Glycine Structure, Characteristics: 21 Complete Quick Facts

Glycine structure is one of the 20 amino acids found in the human body which are produced naturally. They are of great significance as the human body produces them naturally. Its complete description ranging from structural to physical properties is explained in this article.

Glycine structure is an organic molecule with the formula C2H5NO2. As it is an organic molecule so there is sharing of electrons and formation of covalent bonds. Like any other alpha-amino acid, it has a central carbon atom with an amine (-NH2) group and a carboxyl group attached to it. There is also a carbon chain with it. 

Glycine structure
Glycine structure

Discussing more Glycine structure, then it is one of the essential amino acids which are the building blocks of the proteins which in turn make up the human body. The sequencing of these amino acids including the Glycine structure is further responsible for the formation of our genetic system DNA (deoxyribonucleic acid). Glycine structure is one of the simplest structures which exhibits achiral behavior. Here the central carbon atom has only 2 hydrogen atoms attached to it.

Glycine structure has significance in from chemistry to biochemistry. Discussing its chemical aspect then it is a white powder-like crystalline organic compound that has acid-base properties. As it is a structure with the presence of both acid and base components so it is considered amphoteric. But differences in the pH can change the properties of the glycine structure. Below pH 2.4 glycine structure converts to glycinium and above pH 9.6 to glycinate.

Glycine structure being a multidisciplinary organic compound has many functions to play. Chemically it has usage in coordination chemistry as a bidentate ligand and in ester formation. Glycine structure also exhibits physiological functions where it is a precursor of proteins and acts as a biosynthetic intermediate or neurotransmitter. Apart from this, it has usages in animal feedstock and laboratory research as well.

There are many properties associated with glycine structure, especially its lewis dot structure which gives a detailed description of its electronic, physical, and chemical properties. Some of those characteristics are explained below in detail:

  1. What is Glycine structure?
  2. How to draw Glycine structure?
  3. Glycine structure resonance
  4. Glycine structure shape
  5. Glycine structure formal charge
  6. Glycine structure angle
  7. Glycine structure octet rule
  8. Glycine structure lone pairs
  9. Glycine structure valence electrons
  10. Glycine structure hybridization
  11. Glycine structure solubility
  12. Is Glycine structure soluble in water?
  13. Is Glycine structure a strong electrolyte?
  14. Is Glycine structure acidic or basic?
  15. Is Glycine structure polar or nonpolar?
  16. Is Glycine structure a lewis acid or lewis base?
  17. Is Glycine structure linear?
  18. Is Glycine structure paramagnetic or diamagnetic?
  19. Is Glycine structure an amino acid?
  20. Is Glycine structure an essential amino acid?
  21. Is Glycine structure hydrophobic?

What is Glycine structure?

Glycine structure as mentioned several times above is the simplest form of amino acid found in the human body and is the building block of proteins. Glycine structure is one of the alpha-amino acids where the central carbon is attached to an amino group, a carboxylic acid group, and a hydrogen atom as an R chain.

Due to its simplicity in the R chain as the attachment of only one hydrogen atom, the Glycine structure has high rotational freedom. Due to this flexibility, it has a significant role in protein folding and is put under the category of secondary structure where it forms an alpha helix. 

Glycine structure, unlike other amino acid structures, does not have different atoms attached to the central carbon atom. Hence Glycine structure is achiral and does not form enantiomeric structures.

How to draw Glycine structure?

Glycine structure can be drawn using the lewis dot structure concept which comprises certain steps as explained below:

glycine lewis str
Glycine structure lewis dot representation

Step 1: Calculate the number of valence electrons in the Glycine structure

Glycine structure formula involves the central alpha carbon, amino group (NH2), carboxylic group (COOH), and hydrogen atoms as the side chain. The basic elements involved are carbon, hydrogen, oxygen, and nitrogen with 4, 1, 6, and 5 valence electrons respectively. So the total number of valence electrons is 2×4+5×1+6×2+5= 30.

Step 2: Looking out for the central atom

Glycine structure is an alpha-amino acid. This means there is a central atom that is surrounded by the acidic and basic functional groups. Over here there are 5 main elements present in the Glycine structure, out of which the least electronegative one will be the central atom.

Oxygen is the most electronegative element followed by nitrogen, carbon, and hydrogen. Then accordingly hydrogen should be the central atom. But that is not a possibility because of its small size. Hence in the Glycine structure, the alpha carbon will be the central atom.

Step 3: Bonding between the atoms

Glycine structure is an organic molecule so here there will be sharing of electrons according to the octet rule and the formation of covalent bonds. To gain octet stability the central alpha carbon will share its four electrons with other functional groups.

On one side it will be surrounded by the NH2 functional group and COOH functional group. On the other side, it will be surrounded by two hydrogen atoms. This will satisfy the octet criteria. Also, there is the presence of single covalent bonds. The only double covalent bond is found in the -COOH group.

