IWA Publishing
 IWA Publishing Journals   Subscriptions   Authors   Users   Librarians   FAQs 

Water Science & Technology Vol 46 No 1-2 pp 155–162 © IWA Publishing 2002

Polyphosphate kinase genes from activated sludge carrying out enhanced biological phosphorus removal

K.D. McMahon*, D. Jenkins** and J.D. Keasling***

*Department of Civil and Environmental Engineering, University of California at Berkeley, Berkeley, CA 94720-1710, USA
**Department of Civil and Environmental Engineering, University of California at Berkeley, Berkeley, CA 94720-1710, USA
***Department of Chemical Engineering, University of California at Berkeley, Berkeley, CA 94720-1710, USA


ABSTRACT
The community structure and metabolic function of activated sludge carrying out enhanced biological phosphorus removal have been investigated. Laboratory-scale sequencing batch reactors were operated at several influent COD/P ratios to obtain sludges with a range of phosphorus contents. Molecular microbiological techniques based on small subunit ribosomal RNA were used to characterize the community structure of these sludges. The dominant polyphosphate accumulating organism was a close relative of Rhodocyclus tenuis, a member of the ? subclass of the Proteobacteria. Fragments of genes coding for polyphosphate kinase (PPK), thought to be responsible for polyphosphate accumulation, were retrieved from one of the sludges. The relative abundance of PPK gene copies in genomic DNA extracted from sludges was determined to confirm that at least one of the PPK gene sequences was derived from the dominant polyphosphate accumulating organism.

Full article (PDF Format)


eProduct: Buy this article for £24.00 (IWA MEMBER PRICE: £18.00)
All prices include VAT. For customers where VAT should not be applied, the VAT amount will be removed upon payment