An introduction to amino acids

[cleaver]

Just a compilation of information I've collated over the last few months.

AMINO ACIDS are found in all foods except oil. Despite claims to the contrary, all vegetables, legumes, and grains contain all the essential amino acids. They may not contain high amounts of some, but, if combined with another vegetable source, all the essential amino acid requirements are met.

There are about eighty amino acids found in nature, but only twenty to twenty-nine are required for human growth. This figure depends upon the source consulted but most agree the figure is twenty or twenty-one. Once again, depending on the source, eight to ten amino acids are considered essential for life. The reason for the classifications of amino acids into "essential" and "non-essential" was to distinguish between those the body could manufacture and the ones that had to come from diet.

Essential amino acids are those that must come from the diet. These include: isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.

Non-essential amino acids are those that the body can manufacture from an available source of nitrogen and a carbon skeleton. These include: alanine, asparagine, aspartic acid, carnitine, citrulline, cysteine, cystine, GABA, glutamic acid, glutamine, gluthathione, glycine, hydroxyproline, ornithine, proline, serine, taurine, and tyrosine.

Semi-essential amino acids are ones that can sometimes be made internally if conditions are right. Arginine and histidine can be converted from other amino acids if needed. Methionine can be converted to cystine, but cystine cannot be converted to methionine. Phenylalanine can be converted to tyrosine, but not the other way around. Therefore, when cystine and tyrosine are present in the diet, the requirements for methionine and phenylalaine are reduced. Thus, cystine and tyrosine are sometimes classified as "semi-essential." The liver is able to produce 80% of the amino acids it needs for protein construction, while the remaining 20% must be consumed.

Proteins are classified according to:
1) composition and chemical properties, ie., simple, conjugated, compound, or derived
2) nutritional quality, ie., complete, partially complete, or incomplete
3) structure, ie., fibrous or globular
4) solubility in water, acid, or alcohol.

Based on their content of amino acids, foods are often classified as complete, partially complete, or incomplete protein sources. In order for a protein to be complete, it must contain all of the essential amino acids. This is the reason that many nutritionists rank non-meat foods as being incomplete. The foods do contain all amino acids, but some may be in lower proportions than are required, and, therefore, should be combined with another food containing higher amounts of these amino acids.

Amino acid construction consists of carbon, hydrogen, oxygen, and nitrogen with some containing sulfur. Every amino acid, with the exception of glycine, comes in two forms -- a left-handed (L) version and a right-handed (D) version, which are identical mirror images of each other. However, protein chains cannot be formed from a mixture of D and L amino acids. An L series is found naturally in plant and animal sources. Over-the-counter supplements in an L series are more preferable since they are more compatible to the human makeup.

The body uses, almost without exception, from the L forms, but some D forms have been used therapeutically. The one exception is with phenylalanine, which can appear as both an L and a DL configuration. The DL supplements are generally chemically manufactured and are not as easily assimilated as the L configuration.

In order for the protein-building process to occur in the body, there must be enough quality protein in the diet; and that protein must be easily digestible in order for the breakdown (catabolism) and rebuilding (anabolism) of vital nutrients to occur. The body continually breaks down protein molecules and rebuilds the resulting amino acids into other usable chains required by particular areas of the body. Amino acids compete with each other for entry to the brain. Therefore, to avoid this competition, amino acid supplements should be taken on an empty stomach.

In addition to their main functions of building needed proteins, amino acids also assist vitamins and minerals to do their jobs properly. Even if vitamins and minerals were absorbed and assimilated rapidly, they would not be as effective as they are in the presence of amino acids. In order to be properly assimilated, amino acids particularly require the help of Vitamins B12, Bw, C, and T, chromium, and sleep.

Vegans must be aware that most of the amino acid supplements available have an animal-base. There are supplements -- derived from vegetable sources -- in a crystalline free form that are more stable and preferable because of their rapid absorption. However, labels must be read carefully.

Also, beware of alkali-treated soy products. This treatment tends to reduce three amino acids -- lysine, serine, and cystine -- as well as produce a toxic amino acid derivative called lysinoalanine. In addition, more people are showing allergy symptoms toward soy products, which may or may not be as a result of products using genetically engineered soybeans.

Amino acids are actively transported, but also require a carrier; and each carrier is specific to certain amino acids. For example:

Carrier 1 is for serine, threonine, and alanine.
Carrier 2 is for phenylalanine, tyrosine, methionine, valine, leucine, and isoleucine.
Carrier 3 is for proline and hydroxyproline.
Carrier 4 is for taurine and B-alanine.
Carrier 5 is for lysine, arginine, cysteine.
Carrier 6 is for aspartic acid and glutamic acid.

