i Nitrite/nitrate levels going in to the activated sludge Selumetinib purchase tanks (g/s). Table 6 Correlations between TRF abundances and sludge and effluent water parameters a AluI Identityb, c Observationsd SSVIe Shear sensitivityf EPS proteing EPS carb.h Effluent NSSi AluI 142 Methanosarcina b 2         *** AluI 176 Methanosaeta c 24           AluI 184 Methanosaeta c 33       *** *** AluI 185 ARC I c 2     * ***   RsaI RsaI 74 Methanosaeta c 31     * ***   RsaI 142 Euryarchaeota b 3     ** *** *** RsaI 238 Methanosaeta c 31         *** RsaI 259 ARC I c 4     ** *** *** a The correlations are marked with asterisks corresponding to the level of statistical significance:

95% (*), 99% (**) and 99.9% (***). this website TRFs that are not included did not show any statistically significant correlation with any parameter. The sludge and effluent water parameter data was taken from [22]. b Identification by comparison with the RDP database. c Identification by comparison with the clone library. d The number of times the TRF was observed. e Standardized sludge volume index (ml/g). f Shear sensitivity (arbitrary units). g EPS protein (mg/gMLSS). h EPS carbohydrates (mg/gMLSS). i Effluent non-settleable solids (mg/l). Quantification and localization of Archaea in the activated sludge flocs The 16S rRNA gene clone library indicated that published

FISH probes would cover the Archaea at Rya WWTP. Archaea could be observed in the activated sludge flocs, both centrally located and close to the edges of the flocs. FISH analyses showed that the average relative SBE-��-CD research buy abundance of Archaea in the activated sludge of the aeration tank was 1.6% (Figure  9). In the anaerobic digester and in the water recycled into the activated sludge tanks (reject water) there were more Archaea than Bacteria (Figure  9). In most images of activated sludge flocs the percentage of Archaea was lower than 2% (Figure 

10). Occasionally there were larger colonies of Archaea (Figure  11, panel A) but in most images Archaea were either present as individual cells or small colonies (Figure  11, panel B). Figure 9 Quantification of Archaea . Confocal images were collected from triplicate samples from the aeration tank, reject water and the digester. A threshold of 100 was applied to remove noise and Archaea and Vitamin B12 Bacteria was quantified as the area positive for ARC915 or MX825 (but not EUB) and EUB (but not ARC915 or MX825), respectively. The given values are average percentages of Archaea of the total area with values from 90 confocal images. The standard deviations are given as error bars. Figure 10 Distribution of Archaea . The proportion of the total number of confocal images for different intervals of Archaea abundance in triplicate samples from the aeration tank. Figure 11 FISH images with probes for Bacteria , Archaea and Methanosaeta .