Most thermostable polymerases are not inherently processive. Generally, they extend only a few bases before falling off of the primed template. Due to this dissociative nature, even a short fragment requires numerous polymerase binding events to complete elongation. Inefficient or incomplete elongation results in an overall decrease in reaction efficiency and requires longer extension times and increased enzyme concentrations to ensure template completion. Polymerase performance is further challenged by long or difficult templates, resulting in lower yields and a higher rate of reaction failures.
By fusing a particular double-stranded DNA binding domain to the polymerase, its processivity can be increased 10-fold. Phusion® DNA Polymerase exploits this dramatic increase in processivity, resulting in shorter extension times, more robust and high yield amplification, and the ability to amplify long templates in a fraction of the time.
Phusion® was developed by Finnzymes Oy, now a part of Thermo Fisher Scientific. This product is manufactured by New England Biolabs, Inc. under agreement with, and under the performance specifications of Thermo Fisher Scientific.