RT Journal Article SR Electronic(1) A1 Caskey, William H. A1 Tiedje, James M.YR 1980 T1 The Reduction of Nitrate to Ammonium by a Clostridium sp. Isolated from Soil JF Microbiology, VO 119 IS 1 SP 217 OP 223 DO https://doi.org/10.1099/00221287-119-1-217 PB Microbiology Society, SN 1465-2080, AB Cultures of Clostridium KDHS2 reduced 15NO3 − to 15NH4 + with a concurrent increase in molar growth yield of 157% compared with fermentatively grown bacteria. The bacteria exhibited a K 8 (NO3 −) of 0·5 mm and reduced NO3-maximally at a rate of 01 mol h−1 (mg dry wt)−1. A partially purified nitrate reductase was obtained whichhad a K m (NO3-) of 0·15 mm. The reduction of 13NO3 − to 13NH4 + by resting bacteria was not inhibited by NH4 +, glutamate, glutamine, methionine sulphoximine or azaserine. Glutamine synthetase affected neither the synthesis nor the activity of the NO3 −-reducing enzymes. The results are consistent with the hypothesis that NO3 − reduction to NH4 + in this Clostridium sp. is dissimilative. SO3 2−, but not SO4 2−, inhibited the reaction, apparently at the level of NO2 − reduction., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-119-1-217