Leptospirosis is an infectious disease that affects humans and animals, being a zoonotic disease of global importance accounting for more than 100.000 cases diagnosed in humans and leading to 1.000 deaths per year. The etiologic agents of this disease are gram-negative bacteria of the Leptospira genus, the most pathogenic species being Leptospira interrogans. Leptospira infection causes a systemic disease that can be asymptomatic or may develop into renal and hepatic dysfunction, causing even aseptic meningitis and death. The bacterial surface proteins play an important role in the physiopathological context of infections; various Leptospiral surface proteins have been shown to be recognized by human antibodies. Hence, the use of conserved protein antigens is one of the major strategies in the development of more efficient vaccines and diagnostic tools. A family of heat-shock proteins, called HtrA, with serine-protease and chaperone activity, has been described. In this study we aim to characterize the gene encoding a probable HtrA protein described in the annotation of the L. interrogans, serovar Copenhageni, genome project. Two genes, htrALi1 and htrALi2 were selected, amplified by PCR and cloned using the pBad/thio-TOPO system (Invitrogen). The HtrALi1 recombinant protein (rHtrAli1) was obtained after expression in Escherichia coli. Culture conditions were optimized aiming to obtain the recombinant protein in soluble form. rHtrAli1 was purified from induced cultures through affinity chromatography (Ni²⁺-IMAC). The recombinant protein showed the expected molecular mass, similar to HtrA proteins described in other organisms. A polyclonal sera was produced in mice and is being used for confirmation of in vivo expression of HtrA.