Chemical Division for Amino Acids:

1. Aromatic Amino Acids: Phenylalanine, Tyrosine, Tryptophan
2. Sulfur Amino Acids: Cysteine, Gluthathione, Taurine, Methionine, Homocysteine
3. Urea Cycle Amino Acids: Arginine, Citrulline, Ornithine
4. Glutamate Amino Acids: Glutamic Acid, GABA and Glutamine; Proline and Hydroxyproline; Aspartic Acid-Asparagine
5. Threonine Amino Acids: Threonine; Glycine; Serine; Alanine
6. Branched Chain Amino Acids (BCAA): Leucine, Isoleucine, and Valine
7. Important Metabolite Amino Acids: Lysine; Carnitine; Histidine

Diseases directly related to amino acid metabolism difficulties (Thorsons):

Alanine: (Lactic acidosis)
Arginine: (Hyperargininaemia)
Argininosuccinic acid: (Arginosuccinicaduria)
b-Alanine: (Beta-alaninaemia)
Citrulline: (Citrullinaemia)
Cystine: (Cystinosis and Cystinuria)
Glutamic acid: (Pyroglutamic acidaemia)
Glycine: (Nonketotic hyperglycinaemia and Ketotic hyperglycinaemia)
Histidine: (Histidinaemia)
Homocystine: (Homocystineuria)
Isoleucine: (Propionic acidaemia and MSUD - Maple Syrup Urine Disease)
Leucine: (Isovaleric acidaemia and MSUD)
Lysine: (Hyperlysinaemia)
Methionine: (Hypermethioninaemia)
Ornithine: (Hyperornithinaemia and Ornithine aminotransferase deficiency)
Phenylalanine: (Phenylketonuria - PKU and Atypical PKU)
Pipecolic acid: (Hyperpipecolicaemia and Zellwagers' syndrome)
Proline: (Hyperprolineaemia I and II)
Serine: (Hyperoxaluri II)
Threonine: (Hyperthreoninaemia)
Tryptophan: (Tryptophanuria)
Tyrosine: (Hereditary tyrosinaemia)
Valine : (Hypervalinaemia)

[cleaver]

If you are taking a single amino acid as a supplement, taking it with empty stomach may help its absorption.
If you are taking amino acid supplements, L-Forms are recommended as they are more acceptable to the body.
Keep in mind, the amino acid basics; amino acids work best when all of essential and non-essential ones are provided to the body.
Vitamin B6 and Vitamin C are the vitamins needed for amino acid metabolism and to help with the absorption of amino acids. Include these vitamins with your amino acid supplements

Gelatin is the only animal protein that is not considered a complete protein.

Health benefits of amino acids

Amino acids are needed to build the various proteins used in the growth, repair, and maintenance of body tissues. Amino acids play innumerable roles in human health and disease.

Alanine is necessary for the promotion of proper blood glucose levels from dietary protein. It stimulates lymphocyte production and may help people who have immune suppression. It also strengthens the immune system by producing antibodies.

Asparagine is needed to maintain a balance, preventing over nervousness or being overly calm.

Carnosine is the water-soluble counterpart to vitamin E in protecting cell membranes from oxidative damage.

Citrulline supports the body in optimizing blood flow through its conversion to l-arginine and then nitric oxide.

Creatine supplements fuels and enhances short bursts of high-energy exercise. Creatine prevents the body from relying solely on the process of glycolysis.

Cysteine strengthens the protective lining of the stomach and intestines, which may help prevent damage caused by aspirin and similar drugs.

GABA has been used in the treatment of depression, manic-depressive (bipolar) disorder, seizures, premenstrual dysphoric (feeling depressed) disorder, and anxiety.

Glutamine regulates immune system, nitrogen shuttling, oxidative stress, muscle preservation, intestinal health, injuries, and much more.

Glutathione are necessary for supporting the immune system, glutathione is required for replication of the lymphocyte immune cells.

Glycine is an inhibitory amino acid with important functions centrally and peripherally.

Histidine is known to be vital in the maintenance of the myelin sheaths surrounding nerves, particularly the auditory nerve and is used to treat some forms of hearing disability.

Isoleucine is necessary for the optimal growth of infants and for nitrogen balance in adults.

L-arginine is used by the immune system to help regulate the activity of the thymus gland, which is responsible for manufacturing T lymphocytes.

L-carnosine supports healthy aging and cellular rejuvenation by its effects on two mechanisms: glycosylation and free radical damage.

Leucine is used as a source for the synthesis of blood sugar in the liver during starvation, stress, and infection to aid in healing.

L-theanine reduces stress and anxiety without the tranquilizing effects found in many other calming supplements.

Lysine is used in managing and preventing painful and unsightly herpes sores caused by the herpes simplex virus.

Methionine helps remove fat from the liver.

Phenylalanine is used to treated depression, rheumatoid arthritis and osteoarthritis, menstrual cramps, Parkinson's disease, vitiligo, and cancer.

Proline is an important component in certain medical wound dressings that use collagen fragments to stimulate wound healing.

Serine is needed for the metabolism of fats and fatty acids, muscle growth, and a healthy immune system.

Taurine helps regulate the contraction and pumping action of the heart muscle and it helps regulate blood pressure and platelet aggregation.

Threonine may enhance immunity by assisting in the production of agents that fight viral infections.

Tryptophan is important for the production of serotonin. Increasing tryptophan may help to normalize sleep patterns.

