Amino Acids

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Supplemental Amino Acids: Gamma-Aminobutyric Acid (GABA), Glutamic Acid, Glutamine and Glutathione, Glycine, Histidine, Homocysteine

Gamma-Aminobutyric Acid

Gamma-aminobutyric acid (GABA) is an amino acid that acts as a neurotransmitter in the central nervous system. It is essential for brain metabolism, aiding in proper brain function. GABA is formed in the body from another amino acid, glutamic acid. Its function is to decrease neuron activity and inhibit nerve cells from over firing. Together with niacinamide and inositol, it prevents anxiety- and stress-related messages from reaching the motor centers of the brain by occupying their receptor sites.

GABA can be taken to calm the body in much the same way as diazepam (Valium), chlordiazepoxide (Librium), and other tranquilizers, but without the fear of addiction. It has been used in the treatment of epilepsy and hypertension.

GABA is good for depressed sex drive because of its ability as a relaxant. It is also useful for enlarged prostate, probably because it plays a role in the mechanism regulating the release of sex hormones. GABA is effective in treat ing attention deficit disorder and may reduce cravings for alcohol. It is also thought to promote growth hormone secretion.

Too much GABA, however, can cause increased anxiety, shortness of breath, numbness around the mouth, and tingling in the extremities. Further, abnormal levels of GABA unbalance the brain’s message-delivery system and may cause seizures.

Glutamic Acid

Glutamic acid is an excitatory neurotransmitter that in-creases the firing of neurons in the central nervous sys-tem. It is a major excitatory neurotransmitter in the brain and spinal cord. It is converted into either glutamine or GABA.

This amino acid is important in the metabolism of sugars and fats, and aids in the transportation of potassium into the spinal fluid and across the blood-brain barrier. Al though it does not pass the blood-brain barrier as readily as glutamine does, it is found at high levels in the blood and may infiltrate the brain in small amounts. The brain can use glutamic acid as fuel. Glutamic acid can detoxify ammonia by picking up nitrogen atoms, in the process creating another amino acid, glutamine. The conversion of glutamic acid into glutamine is the only means by which ammonia in the brain can be detoxified.

Glutamic acid helps to correct personality disorders and is useful in treating childhood behavioral disorders. It is used in the treatment of epilepsy, mental retardation, muscular dystrophy, ulcers, and hypoglycemic coma, a complication of insulin treatment for diabetes. It is a component of folate (folic acid), a B vitamin that helps the body break down amino acids. Because one of its salts is monosodium glutamate (MSG), glutamic acid should be avoided by anyone who is allergic to MSG.


Glutamine is the most abundant free amino acid found in the muscles of the body. Because it can readily pass the blood-brain barrier, it is known as brain fuel. In the brain, glutamine is converted into glutamic acid which is essential for cerebral function and vice versa. It also increases the amount of GABA, which is needed to sustain proper brain function and mental activity. It assists in maintaining the proper acid/alkaline balance in the body, and is the basis of the building blocks for the synthesis of RNA and DNA. It promotes mental ability and the maintenance of a healthy digestive tract.

When an amino acid is broken down, nitrogen is re-leased. The body needs nitrogen, but free nitrogen can form ammonia, which is especially toxic to brain tissues. The liver can convert nitrogen into urea, which is excreted in the urine, or nitrogen may attach itself to glutamic acid. This process forms glutamine. Glutamine is unique among the amino acids in that each molecule contains not one nitrogen atom but two. Thus, its creation helps to clear am-monia from the tissues, especially brain tissue, and it can transfer nitrogen from one place to another.

Glutamine is found in large amounts in the muscles and is readily available when needed for the synthesis of skele-tal muscle proteins. Because this amino acid helps to build and maintain muscle, supplemental glutamine is useful for dieters and bodybuilders. More important, it helps to pre-vent the kind of muscle wasting that can accompany pro-longed bed rest or diseases such as cancer and AIDS. This is because stress and injury (including surgical trauma) cause the muscles to release glutamine into the blood-stream. In fact, during times of stress, as much as one third of the glutamine present in the muscles may be released. As a result, stress and/or illness can lead to the loss of skeletal muscle. If enough glutamine is available, however, this can be prevented.

Supplemental L-glutamine can be helpful in the treatment of arthritis, autoimmune diseases, fibrosis, intestinal disorders, peptic ulcers, connective tissue diseases such as polymyositis and scleroderma, and tissue damage due to radiation treatment for cancer. L-glutamine can enhance mental functioning and has been used to treat a range of problems, including developmental disabilities, epilepsy, fatigue, impotence, depression, schizophrenia, and senility.

It preserves glutathione in the liver and protects that organ from the effects of acetaminophen overdose. It enhances antioxidant protection. L-glutamine decreases sugar cravings and the desire for alcohol, and is useful for recovering alcoholics.

Many plant and animal substances contain glutamine, but cooking easily destroys it. If eaten raw, spinach and parsley are good sources. Supplemental glutamine must be kept absolutely dry or the powder will degrade into ammonia and pyroglutamic acid. Glutamine should not be taken by persons with cirrhosis of the liver, kidney problems, Reye’s syndrome, or any type of disorder that can result in an accumulation of ammonia in the blood. For such individuals, taking supplemental glutamine may only cause further damage to the body. Be aware that although the names sound similar, glutamine, glutamic acid (also sometimes called glutamate), glutathione, gluten, and monosodium glutamate are all different substances.


Like carnitine, glutathione is not technically one of the arnino acids. It is a compound classified as a tripeptide, and the body produces it from the amino acids cysteine, glutamic acid, and glycine. Because of its close relationship to these amino acids, however, it is usually considered to gether with them.

Glutathione is a powerful antioxidant that is produced in the liver. The largest stores of glutathione are found in the liver, where it detoxifies harmful compounds so that they can be excreted through the bile. Some glutathione is released from the liver directly into the bloodstream, where it helps to maintain the integrity of red blood cells and protect white blood cells. Glutathione is also found in the lungs and the intestinal tract. It is needed for carbohydrate metabolism and appears to exert antiaging effects, aiding in the breakdown of oxidized fats that may con-tribute to atherosclerosis.

