title: Measurement and interpretation of microbial adenosine tri-phosphate (ATP) in aquatic environments.
abstract: There is a widespread need for cultivation-free methods to quantify viability of natural microbial communities in aquatic environments. Adenosine tri-phosphate (ATP) is the energy currency of all living cells, and therefore a useful indicator of viability. A luminescence-based ATP kit/protocol was optimised in order to detect ATP concentrations as low as 0.0001 nM with a standard deviation of <5%. Using this method, more than 100 water samples from a variety of aquatic environments (drinking water, groundwater, bottled water, river water, lake water and wastewater effluent) were analysed for extracellular ATP and microbial ATP in comparison with flow-cytometric (FCM) parameters. Microbial ATP concentrations ranged between 3% and 97% of total ATP concentrations, and correlated well (R(2)=0.8) with the concentrations of intact microbial cells (after staining with propidium iodide). From this correlation, we calculated an average ATP-per-cell value of 1.75x10(-10)nmol/cell. An even better correlation (R(2)=0.88) was observed between intact biovolume (derived from FCM scatter data) and microbial ATP concentrations, and an average ATP-per-biovolume value of 2.95x10(-9)nmol/microm(3) was calculated. These results support the use of ATP analysis for both routine monitoring and research purposes, and contribute towards a better interpretation of ATP data.
authors.affiliation: Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600 Dübendorf, Switzerland. frederik.hammes@eawag.ch
authors.forename: Frederik
authors.initials: F
authors.lastname: Hammes
authors.forename: Felix
authors.initials: F
authors.lastname: Goldschmidt
authors.forename: Marius
authors.initials: M
authors.lastname: Vital
authors.forename: Yingying
authors.initials: Y
authors.lastname: Wang
authors.forename: Thomas
authors.initials: T
authors.lastname: Egli
mesh_terms: D000255:Adenosine Triphosphate / Q000032:analysis*; D001419:Bacteria / Q000166:cytology / Q000378:metabolism*; D002138:Calibration; D004784:Environmental Monitoring / Q000379:methods*; D005110:Extracellular Space / Q000378:metabolism; D005434:Flow Cytometry; D014871:Water Microbiology
chemical_list: D000255:Adenosine Triphosphate