1. Acrosin is the major proteinase present in the acrosome of mature spermatozoa. 2. This latter protein is an evolutionary homology of the picornavirus 3C proteinase . 3. This protein is a member of the serpin superfamily of serine proteinase inhibitors. 4. Proteinase but that won't fly because we are talking ink stain.5. Both the ZP2 proteinase and trypsin-like proteinase contribute to polyspermy prevention. 6. Both the ZP2 proteinase and trypsin-like proteinase contribute to polyspermy prevention. 7. As its name suggests, ZP2 proteinase proteolyzes ZP2 during the zona reaction. 8. Thrombin is a serine proteinase that plays a central role in the thrombotic process. 9. MMP inhibitors could also be administered along with cytotoxic agents or other proteinase inhibitors. 10. The proteasome is a multicatalytic proteinase complex with a highly ordered 20S core structure.