![]() The sugar and phosphate groups found in DNA’s backbone aid in the formation of the helical structure of the molecule. Thymine (T), Adenine (A), Guanine (G), and Cytosine (C) (C). Molecular structure of DNA is a double-stranded helical helix in the form of twisted ladders coiled around one another.ĭNA is composed of four major types of nitrogenous bases: thymine (T), adenine (A), guanine (G), and cytosine (C). Its structural components are nitrogenous bases, sugar molecules, and phosphate groups, and it serves as the building block of all genetic material. Histone proteins are important in maintaining the shape of DNA within the nucleosome. In humans, it is roughly 2.2 m long and is found in a highly coiled condition within the nucleus, which is referred to as a nucleosome. DNA is responsible for the transmission of genetic information and, in addition, it is responsible for the production of protein molecules, which are found in the nucleus of every creature. In biology, DNA stands for Deoxyribonucleic acid, which is a genetic substance present only in prokaryotic and eukaryotic species and is unique to them.Įach nucleotide in DNA is responsible for passing on a person’s personality traits to their progeny from one generation to the next. DNAĭuring the research into the composition of white blood cells in 1869, a Swiss researcher named Johannes Friedrich Miescher discovered the genetic material DNA. Phosphate groups are found in DNA structure and are composed of one negatively charged oxygen atom, which is liable for the negatively charged nature of the complete strand of DNA structure. The phosphate backbone of DNA has a negative charge as a result of the presence of hydrogen bonds formed between both the phosphorus and oxygen atoms in the molecule. Because of the presence of phosphate groups in nucleotides, DNA has a negatively charged charge. This assists in the transfer of qualities from one generation to the next. DNA ligase is able to form a phosphodiester bond between the nucleotides.The existence of genetic material such as DNA or RNA in every organism results in certain parallels in their personalities with their parents. The relative ease of RNA hydrolysis is an effect of the presence of the 2' hydroxyl group.Ī phosphodiesterase is an enzyme that catalyzes the hydrolysis of phosphodiester bonds, for instance a bond in a molecule of cyclic AMP or cyclic GMP.Īn enzyme that plays an important role in the repair of oxidative DNA damage is the 3'-phosphodiesterase.ĭuring the replication of DNA, there is a hole between the phosphates in the backbone left by DNA polymerase I. The phosphodiester linkage between two ribonucleotides can be broken by alkaline hydrolysis, whereas the linkage between two deoxyribonucleotides is more stable under these conditions. Hydrolysis of phosphodiester bonds is catalyzed by phosphodiesterases, which are involved in repairing DNA sequences. In order for the phosphodiester bond to be formed and the nucleotides to be joined, the tri-phosphate or di-phosphate forms of the nucleotide building blocks are broken apart to give off energy required to drive the enzyme-catalyzed reaction. The negative charge attracts histones, metal cations such as magnesium, and polyamines. Repulsion between these negative charges influences the conformation of the polynucleic acids. Phosphodiesters are negatively charged at pH 7. These saccharide groups are derived from deoxyribose in DNA and ribose in RNA. Specifically, the phosphodiester bond links the 3' carbon atom of one sugar molecule and the 5' carbon atom of another (hence the name, 3', 5' phosphodiester linkage ). The 3' carbon of one sugar is bonded to the 5' phosphate of the adjacent sugar. The phosphate is attached to the 5' carbon. Phosphodiester bonds make up the backbones of DNA and RNA. Discussion of phosphodiesters is dominated by their prevalence in DNA and RNA, but phosphodiesters occur in other biomolecules, e.g. The "bond" involves this linkage C−O−PO − 2O−C. In chemistry, a phosphodiester bond occurs when exactly two of the hydroxyl groups ( −OH) in phosphoric acid react with hydroxyl groups on other molecules to form two ester bonds. The 5' end has a 5' carbon attached to a phosphate, and the other end, the 3' end, has a 3' carbon attached to a hydroxyl group. Diagram of phosphodiester bonds ( PO 3− 4) between three nucleotides. ![]()
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