Detection and Characterization of the Hemolysin Genes in Aeromonas hydrophila and Aeromonas sobria by Multiplex PCR
AUTOR(ES)
Wang, Gehua
FONTE
American Society for Microbiology
RESUMO
A multiplex PCR assay was designed to amplify the Aeromonas hydrophila and A. veronii bv. sobria hemolysin and aerolysin genes. The assay was evaluated by using 121 clinical isolates and 7 reference strains of Aeromonas spp., and these were divided into five genotypes on the basis of the results of the multiplex PCR. The five genotypes were characterized as type 1 for those carrying the ahh1 gene only (36% of isolates), type 2 for those carrying the asa1 gene only (8.5% of isolates), type 3 for those carrying both the ahh1 and the asa1 genes (4% of isolates), type 4 for those carrying the ahh1 gene and the A. hydrophila aerA (aerolysin) gene (37.5% of isolates), and type 5 for those in which no hemolysin genes were detected (14% of isolates). The most common single hemolysin gene carried among all the Aeromonas isolates examined was ahh1, with 99 of 128 (77%) of isolates testing positive for this gene either alone or in combination with other hemolysin genes. Phenotypic expression of toxins was evaluated in a Vero cell culture cytotoxicity assay. These results indicated that there is a statistically significant correlation between the cytotoxin titers and the hemolysin genotype. Isolates belonging to genotype 4 (carrying both the ahh1 gene and the aerolysin and hemolysin aerA genes) expressed higher cytotoxin titers than isolates of the other genotypes (P < 0.001). These isolates were more cytotoxic in cell culture and may have greater clinical significance.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=150266Documentos Relacionados
- Characterization of Aeromonas sobria hemolysin by use of monoclonal antibodies against Aeromonas hydrophila hemolysins.
- Purification and characterization of an Aeromonas hydrophila hemolysin.
- Identification of hydroxy fatty acids in Aeromonas hydrophila, Aeromonas sobria, and Aeromonas caviae.
- Dynamics of Aeromonas hydrophila, Aeromonas sobria, and Aeromonas caviae in a sewage treatment pond.
- In vitro susceptibilities of Aeromonas hydrophila, Aeromonas sobria, and Aeromonas caviae to 22 antimicrobial agents.