There are 5 known Prokaryotic DNA polymerases:
There are at least 15 Eukaryotic DNA polymerase:
Family B
Polymerases mostly contain replicative polymerases and include the major eukaryotic DNA polymerases α, δ, ε, (see Greek letters) and also DNA polymerase ζ. Family B also includes DNA polymerases encoded by some bacteria and bacteriophages, of which the best-characterized are from T4, Phi29, and RB69 bacteriophages. These enzymes are involved in both leading and lagging strand synthesis during replication. A hallmark of the B family of polymerases is their highly faithful DNA synthesis during replication. While many have an intrinsic 3'-5' proofreading exonuclease activity, eukaryotic DNA polymerases α and ζ are two examples of B family polymerases lacking this proofreading activity.
Family_C">Family CPolymerases are the primary bacterial chromosomal replicative enzymes. DNA Polymerase III alpha subunit from E. coli is the catalytic subunit [1] and possesses no known nuclease activity. A separate subunit, the epsilon subunit, possesses the 3'-5' exonuclease activity used for editing during chromosomal replication. Recent research has classified Family C polymerases as a subcategory of Family X[citation needed]. Family_D">Family DPolymerases are still not very well characterized. All known examples are found in the Euryarchaeota subdomain of Archaea and are thought to be replicative polymerases. Family_X">Family XContains the well-known eukaryotic polymerase pol β, as well as other eukaryotic polymerases such as pol σ, pol λ, pol μ, and terminal deoxynucleotidyl transferase (TdT). Pol β is required for short-patch base excision repair, a DNA repair pathway that is essential for repairing abasic sites. Pol λ and Pol μ are involved in non-homologous end-joining, a mechanism for rejoining DNA double-strand breaks. TdT is expressed only in lymphoid tissue, and adds "n nucleotides" to double-strand breaks formed during V(D)J recombination to promote immunological diversity. The yeast Saccharomyces cerevisiae has only one Pol X polymerase, Pol IV, which is involved in non-homologous end-joining. Family_Y">Family YY Polymerases differ from others in having a low fidelity on undamaged templates and in their ability to replicate through damaged DNA. Members of this family are hence called translesion synthesis (TLS) polymerases. Depending on the lesion, TLS polymerases can bypass the damage in an error-free or error-prone fashion, the latter resulting in elevated mutagenesis. Xeroderma pigmentosum variant (XPV) patients for instance have mutations in the gene encoding Pol η (eta), which is error-free for UV-lesions. In XPV patients, alternative error-prone polymerases, e.g., Pol ζ (zeta) (polymerase ζ is a B Family polymerase a complex of the catalytic subunit REV3L with Rev7, which associates with Rev1[2]), are thought to be involved in mistakes that result in the cancer predisposition of these patients. Other members in humans are Pol ι (iota), Pol κ (kappa), and Rev1 (terminal deoxycytidyl transferase). In E. coli, two TLS polymerases, Pol IV (DINB) and Pol V (UmuD'2C), are known.Family RT
The reverse transcriptase family contains examples from both retroviruses and eukaryotic polymerases. The eukaryotic polymerases are usually restricted to telomerases. These polymerases use an RNA template to synthesize the DNA strand.
Variety across Species:DNA polymerases have highly-conserved structure, which means that their overall catalytic subunits vary, on a whole, very little from species to species. Conserved structures usually indicate important, irreplaceable functions of the cell, the maintenance of which provides evolutionary advantages.Some viruses also encode special DNA polymerases, such as Hepatitis B virus DNA polymerase. These may selectively replicate viral DNA through a variety of mechanisms. Retroviruses encode an unusual DNA polymerase called reverse transcriptase, which is an RNA-dependent DNA polymerase (RdDp). It polymerizes DNA from a template of RNA.
Short Answer: There are almost a dozen different types of DNA polymerase: some may have a subunit that performs the unwinding functions.
DNA Polymerase.
DNA Polymerase is the enzyme which adds new nucleotides during replication.
DNA polymerase is a catalyst, by catalyzing the synthesis of new DNA by adding nucleotides to a preexisting chain. There are several different DNA polymerases, but DNA polymerase I and DNA polymerase II play the major roles in DNA replication.
RNA mRNA tRNA
Short Answer: There are almost a dozen different types of DNA polymerase: some may have a subunit that performs the unwinding functions.
There are different types of DNA polymerase depending if it's from a eukaryotic or prokaryotic cell each performing specific tasks. Basically DNA polymerase catalyzes the formation of a polymer, a DNA strand, from many monomers, deoxyribonucleotides.
There are different types of DNA polymerase depending if it's from a eukaryotic or prokaryotic cell each performing specific tasks. Basically DNA polymerase catalyzes the formation of a polymer, a DNA strand, from many monomers, deoxyribonucleotides.
DNA Polymerase.
DNA Polymerase is the enzyme which adds new nucleotides during replication.
In humans, many enzymes are involved in DNA replication. Among them are: DNA polymerase I DNA polymerase III Ligase Primase Helicase DNA polymerase I and III perform the bulk of the actual reproduction--their job is to add nucleotides to the growing strands. The others perform specialized functions and are essential to the process.
DNA polymerase replicated DNA. RNA polymerase creates mRNA to be used in protein synthesis. RNA polymerase does not replicated DNA.
DNA polymerase matches the bases on the parent strand.
The enzyme that transcribes the DNA into RNA is called RNA polymerase.
DNA Polymerase III
DNA ligase. Apex
dna polymerase