Traumatic fifth finger amputation due to pontoon boat railing design.

BACKGROUND: Boating is a common recreational activity that may subject its participants to specific patterns of injury. OBJECTIVES: We describe two unrelated cases of fifth-finger amputation associated with a specific pontoon boat guardrail design. CASE REPORT: The individuals in these cases sustained an avulsion-type amputation injury to the fifth finger when their fingers became entrapped in a narrowed portion of the boat railing before jumping into the water. CONCLUSIONS: Given the widespread use of this type of recreational boat, this apparent design flaw may place additional individuals at risk of significant hand injury with cosmetic and functional loss. Methods to reduce the public health impact of this type of injury are also discussed.

A novel strategy to engineer DNA polymerases for enhanced processivity and improved performance in vitro.

Mechanisms that allow replicative DNA polymerases to attain high processivity are often specific to a given polymerase and cannot be generalized to others. Here we report a protein engineering-based approach to significantly improve the processivity of DNA polymerases by covalently linking the polymerase domain to a sequence non-specific dsDNA binding protein. Using Sso7d from Sulfolobus solfataricus as the DNA binding protein, we demonstrate that the processivity of both family A and family B polymerases can be significantly enhanced. By introducing point mutations in Sso7d, we show that the dsDNA binding property of Sso7d is essential for the enhancement. We present evidence supporting two novel conclusions. First, the fusion of a heterologous dsDNA binding protein to a polymerase can increase processivity without compromising catalytic activity and enzyme stability. Second, polymerase processivity is limiting for the efficiency of PCR, such that the fusion enzymes exhibit profound advantages over unmodified enzymes in PCR applications. This technology has the potential to broadly improve the performance of nucleic acid modifying enzymes.