Antimicrobial substances produced by coliform strains active against foodborne pathogens.
In the present study, 31 coliform strains were isolated from salad, cheese, and meat products sold in commercial establishments in Rio de Janeiro city, and were tested for antibiotic resistance and antimicrobial substance production. Thirteen strains (41.9%) were resistant to at least one antibiotic tested, among which one presented resistance to nine different antibiotics. Two strains (6.4%) exhibited inhibitory activity against the indicator strains, Escherichia coli LMIFRJ and Salmonella enterica I. The antimicrobial substances that they produced were sensitive to proteolytic enzymes, suggesting that they might be bacteriocins. The producer strains were identified as Klebsiella ozaenae and Raoultella terrigena. Although they had similar spectrums of action, the bacteriocins were shown to be different. Both of them were able to inhibit E. coli, Klebsiella, Enterobacter, and Salmonella strains, including antibiotic-resistant ones. Our results suggest that these bacteriocins, named klebicin K and raoultellin L, could have potential use against some foodborne pathogens.
Fleming
Luana Rocha
LR
Laboratory of Microbiology, Federal Institute of Education, Science, and Technology of Rio de Janeiro (IFRJ), Rio de Janeiro, RJ, Brazil.
Bolzan
Dayana Nascimento
DN
Nascimento
Janaína Dos Santos
Jdos S
D000818:Animals; D000900:Anti-Bacterial Agents / Q000378:metabolism* / Q000494:pharmacology*; D001430:Bacteriocins / Q000096:biosynthesis / Q000494:pharmacology; D002611:Cheese / Q000382:microbiology; D004754:Enterobacter / Q000187:drug effects; D004755:Enterobacteriaceae / Q000302:isolation & purification / Q000378:metabolism*; D004926:Escherichia coli / Q000187:drug effects; D005517:Foodborne Diseases / Q000382:microbiology*; D007709:Klebsiella / Q000187:drug effects / Q000378:metabolism; D018545:Lactuca / Q000382:microbiology; D008461:Meat Products / Q000382:microbiology; D012475:Salmonella / Q000187:drug effects
D000900:Anti-Bacterial Agents; D001430:Bacteriocins