Acid-soluble Organic Phosphates Research Articles

Fractionation of phosphate in sediments of four representative mangrove stages (French Guiana)

Phosphate was fractionated in Guianese mangrove sediments. Fe(OOH)≈P was extracted using a Ca-EDTA + Na-dithionite solution buffered at pH 8. CaCO3≈P was extracted using Na2-EDTA solution at pH 4.5. Next, Acid Soluble Organic Phosphate (ASOP) was extracted by H2SO4 0.5 N. Finally, Residual Organic Phosphate (ROP) was digested with H2SO4 + H2O2. Four representative mangrove stages have been studied: sea edge pioneer mangroves, mature coastal mangroves, mixed riverine mangroves, and declining to dead mangroves. The sum of the P-fractions varied between 638 to 804 μg g-1 in pioneer and mixed mangroves respectively. In all the stages, the percentage of inorganic phosphate was larger than 50% of the total P. Fe(OOH)≈P varied between 221 (pioneer mangrove) to 426 μg g-1 (dead mangrove). CaCO3≈P varied between 75 to 102 μg g-1 in mixed, dead or mature mangroves and attained 125 μg g-1 in pioneer mangrove. The sum of the concentrations of organic phosphate (ASOP + ROP) increased markedly from the dead mangrove (189 μg g-1) to the mixed mangrove (380 μg g-1). Guianese mangroves, are relatively rich in total phosphate, possibly because they are narrowly related to the 'Amazon dispersal system′. Each mangrove stage can be characterised by a prevailing form of phosphate. The concentrations of these different forms were ascribed to the marked relations with the seawater which controls import or export of suspended matters and to the wave action which controls the resuspension of the sediments and subsequently exchange of phosphate between the suspended matter and the water column.

Changes in sediment phosphate composition of seasonal ponds during filling

Most ponds from the Donana National Park are shallow temporary freshwater bodies on eolian sands. The total phosphate concentration and the fractional P-composition of the sediments from two small ponds were studied before and inmediately after they were filled (autumn, 1996). Total phosphorus concentration was measured in 2 different size fractions: 2–0.1 mm (coarse) and <0.1 mm (fine). In both ponds, the total phosphorus concentration of the fine sediment increased by 20% at the beginning of the filling period, whereas 5 weeks later it did not increase further. The percentage of organic matter of the fine sediment was relatively high (between 13–18%) and did not change significantly during filling. The concentration of sediment total iron and Fe(OOH) increased significantly in both ponds during filling. The sequential P fractionation of the fine sediment included, besides the determination of two inorganic fractions (Ca-bound P and Fe-bound P), an organic-P fraction extracted with acid, another extracted with alkali, two organic-P fractios from the Ca-EDTA/dithionite and the Na2-EDTA extracts which contained high concentrations of humic substances. The pond sediments were rich in organic P compounds as the sum of all organic-P fractions ranged between 267 and 320 μg g-1 (68% and 79% of the sum of all fractions). Significant changes (P<0.01) in the fractional P-composition of sediments were found after filling. Acid soluble organic phosphate increased about 30% in both ponds. Iron-bound phosphate increased significantly (about 40%) only in the pond where a higher concentration of Fe(OOH) was measured after filling. An adsorption experiment was carried out for each sediment to simulate P input during filling. Both the iron-bound phosphate and Ca-bound P increased significantly (P<0.01) suggesting that these two fractions were involved in the P-adsorption during the laboratory experiment.

The impact of desiccation of a freshwater marsh (Garcines Nord, Camargue, France) on sediment-water-vegetation interactions

