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Valine (abbreviated as Val or V) is an a-amino acid
Amino acid

In chemistry, an amino acid is a molecule containing both amine and carboxyl functional groups. These molecules are particularly important in biochemistry, where this term refers to alpha-amino acids with the general formula H2NCHRCOOH, where R is an organic substituent....
 with the chemical formula
Chemical formula

A chemical formula is a way of expressing information about the atoms that constitute a particular chemical compound, and how the relationship between those atoms changes in chemical reactions....
 HO2CCH(NH2)CH(CH3)2. L-Valine is one of 20 proteogenic amino acids. Its codons are GUU, GUC, GUA, and GUG. This essential amino acid
Essential amino acid

File:BakedFish.jpgAn essential amino acid or indispensable amino acid is an amino acid that cannot be synthesized de novo synthesis by the organism , and therefore must be supplied in the diet....
 is classified as nonpolar. Along with leucine
Leucine

Leucine is an a-amino acid with the chemical formula HO2CCHCH2CH2. It is an essential amino acid, which means that humans cannot synthesise it....
 and isoleucine
Isoleucine

Isoleucine is an a-amino acid with the chemical formula HO2CCHCHCH2CH3. It is an essential amino acid, which means that humans cannot synthesize it, so it must be part of our diet....
, valine is a branched-chain amino acid
Branched-chain amino acids

The phrase branched-chain amino acids or BCAA is sometimes used to refer to the amino acids having aliphatic side-chains that are non-linear....
. It is named after the plant valerian. In sickle-cell disease
Sickle-cell disease

Sickle-cell disease or sickle-cell anaemia is a life-long blood disorder characterized by red blood cells that assume an abnormal, rigid, sickle shape....
, valine substitutes for the hydrophilic amino acid
Amino acid

In chemistry, an amino acid is a molecule containing both amine and carboxyl functional groups. These molecules are particularly important in biochemistry, where this term refers to alpha-amino acids with the general formula H2NCHRCOOH, where R is an organic substituent....
 glutamic acid
Glutamic acid

Glutamic acid is one of the 20 proteinogenic amino acids and its codons are GAA and GAG. It is a non-essential amino acid. The carboxylate anions and salt of glutamic acid are known as glutamates....
 in hemoglobin
Hemoglobin

Hemoglobin is the iron-containing oxygen-transport metalloprotein in the red blood cells of vertebrates, and the tissues of some invertebrates....
.






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Valine (abbreviated as Val or V) is an a-amino acid
Amino acid

In chemistry, an amino acid is a molecule containing both amine and carboxyl functional groups. These molecules are particularly important in biochemistry, where this term refers to alpha-amino acids with the general formula H2NCHRCOOH, where R is an organic substituent....
 with the chemical formula
Chemical formula

A chemical formula is a way of expressing information about the atoms that constitute a particular chemical compound, and how the relationship between those atoms changes in chemical reactions....
 HO2CCH(NH2)CH(CH3)2. L-Valine is one of 20 proteogenic amino acids. Its codons are GUU, GUC, GUA, and GUG. This essential amino acid
Essential amino acid

File:BakedFish.jpgAn essential amino acid or indispensable amino acid is an amino acid that cannot be synthesized de novo synthesis by the organism , and therefore must be supplied in the diet....
 is classified as nonpolar. Along with leucine
Leucine

Leucine is an a-amino acid with the chemical formula HO2CCHCH2CH2. It is an essential amino acid, which means that humans cannot synthesise it....
 and isoleucine
Isoleucine

Isoleucine is an a-amino acid with the chemical formula HO2CCHCHCH2CH3. It is an essential amino acid, which means that humans cannot synthesize it, so it must be part of our diet....
, valine is a branched-chain amino acid
Branched-chain amino acids

The phrase branched-chain amino acids or BCAA is sometimes used to refer to the amino acids having aliphatic side-chains that are non-linear....
. It is named after the plant valerian. In sickle-cell disease
Sickle-cell disease

Sickle-cell disease or sickle-cell anaemia is a life-long blood disorder characterized by red blood cells that assume an abnormal, rigid, sickle shape....
, valine substitutes for the hydrophilic amino acid
Amino acid

In chemistry, an amino acid is a molecule containing both amine and carboxyl functional groups. These molecules are particularly important in biochemistry, where this term refers to alpha-amino acids with the general formula H2NCHRCOOH, where R is an organic substituent....
 glutamic acid
Glutamic acid

Glutamic acid is one of the 20 proteinogenic amino acids and its codons are GAA and GAG. It is a non-essential amino acid. The carboxylate anions and salt of glutamic acid are known as glutamates....
 in hemoglobin
Hemoglobin

Hemoglobin is the iron-containing oxygen-transport metalloprotein in the red blood cells of vertebrates, and the tissues of some invertebrates....
. Because valine is hydrophobic, the hemoglobin does not fold
Protein folding

Protein folding is the physical process by which a polypeptide folds into its characteristic and functional protein structure.Each protein begins as a polypeptide, translated from a sequence of mRNA as a linear chain of amino acids....
 correctly.

Biosynthesis

Valine is an essential amino acid, hence it must be ingested, usually as a component of proteins. It is synthesized in plants via several steps starting from pyruvic acid
Pyruvic acid

Pyruvic acid is an organic acid. It is also a ketone. It is the simplest keto acids. The carboxylate ion of pyruvic acid is known as pyruvate....
. The initial part of the pathway also leads to leucine
Leucine

Leucine is an a-amino acid with the chemical formula HO2CCHCH2CH2. It is an essential amino acid, which means that humans cannot synthesise it....
. The intermediate a-ketovalerate undergoes reductive amination with glutamate. Enzymes involved in this biosynthesis include:
  1. Acetolactate synthase
    Acetolactate synthase

    The acetolactate synthase enzyme is a protein which in humans is encoded by the ILVBL gene. ALS catalyzes the first step in the synthesis of the branched-chain amino acids ....
     (also known as acetohydroxy acid synthase)
  2. Acetohydroxy acid isomeroreductase
  3. Dihydroxyacid dehydratase
  4. Valine aminotransferase


Synthesis

Racemic valine can be synthesized by bromination of isovaleric acid
3-Methylbutanoic acid

3-Methylbutanoic acid, or more commonly isovaleric acid, is a natural fatty acid found in a wide variety of plants and essential oils. Isovaleric acid is clear colorless liquid that is sparingly soluble in water, but extremely soluble in most common organic solvents....
 followed by amination of the a-bromo derivative
HO2CCH2CH(CH3)2 + Br2
Bromine

Bromine , , meaning "stench " ), is a chemical element with the symbol Br and atomic number 35. A halogen element, bromine is a reddish-brown Volatility liquid at Standard conditions for temperature and pressure that is intermediate in reactivity between chlorine and iodine....
  ? HO2CCHBrCH(CH3)2 + HBr
Hydrogen bromide

Hydrogen bromide is the diatomic molecule HydrogenBromine. Under standard conditions, HBr is a gas, but it can be liquified. The aqueous solution hydrobromic acid forms upon dissolving HBr in water....
HO2CCHBrCH(CH3)2 + 2 NH3 ? HO2CCH(NH2)CH(CH3)2 + NH4Br


Dietary aspects

Nutrition
Nutrition

Nutrition is the provision, to cells and organisms, of the materials necessary to support life. Many common health problems can be prevented or alleviated with good nutrition....
al sources of valine include cottage cheese, fish, poultry, peanuts, sesame seeds, and lentils.

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