Dynamics of plc gene transcription and a-toxin production during growth of Clostridium perfringens strains with contrasting a-toxin production

The aim of the present study was to investigate transcription dynamics of the a-toxin-encoding plc gene relative to two housekeeping genes (gyrA and rplL) in batch cultures of three Clostridium perfringens strains with low, intermediate, and high levels of a-toxin production, respectively. The plc transcript level was always low in the low a-toxin producing strain. For the two other strains, plc transcription showed an inducible pattern and reached a maximum level in the late exponential growth phase. The transcription levels were however inversely correlated to a-toxin production for the two strains. We propose that this discrepancy is due to differences in plc translation rates between the strains and that strain-specific translational rates therefore must be determined before a-toxin production can be extrapolated from transcript levels in C. perfringens.