Molecular detection of enterotoxins in environmental strains of Aeromonas hydrophila and Aeromonas jandaei.
Aeromonas species are widely distributed in aquatic environments and recent studies include the genus in the emergent pathogens group because of its frequent association with local and systemic infections in immunocompetent humans. Aiming to search for virulence genes in environmental strains of Aeromonas hydrophila and Aeromonas jandaei, we designed specific primers to detect act/hlyA/aer complex and alt genes. Primers described elsewhere were used to detect ast. Eighty-seven strains previously identified using phenotypic and genotypic tests as A. hydrophila (41) and A. jandaei (46) were analysed for the presence of the virulence genes using PCR. DNA fragments of expected size were purified and directly sequenced. Among the 41 strains of A. hydrophila 70.7% (29), 97.6% (40) and 26.8% (11) possessed act/hlyA/aer complex, ast and alt genes, respectively. Among the 46 strains of A. jandaei, 4.4% (2), 0% (0) and 32.6% (15) were positive for act/hly A/aer complex, ast and alt genes, respectively. Sequencing allowed for the confirmation of amplified products using BLAST. The present work proposes a specific and rapid diagnostic method to detect the main virulence determinants of Aeromonas, a genus potentially pathogenic to humans.
Balsalobre
L C
LC
School of Public Health, University of São Paulo, Avenida Doutor Arnaldo 715, 01246-904 São Paulo, SP, Brazil. liviabalsalobre@usp.br
Dropa
M
M
Matté
G R
GR
Matté
M H
MH
D000333:Aeromonas / Q000235:genetics* / Q000472:pathogenicity; D016980:Aeromonas hydrophila / Q000235:genetics; D001426:Bacterial Proteins / Q000032:analysis / Q000235:genetics; D001483:Base Sequence; D017931:DNA Primers; D004269:DNA, Bacterial / Q000737:chemistry; D004768:Enterotoxins / Q000032:analysis* / Q000235:genetics; D004781:Environmental Exposure / Q000032:analysis; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D016415:Sequence Alignment; D014774:Virulence / Q000235:genetics; D037521:Virulence Factors / Q000032:analysis* / Q000235:genetics; D014871:Water Microbiology
D001426:Bacterial Proteins; D017931:DNA Primers; D004269:DNA, Bacterial; D004768:Enterotoxins; D037521:Virulence Factors; C082174:cytolytic enterotoxin protein, Aeromonas