Step 4: Calculating the formal charge

Calculating formal charge is a very important criterion for the authenticity and existence of the Glycine structure. The lesser the formal charge of glycine structure the more the stability. Over here the formal charge of Glycine structure is 0 which confirms its reliability and existence.

Glycine structure resonance

Glycine structure being an organic molecule with lone pair of electrons and a double bond can undergo delocalization and form resonance or canonical structures. The movement of electrons can lead to the formation of a different structure with completely different acidic and basic properties known as a zwitterion.

The zwitterion of glycine structure leads to change in the functional groups where NH2 forms NH3+ and COOH forms COO-. They can be best understood diagrammatically.

glycine resonance
Resonance in Glycine structure (Zwitterion formation)

Glycine structure shape

Glycine structure is the simplest amino acid and has a lot of conformers but its geometry and shape are something which is still undergoing extensive research theoretically and practically. The microwave and ab initio studies have shown that a single conformer as shown in the diagram is the correct and most stable shape of Glycine structure with much more flexibility in its rotational constant.

The ball and stick model of the Glycine structure represents the atoms and covalent bonds but does not show the true size and shape of the molecule.

The stick model only shows the bonds and the peptide backbone of the Glycine structure. The space-filling models show only the radii and the shape associated with them but hide the actual size and structure.

Another factor based on which shape is decided is the atoms involved. In Glycine structure around N and CH2 the geometry is tetrahedral and around CO2- the geometry is trigonal planar.

glycine 3D
3D representation of Glycine structure

Glycine structure formal charge

The formal charge of Glycine structure like any other molecule can be calculated using the formula 

FC = V-N-B/2

FC of carbon in Glycine structure = 0

FC of oxygen in Glycine structure = 0

FC of nitrogen in Glycine structure = 0

FC of hydrogen in Glycine structure = 0 

Glycine structure angle

Glycine structure is a protein molecule and finding its angle is a complex job which usually happens using a fundamental tool named Ramachandra plot. It involves quantum chemistry and modern atomic terminologies like psi and phi where the angles are decided according to it. When it comes to Glycine structure the psi angles are at 180 degrees and 0 degrees.

It is according to one conformer where the oxygen and nitrogen are sandwiched between 2 alpha hydrogens. The rest of the topic on Glycine structure angle is very complex and based on quantum calculations which are out of the scope of this article.

Glycine structure octet rule

The octet rule is one of the most important roles when it comes to establishing the stability of compounds. It is a set of criteria followed by most of the compounds except for some anomalies to achieve stability and Glycine structure is not untouched. It also follows the octet rule as explained by its lewis dot structure.

It is very much clear that carbon, oxygen, nitrogen, and hydrogen have 4, 6, 5, and 1 valence electrons respectively. To achieve stability they need 4, 2, 3, and 1 valence electrons which happen by sharing of electrons where NH2 and COOH octet stable functionalities are involved along with the 2 hydrogen atoms side chain all attached to an alpha carbon atom through single covalent bonds.

Glycine structure lone pairs

Glycine structure is the simplest structure with a single hydrogen atom as its side chain. It is an organic molecule that follows the octet rule in its bonding and certainly, it does have electrons that have not participated in its bonding and are termed as lone pairs of Glycine structure. Discussing its alpha carbon atom which is surrounded by amine and carboxylic acid functionalities does not have a lone pair of electrons.

The lone pair of electrons is found on the functional groups attached to the alpha carbon atom. The amino group NH2 has 1 lone pair of electrons on the nitrogen atom. The COOH group has lone pairs of electrons on both the oxygen atoms.

The oxygen atom involved in double covalent bond and single covalent bond formations has 2 lone pairs of electrons each. So in the Glycine structure, there are a total of 5 lone pairs of electrons.

Glycine structure valence electrons

Valence electrons in the Glycine structure can be counted individually for an atom. We know that in Glycine there are 2 carbon atoms, 2 oxygen atoms, 1 nitrogen atom, and 5 hydrogen atoms. After the bonding, all of these elements in the Glycine structure have 8 valence electrons according to the octet stability criteria.

But before bonding, the Glycine structure comprises 2 carbon atoms with 4 electrons each, 2 oxygen atoms with 6 electrons each, 1 nitrogen atom with 5 electrons, and 5 hydrogen atoms with 5 electrons each. Hence the total number of valence electrons is 30.

Glycine structure hybridization

The hybridization of the Glycine structure depends on the individual atoms and functionalities involved in the structure. Over here there are three hybridization types associated with Glycine structure. These hybridizations are as follows:

The nitrogen atom is sp3 hybridized.  The CH2 group in glycine structure is also sp3 hybridized and finally the carboxylate functionality CO2- is sp2 hybridized. 

