ABSTRACT
Secreted phospholipases A2 (sPLA2s) are almost universally expressed in snake venoms, often representing a major portion of their protein components. Snake venom sPLA2s belong mainly to two structurally distinct groups, GIIA, present in viperid snakes, and GIA, present in elapid snakes. The wide diversity of toxic functionalities acquired by sPLA2s during the evolution of venomous snakes highlights the high “plasticity” of the structural scaffold of these interfacial enzymes and their enzymatically inactive (sPLA2-like) variants. In spite of important advances in the structural and functional characterization of a large number of snake venom sPLA2s, our present understanding of the specificity and mechanisms of their main toxic actions and bioactivities remains limited, with many key questions still to be answered. Deeper studies on sPLA2 toxins from snake venoms may provide relevant clues to counteract the severe pathological consequences of envenomings and also to broaden our knowledge of the many processes in which mammalian sPLA2s are involved, both in health and in disease. The present chapter offers a general overview of the current status and recent advances in understanding snake venom sPLA2s, with a focus on their medically most relevant actions.
