Partial purification and characterization of the mode of action of enterocin S37: A bacteriocin produced by enterococcus faecalis S37 isolated from poultry feces

The aim of this research was to purify and characterize the mode of action of enterocin s37,a bacteriocin produced by enterococcus faecalis s37,a strain recently isolated from the chicken feces. enterocin s37 has a molecular weight comprised between 4 and 5kda. it remained active after 1h at 80 o c and at ph values ranging from 4.0 to 9.0. furthermore,cell-free supernatant of enterococcus faecalis s37 and purified enterocin s37 were active against gram-positive bacteria including listeria monocytogenes egde,l. innocua f,enterococcus faecalis jh2-2,and lactobacillus brevis f145. the purification of enterocin s37 was performed by ammonium sulfate precipitation followed up by hydrophobic-interaction chromatography procedures. treatment of enterocin s37 with proteinase k,-chymotrypsin,and papain confirmed its proteinaceous nature,while its treatment with lysozyme and lipase resulted in no alteration of activity. enterocin s37 is hydrophobic,anti-listeria and likely acting by depletion of intracellular k ions upon action on k atp channels. this study contributed to gain more insights into the mode of action of enterocins. © 2010 y. belguesmia et al.