**3. Conclusions**

Snake venom serine proteases have several different functions and have found most use in medicine in blood coagulation system. These enzymes are used in several ways as tools in basic research helping to elucidate the relation of structure- function of coagulant proteins and their interactions with platelets or in experimental models of haemostatic alterations.

Some SVSPs have already been found to be a commercial use in coagulation diagnostic and some of them are used either to influence physiological homeostasis or as a form of supportive treatment in haemostatic disorders and micro vascular surgery promoting cicatrization.

Despite the high homology of serine proteases and even sharing the same target, small differences in their amino acids composition may lead significant binding intensity causing differences in their biological effects. Therefore, even isoforms of those molecules in the same organism must be explored. Many animals besides snakes also possess serine proteases that are used for attack or defense purposes, such as scorpions, bees, spiders and even the exotic platypuses which make 26 different kinds of serine proteases [86].

Therefore, the diversity of those toxins is extensive and demand many research to elucidate their function and potential clinical applications

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