Abstract
Two 2, 6-naphthalenedisulfonate (2, 6NDS) degrading bacteria were isolated from the activated sludge of a wastewater treatment plant and designated NDS-1 and NDS-2. Only strain NDS-1 showed a floc-forming ability in such media as synthetic wastewater. Sequence analysis of the partial 16S ribosomal DNA (rDNA) sequence of strain NDS-1 revealed that it is a strain closely related to Pigmentiphaga kullae, which was recently established in the family Alcaligenaceae, and that the sequence was in perfect agreement with that of strain NDS-2. Strain NDS-1 could mineralize 2, 6NDS and 1, 6-naphthalenedisulfonate (1, 6NDS) with sulfate ion release, but showed no assimilating or desulfonating activity on 8 other sulfonated naphthalenes, indicating that it has a very narrow substrate specificity. 2, 6NDS-induced NDS-1 cells exhibited a high oxygen uptake for 2, 6NDS, while non-induced cells showed a very low oxygen uptake, demonstrating that 2, 6NDS oxidation is inducible in strain NDS-1.
