Rapid detection of the Chlamydiaceae and other families in the order Chlamydiales: Three PCR tests

Few identification methods will rapidly or specifically detect all bacteria in the order Chlamydiales, family Chlamydiaceae. In this study, three PCR tests based on sequence data from over 48 chlamydial strains were developed for identification of these bacteria. Two tests exclusively recognized the Chlamydiaceae: a multiplex test targeting the ompA gene and the rRNA inter genic spacer and a TaqMan test targeting the 23S ribosomal DNA. The multipl ex test was able to detect as few as 200 inclusion-forming units (IFU), whi le the TaqMan test could detect 2 IFU. The amplicons produced in these test s ranged from 132 to 320 bp in length. The third test, targeting the 23S rR NA gene, produced a 600-bp amplicon from strains belonging to several famil ies in the order Chlamydiales. Direct sequence analysis of this amplicon ha s facilitated the identification of new chlamydial strains. These three tes ts permit ready identification of chlamydiae for diagnostic and epidemiolog ic study. The specificity of these tests indicates that they might also be used to identify chlamydiae without culture or isolation.