DNA and Guanine
Generally, all complex substances are made up of smaller building blocks, considering an example where our house is built with bricks, stones, woods, etc. and as the same; our body is made up of cells which form the basic unit of live.
Likewise, DNA is also made up of smaller molecules which together functions as the important substance to live in.
We know that DNA is a complex molecule made up many substances like phosphoric acid, sugar (5-carbon) and nucleobases.
There are five nitrogenous bases which serves as the most vital and important component in the functioning of the DNA.
The nuclear bases are mostly of adenine, guanine, thymine and cytosine, and uracil in case of RNA.
These bases are generally classified into two types namely purine and pyrimidine.
History of Guanine?
Guanine was first isolated by Julius Bodo Unger a German chemist in the year 1844. It was first obtained by him in the form of mineral which is extracted from the excreta of sea birds. Which is commonly refers to as guano. It is was then used as a source of fertilizer.
It was later named as guanine in the year 1846. In between the years 1846 and 1906 the scientist named Fischer showed the structure and described the conversion of uric acid into guanine.
What is Guanine?
Guanine is a purine nucleobase. The chemical formula of guanine is C5H5N5O. Where the purines are heterocyclic aromatic compounds which are organic in nature.
As these purine and adenine is composed of two carbon rings namely pyrimidine ring and an imidazole ring.
Guanine can be seen in both DNA and RNA. Its complementary base pair is cytosine which combines with it in a DNA or RNA with the help of three hydrogen bonds.
Guanine is one of the groups of organic compounds which belongs to the group of purines.
It is generally characterized by its two-ring structure which is made up of carbon. And nitrogen atoms and other free occurring or combines diverse group of substances like dead bodies of other lower vertebrates like bats, birds and sealed and sugar beets, yeasts and scales of fish.
It is one oof the component of nucleic acid and one of the vital cellular components in storing and transmitting hereditary characters to the next generation.
It was first discovered by the scientist named Guano in the year 1846 and was first isolated from the nucleic acid in the year 1891.
The other complex molecules that are obtained from nucleic acids include the nucleoside, guanosine and deoxyguanosine where guanine is combined with the sugar molecules like ribose and deoxyribose and it also includes other nucleotides like guanylin acid and other dioxygenyl acid, where the phosphoric acid diester bonds of guanosine and deoxyguanosine.
Nucleotides are the molecules that constitute the fundamental and structural units of nucleic acids.
Nucleotides are the smallest subunits lacking the phosphoric acid.
Characteristic of Guanine
Along with other nucleosides guanine is present in both nucleic acids like DNA and RNA.
Guanine usually have two tautomeric forms, where as the one is commonly present keto group and the other is rarely present enol form.
Guanine always pairs up with cytosine of the amino group which acts a bond donor for hydrogen.
This nucleotide is hydrolyzed with the strong acid like glycine, ammonia, carbon dioxide and carbon monoxide.
First the guanine is deaminated to become xanthin. Guanine then readily oxidizes adenine which is the other purine derivative in the basses of DNA.
Guanine has a melting point of about 350ºC which reflects the intermolecular hydrogen bonding between the amino groups in the molecule of crystal.
Due to its intermolecular bonding of hydrogen between these two oxo and amino groups guanine is relatively insoluble in water but it is soluble in other dilute acids and bases.
Biological Uses of Guanine
The word Guanine was being derived from the Spanish word guano. Guanine has a wide variety of biological functions ranging from its complexity and versatility. Which includes the display, camouflage and vision and also for many other purposes.
Albburns is extracted from the scales of fish and is commonly called as pearl essence and it is generally a crystalline guanine. This crystalline guanine is used in a cosmetic industry for additive purposes in the manufacturing of shampoos which is the main reason for their iridescent pearly effect.
This is also being used in the metallic paints, synthetic pearly and also in plastics.
It is also being used in eye shadows and in nail polishes artificially.
Guanine is also used as substrate in spray paintings and in the lustrous paint materials. Whereas spiders, scorpions and some other amphibians converts the ammonia into guanine by a protein metabolism, which takes place in the cells.
In such case guanine is excreted with the minimum loss of water. Guanine is also found in the specialized skin cells which are found in fishes and in some amphibians namely iridocytes.
It is also being present in the deposits of eyes in the deep-sea fishes and in some reptiles such as crocodiles.