One strain of Lactobacillus acidophilus was found to produce
a bacteriocin-like substance in the culture filtrate. The substance
was produced in a growth-associated manner, showed
heat stability at neutral and acidic pH and exhibited antibacterial
activity against various species of Lactobacillus including
L. acidophilus itself. The molecular weight of the substance
was in the range of 6.2–9.5 kDa. N-terminal amino acid
sequence analysis suggests that the substance may belong to
class IIb bacteriocin