Dynamics of Aeromonas hydrophila, Aeromonas sobria, and Aeromonas caviae in a sewage treatment pond

Abstract

The spatiotemporal dynamics of Aeromonas spp. and fecal coliforms in the sewage treatment ponds of an urban wastewater center were studied after 20 months of sampling from five stations in these ponds. Isolation and identification of 247 Aeromonas strains were undertaken over four seasons at the inflow and outflow of this pond system. The hemolytic activity of these strains was determined. The Aeromonas spp. and the fecal coliform distributions showed seasonal cycles, the amplitude of which increased at distances further from the wastewater source, so that in the last pond there was an inversion of the Aeromonas spp. cycle in comparison with that of fecal coliforms. The main patterns in these cycles occurred simultaneously at all stations, indicating control of these bacterial populations by seasonal factors (temperature, solar radiation, phytoplankton), the effects of which were different on each bacterial group. The analysis of the Aeromonas spp. population structure showed that, regardless of the season, Aeromonas caviae was the dominant species at the pond system inflow. However at the outflow the Aeromonas spp. population was dominated by A. caviae in winter, whereas Aeromonas sobria was the dominant species in the treated effluent from spring to fall. Among the Aeromonas hydrophila and A. sobria strains, 100% produced hemolysin; whereas among the A. caviae strains, 96% were nonhemolytic.

Diversity of Aeromonas sp. in Flemish drinking water production plants as determined by gas‐liquid chromatographic analysis of cellular fatty acid methyl esters (FAMEs)

“…was noticed. In contrast to the observations of Monfort and Baleux (1990), it appeared that members of the Aer. hydrophda complex and the Aer.…”

“…hydrophila remained the most prominent phenospecies even after aeration of the phreatic groundwater supplies in Eeklo andSnellegem. Schubert (1975, 1976) Monfort and Baleux (1990) also observed that Aer. caviae was the most abundant species at the raw pond system inflow, whereas Aer.…”

Occurrence, diversity and pathogenicity of mesophilic Aeromonas in estuarine waters of the Italian coast of the Adriatic Sea

“…Various studies have also shown that the concentration of Aeromonas spp. in estauries is strongly correlated with temperature as well as with organic nutrients such as phosphate, nitrogen and carbon concentrations (Monfort and Baleux 1990). With respect to the temperature, no seasonal © 1998 The Society for Applied Microbiology, Journal of Applied Microbiology 85, 501-511 cycle in the concentration of Aeromonas spp.…”

Distribution of Aeromonas spp. as identified by 16S rDNA restriction fragment length polymorphism analysis in a trout farm

“…Several reports describe the distribution of Aeromonas spp. and the relationships among Aeromonas spp., indicator bacteria and physical parameters in various environments (Burke et al 1984;Monfort and Baleux 1990;Ortega et al 1996;Pettibone 1998). However, few data are available on the monitoring of the distribution of Aeromonas species identified with reliable methods in fish farms.…”