We identified 296 unique proteins separated by shotgun proteomics technique, 30 surface exposed proteins using biotinylation and 67 proteins by Triton X-114 detergent phase partitioning. Combination of different separation techniques with divers in silico analyses revealed 25 possibly beta-barrel outer membrane proteins and 11 proteins enclosing signal peptide sequence. Among these signal peptide containing surface proteins we detected several proteins affecting virulence, like outer membrane protein B, 60 kDa chaperonin GroEL, putative surface antigen and peptidoglycan-associated lipoprotein. The most interesting finding is a unique antigenic 44kDa uncharacterized protein, reacting with serum specimens from R. akari infected patients. This protein is characterized for the first time in present study.