title: Luxury uptake of phosphorus by sediment bacteria.
abstract: This note reports the results of experiments aimed at confirming the luxury uptake of phosphorus (P) by sediment bacteria as polyphosphate (Poly-P). Aerobic suspensions of sediments from two different sites were spiked with 1 mg P/L as orthophosphate and augmented with acetate (a fermentation product) or glucose. The orthophosphate was rapidly taken up over a period of a few hours. When these aerobic uptake experiments were made anaerobic and additional organic carbon added, only the acetate-amended sediment released a significant amount of the added phosphorus. It was hypothesised that during the aerobic stage, and with the addition of acetate, some of the phosphorus was accumulated as Poly-P by sediment microorganisms, which was released during the subsequent anaerobic stage (provided acetate was still present). Two lines of evidence--transmission electron microscope analysis of sediment bacteria and 31P-NMR analysis of sediment extracts--are presented to support the hypothesis that a portion of the phosphorus taken up during the aerobic experiments was stored as Poly-P.
authors.affiliation: CRC for Freshwater Ecology, Water Studies Centre & Department of Chemistry, Monash University, Melbourne, Australia.
authors.forename: Aazam
authors.initials: A
authors.lastname: Khoshmanesh
authors.forename: Barry T
authors.initials: BT
authors.lastname: Hart
authors.forename: Anabelle
authors.initials: A
authors.lastname: Duncan
authors.forename: Ron
authors.initials: R
authors.lastname: Beckett
mesh_terms: D001419:Bacteria; D019015:Geologic Sediments / Q000382:microbiology*; D009682:Magnetic Resonance Spectroscopy; D008854:Microscopy, Electron; D010758:Phosphorus / Q000493:pharmacokinetics*; D011122:Polyphosphates / Q000737:chemistry*
chemical_list: D011122:Polyphosphates; D010758:Phosphorus