The impact of desiccation on a marsh sediment was studied both in the laboratory and in the field. Changes in the sediment chemistry of a homogenized sediment suspension during desiccation were studied in the laboratory. FeS was oxidized completely. A considerable mineralization of organic phosphate took place, from both the acid soluble organic phosphate fraction and from the residual organic phosphate fraction, but no significant mineralization of organic matter was observed. The o-P formed during the mineralization was recovered partly in the Fe(OOH) ≈P fraction and partly in the CaC3≈P fraction. An upward flux was found. During spring and summer 1990 the water inlet to a shallow permanent freshwater marsh with a surface of about 1.5 hectares was blocked, in order to desiccate the marsh by evaporation. The sediments initially consisted of a black anoxic organic top layer and a less organic anoxic gray layer. During the desiccation of the sediment a brown oxic surface layer was formed from the black layer and an increase of pH and Eh occurred. Subsequent rainfall made the Eh increase further but caused a decrease in pH indicating an increase in bacterial activity. A progressive oxidation of FeS was observed. An increase in Tot-P in the surface layer and a decrease in the gray and the black layer of the sediment occurred, probably due to a capillary upward flux. A mineralization of organic matter was observed in the two deeper layers. In the upper brown layer this mineralization was less evident, probably because it has been masked by the capillary movement. A net C loss of 40% was calculated to have occurred in the layer 0–40 cm. In the deeper layers a decrease in Tot-N was observed, whereas no important increase occurred in the top layer. Over a sediment layer of 40 cm a N loss of 50% was calculated. C- and N losses occurred simultaneously, suggesting the importance of mineralization as a source of inorg-N for denitrification. The chemical and physical changes in the sediment during desiccation affected layers down to 40 cm. This means that not only the top layer of a sediment but also deeper layers are active in systems of which part of the sediment dries occasionally. Fractionation of the surface sediment phosphate showed an increase of Fe(OOH) ≈ P in the top layer due to the oxidation of FeS to Fe(OOH), enlarging the P-adsorption capacity of the sediment. A mineralization of about 50% of acid soluble organic phosphate occurred. After rainfall, a net increase in residual organic phosphate occured presumably due to an increase of bacterial activity. Drying may therefore be utilized as a tool, in wetland management, to eliminate organic nitrogen and carbon from the sediment. In rice culture, it may be used to make part of the organic nitrogen available to the rice.

The impact of desiccation of a freshwater marsh (Garcines Nord, Camargue, France) on sediment-water-vegetation interactions

Changes in the fractional P-composition and the P-adsorption capacity of the Garcines (Camargue, France) a freshwater marsh sediment were studied. Desiccation was found to cause considerable shifts in the fractional composition of the sediment layers studied. In the surface layer an increase in Fe(OOH)≃P and a slight decrease in CaCO 3 ≃P occurred. A specific mineralization of Acid Soluble Organic Phosphate (ASOP) occurred: about 40% (about 70 μg g -1 ) of Acid Soluble Organic Phosphate was mineralized in the surface sediment and about 60% (about 200 μg g -1 ) in a deeper layer

On the presence of organic phosphate in some Camargue sediments: evidence for the importance of phytate

The organic phosphate pool of some Camargue sediments (South of France) was studied, after removal of inorganic phosphate, with Ca-NTA/dithionite (Fe bound phosphate) and Na-EDTA (Ca bound phosphate). The organic phosphate was divided into an acid soluble organic phosphate fraction (ASOP) and a residual organic phosphate fraction (ROP). The extraction of organic matter with 2.0 M NaOH (90 °C) from ROP yielded considerable quantities of Org-P. In this extract the presence of phytate (inositol hexa phosphate) could be demonstrated using phytase to hydrolyse the phytate. Phytate was shown to account for a considerable part of organic phosphate in sediments of freshwater marsh sediments as well as in the sediment of the brackish/salt water lake ‘Etang de Vaccares’. In laboratory experiments phytate was found to precipitate with all poly-valent cations tested. Furthermore, phytate was found to be strongly adsorbed onto Fe(OOH), which may explain its accumulation and its stability in sediments.

Some remarks on the presence of organic phosphates in sediments

This article describes a new method developed to assess the size and nature of the organic phosphate pool. Using sediment suspensions from the Rhone, Garonne and Po rivers, inorganic P compounds, Fe(OOH) and CaCO3 were removed using mild extractants at sediment pH. The residual phosphate was then fractionated into an acid soluble organic phosphate pool and a residual organic phosphate pool by acid hydrolysis (0.5 M H+). Both pools were quantitatively important, accounting for between 16 and 54% and 16 and 51% of total phosphate respectively. Acid hydrolysis was chosen since it yielded a distinct plateau, with high reproducibility, within 30 minutes. This fractionation permits a further study of dynamics and bioavailability of sediment org-P, without interference of Fe(OOH) and CaCO3. In many studies in which changes in the organic pool were examined after extraction of inorganic phosphate, 0.5 M HCl was used to extract apatite bound phosphate. The results presented here show that this is likely to result in a considerable underestimation of the organic phosphate pool.

Änderungen im Phosphat-Stoffwechsel regenerierender Zellen des Lebermooses Riella helicophylla (Bory et Mont.) Mont.