It can mitigate some of the damage caused by tobacco smoke because it modifies the harmful effects of aldehydes, chemicals present in cigarette smoke that damage cells and molecules, and it may protect the liver from alcohol-induced damage.

A deficiency of glutathione first affects the nervous system, causing such symptoms as lack of coordination, mental disorders, tremors, and difficulty maintaining balance. These problems are believed to be due to the development of lesions in the brain. A study sponsored in part by the National Cancer Institute found that people with HIV disease who had low glutathione levels had a lower survival rate over a three-year period than those whose glutathione levels were normal. As we age, glutathione levels decline, although it is not known whether this is because we use it more rapidly or produce less of it to begin with. Unfortunately, if not corrected, the lack of glutathione in turn ac celerates the aging process.

Supplemental glutathione is expensive, and the effectiveness of oral formulas is questionable. To raise glutathione levels, it is better to supply the body with the raw materials it uses to make this compound: cysteine, glutamic acid, and glycine. The N-acetyl form of cysteine, N-acetylcysteine (NAC), is considered particularly effective for this purpose.


Glycine retards muscle degeneration by supplying additional creatine, a compound that is present in muscle tissue and is utilized in the construction of DNA and RNA. It improves glycogen storage, thus freeing up glucose for energy needs. It is essential for the synthesis of nucleic acids, bile acids, and other nonessential amino acids in the body.
Glycine is used in many gastric antacid agents. Because high concentrations of glycine are found in the skin and connective tissues, it is useful for repairing damaged tissues and promoting healing.

Glycine is necessary for central nervous system function and a healthy prostate. It functions as an inhibitory neurotransmitter and as such can help prevent epileptic seizures. It has been used in the treatment of manic (bipolar) depression, and can also be effective for hyperactivity.

Having too much of this amino acid in the body can cause fatigue, but having the proper amount produces more energy. If necessary, glycine can be converted into the amino acid serine in the body.


Histidine is an essential amino acid that is significant in the growth and repair of tissues. It is important for the maintenance of the myelin sheaths, which protect nerve cells, and is needed for the production of both red and white blood cells. Histidine also protects the body from radiation dam age, helps lower blood pressure, aids in removing heavy metals from the system, and may help in the prevention of AIDS.

Histidine levels that are too high may lead to stress and even psychological disorders such as anxiety and schizophrenia; people with schizophrenia have been found to have high levels of histidine in their bodies. Inadequate levels of histidine may contribute to rheumatoid arthritis and may be associated with nerve deafness. Methionine has the ability to lower histidine levels.

Histamine, an important immune system chemical, is derived from histidine. Histamine aids in sexual arousal.

Because the availability of histidine influences histamine production, taking supplemental histidine together with vitamins B3 (niacin) and B6 (pyridoxine), which are required for the transformation from histidine to histamine may help improve sexual functioning and pleasure.

Because histamine also stimulates the secretion of gastric juices, histidine may be helpful for people with indigestion resulting from a lack of stomach acid.

Persons with manic (bipolar) depression should not take supplemental histidine unless a deficiency has been identified. Natural sources of histidine include rice, wheat, and rye.


Homocysteine is an amino acid that is produced in the body in the course of methionine metabolism. This amino acid has been the focus of increasing attention in recent years, because high levels of homocysteine in the blood are associated with an increased risk of cardiovascular disease.

Further, it is known that homocysteine has a toxic effect on cells lining the arteries, makes the blood more prone to clotting, and promotes the oxidation of low-density lipoproteins (LDL, the so-called “bad cholesterol”), which makes it more likely that cholesterol will be deposited as plaque in the blood vessels.

Like other amino acids, homocysteine does perform a necessary function in the body. It is then usually broken down quickly into the amino acid cysteine and other important compounds, including adenosine triphosphate (ATP, an im portant source of cellular energy) and Sadenosylmethionine (SAMe). However, a genetic defect or, more commonly, de ficiencies of vitamins B6 and B12 and folate (folic acid) can prevent homocysteine from converting rapidly enough. As a result, high levels of the amino acid accumulate in the body, damaging cell membranes and blood vessels, and increasing the risk of cardiovascular disease, particularly atherosclerosis. Vitamins B6 and B12 and folate work together to facilitate the breakdown of homocysteine, and thus help protect against heart disease.

About the author: Georgiy Kharchenko with American Weight Loss Group LLC selling: Weight Loss Pills, ECA STACK, Phentramin D, lipodrene


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100 Responses to Amino Acids

  1. political_maester says:

    How are amino acids connected in a lab?
    I want to do a little science experiment and make my own complex molecules at home. Amino acids are readily available as vitamin supplements (all 20 of them). What I need to know is what chemicals to use to make chains with them. Any help is greatly appreciated.

    Also, if you didn’t know, all amino acids have a carboxylic acid group and a primary amine group, if this helps with an answer.

    • Aldo says:

      the subject of protein synthesis is very extensive to dicuss in this forum. There are many chemicals used, like boc and fmoc, Sanger’s reagent, etc. So, I strongly suggest reading any good biochem book or online resource.

      In any case, general method of synthesis requires the following general, non-exclusive steps. Bind the starting or chosen “left end amino acid” to a particular inert substrate. This leaves the other part of the amino acid to react. Then “deactivate’ with a number of chemicals reagents, the N terminal of the amino acid. After the formation of the peptide bonds, the peptide is treated with another set of chemicals like TFA(triflouroacetic acid) to remove the “deactivators”.

      It is worth mentioning that the synthesis is pH dependent. Also check in what form ( as chloride, tartrate, succinate, etc) the amino acids are in your vitamin bottle.

