%0 Journal Article %A Loveless, J. E. %A Painter, H. A. %T The Influence of Metal Ion Concentrations and pH Value on the Growth of a Nitrosomonas Strain Isolated from Activated Sludge %D 1968 %J Microbiology, %V 52 %N 1 %P 1-14 %@ 1465-2080 %R https://doi.org/10.1099/00221287-52-1-1 %I Microbiology Society, %X SUMMARY: A strain of Nitrosomonas europaea was isolated from activated-sludge effluent by a dilution method which readily demonstrated the presence of contaminating heterotrophs and yielded a high proportion of tubes containing pure cultures of ammonia-oxidizing bacteria. Copper, sodium, calcium and magnesium stimulated growth of pure cultures, and effects of deficiencies of these metals were demonstrated. Ethylenediaminetetra-acetic acid improved growth in the basal medium, and abolished the toxic effect of added copper; it was, however, inhibitory at low calcium concentrations. The effect of pH value on the growth of N. europaea appeared to be dependent on the metal ion content of the medium although the optimum pH value was always between 7.5 and 8. The growth rate constant in pure culture was similar to that previously observed for nitrification in Thames water, but double that previously observed for nitrification of sewage by activated sludge. The Michaelis constants for ammonia and oxygen were similar to those found for nitrification in activated sludge. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-52-1-1