Join me @ IBOtoolbox for free.
Bonnibelle luo
Member Since: 6/30/2016
performance / stats
Country: United States
Likes Received: 20
Featured Member: 0 times
Associates: 2
Wall Posts: 82
Comments Made: 0
Press Releases: 81
Videos: 0
profile visitor stats
TOTAL: 7193
are we ibo associates?
business links
recent videos
active associates
Kris Karafotas     
Last logged on: 5/25/2019

IBOtoolbox Admin     
Last logged on: 5/9/2019

other ibo platforms
Bonnibelle luo   My Press Releases

A full detailed introduction of Amino acids

Published on 2/27/2019
For additional information  Click Here

Preparation of amino acids


Most of the amino acids that make up the protein are biosynthesized as a carbon chain backbone by an intermediate between the Embden-Meyerhof pathway and the citric acid cycle. The exception is aromatic amino acids, histidine, the former biosynthesis is related to the pentose phosphate intermediate erythrose-4-phosphate, which is synthesized by ATP and phosphoribosyl pyrophosphate. Microorganisms and plants can synthesize all amino acids in the body, and some amino acids in animals cannot be synthesized in the body (essential amino acids). The essential amino acids are generally biosynthesized by a multi-step reaction (6 steps or more), and the enzymes required for the synthesis of non-essential amino acids are about 14 kinds, and the synthesis of essential amino acids requires more. About 60 enzymes are involved. The biosynthesized amino acid is used as a synthetic raw material for proteins, and is also used for the synthesis of alkaloids, lignin, and the like. On the other hand, an amino acid is decomposed in a living body due to formation of a keto acid by amino transfer or oxidation, or is decomposed after being converted into an amine by decarboxylation.


Classification of amino acids

The structural difference between the 20 protein amino acids depends on the difference in the side chain group R. Usually classify 20 amino acids according to the chemical structure or properties of the R group

Polarity according to side chain groups

8 kinds of non-polar amino acids (hydrophobic amino acids)










Polar amino acids (hydrophilic amino acids):

Polarity without charge: 7 species

Glycine (Gly)

Serine (Ser)

Threonine (Thr)

Cysteine ??(Cys)

Tyrosine (Tyr)

Asparagine (Asn)

Glutamine (Gln)


Polar positively charged amino acids (basic amino acids) 3 lysine (Lys) arginine (Arg) histidine (His)


Polar negatively charged amino acids (acidic amino acids) 2 aspartic acid (Asp) glutamic acid (Glu)


Chemical structure classification

Aliphatic amino acids:

C, bright, bright, egg, asparagus, gluten, lysine, refined, sweet, silk, sulphate, cysteine, asparagine, glutamine

Aromatic amino acids: phenylalanine, tyrosine

Heterocyclic amino acids: histidine, tryptophan

Heterocyclic amino acid: proline


Nutrition classification

  1. Essential amino acid: It refers to the fact that the human body (or other vertebrates) cannot be synthesized or synthesized at a rate that is far from being adapted to the body. It must be supplied by food proteins. These amino acids are called essential amino acids. The required amount of essential amino acids in adults is about 20% to 37% of the protein requirement.

There are 8 kinds of roles that are:

Lysine: promotes brain development, is a component of liver and gallbladder, can promote fat metabolism, regulate pineal gland, breast, corpus luteum and ovary to prevent cell degradation;

Tryptophan: promote the production of gastric juice and pancreatic juice;

Phenylalanine: involved in the elimination of kidney and bladder function loss;

Methionine (methionine): participates in the composition of hemoglobin, tissue and serum, and promotes the function of the spleen, pancreas and lymph;

Threonine: a function that shifts certain amino acids to equilibrium;

Isoleucine: involved in the regulation and metabolism of the thymus, spleen and subarachnoid; the subordinate glandular genus acts on the thyroid gland and gonads;

Leucine: the action balance isoleucine;

Proline: acts on the corpus luteum, breast and ovary.

