Genome analysis of Leptospira interrogans serovar Copenhageni reveals the presence of proteins that share a unique conserved domain of unknown function (DUF1554). DUF1554 containing proteins are found exclusively among pathogenic Leptospira spp., and resemble protein motifs within the C-type lectin protein superfamily. To characterize these proteins further seven fusion proteins from the Leptospira interrogans serovar Copenhageni genome were expressed and purified in Escherichia coli. These fusion proteins were used to produce polyclonal antiserum in New Zealand white rabbits. Titers were determined by Western blot and antibodies were used to localize the protein in whole cell sonicate and outer membrane fractions. Polyclonal antiserum was also used to show in vivo and in vitro expression of the proteins. Localization of these proteins is mostly in the outer membrane. The function of these domains has not been determined. C-type lectin-like proteins may play a role in adhesion to extracellular matrix and may be a potential virulence factor in the pathology of leptospirosis.