In small thallus fragments with constant cell number (microfragments) of the liverwort Riella helicophylla acid soluble organic phosphate is doubled 48 h after fragment isolation. Nucleic acid phosphate increases 20–30 %, lipid-phosphate increases only slightly, inorganic phosphate diminishes approximately 50%. The additional phosphate is taken from the nutrient solution with growing tendency during the first 24 h. This supply, however, is dispensible, because the microfragments are able to regenerate in distilled water, indeed with delay and reduction. The registered shift of phosphate fractions is mainly caused by interrelationships between regenerating and non-regenerating cells within the fragment. This is revealed by microanalytical analysis of the adaxial and peripheral fragment region. The results show, that inorganic phosphate is enhanced in the regenerating cells, and diminished in the non-regenerating ones. The latter cells apparently serve as phosphate donators. 32 P is transferred quickly between the two cell types, in the isolated fragments in the same manner as in the intact plant. This leads to the conclusion that the phosphate augmentation in regenerating Riella cells is not brought about by new sink characteristics in these cells.

High levels of inosine monophosphate in the erythrocytes of elasmobranchs.

The acid soluble organic phosphates of the erythrocytes of three species of elasmobranchs were assayed by chromatography on Dowex 1 anion exchange columns. Organic phosphates in the peaks eluted from these columns were identified by their ultraviolet absorption spectra and by further chromatography on paper. All three species are unusual amongst the vertebrates in that their erythrocytes contain high levels of inosine monophosphate (IMP). IMP has little effect on the oxygen affinity of the hemoglobins of the two species tested.

The major erythrocytic organic phosphates of the American eel, Anguilla rostrata

1. 1. The major acid-soluble organic phosphates associated with the erythrocytes of eels, Anguilla rostrata, acclimated to fresh and saltwater were determined by ion-exchange chromatography. 2. 2. The major erythrocytic phosphate of the eel is guanosine triphosphate (GTP) † with adenosine triphosphate (ATP) as the second most abundant phosphate compound. 3. 3. Total phosphate concentrations were approximately equal in marine and fresh water eels; marine eels exhibited high GTP: Hb and low ATP : Hb ratios while fresh water eels showed lower GTP : Hb and higher ATP : Hb ratios.

Alkaline phosphatase production of Bacillus subtilis

Abstract Since alkaline phosphate activity increases in sporulation medium during the developmental period, in spite of the presence of inorganic phosphate, the uptake and intracellular concentration of phosphate were measured. While the uptake of inorganic phosphate decreases and the concentration of acid-soluble organic phosphate remains constant, the intracellular concentration of inorganic phosphate increases to about 30 mM after the end of growth. Some compound other than inorganic phosphate must therefore repress alkaline phosphatase. Other experiments showed that addition of glucose delays both the alkaline phosphatase increase and sporulation by about the same time.

Low temperature induced metabolic changes in the shoot meristematic region of Marquillo × Kenya Farmer wheat dwarf 1 plants

Marquillo × Kenya Farmer 1 (Mql × KF 1) wheat plants respond to very short 16° treatment by decreased meristematic activity of the apical meristem and extensive cellular destruction in young leaf and stem tissues. By radiotracer techniques the metabolism of 3H-thymidine, 32P, and 14C-leucine fed to intact shoot tissues of Mql × KF 1 and normal Marquillo (Mql) plants were studied.Immediately after the onset of 16° treatment, the incorporation of both 3H-thymidine and 32P into the DNA of Mql × KF 1 meristematic regions began to decline rapidly although the total uptake of label into the meristematic tissue remained constant. The incorporation of 32P into the RNA, the acid-soluble organic phosphate compounds, and phospholipids of the Mql × KF 1 meristems also declined during the first 24 h and the inorganic phosphate radioactivity increased. After the initial decrease, the proportion of radioactivity in the RNA and acid-soluble organic compounds increased to near control levels. The distribution patterns of both 3H-thymidine and 32P were unchanged in the meristematic region of Mql × KF 1 plants at 26° or Mql plants at 16° or 26°. Protein synthesis in meristematic regions, measured by the incorporation of 14C-leucine, responds to temperature similarly in Mql × KF 1 and Mql plants.The inhibitions of mitosis, phospholipid synthesis, and DNA synthesis were extremely rapid and reversible after short 16° exposures, and are thought to be close to the primary process of temperature lethality of Mql × KF 1 plants. Although it is not known if any of these processes are responsible for the others, it is proposed that the cellular destruction is caused by the inability of cells in the elongating regions to synthesize the phospholipid components of membranes.

