What is the point of using proteolytic cleavage to activate complement? Why not just have the molecules made in their active form? What kinds of evasive action could a bacterium take to prevent itself...

What is the point of using proteolytic cleavage to activate complement? Why not just have the molecules made in their active form?

What kinds of evasive action could a bacterium take to prevent itself from being killed by a phagocyte? (Hint: consider the steps in the killing process.)