Transcriptional analysis of fim2 . A schematic map of the fim2 cluster and the upstream orf10 gene to show regions targeted for transcriptional analysis: fim2K (PCR-1, 220 bp: PR1611/PR1612), fim2H-fim2K (PCR-2, 316 bp: PR16268/PR1629), fim2H (PCR-3, 241 bp: PR1609/PR1610), fim2A (PCR-4, 221 bp: PR1607/PR1608) and fim2A-orf10 (PCR-5, 380 bp: PR1626/PR1627). RNA purified from an in vitro grown culture of KR2107 (LB, 37°C, 200 rpm, 16 h) was processed in parallel with (+) or without (−) reverse transcriptase and analysed by PCR with the primers listed above. KR2107 genomic DNA (g) and PCR-grade water (Neg) were used as PCR controls when necessary. Amplicons were visualised on 1.5% agarose gels. Distinct PCR amplicons were obtained for four of the five assays. The PCR-5 assay which sought to define a shared orf10 and fim2A transcript was negative.