ABSTRACT
The ability to cause local tissue damage and hemorrhage is a commonly seen trait in many venoms from front-fanged snakes, and it is generally associated with snake venom metalloproteinases (SVMPs), one of the two types of well-characterized proteinases found in snake venoms. However, a new type of proteolytic enzyme with a completely different origin was shown to be a part of the venom arsenal of some rear-fanged snakes: snake venom matrix metalloproteinases (svMMPs). These enzymes are part of the matrix metalloproteinase (MMP) family of proteinases (also called matrixins), which is one of the four members of the metzincin superfamily of Zn2+ proteinases, together with astacins, serralysins and adamalysins – where traditional SVMPs belong. svMMPs have unique structural features among MMPs, making them a distinct type of metalloproteinase exclusively found in the venoms of some rear-fanged snake groups. In this chapter, we summarize how svMMPs were discovered, present the phylogenetic distribution of this component among rear-fanged snakes, and review the structural, evolutionary and functional information currently available for this new venom proteinase.
