Production and characterization of the protease pappalysin from Leptospira interrogans

Abstract

Pathogenic Leptospira species are extremely efficient in disseminating and propagating in the host, a fact attributed to their ability to escape the action of the complement system, the first line of defense of the innate immune response, and also to the ability to degrade components of the extracellular matrix and human plasma. The secretion of proteases that inactivate host proteins is an important tool used by several microorganisms during the colonization process. The underlying mechanisms of tissue damage caused by pathogenic leptospires are still poorly understood. Like other bacteria, leptospires cross epithelial and endothelial barriers to access organs. Adhesion and degradation of extracellular matrix components, especially the basement membrane, are certainly necessary for invasion. Recently, our group evaluated the proteolytic activity of proteins present in the culture supernatant of two strains of Leptospira, one pathogenic (virulent) and another saprophytic. The results showed that proteases present only in the supernatant of the virulent strain were able to degrade proteoglycans, fibrinogen and plasma fibronectin. In addition, an analysis of the exoproteome of the above-mentioned virulent strain allowed the identification of some proteases, among them the "pappalysin-1 domain protein" (pappalysin) metalloprotease (EKO25673.1). The objective of this project is to produce and functionally characterize the pappalysin of L. interrogans aiming to increase the knowledge about these metalloproteases of Leptospira in the processes of invasion and immune evasion.