Effects of Freeze‐Drying on Permeability and Respiration of Germinating Lily Pollen

AbstractThe germination of lily pollen (Lilium longiflorum cv. Ace) was impaired by freeze‐drying. This loss of viability was associated with a modified pattern of respiration and an increased leakage of soluble carbohydrates, phosphate, and ninhydrin‐positive material into the culture medium. 2,4‐Dinitro‐phenol, (DNP), an uncoupler of oxidative phosphorylation showed a decreased ability to stimulate O2 uptake in freeze‐dried pollen. The altered viability, respiration, and permeability resulted from drying under vacuum and not the initial freezing of the pollen. Mature lily pollen contained approximately 0.3 “Ai phosphate, of which 15 % was inorganic phosphate and about 50 %&gt; was acid soluble organic phosphate of unknown identity.

Maximal elevation of 2,3-diphosphoglycerate concentrations in human erythrocytes: influence on glycolytic metabolism and intracellular pH.

The 2,3-DPG content of human red blood cells can be elevated in vitro to a maximum of 24 μMoles/g by incubating the cells in media containing inosine, pyruvate and inorganic phosphate (=IPP media). The rate of accumulation depends on the extracellular phosphate level. The concentrations of organic phosphate fractions other than 2,3-DPG also increase during the initial phase of incubation in IPP media, but rediminish thereafter. As a consequence of these changes, the total concentration of acid-soluble organic phosphates in the red cells rises from 14 to 55 μMoles P/g red cells. This increase of non-penetrating anions produces a shifting of the Donnan ratio H e +/H i + to lower values and thereby diminishes progressively the intracellular pH of the red cells during incubation in IPP media. The extent of these changes can be calculated on the basis of equations derived by van Slyke. The Donnan induced intracellular acidification causes a gradual impairment of red cell metabolism as the 2,3-DPG concentration increases, thus imposing a selflimitation to the accumulation of 2,3-DPG in the presence of IPP and leading to an inhibition of glucose consumption in IPP-pretreated cells. The findings are discussed with respect to their metabolic and biophysical basis and in view of possible implications for the regulation of red cell metabolism and function.

Nuclear metabolism: I. Nuclear phosphorylation

The ATP utilized in metabolic reactions within the nucleus is produced exclusively in the nucleus by glycolysis and oxidative phosphorylation. When the concentration of ATP per se is measured it was found to decrease after a short period of time probably due to its breakdown by phosphatases or its utilization by synthetic reactions. When a suitable trapping system was employed it was found that the nucleus could sustain a measurable synthesis of ATP for several hours. “ATP energy” can probably be stored in the form of polyphosphates under certain conditions of metabolic inactivity. A number of compounds were found to affect the synthesis of nuclear acid-soluble organic phosphates. The relationship of these and other compounds to nuclear phosphorylation is discussed.

PHOSPHATE ABSORPTION BY PLANTS FROM HABITATS OF DIFFERENT PHOSPHATE STATUS

SUMMARYWhole plants of Urtica and Deschampsia of different phosphate status were used to study phosphate uptake. By contrast with excised roots, the attached roots of the plants showed differences both in the rate of uptake and their patterns of incorporation of phosphate. The rate of phosphate absorption from low concentrations was rather similar for the two species, but from high concentrations, Urtica absorbed at a greater rate. A greater proportion of the absorbed phosphate was incorporated into acid insoluble and acid soluble organic phosphate in Urtica than in Deschampsia. Urtica is more sensitive to phosphate concentration in its total growth rate relative shoot and root growth, and in total uptake than Deschampsia.

A biochemical-cellular-morphological explanation of the development of gastric ulcer in Shay rats.

Seven hours after pyloric ligation the acid-soluble organic phosphates increased both in the glandular and membranaceous stomach wall, whereas a pronounced decrease was found 24 hours after pyloric ligation in both parts of the stomach. The phospholipid phosphates were increased in the glandular and membranaceous parts of the stomach both at 7 and 24 hours after pyloric ligation. The deoxyribonucleic acid was less increased in the glandular than in the membranaceous stomach wall 24 hours after pyloric ligation, whereas the ribonucleic acid was only increased in the membranaceous stomach wall 7 and 24 hours after pyloric ligation.

