preview

Ntspa 662 Torque

Decent Essays
Open Document

FISH analysis showed that the new extraction method was successful for four out of seven probes used on the sludge samples. The general probe EUB 338 showed a high density of bacteria in the seeding sludge and highly reduced densities after 24 and 28 days of operation, though still some patches with high bacterial density could be detected. In the samples from days 24 and 28 cloudlike structures were observed in all wells including negative controls, which showed high light intensity. These structures coincided with reduced hybridization ability of the EUB 338 probe (cf. figure 14 G-L) Whether the background of these structures was too high, the probe directly bound to the substances, which caused these structures or the hybridizing or fluorescent ability of the …show more content…

With NIT 3 probes hybridized bacteria could not be detected, thus either hybridization was unsuccessful or nitrate reducing activity by the NIT 3 gene was not present in the samples. Showing fewer artifacts, the Ntspa 662 probe showed no positive hybridization. Ntspa 662 is specific for the genus Nitrospira, which is known to conduct nitrite oxidation. For the BS 820 probe, which is specific for Candidatus Scalindua wagneri and C. S. sorokinii, no hybridization to bacteria was found, while for the more general probe Sca 1309 just one very small colony of Candidatus Scalindua specimen could be detected (figure 15, J - L) and a very high abundance of anammox bacteria of the genera Kuenia stuttgardiensis or Brocadia anammoxidans was verified using AMX 820 probe, especially in the seeding sludge samples. Thus the majority of anammox bacteria in the seeding sludge are not of the genus Candidatus Scalindua. Besides the positive FISH results, the shape of bacteria hybridized with AMX 820 was similar to what was initially seen with DAPI. Fluorescence reveals ring and sickle shapes (cf. figure

Get Access