Application of a Mycoplasma group-specific PCR for monitoring decontamination of Mycoplasma-infected Chlamydia sp. strains.

Mycoplasma contamination of biological materials remains a major problem. Most contaminations are caused by the use of Mycoplasma-contaminated cell lines. We adapted a Mycoplasma group-specific PCR to detect Mycoplasma contamination in cell lines and demonstrate its use in monitoring decontamination procedures with Mycoplasma-contaminated suspensions of Chlamydia spp. Three different methods were investigated: the use of Mycoplasma-specific antiserum in cell culture, physical separation by the combined use of enzymatic treatment and differential centrifugation, and the use of detergents. With these methods only incubation with Triton X-100 resulted in decontamination of Mycoplasma-contaminated suspensions of several laboratory strains of Chlamydia pneumoniae, C. pecorum, and C. trachomatis. Only one C. pneumoniae strain, UZG-1, was sensitive to Triton X-100 treatment. Since 39 of 40 throat swabs from patients with symptoms of an upper respiratory tract infection had positive reactions in the Mycoplasma group-specific PCR, this procedure could also have clinical significance in attempts to propagate C. pneumoniae strains from clinical specimens.