  2. Angel of Dorkness says:

    How do I easily separate a mixture of amino acids from a digest? And then purify them individually?
    How do I easily separate a mixture of amino acids from a digest? And then purify them individually? The primary amino acids in the digested mixture are phenylalanine, alanine, aspatatic acid.
    Captain: For 1, I’m not using a busen burner, and two, I’m a dork. Dorks can’t get girls. But thats off topic. The question still stands.

  3. :::♥:::Castle:::♥::: says:

    What is the difference between amino acids and protein?
    How do amino acids differ from proteins? Where do Enzymes come into the pictures?

  4. Chad says:

    Can someone simply break down for me why Amino Acids are important for weight lifters?
    I am well aware of how big a roll protein plays in strenght gains and muscle mass and I make sure I get alot of protein everyday. What I dont know is what Amino Acids do. Do they just give you more energy for more of an intense workout or what? Thats what things like creatine are right?

    • Dr Dave says:

      Amino acids are what make up protein. When you workout, you damage your muscles and they need to be repaired. When you take a protein shake or consume any protein, your body breaks it down and uses the amino acids to repair the muscle. Also, muscles are always breaking down and rebuilding, so even if you don’t workout, so you always need to consume protein.

      Creatine does not have amino acids in it, protein does…

  5. Jane D says:

    What is the sequence of amino acids coded for by the mRNA codons?
    Can someone please explain how to do the following problem?

    The following base sequence represents part of a normal mRNA strand:


    Write is the sequence of amino acids coded for by the mRNA codons.
    Assuming that the change in the mRNA actually resulted from a mutation in the DNA, what would the entire DNA sequence of triplets be? Circle the mutated DNA base.

    • Alone GuY says:


      Amino acid sequence – Start(Met) -Trp- Stop

      The translation will be terminated at the third codon as its a stop codon.

  6. Mia Forsyth says:

    How do amino acids work when they’re in diet pills?
    I found these amino acid pills in the cupboard today and the bottle said they were diet supplements. How do they work as diet supplements? Like do they make you eat less or are they like laxatives? Also is 4 1000 (I don’t know if it’s mg or what) tablets too much? Because the bottle said to take 4 a day. It also says it’s a balanced blend of 20 amino acids. So what does this all mean?

    • Mich Levesque says:

      Diet supplements” are different from “Diet Pills”

      Supplements are vitamins, essentially. They are taken to supplement (replace) the vitamins, or in this case, amino acids, that you may not be getting in your day-to-day diet (not meaning to lose weight, just meaning what you eat)

      Diet pills are (a hoax) supposed to help decrease appetite, make you poop, less water retention etc… they don’t work though. Sorry.

      Now to answer your question about aminos…

      Below is a list of some of the ways that amino acids have been used.

      Arginine – has been shown to improve sperm count and sperm motility in some men.

      Lysine – is used particularly for recurrent cold sores and herpes infections.

      Phenylalanine – has been used in the treatment of pain and depression.

      Tryptophan – this amino acid has been more studied than the others. There is an association between the level of tryptophan in the blood and arthritis. High levels of tryptophan are also found in jaundice. It has also been used in depression, particularly if insomnia is present. Oestrogen containing oral contraceptives interfere with the normal metabolism of tryptophan (this may be because of their effect in vitamin B6 which is essential for the conversion of tryptophan to serotonin.)

      Histidine – has been used in rheumatoid arthritis – low levels of histidine has been found in the blood of those with rheumatoid arthritis

      Tyrosine – like tryptophan and phenylalanine has been used in the treatment of depression. This amino acid is essential for the synthesis of substances called catecholamines (these include dopamine and noradrenaline) and some people who are depressed have low levels of these compounds.
      It is likely that more and more uses for amino acids will become evident as research progresses.

      Proteins (which contain amino acids) are essential requirement in our diet. Amino acids, essential and non-essential, are needed for the body’s structural component – bones, muscle and connective tissue and for functional aspects such as hormones and other chemicals. The range of therapeutic used for which amino acids are used is still somewhat limited it is likely that the uses will expand as we learn more about the role that amino acids play in maintaining health.

  7. nauman535 says:

    How many naturally occuring unusual amino acids are present in proteins?
    There are 20 common amino acids that occur in all proteins. I need to know naturally occuring unusal amino acids apart from 20 common amino acids.

    • novangelis says:

      There are a number.

      Directly incorporated:
      N-formyl methionine, not methionine starts bacterial proteins.
      Selenocysteine is directly incorporated into protein chains
      Pyrrolysine is found in proteins of some methanogens

      Modified after incorporation into the protein chain:
      Proline is modified to hydroxyproline in collagen.
      Glutamate is changed to carboxyglutamate in some clotting factors.
      Phosphorylation of tyrosine is an important signaling pathway (tyrosine kinases).

      Attachment of a variety of groups to amino acids — post-translational modification — would make the list extremely long.

  8. Dill says:

    What is the complete sequence of amino acids in this polypeptide?
    On complete hydrolysis a polypeptide gives 2 alanine, one leucine, one methionine, one phenylalanine and one valine residue. Partial hydrolysis gives the following fragments: Ala-P, Leu-Met, Val-Ala, Phe-Leu. It is known that the first amino acid in the sequence is V aline and the last one is Methionine.
    1. What is the complete sequence of amino acids in the polypeptide?
    2. If the first amino acid is alanine and the last one is also alanine, what is the complete sequence?

    • steve_geo1 says:

      I suppose that the first dipeptide from partial hydrolysis is Ala-Phe.

      One problem is that you don’t know yet whether Val-Ala is the same Ala as that in Ala-Phe, so leave that for a moment.

      You have Phe-Leu, so part of the sequence must be Ala-Phe-Leu.

      You have Leu-Met, so that makes it Ala-Phe-Leu-Met.

      So you go on until you build up the whole sequence of six.

  9. Jacquline M says:

    amino acids?
    how can two protiens with the exact same number and type of amino acids have different primary structures?

    • steve_geo1 says:

      Consider glycine (gly), alanine (ala), and valine (val). Four of the several possibilities are:

      Gly-Ala-Val Gly-Val-Ala Val-Ala-Gly Val-Gly-Ala

      But they’re all different. Draw out the molecular structures and you’ll see.

