Proline P
Proline shares many properties with the aliphatic group.
Proline is formally NOT an amino acid, but an imino acid. Nonetheless, it is called an amino acid. The primary amine on the α carbon of glutamate semialdehyde forms a Schiff base with the aldehyde which is then reduced, yielding proline.
When proline is in a peptide bond, it does not have a hydrogen on the α amino group, so it cannot donate a hydrogen bond to stabilize an α helix or a β sheet. It is often said, inaccurately, that proline cannot exist in an α helix. When proline is found in an α helix, the helix will have a slight bend due to the lack of the hydrogen bond.
Proline is often found at the end of α helix or in turns or loops. Unlike other amino acids which exist almost exclusively in the trans- form in polypeptides, proline can exist in the cis-configuration in peptides. The cis and trans forms are nearly isoenergetic. The cis/transisomerization can play an important role in the folding of proteins and will be discussed more in that context.
Glycine
Glycine is one of the non-essential amino acids and is used to help create muscle tissue and convert glucose into energy. It is also essential to maintaining healthy central nervous and digestive systems, and has recently been shown to provide protection via antioxidants from some types of cancer.
Glycine is used in the body to help construct normal DNA and RNA strands—the genetic material needed for proper cellular function and formation. It helps prevent the breakdown of muscle by boosting the body’s levels of creatine, a compound that helps build muscle mass. High concentrations of glycine are found not only in the muscles, but in the skin and other connective tissues as well. Almost 1/3 of collagen, which keeps the skin and connective tissue firm and flexible, is composed of glycine. (High amounts of Glycine are also found in gelatin, which is a form of denatured collagen). Without glycine the body would not be able to repair damaged tissues; the skin would become slack as it succumbed to UV rays, oxidation, and free radical damage, and wounds would never heal.
Glycine is considered a glucogenic amino acid, which means it helps supply the body with glucose needed for energy. It helps regulate blood sugar levels, and thus glycine supplementation may be useful for treating symptoms characterized by low energy and fatigue, such as hypoglycemia, anemia, and Chronic Fatigue Syndrome (CFS).
Glycine is essential for a healthy, normally functioning digestive system. It helps regulate the synthesis of the bile acid used to digest fats, and is included in many commercial gastric antacid agents.
Glycine is necessary for central nervous system function. Research has shown that this amino acid can help inhibit the neurotransmitters that cause seizure activity, hyperactivity, and manic (bipolar) depression. Glycine can also be converted to another neurotransmitter, serine, as needed, and may be beneficial in the management of schizophrenia. In one study, twenty-two schizophrenic patients, who did not initially respond to traditional treatments, added glycine to their ongoing antipsychotic medication and found that it significantly reduced their symptoms. Glycine intake among the participants ranged from 40 to 90 grams daily (0.8 grams per kilogram of body weight). More research concerning the effects of glycine on schizophrenia is underway. Studies have shown that glycine also helps improve memory retrieval loss in those that suffer from a wide variety of sleep-depriving conditions, including schizophrenia, Parkinson’s disease, Huntington’s disease, jet lag, and overwork.
Results from preliminary studies of glycine as a potential treatment for cancer have been promising, and suggest that it may help prevent the development of cancerous tumors and melanoma. In laboratory mice, dietary glycine prevented tumor growth by inhibiting angiogenisis, the process by which tumors develop their own blood supply. Glycine also seems to play a role in keeping the prostate healthy. In one study, glycine was shown to help reduce the symptoms of prostatic hyperplasia in men.
High-protein foods, such as fish, meat, beans, milk, and cheese, are the best dietary sources of glycine. Glycine is also available in capsule and powder forms, and as part of many combination amino acid supplements. There have been no toxic effects associated with glycine, although some people have reported that taking this supplement causes stomach upset.
Individuals with kidney or liver disease should not consume glycine without consulting their doctor. Taking any one amino acid supplement can cause a disruption of the citric acid or Krebs cycle, and cause a build-up of nitrogen or ammonia in the body, which makes the liver and kidneys work harder to remove waste. Anyone taking antispastic drugs should consult a physician before supplementing with glycine, since it theoretically could increase the effects of these medications.
Glycine is used in the body to help construct normal DNA and RNA strands—the genetic material needed for proper cellular function and formation. It helps prevent the breakdown of muscle by boosting the body’s levels of creatine, a compound that helps build muscle mass. High concentrations of glycine are found not only in the muscles, but in the skin and other connective tissues as well. Almost 1/3 of collagen, which keeps the skin and connective tissue firm and flexible, is composed of glycine. (High amounts of Glycine are also found in gelatin, which is a form of denatured collagen). Without glycine the body would not be able to repair damaged tissues; the skin would become slack as it succumbed to UV rays, oxidation, and free radical damage, and wounds would never heal.
