Cloning and expression of animal toxins of biotechnological interest

Abstract

Currently, the interest in the studying chemical and functional characteristics of toxins isolated from animal venoms is not due solely to its relevance in the envenoming, but also for their potential use as valuable research tools. The hyaluronidases from scorpion and snake venoms are enzymes that catalyze the breakdown of hyaluronan, a major component of the extracellular matrix and act as "scattering factor" for accelerating the absorption and diffusion of the venom by tissues of the victims, contributing to the local or systemic envenoming. Although hyaluronidases have been extensively used in various fields of medicine, the number of published studies about this enzyme is reduced, due to its lack of toxicity and the difficulties in purifying of the enzyme from venoms. By the other hand, snake venom serine proteases are considered promising in the development of drugs for treatment of certain hemostatic disorders by acting on specific points of the coagulation cascade, mimicking natural regulatory components. These enzymes act mainly on plasma proteins, platelet aggregation, blood pressure and complement and nervous system. Despite the diversity of pathophysiological actions and pharmacological potential presented by animal toxins, there is a discrepancy between the enormous number of proteins isolated and characterized and the amount of proteins that have become an effective drug, which is due to limitations in obtaining toxins in sufficient quantities to a detailed structural and functional characterization and the impossibility of manipulation of the native molecule. Thus, the heterologous expression of proteins is an alternative for obtaining toxins in laboratory scale for the study of its enzymatic and functional activities. Therefore, this project aims to clone and express hyaluronidase from T. serrulatus and serine proteases from B. pauloensis and C. d. collilineatus venom gland in a heterologous system, which consists of a viable alternative for obtaining them in sufficient quantities to study their enzymatic and biological activities. Furthermore, the comparative study of the toxins in native and recombinant forms can generate prospects for the production of these toxins on an industrial scale, aiming its therapeutic and pharmacological application. (AU)