  10. Bill. says:

    What are two examples of different properties that amino acids can have?
    Amino acids have different chemical properties. What are two examples of different properties they can have?

    • Oops! Unsure housewife! says:

      Polar vs. Nonpolar (Tryptophan vs. Isoleucine)
      Charged vs. Uncharged (Aspartic Acid vs. Leucine)
      Negatively charged vs. Positively Charged (Glutamic Acid vs. Lysine)
      Forms Disulfide bridges – Cysteine

  11. balanced112 says:

    Which amino acids should i buy to help increase muscle recovery and muscle growth?
    I am taking whey protein, however i heard BCAAs are good and some other amino acids. Does anyone have a specific product that i should buy or a combination of amino acids that is effective to take pre/post workouts. Thank you!

  12. Joe B says:

    Amino acids?
    Can someone please give me a summary comparing and contrasting the variety of amino acids with that of monosaccharides and fatty acids? Which group exhibits the greatest structural variability and why/how?

    • steve_geo1 says:

      They truly all exhibit a great variety of structural variability. I think that your teacher wants you to say that amino acids give greatest variety, because there are 22 of them, and they can be combined in all combinations and permutations.

      Next, your teacher is cheating a little. S(he) specifies fatty acids, which are esterified with glycerol. But S(he) does not specify which fatty acids (there are many) nor does s(he) tell how many (there are several possibilities) are esterified with each glycerol.

      Next, your teacher cheats by specifying monosaccharides, like glucose, fructose, and galactose. This leaves out table sugar (glucose-fructose), milk sugar (glucose-galactose) and the kajillions of polysaccharides that coat the cell walls of bacteria that are recognized by antibodies in the immune system. It also leaves out the starch, glycogen, cellulose, cotton, linen, and wood that make up much else in the world.

  13. mr_kevo2 says:

    How important are amino acids in weight lifting?
    I am looking to gain muscle mass and gain weight. I take supplements like whey, creatine and NO and i was just wondering how important amino acids are in order to acheive my goal of gaining weight and muscle mass. Basicly im wondering whether or not to buy amino acid capsules along and add them with the other supplements i take. Thanks

    • carcaya888888 says:

      Exactly as stated before – Proteins are made of chains of amino acids. Our bodies break down foreign proteins into Amino Acids and use them to build the proteins that make up our lean body mass. So giving your body Amino Acids just takes out the breaking down step that your body has to do.

      What I would suggest is that you take Optimum Nutrition (ON) whey protein which has BCAA’s (a type of amino acid) in its formula already as your whey supplement. I wouldn’t worry about the capsules. Plus any stand alone Amino Acids taste horrible.

      BTW I love Gaspari Nutrition products, they have helped me yield significant gains. You should look them up. Super pump 250 + Size On

  14. You Know What?! says:

    What amino acids stay in the wort for the yeast to use?
    You know what, amino acids are needed by yeast just for normal health and stuff which ones are in the wort. So are the ones which are needed by yeast in the wort?
    Wort is a sweet solution made from steeping grain in hot water, washing it with fresh hot water, and collecting it. Later it is fermented by yeast.

    • BEER says:

      Nineteen that I know of with eight being essential amino acids. I will list the essential AA only.
      Isoleucine, leucine, lysine, methionine, phenylalanine, threinine, tryptophane, valine

      The benefit for use of a nutrient is a faster onset fermentation {reduced lag phase}, more vigorous fermentations and improved and reliable attenuation rates.

      You are right that yeast needs nitrogen in the form of amino acids (AA). The yeast will use AA for building strong membranes and helps it to reproduce (budding) at greater rates. Lipids (fats), in the form of sterols, are also critical to yeast’s outer cell wall. {This does NOT mean that beer contains fat.} The result is a better ferment and thus a better beer or wine. They will also help in enzymatic activity*. The enzymes produced by yeast are used for nutrient uptake once again aiding yeast health. The kicker for you big beer buffs is that good AA levels help yeast stand up to higher levels of alcohol. Go health yeast then helps it to produce higher level of alcohol [yeaA!]. Yeast nutrient delivers the AA via phosphate.
      Nutrient mixes in addition to AA’s should also contain an assortment of vitamins, minerals like zinc and trace elements.
      Yeast energizer may be a good choice in certain situations. The difference between yeast nutrient and yeast energizer is the nitrogen or AA source. With the nutrient the AA usually comes from one source while the energizer has many AA contributors. The nutrient should only be needed if making a high adjunct brew and sometimes with extract brews. Yeast nutrient is more commonly used in certain nutrient deficient wines. Keep in mind that many suppliers use the terms nutrient and energizer interchangeably so if your need for accuracy is high be sure to get clarity.

      The Technuical Fluff
      *Yeast produced enzymes also contribute to the clarity of beer and wine.
      DAP (Diammonium Phosphate, {NH4) 2HPO4.} – 1 g/L is about 258 mg/L free use N.

      ** Wine makers it is important to use a good yeast nutrient.
      Yeast Energizer contains yeast natual products/extracts in the form of proteins, B1 Vitamin (B’s), and di-ammonium phosphate. Each are AA sources.

  15. num1grl says:

    Amino Acids?
    Help, please help me answer ANY OF the questions. I am clueless
    (a) List the names of the two functional groups you will find in all amino acids.
    (b) Name all amino acids whose R side chain contains a sulfur atom.
    (c) Name all amino acids whose R side chain contains is aromatic.
    (d) Are polypeptide chains formed from addition or condensation polymerization

    • Wyk123 says:

      a) -COOH , -NH2

      b)cysteine , methionine

      c)phenyl alanine , Tryptophan , Tyrosine

      d)condensation polymerization

  16. AO says:

    How many amino acids does the body really contain?
    My Science teacher told us to find the 23 amino acids found in the body. Everywhere I have looked there is only 20 necessary amino acids. Can anybody help me answer this?

