Wednesday, July 29, 2009
Amino acids are the building blocks of proteins. Our bodies break down the proteins we eat into amino acids, which in turn is used to create ate proteins that need to operate. Proteins serve many di erent functions: Structural, transport, catalysis, contraction, and protection against disease.
Amino acids are also involved in many non-protein reactions. Aminoacids
are used to produce neurotransmitters, hormones and other metabolites
such as creatine or citrulline. Amino acids can also be used as a source of
There are 20 amino acids that make up the majority of mammalian proteins. Each of the amino acids
acid has a similar structure, but di er in the type of side chain attached to
each α-carbon. The side chains confer di erent properties of each amino acid
acid, and are responsible for the three "native" structure
Amino acids are essential ed classification, non-essential, or conditions --
• Essential amino acids are those that our body can not and should
be supplied by the foods we eat. There are 8 essential amino acids: I --
thionine, leucine, valine, isoleucine, threonine, tryptophan, lysine, and
phenylalanine. You can see the number listed as 9 or 10 in some colo --
is, as arginine and histidine are essential amino acids for infants and
very young children.
• non-essential amino acids can be produced by the body of other
• conditionally essential amino acids are essential amino acids that
become essential under conditions of physical stress or trauma, when
the body can not produce a sufficient quantity to meet demand. Some
conditionally essential amino acids are glutamine, arginine, cysteine
Not all amino acids found in proteins. For example, taurine and
beta-alanine functions not only of protein.