Deoxynucleoside triphosphates, or dNTPs, are the building blocks of DNA. These molecules provide the energy necessary to attach to the next molecule in the DNA strand.
DNA stands for deoxyribonucleic acid, and it is a long chain of nucleotides. Nucleotides are made up of a base, which is either thymine (T), cytosine (C), adenine (A), or guanine (G) and a sugar-like molecule called deoxyribose.
The phosphate groups on the nucleotide bases are what connect to each other, forming the long chain. The different shapes of nucleotide bases allow for different shapes of DNA chains.
There are some viruses that use RNA as their genetic material instead of DNA. Because of this, there are ntpdns that are used to disrupt the production of RNA instead of DNA in infected cells.
Phosphate bond step
A phosphate bond is the last step in the synthesis of a deoxynucleoside triphosphate (dntp) molecule. The deoxynucleoside triphosphate molecule does not provide the energy for DNA synthesis; rather, it is the last link in the chain of reactions that leads to the formation of a new DNA strand.
Phosphate bonds are what connect one DNA strand to another, creating two double-stranded DNA molecules. These bonds are formed when one ATP molecule donates an oxygen and hydrogen atom to one deoxyribose sugar molecule.
When this happens, one phosphate bond is formed, connecting two different DNA molecules together. By doing this, you now have two separate DNA molecules with one common link: a phosphate bond.
Nitrogen-base bond step
A deoxynucleoside triphosphate (dNTP) molecule contains a nitrogen-based base, a pentose sugar, and five phosphate groups. The nitrogen-based base attaches to the sugar via a nitrogen-carbon bond linkage.
These bonds are broken and then reapplied to the DNA backbone in DNA synthesis. The energy required to break these bonds comes from an enzyme called a nucleotidase.
There are many different types of nucleotidases, each one breaking down a specific chemical structure found in the dNTP molecules. These enzymes are particularly important in the process of RNA synthesis due to the higher concentration of these chemicals compared to DNA.
Enzymes that are known as deoxynucleotidase remove oxygen and/or hydrogen atoms from these molecules, producing deoxyribonucleoside monophosphates.
Energy change steps
A deoxynucleoside triphosphate (dNTP) molecule provides the energy for DNA synthesis via a series of steps called energy change steps.
The first energy change step occurs when a dNTP molecule dissociates into NTP and diphosphate molecules. This process requires an amount of high-energy ATP, which is provided by the cell.
The second energy change step occurs when NTP molecules associate with deoxyribonucleotides to form nucleotide pyrophosphates. This process requires an amount of high-energy NAD+, which is provided by the cell.
The third energy change step occurs when nucleotide pyrophosphates undergo hydrolysis, which is the breaking down of a compound through water. This process requires an amount of high-energy water, which is provided by the cell.
What is the role of adenine?
Adenine is part of the deoxyribose sugar molecule. Adenine and another nucleotide, thymine, pair together to form a double-stranded DNA molecule.
Adenine plays an important role in the synthesis of DNA. It provides the energy required to attach it to the next nucleotide, cytosine, on the growing DNA chain.
The adenine and cytosine form a chemical bond called a glycosidic bond. This bond holds the two nucleotides together and forms the backbone of the DNA molecule.
Adenine plays an integral part in DNA synthesis because it provides the chemical energy required to attach the next nucleotide on the chain. Without it, there would be no growth of the new DNA molecule.
What is the role of thymine?
Thymine is one of the five natural nucleobases that are part of DNA. The other nucleobases are cytosine, guanine, adenine, and uracil. Thymine is unique in that it has a hydrogen atom attached to its 5 position nitrogen atom.
This molecule plays an important role in DNA synthesis. When a thymine molecule is attached to RNA rather than DNA, it acts as a trigger for the next step in gene expression: protein production.
During the process of transcription, or copying RNA into new RNA, this thymine molecule is removed. This process is done by a special enzyme called thymidylate synthase. It uses sulfur compounds to remove the thymine molecule from the new RNA strand.
What is the role of guanine?
Guanine is one of the four nucleobases that make up a DNA molecule. Along with cytosine, thymine, and adenine, guanine is a component of the sugar-phosphate backbone of DNA.
Within the guanine nucleobase is where the energy required for DNA synthesis comes from. When a deoxynucleotide triphosphate (dNTP) molecule containing 5-methyl-guanine (mG) bonds with dUMP to form Guanidine DiPhosphate (GDP), the compound loses one phosphate group and breaks down into pyrophosphate and nicotinamide adenine dinucleotide (NAD).
This breakdown of GDP results in the release of energy that is used in the next step of DNA synthesis. When there are no more NAD molecules left to convert into NADH, then more must be synthesized from niacin via circulation in the blood.
What is the role of cytosine?
Cytosine is one of the four nucleobases found in the DNA backbone. The other nucleobases are thymine, uracil, and adenine. Cytosine is usually paired with guanine, but can be paired with uracil or adenine as well.
Cytosine plays an important role in the process of DNA synthesis. Along with guanine, cytosine forms a repeating pattern along the DNA backbone called a strand.
When a cell needs to make new DNA, enzymes bind to cytosine and Guanine molecules and convert them into a new molecule called 5-methylcytosine and 5-hydroxymethylcytosine, respectively.
These molecules are then used to build new DNA strands during replication.
Why are dntps made of different nucleotides?
Different dntps contain different nucleotides, which is why there are many different dntps. This is necessary because DNA requires a specific sequence of nucleotides, and these molecules are the building blocks for DNA.
The first three dntps produced in the DNA synthesis process are dATP, dGTP, and dCTP. These DnTPs all contain adenine as the base molecule, and thymine, guanine, and cytosine as the ring molecule.
These molecules all have different sizes, so they can fit into the DNA strand in different spots. By having molecules of different sizes within a solution containing DNA polymerase II enzyme, more DNA can be made.