    • Dr. Radan S says:

      The above answer is NOT correct!
      There are hundreds of different amino acids found in the body. Remember and amino acid is a carboxylic acid with an amino group.
      Hear are some examples of amino acids which are NOT one of the 20 so called “proteinogenic” amino acids
      1. GABA (gamma-aminobutyric acid) – the most common inhibitory neurotransmitter in the brain
      2. Ornithine and Citrulline – both are found in the urea cycle, in addition, citrulline is present in certain protein, such as mylein basic protein (MBP)
      3. Although proline and lysine are among the 20 amino acids, but they are hydroxylated to hydroxyproline and hydroxylysine, a process requiring iron and vitamin C, and is important ion the synthesis of collagen.
      4. Taurine – found in bile ( a constituent of bile salt), in the brain as a neurotransmitter, in cells which helps protect cells from oxidative stress, etc.
      5. Lanthonine is found in human hair and in the feather of birds
      There are many, MANY more!
      To say that there is only 20 “necessary” amino aids is a big miss-nomer. There are only 20 amino aids code for by our genes, but amino acids such as GABA and Taurine are vital. ie. if you use a poison such as picrotoxin or barbiturates, you will inhibit the inhibition in your brain and cause seizures, convulsions and respiratory arrest!

  17. Andy H says:

    What are amino acids and how are they created?
    Are amino acids just protein that hasn’t been wound yet? Or are amino acids the RNA chains that are created in protein synthesis? How do they relate to the creation of proteins in protein synthesis?

    • jenny79 says:

      Amino acids are the building blocks of proteins. They band together in chains to form the stuff from which your life is born. Think of amino acids as Legos for your life.

      It’s a two-step process: Amino acids get together and form peptides or polypeptides. It is from these groupings that proteins are made. And there’s not just one kind of amino acid.

      total of 20 different kinds of amino acids form proteins. The kinds of amino acids determine the shape of the proteins formed. Commonly recognized amino acids include glutamine, glycine, phenylalanine, tryptophan, and valine. Three of those — phenylalanine, tryptophan, and valine — are essential amino acids for humans; the others are isoleucine, leucine, lysine, methionine, and threonine. The essential amino acids cannot be synthesized by the body; instead, they must be ingested through food.

      One of the best-known essential amino acids is tryptophan, which performs several critical functions for people. Tryptophan helps induce normal sleep; helps reduce anxiety, depression, and artery spasm risk; and helps produce a stronger immune system. Tryptophan is perhaps most well-known for its role in producing serotonin, which is what gets all the press at Thanksgiving time for putting you to sleep after the big holiday feast.

      Amino acids make up 75% of the human body. They are essential to nearly every bodily function. Every chemical reaction that takes place in your body depends on amino acids and the proteins that they build.

      Essential fatty acids and amino acids are two different things. Fatty acids are the basic building blocks of fats (or lipids) while amino acids are the building blocks of proteins.

      The essential amino acids must be ingested every day. Failure to get enough of even one of the 10 essential amino acids can result in protein degradation. The human body simply does not store amino acids for later use, as it does with fats and starches. You can find amino acids many places in nature. In fact, more than 300 have been found in the natural world, from such diverse sources as microorganisms and meteorites.

  18. Shea Dawn says:

    What mutations change the sequence of amino acids and do not change amino acids in an encoded protein?
    Give examples both of: a mutation that does change the sequence of amino acids in the encoded protein, and a mutation that does not change the sequence of amino acids.

    • ZooKid6 says:

      A neutral mutation does NOT change the amino acid coded for by a codon. An example is that the RNA codon for proline could be CCC, CCU, CCG, or CCA. A mutation in that third position, then, is neutral.

      A non-neutral mutation changes the amino acid coded for by a codon. An example is that AAC codes for asparagine. If it mutates to AAA, then it codes for lysine.

  19. philly cheese says:

    How do vegetarians get enough amino acids to build muscle?
    I’m trying to make sure that i get enough amino acids to build muscle after i work out, but i don’t know which vegetarian foods have enough amino acids to do this. Any insights?

    • crazy_random says:

      they eat nuts. it doesn’t work on most people because i know a girl who was vegetarian but later turned vegan and from the lack of vitamins, she now has a blood disorder. she sings good, though.

  20. I have a question says:

    How many essntial amino acids are there?
    How many essential amino acids are there?
    And how many of them are not essential?

    (My teacher said I should have a list of them?)

    She also asked us which of those amino acids do we have to eat to stay healthy?

    • OKIM IM says:

      8 are essential.

      12 are non-essential.

      The 8 essential ones have to be eaten, because we can not make them.

  21. says:

    What happens if the amino acids that are found in the interior of a protein?
    What happens if the amino acids that are found in the interior of a protein are forced to be exposed to the the surface of the protein? These interior protiens are hydrophobic amino acids.

    • Sparrow says:

      If the protein is in an aqueous (polar) solution, the protein will automatically refold so that the hydrophobic amino acids are not in contact with the polar environment.

  22. E D says:

    If a patient is given amino acids, what might this be for?What are amino acids made of?
    In the hospital if a patient is given amino acids through an IV what might this be for, and what are the amino acids synthesized from or procured from?

    • Argie85 says:

      Like some of the other answerers I agree. Aminoacids are part of proteins and they are needed to produce them. Let’s not forget that some aminoacids like glutamate and glycine are also neurotransmitters, and there are multiple examples of uses of the aminoacids per se (not as proteins or peptides)
      The number of types of aminoacids has relative value. There’s some controversy as to how many of each the human body can produce. 20 is the number of aminoacids that are coded in DNA. There are almost 300 in nature and more than those 20 aminoacids within our body (derived from other aminoacids, like those in the urea cycle). In Harper’s biochemistry there are 11 quoted as essential aminoacids (meaning we need to ingest them, because we can’t produce them, or we produce very little, not enough according to our needs), but in different text they explain much more that some of them are required in different stages in our lives more than others.
      As one of the answerers said, the IV use of aminoacids could be to supplement a deficiency in diet or nutrition of the patient. Those aminoacids can be obtained artificially or from different organic products. It’s not the best way to supply aminoacids, unless the patient can’t ingest proper food.