Glycine structure solubility

Glycine structure is one of the important and simplest alpha-amino acids. Its solubility in different mixtures is still in the research arena as published in many academic journals. Different components show different solubility measurements in the Glycine structure.

Glycine structure is soluble in water but with precise measurements. In terms of organic solvents then Glycine structure is soluble in pyridine and sparingly soluble in ethanol. It is insoluble in ether.

Is Glycine structure soluble in water?

Glycine structure is soluble in water but its solubility does not remain at all levels. There is a linear variation of solubility with that of temperature. After several analyses and statistical methods, it was confirmed in research publications and various other journals that Glycine structure solubility is 3.318 mol/kg at 298.15 K.

Is Glycine structure a strong electrolyte?

No, Glycine structure is not a strong electrolyte. Strong electrolytes are those which can completely dissociate or ionize in the solution. Also, strong electrolytes are good conductors of electricity. Glycine structure is an amino acid that is not categorized into acids and bases. Hence its dissociation, especially complete dissociation is not possible. So it is not a strong electrolyte.

Is Glycine structure acidic or basic?

Glycine structure is the simplest amino acid and shows typical acid-base behavior. It is neither a strong acid nor a strong base and shows different equilibrium stages in an aqueous solution according to the pH change.

The cation conjugate of Glycine structure is dominant at low pH and anion conjugate is formed at high pH. The neutral Glycine structure is in equilibrium with the dipolar Glycine structure where the equilibrium favor is in the dipolar one. This is because the H3N+ stabilizes the CO2- and vice versa.

Another noteworthy thing is that between pH 3 and 8, almost every form of Glycine structure is in dipolar form and at the center of this range when the concentration of acid conjugate is equal to basic conjugate is called the isoelectric point.

Is Glycine structure polar or nonpolar?

The polarity of Glycine structure as compared to other amino acids is very complex. It is considered a non-polar amino acid but a polar molecule. The reason behind this unusual behavior is because of the absence of a side R chain.  From a chemistry point of view, it is a polar molecule because of the presence of electronegative oxygen and nitrogen atoms against the hydrogen atom. 

From a biochemistry point of view, it is a nonpolar molecule because there the side chains are considered. Since in Glycine structure the side chain is hydrogen so the dipole moment is 0. Hence Glycine structure though polar is considered nonpolar in protein structures.

Is Glycine structure a lewis acid or lewis base?

Glycine structure cannot be categorized as lewis acid or base like many other compounds. It is an amino acid and exists in the form of zwitterion at neutral pH. So at different pH values, it exists as lewis acid or lewis base.

Is Glycine structure linear?

No, Glycine structure is not linear. It is a symmetrical amino acid and exists as a secondary structure instead of a linear structure in the form of alpha-helix due to its flexible rotational constant.

Is Glycine structure paramagnetic or diamagnetic?

The magnetic nature of the Glycine structure alone cannot be predicted. To confirm whether it is paramagnetic or diamagnetic is only possible when it acts as a ligand and forms a complex with transition metal ions or the lanthanides and actinides.

Glycine structure interaction with the metals decides whether the unpaired electrons are present or not thereby confirming the paramagnetic or diamagnetic behavior.

Is Glycine structure an amino acid?

Glycine structure is an amino acid that has a single hydrogen atom attached to it as a side chain. Glycine structure is also designated as proteinogenic amino acids where it is encoded by codons starting with GG.

It is helpful in the formation of alpha-helices in secondary structures which are an important compact form. Due to the Glycine structure, this property is the most abundant amino acid in collagen.

Is Glycine structure an essential amino acid?

Glycine structure is a non-essential amino acid which implies that it is produced naturally in the human body and does not need to be added as a dietary requirement. But nowadays it is used as a dietary supplement with necessary dosages.

Its primary function is the synthesis of proteins which are further essential for the development and building of the skeleton, muscles, and tissues. It is also used for improving sleep quality in case of fatigue and insomnia. It also has a significant impact on the brain and neural health but in the right amount of dosages.

Is Glycine structure hydrophobic?

Glycine structure is a hydrophobic amino acid. It is because of its structure. It is very much evident that in protein formation it is considered non-polar due to the absence of the side R chain.

As Glycine structure is symmetrical and achiral due to this factor it is hydrophobic. Due to the absence of a polar chain Glycine structure cannot interact with water and is hence considered hydrophobic.


In nutshell Glycine structure is an important non-essential amino acid which is simplest in the structure due to absence of a side R chain. It is considered non-essential as it can be produced by human body without any dietary requirements or dosages. Its physical, chemical, structural and electronic properties are affected due to the simple side chain which just consist of hydrogen atoms.

Read more about following Structure & Characteristics

Peptide Bond
Hyaluronic Acid
Disulfide Bond
Alanine Amino Acid
Glycolic Acid
Glutamic Acid
Hexanoic Acid