Transcriptional analysis of the groESL operon from Porphyromonas gingivalis

Transcriptional analysis of the groESL operon from Porphyromonas gingivalis, one of the obligative anaerobic oral microorganisms implicated in adult periodontitis, was performed. P. gingivalis 381 cultured at 37°C was shifted to 42°C, 45°C or 48°C for 10 mins. Northern hybridization analysis revealed that a band with 2.1-kb (kilo base pair) was observed, and the transcripts increased greatly by heat shock. Primer extension and S1 mapping detected four different 5'-ending sites of the mRNAs at the upstream region of the groES. Three sites out of the four were heat-inducible. There were inverted repeats and a Escherichia coli σ³²-recognizing consensus sequence in the promoter region of the groESL, which may be relevant to the regulation of transcription of groESL operon in P. gingivalis. Both a heat shock promoter and inverted repeats may be relevant to the transcriptional regulation of the groESL operon in P. gingivalis.