  23. SunshineDazzles says:

    How many codons are needed to specify 3 amino acids if one codon is required to specify one amino acid?
    How many codons are needed to specify 3 amino acids if one codon is required to specify one amino acid?

    This is for a very important test. Review. Thanks.

  24. Kalesa says:

    How do I get the amino acids in a 3D protein model interacting?
    For school, I’m suppose to make a protein model using copper wire and coloured paper. I have all of the “amino acids” attach but the problem is I’m unsure how they are supposed to interact. Help?

    • sci219 says:

      For this, I will gve you a few points:
      1.) alpha helixes form first, then beta-sheets.
      2.) for beta-turns, it is mostly P and G amino acids.
      3.) For alpha helix, the carbonyl of the polypeptide backbone hydrogen bonds to the hydrogen of the amino group (usually about 11 atoms from the carbonyl). Hydrogen bonds hold the alpha helix together. The R-groups face on the oustide of the helix.
      4.) Cystine forms disulfide bridges. C-S-S-C
      5.) mostly hydrophobic amino acids like V, A, L, I, M, and others face towards the inside of the protein and hydrophilic amino acids like E, D, Y, T, S, and others face towards the outside of the protein.
      6.) Ionic interactions form bewteen + and – charges. For example:
      K interacting with D via charges. K has a + NH3 and D has a – oxygen.
      These a re called salt bridges.
      7.) You also have hydrogen bonding and van der waal interactions.

      Let me know if you need any more help.
      good luck.

  25. Dude says:

    What amino acids are essential to most protein folds?
    Also, what amino acids are not essential to a significant number of protein folds?

  26. smarti pants says:

    How many different kinds of amino acid sequences can you make if you have 10 amino acids in a chain?
    I need help. I forget the formula I need to convert this. So if there are to be 10 acids in a chain and there are 20 amino acids in the human body, how many combinations can one make? Please show formula and work. Thanks.

    • misoma5 says:

      20^10 or 10.24 trillion different peptides.10240000000000 combinations. Wobble effect doesn’t play into this because you are starting with amino acids, not mRNA..

  27. Clouds says:

    Are all of the Amino acids found in some kind of food? If your vegetarian and you want Amino Acids?
    Are these Amino Acids the same as the general term “Protein” ?

    And when you buy bottles of Amino Acids, can you take these or find these in foods? Are some Amino Acids found in no foods? Are Amino Acids found in Plants as often as animal products, if you are vegetarian?

    • mockingbird says:

      Amino acids are the building blocks of protein. Of the 22 or so amino acids that your body needs to function, all but 8-10 are created by the body. The ones that are not are called essential amino acids and have to be gotten from the diet. ALL essential amino acids are provided by plant foods. The ONLY difference between animal proteins and plant proteins is the concept of completeness. Meat has all the essential amino acids in one food; plant foods are rarely* complete, so you have to eat a variety of them to get all your requirements. This is a moot point, though, because EVERYONE (meat eaters included) needs to be eating a variety of plant foods for all of their other nutritional requirements anyway. You do not need to buy bottles of amino acids and you do not need to take protein supplements; just eat a balanced, varied diet and get enough calories to meet your energy needs and you will have plenty of protein. It is never recommended to take individual amino acids unless you’ve been diagnosed with a deficiency.

      *Soybeans and quinoa are complete plant proteins.

  28. mewichigo94 says:

    What is the degree that certain amino acids can participate in the alpha helix structure of proteins?
    I’m confused about what that exactly is, and where to find it for certain amino acids (arginine, glycine, glutamic acid and lysine).
    And also; is pKa a physical or chemical property? And is the referred question a physical or chemical property?

  29. peterk says:

    How do amino acids interact in the tertiary structure of a protein?
    Hi, any help will be much appreciated.

    Which of the following amino acids could tyrosine interact with in the tertiary structure of the protein? More than one answer could be right.

    A) Glycine
    B) Serine
    C) Glutamic acid
    D) Valine
    Glutamic acid:

    • greendawn says:

      They interact through four different kinds of forces between the amino acid side chains:

      Disulfide bonds between two cysteines.

      Hydrogen bonds usually between alcohols and/or acids and alcohols with amines.

      Salt bridges resulting from the tansfer of a proton from carboxylic acid to an amine group. The former becomes negative the latter positive so there is an ionic attraction between them.

      Tyrosine contains a hydroxyl (alcohol) group in its sidechain which can interact with the hydroxyl group of serine to form a hydrogen bond.

  30. Brendd says:

    How is it possible for just 20 amino acids to make proteins that could express many traits?
    This is the Real Question:

    Humans have 25,000 traits.
    How is it possible for just 20 amino acids to make proteins that could express that many
    traits when we know that one protein can only express one trait?

  31. linda says:

    What are the bonds that hold amino acids together to make a protein?
    What are the bonds that hold amino acids together to make a protein? Please help!

  32. N G says:

    What is a Hydrogen donor and acceptor when talking about amino acids?
    In my notes, it says that aspartate, glutamate, asparagine, and glutamine are some examples of amino acids that are Hydrogen donors. Lysine, arginine, and histidine are examples of acceptors. What is it about these amino acids that makes them this way? Please talk about their molecular structure, whatever polarities they might have, charges, etc.

    • derbedog says:

      K when talking about proteins, their are three different structures that a protein can be based on the R group attached to the basic carbon skeleton. The first group or the polar group is the group that consists of amino acids like Serine, Threonine, Cysteine, Tyrosine, Asparagine and Glutamine. They are polar, which means they are hydrophilic. The others are electrically charged amino acids based on a charged R group. Examples of these are Aspartic Acid, Glutamic Acid, (These two are acidic) Lysine, Arginine, Histidine. (These three are basic). What would make these charged amino acids hydrogen acceptors is that they have an exposed oxygen atom which is negatively charged and wants a hydrogen to create a hydroxyl group. Hope this helped

  33. dre says:

    What formula would you use to figure out how many amino acids a protein contains?
    Given the molecular weight of a protein=55,000

    How many amino acids does the protein contain, assuming that the average molecular weight of an amino acid is 120.

