DNA POLYMERASES OF EUKARYOTES AND PROKARYOTES

The enhanced study of molecules and consecutive action of molecules dealing with the interactions in the living organisms is termed as Molecular Biology. The living beings constitute of chemicals, in this field of study, the interaction of the molecules with each other in performing the functions of is studied.

What is DNA polymerase?

Arthur Kornberg discovered DNA Polymerases in 1956. It is a group of enzymes that help in making copies of DNA templates. Its primary use is in the “DNA Replication” mechanism. The enzymes create new copies of the DNA from the existing ones. The “DNA Polymerase” generates the formation of the Phosphodiester bond that is considered to be the backbone of the DNA molecules. It has been followed that the knowledge has been grasping that the both of the Polymerase falling behind as a part of the strand. 

Prokaryotic DNA polymerase in replications 

The DNA strands unwind itself at the initial stage of replication. The enzyme Helicase opens the DNA forming and the replication forks. This replication procedure goes Bidirectionally. The binding of the DNA is protected by the protein coat in the single-strand binding around the replication fork. The replication enzyme Topoisomerase binds the strands ahead of the replication fork and that is helpful in preventing the Supercoiling. The enzyme Primase synthesises the RNA primers that accurately fulfil the DNA strand. The DNA Polymerases add Nucleotides to the 3’- OH of the primer. The Elongation process continues with the Leading Strand and the Lagging Strands. The enzyme Exonuclease removes the RNA primers. Addition of the dNTPs addition acts as the gap fillers in this process. The DNA Ligase seals the gap between the two DNA’s and it helps in forming the Phosphodiester bonds.

Eukaryotic DNA polymerase in replications 

The Eukaryotic DNA has holds that consist of proteins called Histones to form structures called Nucleosomes. At the primary level of the replication process the DNA is made accessible to the protein. Different origins of replication are present in the Eukaryotic Chromosomes. The binding process takes place with the help of enzymes in this stage that is called Initiating. In the Elongation process that is the second step of replication the enzyme DNA Polymerase adds Nucleotides to 3’ of the new Synthesised Polynucleotide strand. Adenine (A) can pair with Thymine (T) and Cytosine(C) can pair only with Guanine (G). The “DNA Polymerase” cannot initiate any new strand synthesis. It can only add Nucleotide to the 3’ at the end of the existing strand. It is noted that gradually the RNA nucleotides in the primer are removed or replaced with the DNA Nucleotides. In the third stage the DNA Polymerase can synthesise only in the 5’ to 3’ direction. As the fork of replication is Antiparallel therefore the two newly synthesised strands actually grow in the opposite directions. This step is called the Leading and Lagging Strands. In the Termination step there are Multiple Origins of replication and it starts replication simultaneously.

Significance of DNA polymerase

The main function of DNA polymerase is to make copies of the DNA from the existing ones. It also evaluates towards restoring and balancing the DNA. The function of the enzymes is to transmit the Genetic information of the DNA from generation to generation. After the discovery of DNA polymerase it has brought up new ways of understanding the replicating of the DNA.

Applications of DNA polymerase

The underlying characteristic of DNA polymerase is cell replication, apart from that it is comparatively used for balancing the genome integrity while repairing and replicating. The significant features include Processivity, Fidelity, and Substrate Nucleotide selectivity has differences among the enzymes. The DNA Polymerase is used for manipulating the Vitro, including Cloning, Sequencing, Mutagenesis, Labelling and others.

Different types 

Types of DNA polymerase in eukaryotes consist of the 5 types which include the Polymerase γ which is the type of Type a Polymerase and function of it is to do the duplication regarding the mitochondrial DNA. The difference of Polymerase can raise a proper effect on mitochondrial DNA. The next type is the Polymerase α and δ and these are the main polymerase that has been used and applied for the DNA replication. The polymerase actually together works for the unbreakability of the primase enzyme and they play an important role for replication. 

Prokaryotic Cells and Eukaryotic Cells are seen and observed that they are not the same behind there is a proper reason. The contraction of every cell depended on the preventive structure of the adequate amount of reprehensive cells. On the other hand, the Prokaryotic cells cover the smaller exterior area in the comparison of eukaryotes. Prokaryotic Cells are less ordered and arranged than the Eukaryotes cells. On the other hand, the eukaryotic cells act as the major part of the energy production of the body and help in building the construction of the membrane. It has been also seen that a group of antibiotics are seen to be interfered with as Quinolones and that is effective for DNA synthesis. 

Conclusion

Throughout this, we acknowledge the field of Molecular Biology evaluating with Prokaryotic and Eukaryotic DNA polymerase. Therefore, the process of replication of Prokaryotic DNA Polymerase, its consequence and its utilisation.     

Observing the work and function on DNA replication, it is found that the method by which the DNA molecule of parents gets copied has the semi conservatively purpose to yield two kinds of DNA molecules.