V. Benoit et al., CHARACTERIZATION OF BREVICIN 27, A BACTERIOCIN SYNTHESIZED BY LACTOBACILLUS-BREVIS-SB27, Current microbiology, 28(1), 1994, pp. 53-61
Lactobacillus brevis SB27, isolated from sausages, produced an antimic
robial substance active against numerous strains of heterofermentative
lactobacilli and against some strains of pediococci and Bacillus. The
antibacterial agent was shown to be heat stable, resistant over a wid
e pH range, and sensitive to proteolytic enzymes. It was identified as
a bacteriocin and termed brevicin 27. Dialysis and ultrafiltration su
ggested an apparent molecular weight between 10 and 30 kDa for the cru
de inhibitory molecule. Brevicin 27 exhibited a hydrophobic character.
A partially purified preparation, resulting from ammonium sulfate pre
cipitation and cation exchange chromatography, permitted confirmation
of some characteristics of the bacteriocin, previously established wit
h the crude extract. After treatment of the original brevicin 27-produ
cing strain with novobiocin, a nonproducing mutant was obtained. This
mutant was sensitive to brevicin 27, and its plasmid profile revealed
the loss of a plasmid of about 3 MDa.