Our previous work demonstrated substantial accumulation of allantoate in leaf tissue of nodulated soybeans (Glycine max L. Merr., cv Williams) in response to nitrogen fertilization. Research was continued to determine the effect of nitrate and asparagine on ureide assimilation in soybean leaves. Stem infusion of asparagine into ureide-transporting soybeans resulted in a significant increase in ...

The level of asparagine synthetase is low in 10-mm root tips from corn seedings (Zea mays W64 x W182F) but relatively high in mature root sections taken 20 to 35 mm from the tip. When root tips are excised there is a marked increase in asparagine synthetase over a 5-hour period. In mature root sections, on the other hand, the asparagine synthetase activity declines over the same 5-hour period. ...

endo-derived nitric oxide (no) is synthesized from l-arginine by endothelium nitric oxide synthase (enos). since reduced no synthesis has been implicated in the development of coronary atherosclerosis; we hypothesized that polymorphisms of nos gene might be associated with increased susceptibility to this disorder and coronary artery disease (cad). we studied the 27 base pair tandem repeat poly...

Asparagine biosynthesis in soybean (Glycine max [L.] Merr.) nodules has been difficult to demonstrate due to the poor conversion of suspected immediate precursors to asparagine and the instability of the key enzyme asparagine synthetase. The present study was designed to explore the effects of two ammonium assimilation inhibitors on the metabolism of (14)CO(2) to [(14)C]asparagine and to demons...

Legumes obtain a substantial portion of their nitrogen (N) from symbiotic N2 fixation in root nodules. The glutamine synthetase (GS, EC 6.3.1.2)/glutamate synthase (GOGAT) cycle is responsible for the initial N assimilation. This report describes the analysis of a transgenic alfalfa (Medicago sativa L.) line containing an antisense NADH-GOGAT (EC 1.4.1.14) under the control of the nodule-enhanc...

Cyanide disappears from a medium supporting actively growing cells of Bacillus megaterium, a bacterium isolated from a cyanide enrichment medium containing Fargo clay soil. Whole cells of this organism convert K14CN to asparagine-*4C, aspartic acid-14C and 14C02. Besides cyanide, serine l4C and /3-cyanoalanine-14C are effectively converted by whole cells of this organism to asparagine-14C. An a...