The formation of polyphosphates in ankistrodesmus braunii by photophosphorylation in red and in far-red light under nitrogen

A simplified extraction procedure was used to study the effect of red and far-red light (683 and 712 nm) on the incorporation of 32P and on the distribution pattern of various phosphate fractions in 8 min-experiments under nitrogen. Nitrogen was used to avoid competition for energy-rich phosphate bonds between CO2-fixation and the formation of polyphosphates. The total incorporation of 32P was higher in red than in far-red light, and so was the percentage of the acidsoluble organic phosphate. In the absence of oxygen the incorporation in the dark was rather low and mainly confined to orthophosphate. The ratio between the amount of labelling of polyphosphates and that of acid-soluble organic phosphates was higher in far-red light and in the dark than in red light. DCMU, even in a nitrogen atmosphere, produced a servre inhibition in red light. This inhibition increased with increasing light intensity. The labelling of organic phosphates was more affected than that of polyphosphates, while orthophosphate incorporation was least inhibited. In far-red light, DCMU exerted little influence except at a rather high light intensity, showing that cyclic photophosphorylation was proceeding alone. Antimycin A, on the other hand, was almost ineffective in strong red light, but produced a serious inhibition in far-red light. In red light of medium intensity, antimycin effected some inhibition, although much less than DCMU. Under these conditions the effect of the two inhibitors was additive when they were applied together. Labelling of polyphosphates was more sensitive to antimycin A than labelling of acid-soluble organic phosphates. It may be concluded from the data presented that far-red light produces conditions for pure cyclic photophosphorylation, whereas a large proportion of the photophosphorylation taking place in red light in the absence of CO2 and exogenous oxygen might be regarded as “pseudocyclic”. The distribution pattern of the phosphorylated fractions under the different conditions suggests that polyphosphate formation in the light is favoured but not exclusively effected by cyclic photophosphorylation.

Induction by oxygen of respiration and phosphorylation of anaerobically grown Escherichia coli.

The changes occurring in the respiratory enzymes of anaerobically grown Escherichia coli strain B and E. coli 15 T(-)A(-)U(-)bar during exposure to oxygen were studied. Reduced nicotinamide adenine dinucleotide (NADH) oxidase activity reached its peak soon after O(2) exposure; cytochrome content and succinate oxidase activity increased more slowly, and these increases paralleled each other. The activities of isocitrate and malate dehydrogenases also increased, but the increase was less than that of the succinate and NADH oxidases; exposure to O(2) had no effect on the succinate and NADH dehydrogenase activities. On the other hand, the glycolytic activity decreased slowly after O(2) exposure. The incorporation of (32)P into acid-soluble organic phosphate esters paralleled the respiratory rate during the first 60 min after O(2) exposure, but continued to increase after the respiration reached a plateau. The sensitivity of (32)P incorporation to the uncoupler carbonyl cyanide m-chlorophenylhydrazone also increased with time. The observed relationship between the development of the respiratory chain and the energy-conserving mechanism during O(2) exposure is discussed. Synthesis of the respiratory enzymes upon exposure to oxygen was dependent on concomitant protein and ribonucleic acid synthesis but not on deoxyribonucleic acid synthesis.

Biochemical analysis of the stomach wall in normal rats.

The rat stomach wall was analysed biochemically. The biochemical extraction was carried out according to the Schneider, Schmidt-Thannhauser's method. Acid-soluble inorganic phosphate, acid-soluble organic phosphate, phospholipid phosphate, ribonucleic acidic phosphate, deoxyribonucleic acidic phosphate, phosphoproteid inorganic phosphate were measured colorimetrically according to Briggs's method. The nucleic acids were estimated by measuring the phosphate and sugar components. The biochemical analysis was made both from the total stomach, and also separately from glandular stomach and the rumen. It is concluded that these two parts of the rat's stomach differ biochemically.

Biochemical Analysis of Vagotomized Stomach Wall in Rats

The authors carried out a biochemical analysis of vagotomized rat stomach wall 2–3 weeks after a bilateral vagotomy. The biochemical extraction was performed by the Schneider-Schmidt-Thannhauser method. The phosphate fractions were measured colorimetrically according to Briggs. The nucleic acids were measured on the basis of phosphate and sugar components according to Seibert and Brown. The following compounds were determined: acid-soluble organic and inorganic phosphates, phospholipidphosphate, ribonucleic acidic phosphate, deoxyribonucleic acidic phosphate, phosphoproteid inorganic phosphate, ribonucleic acid and deoxyribonucleic acid from the whole, the glandular and the membranaceous stomach. These were compared with the some constituents of the normal rat stomach. After vagotomy a decrease was observed in acid-soluble inorganic phosphate, in organic acid-soluble phosphate, in phosphoprotein inorganic phosphate of the glandular, membranaceous and the total stomach. The phospholipid phosphate did not d...