Semi-essential amino acids and conditionally essential amino acids:

Arginine: A complex preparation made of arginine and deoxycholic acid (Minofron) is an effective drug for the treatment of syphilis, viral jaundice and other diseases.

Histidine: It can be used as a biochemical reagent and a medicament, and can also be used for treating diseases such as heart disease, anemia, and rheumatoid arthritis.

Although the human body can synthesize arginine and histidine, it usually cannot meet the normal needs. Therefore, it is also called semi-essential amino acid or conditionally essential amino acid, and these two are essential amino acids in the early growth stage of children. The amount of essential amino acids required by the human body decreases with age, and adults are significantly lower than infants.

Nonnessential amino acid: refers to a person (or other vertebrate) that can synthesize itself from a simple precursor without the need for amino acids obtained from food. For example, amino acids such as glycine and alanine.


Basic reaction detection

  1. Ninhydrin reaction (ninhydrin reaction)

Reagent color note

Ninhydrin (heated by weak acid environment) Purple (proline, hydroxyproline is yellow) (test α-amino)

  1. Sakaguchi reaction (Sakaguchi reaction) α-naphthol + alkaline sodium hypobromite red (Check the thiol arginine for this reaction)
  2. Milon reaction (also known as Mirren reaction)

HgNO3+HNO3+ hot red (test phenolic tyrosine for this reaction, white for unheated)

  1. Folin-Ciocalteau reaction (phenol reagent reaction)

Phosphotungstic acid-phosphoric acid citrate blue (test phenolic tyrosine for this reaction)

  1. Yellow protein reaction

Concentrated nitric acid boiled yellow (test benzene ring tyrosine, phenylalanine, tryptophan has this reaction)

  1. Hopkin-Cole reaction (glyoxylate reaction)

Adding glyoxylic acid and adding it to the concentrated sulfuric acid acetaldehyde and concentrated sulfuric acid at the interface of the surface to produce a purple-red ring (test thiol tryptophan has this reaction)

  1. 7.Ehrlich reaction

P-dimethylaminobenzaldehyde + concentrated hydrochloric acid blue (test thiol tryptophan has this reaction)

  1. Nitrogen salt test

Na2(NO)Fe(CN)2*2H2O+ dilute ammonia red (check the thiol cysteine ??for this reaction)

  1. Sulliwan reaction

1,2 naphthoquinone, sodium 4 sulfonate + Na2SO3 red (test thiol cysteine ??has this reaction)

  1. Folin reaction

1,2 naphthoquinone, sodium 4-sulfonate in alkaline solution dark red (test alpha-amino acid)


Peptide bond: A carboxyl group of one amino acid is condensed with an amino group of another amino acid to remove an amide bond formed by one molecule of water.

Peptide: A polymer formed by covalently linking two or more amino groups through a peptide bond. It is a compound in which an amino acid is linked by a peptide bond, and a product in which the protein is not completely hydrolyzed is also a peptide. Peptides are called dipeptides, tripeptides, tetrapeptides, etc. according to the number of amino acids in which they are composed, and are generally called oligopeptides composed of 10 or less amino acids, and 10 peptides. The above amino acid composition is called a polypeptide, which are simply referred to as peptides. The amino acid in the peptide chain is not a free amino acid molecule because its amino group and carboxyl group are both bound in the formation of a peptide bond, and thus the amino acids in the polypeptide and protein molecules are referred to as amino acid residues.


About us

Lifeasible plant breeding and culture services support increasingly stringent safety and quality standards in the agricultural industry. Relying on our revolutionary techniques, various molecular breeding services and molecular diagnostic methods are offered for a wider range of agriculture-related sectors. Here are some our products: AuxinsCytokininsGelling AgentsSalts Mixture, etc.

Member Note: To comment on this PR, simply click reply on the owners main post below.
-  Copyright 2016 IBOsocial  -            Part of the IBOtoolbox family of sites.