Glycine Structure: Uses, Preparation, Solved Examples

Glycine is the simplest amino acid that occurs in nature. An amino acid is the building block of a protein. They are molecules that combine together to form protein molecules in the body. These amino acids are leftover when proteins are digested or broken down. Our body uses amino acids to prepare proteins that help the body further in breaking down food. Glycine is the only amino acid that is not a stereoisomer. The structures of amino acids contain an -COOH and an - NH₂ group and are, therefore, zwitter-ionic.

Key Takeaways: Glycine structure, glycine properties, amino acids, zwitter-ionic nature of glycine, glycine uses

---

Glycine Structure

[Click Here for Sample Questions]

Glycine is the simplest amino acid that occurs naturally. It is the only achiral amino acid and hence is not stereoisomeric. It can fit into hydrophilic or hydrophobic environments since it has only one hydrogen atom in its smaller side chain. Amino acids have a general structure that has an -R group where specific substituents are replaced to form a particular amino acid. There are 20 amino acids present in the human body. The simplest among all of them is glycine. It has the molecular formula C₂H₅NO₂. The -R group in the general amino acid formula is substituted by a hydrogen atom in glycine. 

Structure of General amino acid

Structure of glycine

where R=H of an amino acid

Zwitter-ionic structure of glycine

Read more:

---

Formation of Glycine

[Click Here for Sample Questions]

Glycine can be formed using two synthetic processes. The two main processes are the following-

i) Amination of chloroacetic acid with ammonia, which gives the products glycine and ammonium chloride.

ii) The Strecker amino acid synthesis, which is the main synthetic method for the preparation of glycine. In this process, an aldehyde is treated with ammonia in the presence of potassium cyanide. The condensation reaction yields alpha-amino nitrile which on further hydrolysis gives the required amino acid, glycine in this case.

R=H, for glycine preparation

iii) Glycine is also a by product or an impurity in the synthesis of EDTA.

Read more:

---

Properties of Glycine

[Click Here for Sample Questions]

Glycine is a sweet-tasting amino acid that has some unusual properties. The properties of glycine are as follows-

1. Glycine is a non-polar, non-essential amino acid.
2. Glycine is a colourless crystalline solid.
3. In an aqueous solution or at a pH nearly neutral, glycine is zwitterionic in nature.
4. Glycine is hydrophilic in nature which is mostly due to the presence of one hydrogen atom.
5. Glycine is highly soluble in water.
6. Due to the acidic nature of glycine, at pH=6, glycine behaves as a buffer solution.
7. It is one of the non-essential amino acids present in mammals.

Read more:

---

Uses of Glycine

[Click Here for Sample Questions]

Glycine is synthesized in the human liver and is very useful in various fields. The uses of glycine are as follows-

1. Glycine aids in the formation of protein in the human body.
2. When glycine is mixed with carbohydrates, the recovery rate becomes faster and provides lean growth.
3. Glycine is used as a sweetener or as a taste enhancer in several food supplements and protein drinks.
4. It helps in treating schizophrenia, stroke, and other metabolic disorders.
5. Glycine acts as a buffer in cosmetics, antacids, toiletries, antacids, etc.
6. Glycine is used in formulating certain drugs that improve gastric absorption.

Read more:

---

Things to Remember 

• Glycine was first isolated in the year 1820 from a substance known as gelatin. Later, a French chemist and pharmacist named Henri Braconnot discovered it glycine by boiling the gelatinous material with sulphuric acid.
• An amino acid is the building block of a protein. They are molecules that combine together to form protein molecules in the body. These amino acids are leftover when proteins are digested or broken down.
• Glycine is formed by the reaction of chloroacetic acid and ammonia, which gives the products glycine and ammonium chloride.
• When glycine is mixed with carbohydrates, the recovery rate becomes faster and provides lean growth.
• Glycine can also be formed using aldehyde and ammonia in presence of potassium cyanide which on hydrolysis gives glycine. This method is known as the Strecker amino acid synthesis.
• Glycine has the molecular formula C₂H₅NO₂ and its structure is-

Read more :