Isolation and purification of enterocin E-760 with broad antimicrobial activity against gram-positive and gram-negative bacteria.
Strain NRRL B-30745, isolated from chicken ceca and identified as Enterococcus durans, Enterococcus faecium, or Enterococcus hirae, was initially identified as antagonistic to Campylobacter jejuni. The isolate produced a 5,362-Da bacteriocin (enterocin) that inhibits the growth of Salmonella enterica serovar Enteritidis, S. enterica serovar Choleraesuis, S. enterica serovar Typhimurium, S. enterica serovar Gallinarum, Escherichia coli O157:H7, Yersinia enterocolitica, Citrobacter freundii, Klebsiella pneumoniae, Shigella dysenteriae, Pseudomonas aeruginosa, Proteus mirabilis, Morganella morganii, Staphylococcus aureus, Staphylococcus epidermidis, Listeria monocytogenes, Campylobacter jejuni, and 20 other Campylobacter species isolates. The enterocin, E-760, was isolated and purified by cation-exchange and hydrophobic-interaction chromatographies. The proteinaceous nature of purified enterocin E-760 was demonstrated upon treatment with various proteolytic enzymes. Specifically, the antimicrobial peptide was found to be sensitive to beta-chymotrypsin, proteinase K, and papain, while it was resistant to lysozyme and lipase. The enterocin demonstrated thermostability by retaining activity after 5 min at 100 degrees C and was stable at pH values between 5.0 and 8.7. However, activity was lost below pH 3.0 and above pH 9.5. Administration of enterocin E-760-treated feed significantly (P < 0.05) reduced the colonization of young broiler chicks experimentally challenged and colonized with two strains of C. jejuni by more than 8 log(10) CFU. Enterocin E-760 also significantly (P < 0.05) reduced the colonization of naturally acquired Campylobacter species in market age broiler chickens when administered in treated feed 4 days prior to analysis.
Line
J E
JE
USDA-ARS, Russell Research Center, Poultry Microbiological Safety Research Unit, 950 College Station Rd., Athens, GA 30604, USA. eric.line@ars.usda.gov
Svetoch
E A
EA
Eruslanov
B V
BV
Perelygin
V V
VV
Mitsevich
E V
EV
Mitsevich
I P
IP
Levchuk
V P
VP
Svetoch
O E
OE
Seal
B S
BS
Siragusa
G R
GR
Stern
N J
NJ
D000818:Animals; D001430:Bacteriocins / Q000737:chemistry / Q000145:classification / Q000302:isolation & purification / Q000494:pharmacology; D016123:Campylobacter jejuni / Q000187:drug effects; D002432:Cecum / Q000382:microbiology; D002645:Chickens / Q000382:microbiology; D016983:Enterococcus / Q000145:classification / Q000302:isolation & purification / Q000378:metabolism*; D006090:Gram-Negative Bacteria / Q000187:drug effects*; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D012426:Russia
D001430:Bacteriocins