The intermediate role of hydroxylamine in nitrate assimilation has been suggested by observations that different organisms form ammonia from hydroxylamine in vivo, and that hydroxylamine occurs in nutrient media and cells. In further support are recent investigations describing enzymatic preparations which catalyze the reduction of hydroxylamine to ammonia. Taniguchi et al. (J. Biochem. (Japan)...

In the crystal structure of the title compound, (C(3)H(5)N(2))(NH(4))[Cr(2)O(7)], the anions and cations are linked through N-H⋯O hydrogen bonds, resulting in a three-dimensional structure which contains three kinds of layers parallel to (001). One layer contains imidazole cations, the other two layers the ammonium cations and dichromate anions. The dichromate anion has an eclipsed conformation...

Excretion patterns and rates of ammonium perfluorohexanoate (APFHx) after administration of a single and multiple (14 days) oral dose(s) at 50 mg/kg to male and female mice and rats were examined. The test substance was [(14)C]-labeled APFHx. After a single oral administration, total excretion was rapid, with mean recoveries of over 90% of the dose at 24 hours after administration, irrespective...

Lambir Hills National Park in Malaysian Borneo is composed of dipterocarp tree species which specialize on different soil types. Although the mechanisms contributing to this distribution of tree species are unknown, one hypothesis is that tree species at Lambir differ in their preferences for different nitrogen forms. In this study we investigated (1) whether clay soil and sandy loam soil types...

Proteins of the conserved Mep-Amt-Rh family, including mammalian Rhesus factors, mediate transmembrane ammonium transport. Ammonium is an important nitrogen source for the biosynthesis of amino acids but is also a metabolic waste product. Its disposal in urine plays a critical role in the regulation of the acid/base homeostasis, especially with an acid diet, a trait of Western countries. Ammoni...

We have examined nutritional factors influencing conjugal transfer of the two nonsymbiotic large plasmids, pRmeGR4a and pRmeGR4b, of Rhizobium meliloti GR4. To monitor transfer, each plasmid was tagged with a different antibiotic resistance marker. Transfer of plasmid pRmeGR4b was dependent upon the presence of plasmid pRmeGR4a on the same donor cell. Transconjugants for pRmeGR4b were obtained ...

In the title molecular salt, C(10)H(15)NH(3) (+)·C(7)H(5)O(2) (-), both carboxyl O atoms act as acceptors for strong N-H⋯O inter-molecular hydrogen-bond inter-actions with the ammonium group in the cation, generating infinite chains along the b axis. A weak C-H⋯π inter-action is also present.

In the title compound, C(10)H(18)N(+)·C(2)H(3)O(2) (-), the ammonium H atoms of the cation are linked to three acetate anions via N-H⋯O hydrogen bonds, forming a chain structure extending along the b axis.

The cations and anions of the title salt, NH(4) (+)·C(12)H(27)O(3)SSi(-), are linked by N-H⋯S and N-H⋯O hydrogen bonds into a linear chain that runs along the a axis of the monoclinic unit cell. The asymmetric unit contains two cations and two anions.

The title compound, NH(4) (+)·C(6)H(10)NS(2) (-), is composed of an ammonium cation and a piperidine-1-carbodithio-ate anion which exhibits positional disorder. The atoms of the ring have a structural disorder and they are divided into two sites, with occupancy factors of 0.584 and 0.426.. In the crystal, the cation and anion are linked by N-H⋯S hydrogen bonds to form an infinite two-dimensiona...