    I am NOT looking for the answer here, I am trying to figure out how to solve this problem to better understand this section in class. Thanks!

  34. jmark_hagan says:

    Does anybody know what the affects of amino acids on a diabetic? Can amino acids make your sugar drop?
    My sugar dropped the other day and the nurse seems to think that it is the Amino 3000 that I have been taking for almost two months. Do amino acids have an effect on diabetics?

    • essentiallysolo says:

      amino acids are building blocks used by the body to repair damage, so if you have repaired something and your body is running more efficiently, it stands to reason that you would burn your available sugars more efficiently and thereby drop your blood sugar levels.

  35. AN14 says:

    How do you figure out amino acids from the genetic code chart?
    Here’s the chart:

    How do you read the chart and figure out the amino acids? Please give answers that are as straightforward and as easy to understand as possible.

    I really need help with this to prepare for a test.

    Thanks in advance!

    • Dr. Lopez says:

      To use the genetic code chart (or codon chart) you provided you need to take your codon (3 letter RNA sequence) and begin in the center of this chart:

      1. Match the first letter of your codon to one the four big, inside letters (A, C, G, or U)
      – Now you will be working only with that “quarter” of the chart
      2. Match the second letter of your codon to the next set of letters in that “quarter”
      – Now you will be working only with that “section” of that “quarter”
      3. Match the thrid letter of your codon to the last set of letters (in bright yellow)
      4. The corresponding amino acid (those names on the perimeter) is what will be encoded by your codon.

      Example: The codon UUG will encode for Leucine. Hope this helps!
      please visit my BioBlog @

  36. Samantha T says:

    When a patient is given amino acids through IV in the hospital, which amino acids are in the solution?
    Is Cysteine or, n-acetyl l-cysteine one of them?


    are there different sets of solutions of amino acids the hospital might administer to various patients on amino acids?

    • Marie says:

      Interesting question!

      Yes, there are different solutions depending on what we are treating and why. The requirements vary overall for children as opposed to adults, and there are also specific amino acid solutions for people who have genetic issues with the ingestion of certain amino acids.

      There are ten amino acids that are generally considered to be “essential”: Phenyalanine, histadine, isoleucine, leucine, lysine, methionine, tryptophan, arginine, threonine and valine. Those would be necessary unless contraindicated for medical reasons. Children are also considered to require cysteine, glycine, glutamine, serine and tyrosine.

      N-acetyl-cysteine (a derivative of cysteine with an acetyl group attached to the nitrogen) is also used as an antidote for acetominophen poisoning. We wouldn’t use that for nutrition. We also give it to kids with cystic fibrosis to help break up the phlegm in the lungs and respiratory tract.

      You can Google Aminosyn or Travasol if you want specifics on particular formularies; those are the two I’m familiar with.

      ETA: Just to clarify what the next poster said, cystic fibrosis is most commonly caused by a mutation that involves a three-nucleotide deletion on a particular gene (named the CFTR gene, for cystic fibrosis transmembrane regulator). The job of any gene is to make a protein, in this case CFTR, which happens to be a chloride channel found in the lungs and the GI tract.

      Nucleotides are the building blocks of DNA and there are four of them (guanine, adenosine, thymine and cytosine–G, A, T and C). In genetic terms, each amino acid that is added to a protein is coded for by a “word” made by three nucleotides on a gene. So if you delete those three nucleotides, you lose that one amino acid being added and in the case of CF, that makes that chloride channel not work properly and that causes the symptoms of CF, because part of its normal job is to make the secretions in the lungs more liquid and easily expelled. CF patients have very thick mucus that is difficult to cough out, which leads to lots of infections in the lungs. (This is HUGELY oversimplified, of course.)

      However–and I do have a point here, I promise–that has nothing at all to do with dietary phenylalanine and giving CF patients phenylalanine will not correct the problem. Phenyalanine will never be added to that protein in the correct position unless we come up with a way of doing it genetically (and we’re trying). The fact that we give NAC to CF patients is just because it happens to act as an enzyme to help break down secretions in the lungs–it’s incidental that it also happens to be an amino acid.

  37. Joe Z says:

    How are amino acids excreted from the body?
    I’m aware that proteins can be deaminated, producing a hydrocarbon and a nitrogenous molecule which is excreted through urine. Are there other ways? Is it common practice for kidneys to just excrete excess amino acids?

    • steve_geo1 says:

      No. The nitrogen is converted to urea through the ornithine metabolic cycle. Urea is the only nitrogen compound excreted in the urine.

      When the kidneys are failing, protein gets through into the urine: proteinuria.

      When amino acids are incompletely metabolized, as in the inborn error of metabolism phenylketonuria, phenylalanine is deaminated to phenylpyruvic acid, which cannot be metabolized further, and so spills into the urine. Unless detected and treated, the result is severe mental and physical retardation.

      Perhaps you have noted on the label of a can of diet soda sweetened with aspartame, “Phenylketonurics: Contains phenylalanine.”

  38. Neo says:

    How is it possible that amino acids can be repeated in a DNA sequence even codons in the mRNA are different?
    If i have for example:
    Amino acids: Met-Phe-Ala-Gly-Gly-Ser-Trp-Ala in a sequence how is it possible that the same amino acids get repeated altough the codons in mRNA is all different.
    who can explain?

    • Spandan says:

      Each codon codes for only one type of amino acid, but one type of amino acid may be coded by several codons. (it’s very important that you understand this). For e.g Leucine can be coded by UUA and UUG. But the codon UUA never codes for other amino acids except leucine.
      That is why it’s possible to get repeated amino acids though same codon is not repeated in mRNA.

