Characterization of Ammonia Oxidizing Bacteria in an Activated Sludge Plant using a Fluorescent in situ Hybridization Method

Authors : Gülnur COŞKUNER

Pages : 1-7

View : 17 | Download : 7

Publication Date : 2004-12-01

Article Type : Research Paper

Abstract :The spatial arrangement of functionally important ammonia oxidizing bacteria insert ignore into journalissuearticles values(AOB); in activated sludge flocs is largely unknown and activated sludge flocs are regarded as heterogeneous agglomerations of bacterial communities. This study aimed to determine both the location of AOB microcolonies within flocs and the size variation of these microcolonies based on their location. Fluorescent in situ hybridization insert ignore into journalissuearticles values(FISH); was used in combination with a confocal scanning laser microscope insert ignore into journalissuearticles values(CSLM); to achieve these goals. Grab samples taken from a full-scale plug flow wastewater treatment plant were examined with probes targeted to AOB b-Proteobacteria insert ignore into journalissuearticles values(Nso1225); and a genus specific probe targeted to the genus Nitrosospira insert ignore into journalissuearticles values(Nsv443);. Frequencies of AOB microcolonies were observed to increase towards the center of activated sludge flocs insert ignore into journalissuearticles values(ASFs);. In addition, the size of AOB microcolonies was found to rise from the edges to the centers of flocs. This study indicates that ASFs might have a non-random agglomeration of AOB microcolonies. However, FISH is a relatively preliminary method for the aims targeted in this study and the results are not sufficient to justify definite conclusions.
Keywords : Activated Sludge Flocs, Ammonia Oxidizing Bacteria, Confocal Scanning Laser Microscopy, Fluorescent in Situ Hybridization