Sequence Homologies between Mycoplasma and Chlamydia spp. Lead to False-Positive Results in Chlamydial Cell Cultures Tested for Mycoplasma Contamination with a Commercial PCR Assay

Abstract

Mycoplasma contamination is a frequent problem in chlamydial cell culture. After obtaining contradictory contamination results, we compared three commercial PCR kits for mycoplasma detection. One kit signaled contamination in mycoplasma-free Chlamydia pneumoniae cultures. Sequencing of cloned PCR products revealed primer homology with the chlamydial genome as the basis of this false-positive result.