      Hope this was understandable and of help 🙂

  39. N.S. says:

    What eating stuff is rich in omega 3, amino acids and fatty acids?
    I searched in google and I found following fishes to be rich in omega 3


    but I don’t think that any of these fishes are found in India…

    So what fishes which are found in India are rich in omega 3, amino acids and fatty acids?

    And also, what other vegetarian eating stuff is rich in omega 3, amino acids and fatty acids?

    Thanks in Advance!

    • Red says:

      Fresh or dried anchovies are also rich in omega-3s and proteins. But due to their smaller sizes, you’ll need to eat more of them. And for dried anchovies, be sure to soak and wash them thoroughly before cooking, as they are usually preserved with salt. Enjoy!

  40. podbijoko says:

    Are there any organisms that synthesize amino acids in a different way than us?
    As far as I know, all organisms have the amino acid “alphabet”- this triplet codes for this amino acid, and that triplet for that one. That’s why we are all presumed to come from a single cell.

    But are there any bacteria or something that use a completely different language, or system to make amino acids? Or, for that matter, are there any organisms that live by a completely different biochemistry than all other organisms?

    • Hello says:

      Some plants, trees lack ability to get nitrogen into proteins, amino acids. The rely on bacteria underground to ‘fix’ nitrogen into biomolecules. All living things basically have same foundation, DNA, proteins/enzymes…etc. And triplet codes is universal. Same for all living things.

  41. rustydogz1 says:

    What are 24 amino acids found in animal tissue?
    Of these 24 amino acids, which are essential? Where can I find their abreviations?

    I have searched for a while trying to find the answers, but have had no sucesses. My textbook does not list them.

    • rhodadat says:

      There are only 20 amino acids found in animals not 24.

      Humans and other mammals, however, can only synthesize half of them. They cannot synthesize isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. These are the essential amino acids, since it is essential to ingest them. Mammals do possess the enzymes to synthesize alanine, asparagine, aspartate, cysteine, glutamate, glutamine, glycine, proline, serine, and tyrosine, the nonessential amino acids. While they can synthesize arginine and histidine, they cannot produce it in sufficient amounts for young, growing animals, and so these are often considered essential amino acids.

  42. Samanosuke says:

    What are some good amino acids for bulking?
    Been in bodybuilding for about 5 years now. I don’t take anything except protein. I want to know what are some good creatines, amino acids, and testosterone boosters for bulking. Would be much appreciated.

    • VegasBoxer702 says:

      Amino acids are great and i get mine from optimum nutrition and instead of taking creatine i take a NO product that has creatine in it already. Super Pump 250 is a great product from Gaspari nutrition.

  43. Brian K says:

    How many possible different proteins could be made out of 141 amino acids?
    I really don’t know the formula, so I can’t find out how to do it. According to my book- just 4 amino acids linked together can have 160,000 possible combinations. How much would there be with a chain of 141 amino acids?

    • Big Daddy says:

      Assuming 20 amino acids and no restrictions on order, then you have 20 different monopeptides, 20×20 or 400 dipeptides, 20^4 or 160000 for runs of length 4.

      For a length of 141, it’s 20^141.
      That’s something like 2.8 x 10^183. A rather substantial number.

  44. Matt says:

    What vegetable gives all the essential amino acids?
    I remember from my biochem class that it is difficult to be a vegetarian because most non-animal sources of protein lack some of the essential amino acids. I know that if you eat a wide variety of vegetables/beans/etc that you can make up for this, but I seem to remember my professor telling us one specific vegetable/bean that provided all of the essential amino acids. Does anyone know what this is?

    • sandra_abernathy says:

      Beans and Rice, or Beans and Corn when eaten together, make a complete amino acid or a complete protien.

  45. hdang89 says:

    What are the two common amino acids found in mammalian proteins?
    I have to draw a dipeptide structure but I do not know what the 2 common amino acids in mammalian proteins are.

    • gribbling says:

      There are 20 amino acids found in mammalian proteins.

      The two encountered most frequently in vertebrate proteins are serine (8.1%) and leucine (7.6%)

  46. hmeustice says:

    How many amino acids are used to make all the proteins in the body?
    I know the monomers that make proteins are amino acids, but I’m supposed to know how many of them make up ALL of our body’s proteins.

    • novangelis says:


      Most proteins have the standard 20 incorporated, then some are modified (e.g. carboxyglutamate). There is one important exception — selenocysteine is directly incorporated into proteins such as glutathione peroxidase.

  47. Submission Magician™ says:

    When writing an amino acid sequence for a protein do you use the abbreviation of the amino acids or the codons?
    I have a project in which I have to create a hypothetical protein with 100 amino acids. I’m not sure how to write an amino acid sequence.

    • andy says:

      Amino acid sequence of a protein is written in the ONE letter code for each amino acid. For example, if you have a sequence like: Methionine Leucine Isoleucine Tryptophan Cysteine….
      The sequence should be written in the following manner:


  48. Aoiffe337 says:

    What role do amino acids play in reducing the body’s sweat?
    The body has nutrients with specific functions and amino acids is one of them. Does taking amino acids and vitamins,s reduce profuse sweating, especially at night?Sports drink are said to replenish the liquid lost but some say they are not good for one’s health? What can an individual do to reduce sweating and the amount of clothes changed frequently?

  49. N says:

    What is the maximum number of amino acids that could be in proteins?
    Suppose that in another world the code was a doublet code having four bases. What is the maximum number of amino acids that could be in proteins?

    • emucompboy says:

      How long is string? LOL. Poorly worded question, it can be interpreted two ways.

      The answer your teacher wants is
      16 different amino acids
      Since you have two positions (doublet) each of which can have four possibilities (bases) you have 4×4 = 16.

  50. joven v says:

    What group of amino acids or protien in general is responsible for the ninhydrin reaction?
    What group of amino acids or protien in general is responsible for the ninhydrin reaction?

    • Simonizer1218 says:

      It would be the amine group. In fact, ninhydrin will react with other amines, not necessarily those in proteins or amino acids.

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