‘Candidatus Halomonas phosphatis’, a novel polyphosphate-accumulating organism in full-scale enhanced biological phosphorus removal plants
Article first published online: 25 JUL 2012
© 2012 Society for Applied Microbiology and Blackwell Publishing Ltd
Thematic issue: Sulfur Metabolism
Volume 14, Issue 10, pages 2826–2837, October 2012
How to Cite
Nguyen, H. T. T., Nielsen, J. L. and Nielsen, P. H. (2012), ‘Candidatus Halomonas phosphatis’, a novel polyphosphate-accumulating organism in full-scale enhanced biological phosphorus removal plants. Environmental Microbiology, 14: 2826–2837. doi: 10.1111/j.1462-2920.2012.02826.x
- Issue published online: 3 OCT 2012
- Article first published online: 25 JUL 2012
- Accepted manuscript online: 2 JUL 2012 08:13AM EST
- Received 16 July, 2011; revised 12 June, 2012; accepted 20 June, 2012.
Microautoradiography combined with fluorescence in situ hybridization (MAR-FISH) was used to screen for potential polyphosphate-accumulating organisms (PAOs) in full-scale enhanced biological phosphorus removal (EBPR) plants. Clone library analyses and application of MAR-FISH using newly designed probes revealed that small rods related to uncultured Halomonas within the gammaproteobacterial family Halomonadaceae were actively involved in uptake of orthophosphate. Although deeply branched in the Gammaproteobacteria, they were not targeted by the gammaproteobacterial probe (GAM42a). A part of them were also not targeted with the general bacterial probes (EUBmix). They could take up short-chain fatty acids (e.g. acetate and propionate) and ethanol under both anaerobic and aerobic conditions. Polyhydroxyalkanoate storage was observed under anaerobic conditions. There was no indication of a denitrifying capability. A survey of the occurrence of these Halomonas-PAOs in 23 full-scale EBPR plants revealed that they made up 0.5–5.7% of all bacteria in the plants, and were often in higher abundance than the well-described PAOs ‘Candidatus Accumulibacter phosphatis’. This indicates a potentially important role for these uncultured Halomonas bacteria in the EBPR process in full-scale plants and we propose to name them ‘Candidatus Halomonas phosphatis’.