title: Requirement of Acinetobacter junii for magnesium, calcium and potassium ions.
abstract: The goal of this study was to determine the concentrations of Mg, Ca and K ions required for the formation of metabolically active population of phosphate (P)-accumulating bacterium Acinetobacter junii. The availability of Mg, Ca and K originating from natural minerals in the conditions of severe shortage of these cations was tested. In the case of shortage of Mg, Ca and K ions in wastewater the P removal was absent due to the decay of A. junii. In the cases of Mg or K shortage in wastewater the P removal was negligible due to the decay of A. junii, while Ca was not essential for the examined bacterium. The minimal required concentrations of Mg and K in synthetic wastewater were 0.64 mg Mg/mg P and 0.50 mg K/mg P. The natural zeolitized tuffs and bentonite, either in Mg, Ca or K form, successfully replaced the lack of Mg, Ca, K and trace metals in wastewater. The requirement of A. junii for examined cations was in the order: Mg>K>Ca.
authors.affiliation: University of Zagreb, Faculty of Science, Rooseveltov trg 6, 10000 Zagreb, Croatia. jasnah@zg.biol.pmf.hr
authors.forename: Jasna
authors.initials: J
authors.lastname: Hrenovic
authors.forename: Tomislav
authors.initials: T
authors.lastname: Ivankovic
authors.forename: Mirela
authors.initials: M
authors.lastname: Rozic
mesh_terms: D000150:Acinetobacter / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology; D002118:Calcium / Q000378:metabolism*; D018929:Cell Culture Techniques / Q000379:methods; D007477:Ions; D008274:Magnesium / Q000378:metabolism*; D010710:Phosphates / Q000302:isolation & purification / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism*; D012722:Sewage / Q000382:microbiology*; D014871:Water Microbiology; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D007477:Ions; D010710:Phosphates; D012722:Sewage; D014874:Water Pollutants, Chemical; D008274:Magnesium; D011188:Potassium; D002118:Calcium