The stable oxygen isotope compositions of soil phosphate (δ(18)O(p)) were suggested recently to be a tracer of phosphorus cycling in soils and plants. Here we present a survey of bioavailable (resin-extractable or resin-P) inorganic phosphate δ(18)O(p) across natural and experimental rainfall gradients, and across soil formed on sedimentary and igneous bedrock. In addition, we analyzed the soil...

In previous communications by the authors (1935) data were presented on the effect of some electrolytes, and of ethanol, upon the evolution of carbon dioxide from glucose by yeast aymin. The electrolytes, in appropriate concentrations, stimulate the rate of evolution of the gas. The zymin is very sensitive to ethanol. The addition of phosphate does not decrease the sensitivity toward ethanol, w...

to transport Pi according to the dietary Pi: TRPt was always higher, for a given [Pt]P1, in the animals fed low than in those fed higher Pi diets. This diet-induced modification also occurred in the absence of thyroparathyroid glands, in the presence of the same calcemia and urinary pH, and during marked extracellular volume expansion. A time-course study in rats TPTX both before and during the...

The sea urchin Lytechinus variegatus can survive chronic exposure to sodium phosphate (inorganic phosphate) concentrations as high as 3.2 mg L-1, and triethyl phosphate (organic phosphate) concentrations of 1000 mg L-1. However, chronic exposure to low (0.8 mg L-1 inorganic and 10 mg L-1 organic phosphate), medium (1.6 mg L-1 inorganic and 100 mg L-1 organic phosphate) or high (3.2 mg L-1 inorg...

background and objectives: azotobacter is a diazotroph bacterium reported to possess various plant growth-promoting characteristics.the aim of this study was to isolate azotobacter strains capable of fixing nitrogen and effectively hydrolyzing both organic and inorganic pi compounds. materials and methods: in this study, soil samples collected from a diverse range of slightly alkaline soil type...

Native solium and potassium adenosine triphosphatase from guinea pig kidney accepted a phosphate group from radioactive inorganic phosphate to form an acyl phosphate bond at the active site in the presence or absence of sodium ion. Magnesium ion was always required. In the presence of sodium ion and absence of adenosine triphosphate, there was no phosphorylation by inorganic phosphate. Addition...

Oxygen free N20-saturated aqueous solutions of D-fructose-1-phosphate and Dfructose-6-phosphate were y-irradiated. Inorganic phosphate and phosphate free sugars (containing four to six carbon atoms) were identified and their G-values measured. D-Fructose-1-phosphate yields (G-values in parentheses) inorganic phosphate (1.6), hexos-2-ulose (0.12), 6-deoxy-2,5-hexodiulose (0.16), tetrulose (0.05)...

Guard cells, epidermal cells, palisade parenchyma cells, and spongy parenchyma cells of Vicia faba L. leaflet were analyzed for inorganic phosphate and phosphorus. On a molar basis, cells in the epidermal layer contained about 15-fold more inorganic phosphate than mesophyll cells did. Although a metabolic role for this asymmetric distribution cannot be defined unequivocally, we note that high e...

Colorimetric procedures for the determination of phosphate utilizing the stable yellow color which is developed when an excess of molybdate is added to an acidified solution of orthophosphate and vanadate have been described.2'8 Other workers have developed methods whereby inorganic phosphate and the activity of phosphatases may be estimated in blood serum.1"'5 Although cytochemical techniques ...

In a previous paper (1) evidence was given to show that inorganic phosphate is esterified when succinate is incubated aerobically with cell-free extracts of Escherichia coli in the presence of inorganic phosphate. Based upon residual succinate determinations and upon the theoretical oxygen uptake for oxidation to fumarate, the data have been interpreted to mean that phosphorylation of inorganic...