Ultracentrifugation of Acetylated Thrombin^[*]

Summary

Acetylated bovine thrombin with a specific activity of 5930 units per milligram dry weight was found to be homogeneous by ultracentrifuge analysis. The sedimentation constant in units of 10⁻¹³ sec. at 20° C, in 0.1 M potassium chloride was 3.3. This constant is not concentration dependent.

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