It is an in silico designed homologue of Bacillus
stearothermophilus DNA Polymerase I, Large Fragment (Bstl DNA Polymerase, Large Fragment) with a reversibly-bound aptamer, which inhibits polymerase activity at temperatures below 50°C. The aptamer rapidly releases the Bstl DNA Polymerase above 50°C and therefore no special activation step is needed to activate the polymerase.
Bstl DNA Polymerase contains 5′-3′ DNA polymerase activity and strong strand displacement activity but lacks 5′-3′ exonuclease activity. Bst DNA Polymerase displays improved amplification speed, yield, salt tolerance, and thermo stability compared to wild-type Bstl DNA Polymerase, Large Fragment.