Tyrosine may act as an adaptogen, helping the body adapt to and cope with the effects of physical or psychological stress by minimizing the symptoms brought on by stress.

Valine is useful in treatments involving muscle, mental, and emotional upsets, and for insomnia and nervousness.

[Orinoco]

Excellent post. A lot of new info to digest there.

This post would make a good 'sticky'.

[Dtlv74]

Damn it, it won't let me rep you again until I've loved some more people - great compliation of stuff.

Funnily enough I've been collecting some info on amino acids myself recently, but had not yet found some of the info towards the end of your post.

One thing not on there which I'd like to find is some data as to whether/how severly aminos which use the same carrier compete with each other for absorption. This is probably not going to be a big issue in nutrition or supplementation, unless there is something abnormal going on, but would like to know none the less just out of curiosity.

Anyway good stuff Cleaver - that must have taken a while

[cheef]

really good info mate
repped

[Bison]

Quote

Excellent post. A lot of new info to digest there.

This post would make a good 'sticky'.

Agreed on both counts. Stickied

[mxd]

****ing awesome! RePpEd

"Carrier 4 is for taurine and B-alanine."

~and thank you cleaver for clarifying why taurine and beta alanine compete for absorption, hope you all listen now!

[Dtlv74]

This is a bit cheeky... though it might be useful to add one of my earlier posts about amino solubility to this excellent thread. Keeps all the info together for easy reference

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Amino Acid Solubility

Something I've wondered about for a while is exactly how soluble the amino's I guzzle everyday are, and whether I've been ingesting them in suspension rather than in solution - and if this affects their bioavailability.

Having done a bit of searching around, I've managed to compile the following list of amino acids commonly taken as/used in supplements, along with some info on their solubilty, in g/100ml of water at 25 degrees C.

Fortunately, it seems even those which are least soluble still don't require too much water for all but a very high dose. Leucine seems to be the only one which some people might not be dissolving properly, requiring 100ml of water for every 2.4g taken.

Amino Acid Solubility

* Alanine 16.65g/100ml
* Arginine 15g/100ml
* Cysteine - very soluble
* Glutamic Acid 0.864g/100ml
* Glutamine 2.5g/100ml
* Glycine 24.99g/100ml
* Histidine 4.19g/100ml
* Isoleucine 4.117g/100ml
* Leucine 2.426g/100ml
* Lysine - very soluble
* Methionine 3.381g/100ml
* Phenylalanine 2.965g/100ml
* Proline 162.3g/100ml
* Serine 5.023g/100ml
* Taurine 10.48g/100ml
* Threonine - very soluble
* Tryptophan 1.136g/100ml
* Tyrosine 0.0453g/100ml
* Valine 8.85g/100ml

* Creatine Monohydrate 1g/100ml

Have also had a look at MP's essential aminos and BCAA's, and worked out an approximate minimum quantity of water (fraction rounded) for those based upon the least soluble amino in each - Leucine in both cases (hope I've got my maths right!).

* MP's EAA powder 7.5g/100ml (approximate worked out by least soluble amino)
* MP's BCAA powder 4.9g/100ml (approximate worked out by least soluble amino)

Note; while those figures are low, using only those quantities of fluids would create saturated solutions which would probably require a lot of shaking/stirring, and they would probably taste pretty damn vile. Much more fluid would be recommended!

One question I haven't been able to find a conclusive answer on is whether or not it is actually necessary to dissolve them at all. Does anyone know? I've been working under the assumption that it is necessary, both to avoid digestive discomfort and to ensure maximum utilization... is this correct?

[Dtlv74]

Found this, thought I'd copy up and post. Is short on specifics but might form a useful base for further research.

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Major Areas of Therapeutic Application of Amino Acid Therapy

Detoxification of heavy metals:
Methionine, cysteine, cystine and glutathione (Sulphur containing amino acids).
Histidine.

Counteracting effects of free radical activity:
Methionine.
Glutathione.

Assistance in fat metabolism:
Methionine.
Taurine.
Carnitine.

Acceleration of wound healing:
Arginine.
Proline/hydroxyproline (collagen-connective tissue regeneration).

Control of viral infection:
Lysine.

Thymus activity enhancement:
Arginine.

Glucose tolerance improvement/enhanced insulin production-utilization:
Arginine.
Taurine.
Glutamic acid.
Cysteine.
Glycine.

Immune system enhancement:
Glutathione.

Rheumatoid Arthritis:
Histidine.

Brain detoxifier (of ammonia):
Glutamic acid.

Brain detoxifier (of histamine in histadelic schizophrenia):
Methionine.

Protection against radiation effects:
Histidine.
Glutathione.
Cystine.

Weight control – Obesity:
Phenylalanine, tryptophan (Appetite Control and better food selection).
Valine.
Methionine.
Carnitine (mobilizing fat deposits).

Depression:
Phenylalanine.
Tryptophan.
Tyrosine.
Glutamine/Glutamic acid.

Source: http://books.google.com/books?id=Eey...bkFKE#PPA98,M1

[gym_rat]

Nice 1 mate
Just bought some BCAA's so most helpful!!