Bacteriocin-like Substance of Aeromonas hydrophila

Elisete Moro, Rita Denise Niederauer Weiss, Rosane Salete Friedrich, Marly Paiva Nunes
1997 Memórias do Instituto Oswaldo Cruz  
The genus Aeromonas comprises Gram negative rods found mainly in aquatical environments that may infect humans and animals (JM Janda 1991 Clin Microbiol Rev 4: 397-410). In humans, some Aeromonas species have been associated with intestinal and extraintestinal infections and enterotoxins, cytotoxins as well as invasive mechanisms have been incriminated in the development of illness in the host (Janda loc. cit.). Bacteriocin-like substances (BLS) are protein compounds produced by some bacteria
more » ... Ivanovics 1962 Bacteriol Rev 26: 108-118) showing antagonic activity against their own species (isoinhibitory activity -IA) or other non-related species (heteroinhibitory activity -HA). The use of the expression BLS is recommended to nominate bacterial products showing antagonic activity though not characterized (K Sandhu et al. 1983 J Clin Microbiol 17: 511-515). These substances have been widespread utilized in epidemiological studies as specific marker properties of bacteria, in the regulation of population dynamics in bacterial ecosystems and clinical treatment (V Fantinato & F Zelante 1991 Rev Microbiol 22: 49-51). As BLS have not been currently described in Aeromonas species, the purpose of this study was to investigate their production in strains isolated from animal, clinical and environmental sources. The assays for the production of BLS were performed according to Sandhu et al. (loc. cit.). The strains used as BLS producers and BLS indicators are listed in Table. Our results showed that among 32 Aeromonas strains, the BLS could be only demonstrated in a strain of A. hydrophila isolated from a water tank containing alligators. This strain demonstrated heteroinhibitory activity against four Staphylococcus aureus strains (one ATCC 6538 and three methicillin-resistant -MRSA). The heteroinhibitory activity was demonstrated after an incubation of 48 hr at 37°C and not at 25°C, conditions also observed for the BLS production in Serratia, Pseudomonas, Leuconostoc and Enterococcus strains (JD Foulds & D Shemin 1969
doi:10.1590/s0074-02761997000100024 pmid:9302421 fatcat:aq7untadtbd33ksxage62efrem