Glycine is considered a glucogenic amino acid, which means it helps supply the body with glucose needed for energy. It helps regulate blood sugar levels, and thus glycine supplementation may be useful for treating symptoms characterized by low energy and fatigue, such as hypoglycemia, anemia, and Chronic Fatigue Syndrome (CFS).
Glycine is essential for a healthy, normally functioning digestive system. It helps regulate the synthesis of the bile acid used to digest fats, and is included in many commercial gastric antacid agents.
Glycine is necessary for central nervous system function. Research has shown that this amino acid can help inhibit the neurotransmitters that cause seizure activity, hyperactivity, and manic (bipolar) depression. Glycine can also be converted to another neurotransmitter, serine, as needed, and may be beneficial in the management of schizophrenia. In one study, twenty-two schizophrenic patients, who did not initially respond to traditional treatments, added glycine to their ongoing antipsychotic medication and found that it significantly reduced their symptoms. Glycine intake among the participants ranged from 40 to 90 grams daily (0.8 grams per kilogram of body weight). More research concerning the effects of glycine on schizophrenia is underway. Studies have shown that glycine also helps improve memory retrieval loss in those that suffer from a wide variety of sleep-depriving conditions, including schizophrenia, Parkinson’s disease, Huntington’s disease, jet lag, and overwork.
Results from preliminary studies of glycine as a potential treatment for cancer have been promising, and suggest that it may help prevent the development of cancerous tumors and melanoma. In laboratory mice, dietary glycine prevented tumor growth by inhibiting angiogenisis, the process by which tumors develop their own blood supply. Glycine also seems to play a role in keeping the prostate healthy. In one study, glycine was shown to help reduce the symptoms of prostatic hyperplasia in men.
High-protein foods, such as fish, meat, beans, milk, and cheese, are the best dietary sources of glycine. Glycine is also available in capsule and powder forms, and as part of many combination amino acid supplements. There have been no toxic effects associated with glycine, although some people have reported that taking this supplement causes stomach upset.
Individuals with kidney or liver disease should not consume glycine without consulting their doctor. Taking any one amino acid supplement can cause a disruption of the citric acid or Krebs cycle, and cause a build-up of nitrogen or ammonia in the body, which makes the liver and kidneys work harder to remove waste. Anyone taking antispastic drugs should consult a physician before supplementing with glycine, since it theoretically could increase the effects of these medications.
Leucine
Leucine, an essential amino acid, is one of the three amino acid with a branched hydrocarbon side chain. It has one additional methylene group in its side chain compared with valine.
Leucine (abbreviated as Leu or L)[2] is a branched-chain α-amino acid with the chemical formula HO2CCH(NH2)CH2CH(CH3)2. Leucine is classified as a hydrophobic amino acid due to its aliphatic isobutyl side chain. It is encoded by six codons (UUA, UUG, CUU, CUC, CUA, and CUG) and is a major component of the subunits in ferritin, astacin and other 'buffer' proteins. Leucine is an essential amino acid, meaning that the human body cannot synthesize it, and it therefore must be ingested.
Info Page: Wikipedia
Lysine
Overview:
Lysine, or L-lysine, is an essential amino acid. That means it is necessary for human health, but the body can't manufacture it. You have to get lysine from food or supplements. Amino acids like lysine are the building blocks of protein. Lysine is important for proper growth, and it plays an essential role in the production of carnitine, a nutrient responsible for converting fatty acids into energy and helping to lower cholesterol. Lysine appears to help the body absorb calcium, and it plays an important role in the formation of collagen, a substance important for bones and connective tissues including skin, tendon, and cartilage.
Most people get enough lysine in their diet, although athletes, vegans who don't eat beans, as well as burn patients may need more. Not enough lysine can cause fatigue, nausea, dizziness, loss of appetite, agitation, bloodshot eyes, slow growth, anemia, and reproductive disorders. For vegans, legumes (beans, peas, and lentils) are the best sources of lysine.
Dietary Sources:
Foods rich in protein are good sources of lysine. That includes meat (specifically red meat, pork, and poultry), cheese (particularly parmesan), certain fish (such as cod and sardines), nuts, eggs, soybeans (particularly tofu, isolated soy protein, and defatted soybean flour), spirulina, and fenugreek seed. Brewer's yeast, beans and other legumes, and dairy products also contain lysine. Many nuts also contain lysine along with arginine (lysine counteracts some of the effects of arginine). So if someone is trying to eat a diet rich in lysine to prevent HSV outbreaks, nuts would be a good choice.
Full text Page: University of Maryland Medical Center
