Categories Uncategorized Prothrombinase Refers to factor Xa complexed with factor V. Cleaves prothrombin to form thrombin, which generates fibrin from fibrinogen. ← Proteolytic systems → Protooncogenes Leave a Reply Cancel replyYour email address will not be published. Required fields are marked *Comment * Name * Email * Website Save my name, email, and website in this browser for the next time I comment.