Antithrombin-resistant prothrombin Yukuhashi mutation also causes thrombomodulin resistance in fibrinogen clotting but not in protein C activation.

•We report effects of the prothrombin Yukuhashi mutation on TM–PC anticoagulant system.•rTM inhibits fibrinogen-clotting activity of the mutant thrombin insufficiently.•The mutation may cause TM resistance in fibrinogen-clotting inhibition.•rTM equally enhances APC generation activities of the mutant and wild-type thrombins.•The mutation may not cause TM resistance in the enhancing effect of APC generation.