%0 Journal Article %A Su, Jun-feng %A Zhang, Kai %A Huang, Ting-lin %A Wen, Gang %A Guo, Lin %A Yang, Shao-fei %T Heterotrophic nitrification and aerobic denitrification at low nutrient conditions by a newly isolated bacterium, Acinetobacter sp. SYF26 %D 2015 %J Microbiology, %V 161 %N 4 %P 829-837 %@ 1465-2080 %R https://doi.org/10.1099/mic.0.000047 %I Microbiology Society, %X A new strain, named SYF26, was isolated from the Hei He oligotrophic drinking-water reservoir in China. Based on its phenotypic and phylogenetic characteristics, the isolate was identified as a species of genus Acinetobacter. Strain SYF26 was able to grow at low NH4 +-N concentrations (5.46 mg l−1), and the nitrification rate was 0.064 mg NH4 +-N l−1 h−1. Low accumulation of nitrate and nitrite was observed throughout the ammonium removal experiment. Strain SYF26 reduced NO3 −-N or NO2 −-N. Nitrite reductase and periplasmic nitrate reductase were detectable. The putative nitrogen removal process carried out by the strain SYF26 is as follows: NH4 +→NH2OH→NO2 −→NO3 −, then NO3 −→NO2 −→N2. Response surface methodology analysis demonstrated that the maximum removal of ammonium occurred under the following conditions: NH4 +-N concentration of 22.05 mg l−1, C/N ratio of 4.31, initial pH of 7.78 and temperature of 29.73 °C, where initial pH and temperature had the largest influence on ammonium removal. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.000047