Antibody for detecting chlamydia pneumoniae

A method for specifically, highly sensitively and quickly detecting a microorganism belonging to Chlamydia penumoniae; an antibody to be used in the detection; a detection reagent kit; and a process for producing the antibody to be used in the detection. Namely, an antibody against the ribosomal protein of a microorganism belonging to C. penumoniae which reacts specifically with this microorganism; a method of detecting the microorganism in a specimen by using this antibody; and a detection reagent kit containing this antibody. The ribosomal protein is exemplified by Ribosomal Protein L7/L12 and this method is usable in detecting the infection with a microorganism causative of pneumonia.