Deoxyribose nucleic acid, DNA

Deoxyribose nucleic acid (DNA) Comprises a backbone with four nucleotide bases, adenine, cytosine, guanine and thymine, bound to it. The genetic information in all cells is encoded in this genome of double-stranded DNA, comprising 3 billion base pairs located in the chromosomes. 

In 1953, James Watson and Francis Crick (Figure 9) suggested a structure for deoxyribose nucleic acid (DNA). The suggestion had important novel features. One was that it had two helical chains, each coiling around the same axis but having opposite direction. The two helices going in opposite direction, and thus complementing each other, is a simple consequence of the twofold symmetry of the whole double... 

Considering its integral importance to life, the structural components of deoxyribose nucleic acid (DNA) are remarkably simple. Each strand of DNA is a linear polymer comprising a constant backbone of alternating deoxyribose sugars and negatively charged phosphodi-esters, and a selection of four heterocyclic bases (Fig. 1). The uniqueness of the DNA strand is defined purely in terms of the sequence of the bases. 

Under such circumstances, it makes little sense to ask which specific positive ions are attributed to DNA as its own counterions — protons H+ or some of the present positive metal ions. This may lead to the question whether DNA and RNA deserve the character A in their abbreviated names, which stands for acid , or, maybe, it is more productive to think of DNA as a salt of the corresponding acid This question seems purely terminological to a physicist, but a chemist may have a different opinion. On this topic we can only cite the very first sentence from the famous very first paper by J. Watson and F. Crick, where they announce their discovery of the double helix We wish to suggest a structure for the salt of deoxyribose nucleic acid (DNA) . 

The sugars are typically ribose (ribonucleic acids, RNA), or 2-deoxyribose (deoxyribonucleic acids, DNA). There are five common bases in nucleic acids adenine (A) thymine (T) uracil (U) cytosine (C) and guanine (G). DNA polymers incorporate the four bases. A, T, C, and G, and RNA, the set A, U, C, and G. 

The nucleic acids DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) are biological polymers that act as chemical carriers of an organism s genetic information. Enzyme-catalyzed hydrolysis of nucleic acids yields nucleotides, the monomer units from which RNA and DNA are constructed. Further enzyme-catalyzed hydrolysis of the nucleotides yields nucleosides plus phosphate. Nucleosides, in turn, consist of a purine or pyrimidine base linked to Cl of an aldopentose sugar—ribose in RNA and 2-deoxyribose in DNA. The nucleotides are joined by phosphate links between the 5 phosphate of one nucleotide and the 3 hydroxyl on the sugar of another nucleotide. 

Those nucleosides found in the nucleic acids DNA and RNA involve the joining of ribose of deoxyribose to a purine or a pyrimidine base. One such nucleoside is adenosine, in which a nitrogen of adenine is linked to carbon 1 of the pentose, ribose. In this form it is a component of RNA but as a phosphory-lated derivative of adenosine (e.g. ATP), which is a high energy compound, it fulfils an important role in metabolism. The dinucleotides NAD and NADP are two cofactors necessary for many enzymic transformations and these also contain /V-glycosides of ribose phosphate. Other important nucleosides are found... 

So far, I have described the primary structure of a nucleic acid. DNA is a linear polynucleotide based on 2 -deoxyribose as sugar and A, Ci C, and T as bases. RNA is a linear polynucleotide based on ribose as sugar and A, G, C, and U as bases. In both... 

Whilst many biochemicals are mono-esters of phosphoric acid, the nucleic acids DNA and RNA (see Section 14.2) provide us with good examples of diesters. A short portion of one strand of a DNA molecule is shown here the most significant difference in RNA is the use of ribose rather than deoxyribose as the sugar unit. 

James D. Watson (1928-) and Francis H. C. Crick (1916- ) publish two landmark papers in the journal Nature. The papers are entitled Molecular structure of nucleic acids a structure for deoxyribose nucleic acid and Genetic implications of the structure of deoxyribonucleic acid. Watson and Crick propose a double helical model for DNA and call attention to the genetic implications of their model. Their model is based, in part, on the x-ray crystallographic work of Rosalind Franklin (1920-1958) and the biochemical work of Erwin Chargaff (1905- ). Their model explains how the genetic material is transmitted. 

Abbreviations DNA, deoxyribose nucleic acid ECD, electrochemical detection LIF, laser induced fluorescence LOD, limit of detection PDMS, poly(dimethylsiloxane) PSA, prostate specific antigen TOF-MS, time-of-flight mass spectrometer TNT, 2,4,6-trinitrotoluene. 

DNA Deoxyribose nucleic acid. It is found in the nuclei of all cells. It carries the necessary hereditary information that enables highly specific proteins to be constructed. 

Nucleic acids—DNA and RNA—are high-molar-mass polymers that carry genetic instructions for protein synthesis in cells. Nucleotides are the building blocks of DNA and RNA. DNA nucleotides each contain a purine or pyrimidine base, a deoxyribose molecule, and a phosphate group. RNA nucleotides are similar but contain different bases and ribose instead of deoxyribose. 

Nucleotides in DNA and RNA. Nucleotides are the monomeric units of the nucleic acids, DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). Each nucleotide consists of a heterocyclic nitrogenous base, a sugar, and phosphate DNA contains the purine bases adenine (A) and guanine (G) and the pyrimidine bases cytosine (C) and thymine (T). RNA contains A, G, and C, but it has uracil (U) instead of thymine. In DNA, the sugar is deoxyribose, whereas in RNA it is ribose. 

How do DNA and RNA differ DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) are the two kinds of nucleic acids. DNA contains the sugar deoxyribose, but RNA has ribose in the same position. The difference in the sugars gives rise to differences in their secondary and tertiary structures. The primary structure of nucleic acids is the order of bases in the polynucleotide sequence, and the secondary structure is the three-dimensional conformation of the backbone. The tertiary structure is specifically the supercoUing of the molecule. 

Watson, James D., and Francis H. C. Crick. Molecular Structure of Nucleic Acids. A Structure for Deoxyribose Nucleic Acid. Nature 171 (1953) 737-78. This is the epochal paper disclosing the double-helix structure of DNA. 

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