I. TYPING METHODS FOR CLOSTHIDIUM
5
induction to get an increased production of the active principle. Mahony
and Butler (1971) were unable to induce one strain (strain 28), although
one other strain was later shown to produce a higher titre after treatment
with UV light (Mahony, 1973). I n 1977, Mahony reported the induction
of six of ten bacteriocinogenic strains of C. perfringens using Mitomycin C.
The response to this antibiotic was peculiar in that induction occurred
only after removal of Mitomycin C from the treated culture. Cell death was
associated with induction of bacteriocin.
Sasarman and Antohi (1971) showed that the majority of their welchicinproducing strains gave the highest yield of bacteriocin when grown at the
organism’s optimum growth temperature (37°C). At 50°C bacteriocin was
not produced, and at room temperature production was reduced. Other
investigators have reported a temperature of 37°C for bacteriocin production. Mahony and Butler (1971) studied the production of bacteriocin 28,
and found that optimum production was obtained in the late log phase
between 2 and 3 h after initiation of growth. Uchiyama (196613) found that
maximum titre was achieved after 3 h of growth. In contrast, a bacteriocin
of C. perfringens type A described by Clarke et al. (1975) was released into
the culture fluid in the stationary phase of bacterial growth. With the
method used by Tubylewicz (1966a) bacteriocin production was assayed
after overnight incubation.
Ionesco et al. (1 974) have described independent synthesis of bacteriocin
and bacteriophage in one strain of C. perfringens. Both factors could be
induced by UV light. Bacteriocin production demonstrated a lag period of
70 min while the maximum titre was achieved by 180 min after induction.
3. Host range
All the bacteriocins obtained by Tubylewicz (1966a) were active against
C . perfringens and, under aerobic conditions, did not inhibit :he growth of
37 bacterial strains belonging to ten other genera. Similar results have been
published by Uchiyama (1966a). Sasarman and Antohi (1968) reported a
wider range of activity for a bacteriocin (welchicin A) produced by C.
perfringens type E (strain 1241). In addition to activity against 100% of C.
perfringens tested including the producing strain, they found activity against
Clostridium oedematiens, Clostridium bijermentans, and Clostridium fallax.
Sensitivity to this bacteriocin (welchicin A) was also demonstrated by
various species of the genus Bacillus and subsequently (1971) these workers
also reported activity against Corynebacterium diphtheriae, staphylococci
and streptococci. Sensitivity to a similar host range was later reported by
the same authors (1970), where they showed that welchicin B (produced by
C. perfringens type D, strain 366) was also active on Gram-positive organisms
outside the family Bacillaceae. Sasarman and Antohi (1971), described the
5
induction to get an increased production of the active principle. Mahony
and Butler (1971) were unable to induce one strain (strain 28), although
one other strain was later shown to produce a higher titre after treatment
with UV light (Mahony, 1973). I n 1977, Mahony reported the induction
of six of ten bacteriocinogenic strains of C. perfringens using Mitomycin C.
The response to this antibiotic was peculiar in that induction occurred
only after removal of Mitomycin C from the treated culture. Cell death was
associated with induction of bacteriocin.
Sasarman and Antohi (1971) showed that the majority of their welchicinproducing strains gave the highest yield of bacteriocin when grown at the
organism’s optimum growth temperature (37°C). At 50°C bacteriocin was
not produced, and at room temperature production was reduced. Other
investigators have reported a temperature of 37°C for bacteriocin production. Mahony and Butler (1971) studied the production of bacteriocin 28,
and found that optimum production was obtained in the late log phase
between 2 and 3 h after initiation of growth. Uchiyama (196613) found that
maximum titre was achieved after 3 h of growth. In contrast, a bacteriocin
of C. perfringens type A described by Clarke et al. (1975) was released into
the culture fluid in the stationary phase of bacterial growth. With the
method used by Tubylewicz (1966a) bacteriocin production was assayed
after overnight incubation.
Ionesco et al. (1 974) have described independent synthesis of bacteriocin
and bacteriophage in one strain of C. perfringens. Both factors could be
induced by UV light. Bacteriocin production demonstrated a lag period of
70 min while the maximum titre was achieved by 180 min after induction.
3. Host range
All the bacteriocins obtained by Tubylewicz (1966a) were active against
C . perfringens and, under aerobic conditions, did not inhibit :he growth of
37 bacterial strains belonging to ten other genera. Similar results have been
published by Uchiyama (1966a). Sasarman and Antohi (1968) reported a
wider range of activity for a bacteriocin (welchicin A) produced by C.
perfringens type E (strain 1241). In addition to activity against 100% of C.
perfringens tested including the producing strain, they found activity against
Clostridium oedematiens, Clostridium bijermentans, and Clostridium fallax.
Sensitivity to this bacteriocin (welchicin A) was also demonstrated by
various species of the genus Bacillus and subsequently (1971) these workers
also reported activity against Corynebacterium diphtheriae, staphylococci
and streptococci. Sensitivity to a similar host range was later reported by
the same authors (1970), where they showed that welchicin B (produced by
C. perfringens type D, strain 366) was also active on Gram-positive organisms
outside the family Bacillaceae. Sasarman and Antohi (1971), described the