Characterization of a Temperate Phage and Four Bacteriocins Produced by Nonpathogenic Clostridium Species

We previously reported the isolation of a temperate phage (named KT) and several bacteriocins (named clostocins) from strains of nonpathogenic Clostridium species. Later, the induction and some properties of the phage and four clostocins (A, B, C and D) were examined.

The phage was induced by UV light and mitomycin C. The phage had a polygonal head (about 85mμ in diameter) and a tail with contractile sheath (about 100mμ in length). Some other properties of the phage were also studied; plaque morphology, stability in salt solution, inactivation by UV light, pH stability, thermal inactivation, host-range and lysis of infected culture.

Clostocins A and D were partially induced by UV light and mitomycin C, whereas that of B and C were not. All clostocins failed to pass through a dialysis membrane, and were insensitive to UV light and to ribo- and deoxyribonuclease. They were destroyed by some proteolytic enzymes, but differences in degree of their susceptibility were observed among them. Clostocins A and D were very thermo-stable, whereas B and C were relatively thermo-labile. Clostocins A and D acted on some strains in the genus Clostridium, whereas B and C did on many strains in the family Bacillaceae.

There was no demonstrable serological relationship between phage KT and clostocin A, although they seemed to adsorb on the same bacterial receptor.