the same molecule makes the transfer of a
hydrogen ion in a kind of internal acid- base
reaction possible.
- The product of this reaction is called a
“ZWITTERION” .
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4. AMINO acids
- Acts as acids and bases they are called
“Amphoteric substances” .
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5. ZWITTERION
- Dipolar Ion
- Has a net charge of 0 but positive charge in a acid
form.
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6. Naturally occurring amino acids
 Non-Polar, Aliphatic Amino Acids
 Aromatic Amino Acids
 Polar Uncharged Amino Acids
 Basic Amino Acids
 Acidic Amino Acids
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7. Non-polar, Aliphatic amino acid
 Include also all those with alkyl chain or aliphatic
R groups (e.g. Glycine, Alanine, valine, leucine and
Isoleucine alsoincluded, methionine [one of two sulfur
containing amino acids).
 Proline is not just a amino acid but also an alpha
amino acid
 Glycine is the simplest aliphatic amino acid
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8. Aromatic amino acid
 Phenylalanine, tyrosine and tryptophan, with
their aromatic side chains are non-polar
(hydrophobic)
 All can participate in a hydrophobic interactions.
 Tyrosine and tryptophan are more polar than
Phenylalanine
 Tryptophan and tyrosine absorb ultraviolet light
than Phenylalanine.
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9. Polar, uncharged amino acid
 R groups of these amino acids are more soluble in
water or more hydrophilic than those of the non-
polar amino acids because they contain functional
groups that form hydrogen bonds with water (H2O)
 Includes: Serine, threonine, cysteine, asparagine
and glutamine
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10. Basic amino acids
 The most hydrophilic R groups are those that are
either positively or negatively charged.
 Lysine (ph:7.0)- second primary amino at the end
position on its alipathic chain
 Arginine (positive charge; Guandino Group)
 Histidine has an imidazole group
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11. Acidic amino acid
 Aspartate and glutamate has a ph of 7, net
negative charge each has a second carboxyl group
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12. Physiological classification of amino
acid
 Essential amino acids- not synthesized in the body
but is needed or must be available or provided in
the diet for human and animal metabolic needs
 Non-Essential Amino Acid- can be synthesized in
adequate supply within the animal or human
 Semi- Essentials- can be synthesized but is lacking
of amount to need the body’s (human or animal)
need
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13. Essential Amino Acid
Isoleucine
Leucine
Lysine
Methionine
Phenylalanine
Threonine
Tryptophan
Valine
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14. Non-essential amino acid
Alanine
Asparagrine
Aspartic acid
Cysteine
Glutamic acid
Glutamine
Glycine
Proline
Serine
Tyrosine
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15. Semi-essential amino acid
Arginine
Histidine
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16. Unusual amino acid
 Ornithine, citrulline and arginino succinic acid of urea
cycle
 ß- alanine
 Taurine
 y- aminobutyric acid (a neurotransmitter)
 Mono and DI iodotyrosine
 Pantothenic acid
 Homoserine
 Homocysteine
 S- allycysteine suloxide
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17. Important peptides
- Vasopressine reduces urine formation
- Oxytocin causes the smooth muscle of the uterus to
contract often administered to induce labor
- Adrenocorticotropic hormone (ACTH) regulates
the production of steroid hormones in the cortex
and adrenal gland
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18. Important peptides
- Glutathione consist of glutamate, cysteine and
glycine acts as reducing agent in all cells
- Angiotensin II found in lungs and other cells
powerful vasoconstrictor and raises blood pressure
- Bradykinin (nine amino acid residues) powerul
vasodilator and anti inflammatory agent
- Enkaphalin consist of tyrosine, glycine,
phenylalanine and methionine serves as our body’s
analgesic.
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19. Color tests to identify amino acids
1) Ninhydrin test- general test for proteins.
Identifies if amino acids are present in a sample.
Blue- violet positive result.
2) Biuret’s test- used to test the presence of peptide
bonds in a sample. Violet solution positive result
3) Xanthoproteic test- used to test the presence of
aromatic amino acid. Formation of yellowish
mixture or solution is the positive result.
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20. Color test to identify amino acids
4) millon’s test- test for the presence of a polar
Hydroxyl group (OH) in a amino acid. Crimson red
mixture or solution positive result.
5) hopkin’s cole test- test for the presence of indole
ring in amino acids. Violet ring in a mixture or in
solution. (proline and histidine must yield a
positive result).
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21. ABBREVIATIONS
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22. AMINO ACID Abbreviations
Glycine Gly
Alanine Ala
Valine Val
Leucine Leu
Isoleucine Ile
Methamine Met
Cysteine Cys
Phenylalalnine Phe
Tyrosine Tyr
Tyrptophan Trp
Aspartate Asp
Glutamate Glu
Histidine His
Lysine lys
Arginine Arg
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23. Phenylketonuria
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 Rare condition in which the body cannot
properly use one of the building blocks of
protein called “Phenylalanine” that with
excessive accumulation can lead to brain
damage and whole lot variety of health
problems.

24. Maple Syrup urine disease
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 Inherited disorder where the body cannot
process certain protein building blocks (amino
acids) properly
 The distinctive sweet odor of affected infants
urine and is also characterized by poor
feeding, vomiting, lack of energy (lethargy) and
a delay on development.
 If left untreated can lead to seizures, comatose
and then death.
 Urine is Black and smells maple syrup