PROMOTING ACCESS TO AFRICAN RESEARCH

Libyan Journal of Medicine

Log in or Register to get access to full text downloads.

Remember me or Register



Genospecies and virulence factors of Aeromonas species in different sources in a North African country

KS Ghenghesh, SF Ahmed, P Cappuccinelli, JD Klena

Abstract


Introduction: Aeromonads of medical importance have been reported from numerous clinical, food, and water sources, but identification of genospecies and virulence factors of Aeromonas species from countries in North Africa and the Middle East are few.
Methods: In total 99 Aeromonas species isolates from different sources (diarrheal children [n=23], nondiarrheal children [n=16], untreated drinking water from wells [n=32], and chicken carcasses [n=28]) in Tripoli, Libya, were included in the present investigation. Genus identification was confirmed by biochemical analysis, and genospecies were determined using a combination of 16S rDNA variable region and gyrB sequence analysis. Polymerase chain reaction (PCR) was used to detect genes encoding toxins from 52 of the isolates.
Results: We identified 44 isolates (44%) as A. hydrophila (3 [3.0%] subspecies anaerogenes, 23 [23%] subspecies dhakensis, and 18 [18%] subspecies ranae); 27 isolates (27%) as A. veronii; 23 isolates (23%) as A. caviae; and 5 isolates (5.0%) as other genospecies. The genes encoding aerolysin (aer), cytolytic enterotoxin (act), and A. hydrophila isolate SSU enterotoxin (ast) were detected in 45 (87%), 4 (7.7%), and 9 (17%) of the 52 isolates tested, respectively. The gene encoding an extracellular lipase (alt) was not detected.
Conclusion: The majority of aeromonads from Libya fall within three genospecies (i.e. A. hydrophila, A. veronii, and A. caviae), and genes coding for toxin production are common among them.

Keywords: Aeromonas; genospecies; virulence factors; Libya




http://dx.doi.org/10.3402/ljm.v9.25497
AJOL African Journals Online