Comparison of immunofluorescence colony-staining in media, selective isolation on pectate medium, ELISA and immunofluorescence cell staining for detection of Erwinia carotovora subsp. atroseptica and E. chrysanthemi in cattle manure slurry

Autor: Van Vuurde, J. W. L., Roozen, N. J. M.
Zdroj: European Journal of Plant Pathology; March 1990, Vol. 96 Issue: 2 p75-89, 15p
Abstrakt: Various isolation and serological techniques were compared for the detection ofErwinia carotovora subsp.atroseptica (Eca) andE. chrysanthemi (Ech) in cattle manure slurry containing c. 108 colony forming units (cfu) per ml. The slurry samples could be preserved at −80°C for 8 months without reduction in the number of bacteria but not at −20°C. Samples stored at −80°C were inoculated with concentrations of the target bacterium ranging from 102 to 108 per ml. Only immunofluorescence colony-staining (IFC) in combination with selective media was able to detect the target organism at a concentration of 100 cells per ml. No IFC-positive colonies were found in pour plates of the non-inoculated cattle slurry. The recovery of the target bacterium from slurry inoculated with 102 cfu of Ech per ml was 64% in PT medium (containing polygalacturonic acid) and 19% in crystal violet pectate medium (CVP). Recoveries of Eca were 32% and 82%, respectively. Ech and Eca could be detected at levels of 103 cfu per ml of slurry by isolation on CVP. Crude filtration procedures were necessary for analysis of slurry samples with immunosorbent immunofluorescence (ISIF) cell staining. The detection level of ISIF for Ech was 105 cells per ml of slurry. IF-positive cells were incidentally observed in the non-inoculated slurry. Detection of Ech and Eca with ELISA was only possible in slurry inoculated with 108 cells of the target bacterium per ml.
Databáze: Supplemental Index