Structural analysis and serological test of arginine periplasmic binding protein 2 from Chlamydophila pneumoniae

► The crystal structure of Cpb0502 was determined to be a dimer at 2.07 Å. ► We identified the arginine binding site in negatively charged 'hole-like sites'. ► Cpb0502 can be used as a candidate antigen to detect C. pneumoniae.