METABOLISM OF MICROORGANISMS RESPONSIBLE FOR ENHANCED BIOLOGICAL PHOSPHORUS REMOVAL FROM WASTE-WATER - USE OF DYNAMIC ENRICHMENT CULTURES

The removal of phosphorus from wastewater is already widely applied. I n many cases use is made of micro organisms capable of accumulating ph osphorus as polyphosphate inside the cell. The main characteristic pro viding the competitive advantage to these polyphosphate accumulating b acteria is the capability to use polyphosphate, in the absence of exte rnal electron accepters, as energy source for the uptake and storage o f acetic acid in the form of polyhydroxybutyrate (PHB). The reduction equivalents for the formation of PHB are derived from the conversion o f glycogen to PHB. Despite the widespread use and study of enhanced bi ological phosphorus removal no pure culture, having the above mentione d characteristics, has been isolated yet. All ecophysiological studies on these type of cultures have therefore been performed by enrichment cultures. This paper reviews the research on these type of organisms, and shows that it is possible to understand a complex microbial proce ss on a metabolic level, both stoichiometrically and kinetically, with out the availability of a pure culture.