We measured the uptake rate of molybdatc and related kinetic parameters for nine taxa of cyanobacteria and for the natural phytoplankton communities of six freshwater lakes containing planktonic Nz-fixing cyanobacteria. Molybdate uptake followed saturation kinetics and was competitively inhibited by both tungstate and sulfate. Tungstate inhibited molybdate uptake in a nearly mole-for-mole fashi...

When Escherichia coli was grown in the presence of tungstate, inactive forms of two molybdoenzymes, nitrate reductase and formate dehydrogenase, accumulated and were converted to their active forms upon incubation of cell suspensions with molybdate and chloramphenicol. The conversion to the active enzymes did not occur in cell extracts. When incubated with [(99)Mo]molybdate and chloramphenicol,...

Clearly there are differences in the observed reactivities of the "heavily oxidized" surfaces of Mo(1 I0) prepared by Queeney et al. [1] and those prepared by us [2]. We note, however, that our study is in agreement with, and provides fresh insight into, the chemistry of high surface-area (HSA), "real-world" molybdate catalysts. The 3D oxide prepared by us (i) does not produce methyl radicals, ...

1. [35S]sulphate was used to measure the apparent turnover of sulphate, sulphide and microbial-protein-S in the rumen contents of four sheep that were intraruminally infused with 10 g sodium sulphate/d alone, or together with 126 mg sodium molybdate (50 mg molybdenum). 2. Infusion of molybdate increased the concentration of sulphate in rumen fluid from 2.2 to 7.2 mug S/ml and decreased the rate...

Anabaena variabilis fixes nitrogen under aerobic growth conditions in differentiated cells called heterocysts using either a Mo nitrogenase or a V nitrogenase. The nifH1 gene, which encodes the dinitrogenase reductase of the Mo nitrogenase that is expressed only in heterocysts, is cotranscribed with nifD1 and nifK1, which together encode the Mo dinitrogenase. These genes were expressed in the p...

Nickel molybdate (NiMoO₄) nanoparticles were synthesized via calcination of an oxalate complex in static air at 500 °C. The oxalate complex was analyzed by thermal gravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR). The as-synthesized nickel molybdate was characterized by Brunauer-Emmett-Teller technique (BET), X-ray diffraction (XRD), and transmission electron micros...

Thiobacillus novellus shows a maximum induction of sulfite oxidase activity and a maximum growth rate as a result of supplementing the autotrophic growth medium with 4.0 microM ammonium molybdate. Cells grown in the presence of molybdate showed approximately 10-fold increases in the amount of enzyme-associated molybdenum and in the sulfite-to-cytochrome c and sulfite-to-ferricyanide reductase a...

In this work, several nano/microscale structures of ZnO including nanospindles, microbundles, microrods, and nanoflowers have been prepared via a facile template and surfactant-free hydrothermal method mediated with ammonium molybdate. It is found that the morphology of ZnO could be readily tailored by simple variation of the concentration of ammonium molybdate. The effects of the concentration...

This study aims to evaluate the benefit of combined administration of sodium molybdate with atorvastatin in management of hyperlipidemia. Hyperlipidemic male Serian golden hamsters were administered either atorvastatin (40 or 80 mg/kg, p.o.) sodium molybdate (100 mg/kg, p.o.) or combination of atorvastatin (40 mg/kg, p.o.) with sodium molybdate (100 mg/kg, p.o.) for 30 consecutive days. Blood l...