Nucleotides are molecules which form a critical part of RNA and DNA, making them important for every living organism on Earth. These special molecules are also involved in enzyme reactions in the body, production of chemical energy, and cell signaling. A number of researchers work with nucleotides, identifying different types and their functions, and studying their chemical structure.
Three separate molecules come together to make a nucleotide. The first is a base which can be a purine or a pyrimidine compound. The base attaches to a pentose sugar, a sugar which has five carbon atoms, to create a nucleoside. The nucleoside in turn joins with a phosphate group, creating a nucleotide. In the case of RNA, the sugar is a ribose sugar, creating a ribonucleotide, and in DNA, the sugar is a deoxyribose sugar, creating a deoxyribonucleotide.
When nucleotides link together, they form nucleic acid, a polymer. In DNA and RNA, chemical bonds create long chains of nucleic acids which are joined in a famous ladder-like shape. The chemical structure of each nucleotide determines which nucleotide it can bond to across the ladder, an important trait which determines how DNA and RNA can be assembled. Each set of nucleotides which makes up a rung in the ladder is known as a base pair, and an individual organism can have billions of base pairs in its genetic code.
Nucleotides, along with amino acids, are sometimes referred to as the building blocks of life, because they provide the basis of the genetic code. In the form of DNA, nucleic acids are capable of undergoing a process known as transcription to create an RNA copy, and the RNA copy directs the production of various proteins by the body. These proteins are involved in daily biochemical processes, and also in the underlying structure of an organism, with genes to produce proteins activating as soon as an egg becomes fertilized and cells start dividing.
Research on nucleotides is concerned with identifying the various nucleotides present in the body and what they do, and in looking at variations in nucleotides which can be linked with pathologies and various natural phenomena. For example, errors in the production of nucleotides can lead to genetic mutations, caused by interference in the copying of DNA which results in damage to various areas of the genetic code. Many researchers use sophisticated computer modeling systems to make models of the nucleotides they work with.