Tag Archives: serine

Table of Amino Acid Abbreviations

Students and teachers come together with terms like “Amino acid abbreviations” – but scientists use these abbreviated forms to refer to the 20+ names of amino acids as well.

Amino acids are the building blocks of proteins, and they can be gotten from food. Before we get into the amino acid abbreviations you may want to know that there are two main types of amino acids (with a few exceptions)…

Essential and Non-essential amino acids

Essential amino acids does not mean they are “essential” as in necessary… it simply means that they can only be gotten from the food you eat so must be included through diet or dietary supplementation. Protein foods like meats (beef, chicken, pork, etc.) and eggs, as well as fish, are excellent sources of amino acids. Many meat-eating Americans actually eat an overabundance of protein compared with what the human body requires, which can lead to acidity (which leads to disease), cardiovascular and other diseases.

Non-essential amino acids are those that your body can produce naturally. Occasionally, someone is born with a deficiency in their body’s ability to produce the amino acids necessary for proper functioning, leading to diseases or disorders where people have trouble breaking down certain amino acids. An example of the latter is Maple Syrup Urine Disorder (MSUD) which is what newborn babies are screened for soon after birth.

There are 22 different amino acids in all (some of them semi-essential), but about 20 of them are more common. Their names, 3-letter, and 1-letter amino acid abbreviations follow.

Table of amino acid abbreviations

Amino Acid

3-Letter

1-Letter

Alanine

Ala

A

Arginine

Arg

R

Asparagine

Asn

N

Aspartic acid

Asp

D

Cysteine

Cys

C

Glutamic acid

Glu

E

Glutamine

Gln

Q

Glycine

Gly

G

Histidine

His

H

Isoleucine

Ile

I

Leucine

Leu

L

Lysine

Lys

K

Methionine

Met

M

Phenylalanine

Phe

F

Proline

Pro

P

Serine

Ser

S

Threonine

Thr

T

Tryptophan

Trp

W

Tyrosine

Tyr

Y

Valine

Val

V

Aspartic acid or Asparagine

Asx

B

Any amino acid

Xaa

X

Termination codon

TERM

For more information on amino acid abbreviations or more detailed information on amino acids in general, please see other articles at the Amino Acid Information Center. There are also many excellent resources on the Internet or in encyclopedias.

Reference:

http://www.ncbi.nlm.nih.gov/Class/MLACourse/Modules/MolBioReview/iupac_aa_abbreviations.html

http://en.wikipedia.org/wiki/Amino_acid#In_human_nutrition

http://www.newbornscreening.info/Parents/aminoaciddisorders/MSUD.html

Selenium and Selenocysteine and Health

Selenium is a nonmetal element on the periodic table (between sulfur and tellurium), while Cysteine is a semi-essential amino acid. But when Selenium performs its biological functions, it does so through selenoproteins. Selenoproteins have selenium in them as the form of the 21st amino acid, selenocysteine (also called Sec), which is a cysteine analog. Selenocysteine is encoded by the UGA codon (one of three) in mRNA translation for non-selenoprotein genes. Selenocysteine is a proteinogenic amino acid.

Unlike the 20 regular amino acids (both essential and non-essential) selenocysteine is biosynthesized on its tRNA from the amino acid serine. Interestingly, there are 25 selenoproteins, like selenocysteine and selenomethionine (the latter of which replaces methionine amino acid residues, and is sometimes randomly substituted for methionine), which are encoded in our human genome.

Study on selenium and selenocysteine on health

Selenocysteine, according to S Kurokawa and MJ Berry, in their publication titled Selenium. Role of the essential metalloid in health discuss selenocysteine and its role in health. They say that selenocysteine (Sec) is described as “having stronger nucleophilic and electrophilic properties than cysteine, and Sec is present in the catalytic site of all selenoenzymes. Most selenoproteins, whose functions are known, are involved in redox systems and signaling pathways. However, several selenoproteins are not well characterized in terms of their function.”

Even though selenium can be considered toxic if the dose is too high, it is still required for health purposes in the bigger picture, selenocysteine notwithstanding. According to the researchers the selenium field (which includes the selenoproteins, and selenomethionine, etc.) has “grown dramatically in the last few decades, and research on selenium biology is providing extensive new information regarding its importance for human health.”

Selenocysteine, itself, is a building block of selenoproteins, contains selenium, and is present in several enzymes such as glutathione peroxidases, glycine reductases, methionine-R-sulfoxide reductase B1 (SEPX1), and so on). Glutathione and glycine are standard amino acids.

The biochemist, Theresa Stadtman (married to Earl R. Stadtman) at the National Institutes of Health, discovered selenocysteine.

Reference:

http://www.ncbi.nlm.nih.gov/pubmed/24470102

Glycine Benefits: Glycine for Cancer, Diseases, and Other Health Benefits

Glycine is an amino acid that has amazing implications for human health and nutrition. Through the kidneys and liver, glycine uses inter-organ metabolism where it is synthesized from threonine, serine, hydroxyproline, and choline. Glycine is used by the bodies of both humans and animals.

A study done by W Wang, Z Wu, et al., at the State Key Laboratory of Animal Nutrition in Beijing, China’s Agricultural University, covered some of the glycine pathways and how it is biosynthesized and what it is good for.

Benefits of Glycine

According to the study in Beijing, glycine degrades through three different pathways in the body: through glycine cleavage system (GCS), serine hydroxymethyltransferase, and also conversion. Also, “glycine is utilized for the biosynthesis of glutathione, heme, creatine, nucleic acids, and uric acid.”

What many don’t know is that glycine is an important part of bile acids from the liver, which are secreted into the small intestine for the breakdown of fats in digestion. The glycine then, via the bile acids, also help absorb long-chain fatty acids.

According to those who did the study, glycine “plays an important role in metabolic regulation, anti-oxidative reactions, and neurological function.

Thus, this nutrient has been used to:

(1) prevent tissue injury
(2) enhance anti-oxidative capacity
(3) promote protein synthesis and wound healing
(4) improve immunity, and
(5) treat metabolic disorders in obesity, diabetes, cardiovascular disease, ischemia-reperfusion injuries, cancers, and various inflammatory diseases.”

Glycine Benefits Reviewed

The uses for glycine in the body are unreal! Glycine is obviously beneficial to human health, and it is seriously a functional amino acid.

Reference:

http://www.ncbi.nlm.nih.gov/pubmed/23615880