Hydroxylamine (NH(2)OH) is an unstable compound at room temperature, and it has been involved in two tragic industrial incidents. Although experimental studies have been carried out to study the thermal stability of hydroxylamine, the detailed decomposition mechanism is still in debate. In this work, several density functional and ab initio methods were used in conjunction with several basis se...

Anaerobic ammonium oxidation is a recent addition to the microbial nitrogen cycle, and its metabolic pathway, including the production and conversion of its intermediate hydrazine, is not well understood. Therefore, the effect of hydroxylamine addition on the hydrazine metabolism of anaerobic ammonium-oxidizing (anammox) bacteria was studied both experimentally and by mathematical modeling. It ...

Soil ingestion by children is an important pathway in assessing public health risks associated with exposure to arsenic-contaminated soils. Soil chemical methods are available to extract various pools of soil arsenic, but their ability to measure bioavailable arsenic from soil ingestion is unknown. Arsenic extracted by five commonly used soil extractants was compared with bioavailable arsenic m...

The chemoautotrophic bacterium, Nitrosomonas europaea, derives its energy from the oxidation of ammonia to nitrite. Several investigators have noted that the ability to oxidize ammonia is entirely lost upon rupture of the Nitrosomonas cell, and that, although cell-free preparations retain a small fraction of the hydroxylamine-oxidizing activity, only 30 to 70% of the total hydroxylamine that is...

N-(2-methoxyphenyl)hydroxylamine is a human metabolite of the industrial and environmental pollutants and bladder carcinogens 2-methoxyaniline (o-anisidine) and 2-methoxynitrobenzene (o-nitroanisole). Here, we investigated the ability of hepatic microsomes from rat and rabbit to metabolize this reactive compound. We found that N-(2-methoxyphenyl)hydroxylamine is metabolized by microsomes of bot...

In spite of its physiological importance acetylcholine has been determinable chemically only after isolation by time-consuming procedures. Of necessity workers in this field have resorted to pharmacological bioassays whose specificity seems open to doubt. The finding that choline is readily acetylated by the action of a coenzyme-linked enzyme system in which adenosine triphosphate serves as an ...

The synthesis of y-glutamylhydroxamic acid from glutamine and hydroxylamine is catalyzed by glutamine synthetase in the presence of adenosine diphosphate, inorganic phosphate, and magnesium ions (l), and also by other enzyme preparations (2,3) that do not exhibit a requirement for nucleotides or metal ions. The synthesis of y-glutamylhydroxamic acid from glutamic acid and hydroxylamine that is ...