A non-clotting derivative thrombin produced from Human alpha-Thrombin by controlled incubation with Trypsin-Sepharose. Gamma-thrombin is generated by cleavage of the B-chain at both the Arg106-Tyr107 and Lys190-Gly191 bonds. Gamma-thrombin is a noncoagulant form of thrombin that retains much of its platelet-activating capacity. Gamma-thrombin purity is determined by SDS-PAGE and protein concentration is determined by BCA assay.