Comparing the protein profiles of 21 different activated sludge systems after SDS-PAGE

The bacterial community structure of phosphate removing activated sludge sy stems were compared. Samples were obtained from 21 different activated slud ge systems, differing in design and phosphorus removal. Community structure s were determined in a more direct manner by isolation of the total protein content of samples which alleviated the need to culture the bacteria. Prot eins of the activated sludge samples were separated with SDS-polyacrylamide gel electrophoresis (SDS-PAGE). The objectives of this study were: to comp are the protein fingerprints of activated sludge systems which differ in de sign and P-removal. The results indicated little variation between the diff erent zones. The specific sludge systems tended to cluster together indicat ing a specific community structure for each system. However, this did not i nfluence the P-removing capacity of the different systems studied, indicati ng that the microbial community structure was not specific in terms of its P-removing ability. (C) 1999 Elsevier Science Ltd. All rights reserved.