Nucleic acids are composed of nucleotides, which contain a nitrogenous base, a pentose sugar, and a phosphate group. There are two main classes of nucleic acids: DNA and RNA. The nucleotides act as building blocks, with the five main nitrogenous bases being adenine, cytosine, guanine, thymine, and uracil. Purines such as adenine and guanine contain two fused rings, while pyrimidines like thymine, cytosine, and uracil contain a single ring. Adenine specifically forms hydrogen bonds with thymine in DNA and uracil in RNA, and is involved in important biomolecules like ATP.
2. Introduction
• Nucleic acids are chemical compounds (naturally occurring) capable
of being broken down into;
1. Phosphoric acid
2. Sugars
3. Organic bases (mixtures ; purines and pyrimidines)
• Nucleic acids are the main information-carrying molecules of the cell
• The two main classes of nucleic acids are deoxyribonucleic acid
(DNA) and ribonucleic acid (RNA)
• Nucleotides are the building blocks of nucleic acids
3. NUCLEOTIDES
• Nucleotides are the basic building blocks of nucleic acids (both DNA
and RNA)
• Structurally , nucleotides have 3 components
1. A nitrogenous base
2. A pentose
3. A phosphate
4. Nitrogenous bases
• Nitrogenous compounds that form an important part of nucleotides
which are the building blocks of nucleic acids (DNA & RNA)
• There are a total of five bases found in the DNA and RNA world,
namely – Adenine (A), Cytosine (C), Guanine (G), Thymine (T) and
Uracil (U).
• The bases are subdivided into purines and pyrimidines
• Purines include adenine and guanine
• Pyrimidines include thymine , cytosine , and uracil
5. Purines
• Purine is a heterocyclic aromatic organic compound that consists of two rings
(pyrimidine and imidazole) fused together. It is water-soluble.
• Purines include adenine and guanine among others (hypoxanthine and xanthine)
• These bases form hydrogen bonds with their complementary pyrimidines , thymine
and cytosine respectively .in RNA , the complement of adenine is uracil instead of
thymine
• Purines are mostly naturally available in meat and meat products and not only
important in DNA and RNA but also significant components in a number of other
important biomolecules, such as ATP, GTP, cyclic AMP, NADH, and coenzyme A.
• Purine (1) itself, has not been found in nature, but it can be produced by organic
synthesis.
• They may also function directly as neurotransmitters, acting upon purinergic
receptors. Adenosine activates adenosine receptors.
6.
7. adenine
• Adenine is a two ringed purine derived
nucleobase that has an amino group
attached to the C6 position.
• In the nucleotide structure it forms a
covalent bond with the ribose/deoxyribose
sugar and hydrogen bond with the
adjacent nucleobase, that is either a
thymine or uracil.
• Other compounds formed by adenine
include vitamin B12, adenosine
triphosphate (ATP), nicotinamide adenine
dinucleotide (NAD) and flavin adenine
dinucleotide (FAD).
• Adenine structure formula is C5H5N5