抄録
Employing ultrathin sectioning and negative staining techniques, the reduction sites of tetrazolium salts (nitro blue tetrazolium=NBT, and triphenyl tetrazolium chloride=TTC) and of potassium tellurite in Clostridium botulinum and Cl. Tetani, were examined electron-microscopically. NBT and TTC were reduced to their formazans on or near the intracytoplasmic membrane system (ICMS) and the cytoplasmic membrane. It was presumed that in ultrathin sectioned preparations, owing to the dissolution of formazans in alcohol during the dehydration process, the sites of formazan deposition were seen as electron-transparent spaces among or around the unit membrane elements of the ICMS; moreover, a high tendency the cell wall to detach from the cytoplasmic membrane was noticed.
Potassium tellurite appeared to be reduced mainly on or near the cytoplasmic membrane, but not on the ICMS. This result indicates that the sites of tellurite reduction do not necessarily coincide with those of reduction of tetrazolium salts.
