Thermococcus litoralis(Tli) DNA polymerase (TliDNA polymerase; Vent™ DNA polymerase; EC 2.7.7.7)

2005 ◽  
Vol 83 (2) ◽  
pp. 147-165 ◽  
Author(s):  
François Vigneault ◽  
Régen Drouin

An optimized procedure for the ligation-mediated polymerase chain reaction (PCR) technique using Thermococcus litoralis exo– DNA polymerase (Vent exo–) was developed. The optimal dosage of Vent exo– at the primer extension and PCR amplification steps as well as the optimal DNA quantity to use were established. We showed that Vent exo– can efficiently create the blunt-ended termini required for subsequent linker ligation. Vent exo– proves to be more efficient than Pyrococcus furiosus exo– (Pfu exo–) for this task. Vent exo– resolves highly GC-rich sequence substantially better than Thermus aquaticus DNA polymerase (Taq) and with a similar efficiency as Pfu exo–. The DNA/DNA polymerase activity ratio is significantly higher for Vent exo– than for Pfu exo–, which is reflected by the sensibility of Vent exo– in efficiently amplifying genomic DNA. Furthermore, the range of efficiency of Vent exo– demonstrates the importance of conducting evaluative testing to identify the optimal dosage of use of this polymerase to obtain successful PCR amplification. Optimal MgSO4 concentrations to use with Vent exo– were established. Our results show that Vent exo– DNA polymerase produces bands of uniform and strong intensity and can efficiently be used for the analysis of DNA in living cells by ligation-mediated PCR.Key words: Vent exo– DNA polymerase, Pfu exo– DNA polymerase, DNA sequence context, ligation-mediated polymerase chain reaction (PCR), PCR buffer.


1991 ◽  
Vol 19 (18) ◽  
pp. 4967-4973 ◽  
Author(s):  
P. Mattila ◽  
J. Korpela ◽  
T. Tenkanen ◽  
K. Pitkämem

Abstract We demonstrate that the DNA polymerase isolated from Thermococcus litoralis (VentTM DNA polymerase) is the first thermostable DNA polymerase reported having a 3′—5′ proofreading exonuclease activity. This facilitates a highly accurate DNA synthesis in vitro by the polymerase. Mutational frequencies observed in the base substitution fidelity assays were in the range of 30×10−6. These values were 5–10 times lower compared to other thermostable DNA polymerases lacking the proofreading activity. All classes of DNA polymerase errors (transitions, transversions, frameshift mutations) were assayed using the forward mutational assay (1). The mutation frequencies of Thermococcus litoralis DNA polymerase varied between 15−35×10−4 being 2 – 4 times lower than the respective values obtained using enzymes without proofreading activity. We also noticed that the fidelity of the DNA polymerase from Thermococcus litoralis responds to changes in dNTP concentration, units of enzyme used per one reaction and the concentration of MgSO4 relative to the total concentration of dNTPs present in the reaction. The high fidelity DNA synthesis In vitro by Thermococcus litoralis DNA polymerase provides good possibilities for maintaining the genetic information of original target DNA sequences intact in the DNA amplification applications.


1997 ◽  
Vol 324 (2) ◽  
pp. 667-671 ◽  
Author(s):  
Norio OGATA ◽  
Takanori MIURA

DNA polymerase catalyses replication of cellular DNA. The reaction requires a primer–template complex, and a new DNA chain grows from the 3′ end of the primer along the template; no genetic information is created in this reaction. We demonstrate that DNA polymerase from Thermococcus litoralis, a hyperthermophilic marine Archaea, can synthesize up to 50000 bp of linear double-stranded DNA in the complete absence of a primer–template complex, indicating that genetic information is ‘created.’ The possibility of DNA contamination in the reaction mixture, which may serve as a primer and/or template, was vigorously excluded; for example, pretreatment of DNA polymerase with DNase I or extensive chromatographic purification of the substrate, deoxyribonucleoside 5′-triphosphates, did not abolish the primer–template-independent DNA synthesis. The DNA synthesized was (CTAGATAT)n, (TAGATATCTATC)n or a related sequence. Similar repetitive sequences are found in centromeric satellite DNA of many organisms. The significance of this ab initioDNA synthesis is that genetic information can flow from protein to DNA.


2005 ◽  
Vol 41 (1) ◽  
pp. 34-41 ◽  
Author(s):  
G. B. Slobodkina ◽  
N. A. Chernykh ◽  
S. A. Lopatin ◽  
A. V. Il?ina ◽  
G. E. Bannikova ◽  
...  

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