Purification and properties of Thermus filiformis DNA polymerase expressed in Escherichia coli.

Choi JJ, Jung SE, Kim HK, Kwon ST
Biotechnol Appl Biochem (1999), Volume 30 ( Pt 1), Page 19
PubMed entry


The gene encoding Thermus filiformis (Tfi) DNA polymerase was ...
The gene encoding Thermus filiformis (Tfi) DNA polymerase was expressed under the control of the tac promoter on a high-copy plasmid, pJR, in Escherichia coli. The Tfi DNA polymerase was purified by using heat treatment and DEAE-Sephacel column chromatography. The purified enzyme had a molecular mass of 92 kDa, as estimated by SDS/PAGE. The optimum pH and temperature of the enzyme were 8.4-9.0 and 70-72.5 degrees C respectively. The half-life of the enzyme at 94 degrees C was approx. 40 min. The enzyme was activated by the bivalent cations, Mg(2+) and Mn(2+), and was inhibited by EDTA. The optimal Mg(2+) concentration of the enzyme was 4 mM. The optimal conditions for the PCR reaction were slightly different from those for the enzyme activity except for the optimal Mg(2+) concentration. Low concentrations of KCl had no effect on either the enzymic activity or the PCR amplification. The result of the PCR experiment with the enzyme indicates that Tfi DNA polymerase might be useful in DNA amplification.




new topics/pols set partial results complete validated


No results available for this paper.

Entry validated by:

Using Polbase tables:


Tables may be sorted by clicking on any of the column titles. A second click reverses the sort order. <Ctrl> + click on the column titles to sort by more than one column (e.g. family then name).


It is also possible to filter the table by typing into the search box above the table. This will instantly hide lines from the table that do not contain your search text.