Phebe van Langevelde earned her BSc in molecular science and technology from Leiden University Delft of Technology (joint degree) 2017. She completed a master's degree chemistry with specialization energy sustainability at 2020, working on the development catalysts for oxygen reduction reaction, was visiting student Institute Chemical Research Catalonia (ICIQ). Since she is PhD candidate Cataly...

The reduction of nitrate by molecular hydrogen was observed first in Bacterium formicum by Stephenson and Stickland (1931). In this system, the product of the reduction was nitrite, and the theoretical hydrogen uptake occurred only when the endogenous respiration of the cell was suppressed by prior treatment of the cells with toluene (Stickland, 1931). Woods (1938) found that Clostridium perfri...

The effect of nitrate on N(2) fixation and the assimilation of fixed N(2) in legume nodules was investigated by supplying nitrate to well established soybean (Glycine max L. Merr. cv Bragg)-Rhizobium japonicum (strain 3I1b110) symbioses. Three different techniques, acetylene reduction, (15)N(2) fixation and relative abundance of ureides ([ureides/(ureides + nitrate + alpha-amino nitrogen)] x 10...

The respiratory molybdoenzyme nitrate reductase (NarGHI) from Escherichia coli has been studied by protein film voltammetry, with the enzyme adsorbed on a rotating disk pyrolytic graphite edge (PGE) electrode. Catalytic voltammograms for nitrate reduction show a complex wave consisting of two components that vary with pH, nitrate concentration, and the presence of inhibitors. At micromolar leve...

Respiratory ammonification of nitrate is the microbial process that determines the retention of nitrogen in an ecosystem. To date, sulfur-dependent dissimilatory nitrate reduction to ammonium has been demonstrated only with sulfide as an electron donor. We detected a novel pathway that couples the sulfur and nitrogen cycles. Thermophilic anaerobic bacteria Thermosulfurimonas dismutans and Dissu...

Four desoxo Mo(iv) bis(dithiolene) complexes, [Et(4)N][Mo(IV)(PPh(3))(SC(6)H(4)-p-Me)(mnt)(2)] () (mnt = maleonitrile dithiolate), [PNP][Mo(IV)(PPh(3))(SC(6)H(4)-o-COOH)(mnt)(2)].CH(3)CN.(i)PrOH () (PNP is [Ph(3)PNPPh(3)](+)), [Et(4)N][Mo(IV)(PPh(3))(NCS)(mnt)(2)] () and [Et(4)N](2)[Mo(IV)(NCS)(2)(mnt)(2)] () are synthesized and characterized structurally. Complexes and are found to release the...

The kinetics of denitrification and the causes of nitrite and nitrous oxide accumulation were examined in resting cell suspensions of three denitrifiers. An Alcaligenes species and a Pseudomonas fluorescens isolate characteristically accumulated nitrite when reducing nitrate; a Flavobacterium isolate did not. Nitrate did not inhibit nitrite reduction in cultures grown with tungstate to prevent ...

The effect of nitrogen form (NH(4)-N, NH(4)-N + NO(3) (-), NO(3) (-)) on nitrate reductase activity in roots and shoots of maize (Zea mays L. cv INRA 508) seedlings was studied. Nitrate reductase activity in leaves was consistent with the well known fact that NO(3) (-) increases, and NH(4) (+) and amide-N decrease, nitrate reductase activity. Nitrate reductase activity in the roots, however, co...

16 Groundwaters at nuclear sites are often characterised by low pH and high nitrate 17 concentrations (10-100 mM). These conditions are challenging for bioremediation, often 18 inhibiting microbial Fe(III)-reduction that can limit radionuclide migration. Here, sediment 19 microcosms representative of the UK Sellafield site were used to study the influence of 20 variable pH and nitrate concentra...