Search results for "Phosphor"
showing 10 items of 1952 documents
ElaC Encodes a Novel Binuclear Zinc Phosphodiesterase
2002
ElaC is a widespread gene found in eubacteria, archaebacteria, and mammals with a highly conserved sequence. Two human ElaC variants were recently associated with cancer (Tavtigian, S. V., Simard, J., Teng, D. H., Abtin, V., Baumgard, M., Beck, A., Camp, N. J., Carillo, A. R., Chen, Y., Dayananth, P., Desrochers, M., Dumont, M., Farnham, J. M., Frank, D., Frye, C., Ghaffari, S., Gupte, J. S., Hu, R., Iliev, D., Janecki, T., Kort, E. N., Laity, K. E., Leavitt, A., Leblanc, G., McArthur-Morrison, J., Pederson, A., Penn, B., Peterson, K. T., Reid, J. E., Richards, S., Schroeder, M., Smith, R., Snyder, S. C., Swedlund, B., Swensen, J., Thomas, A., Tranchant, M., Woodland, A. M., Labrie, F., Sko…
Applications and stereoselective syntheses of P-chirogenic phosphorus compounds.
2016
International audience; Phosphorus compounds bearing chirality on the P-center are usually qualified as P-chirogenic or P-stereogenic. This chemical class concerns natural products, agrochemistry, molecular materials, biology and pharmacy, although it is certainly in coordination chemistry and in asymmetric catalysis using chiral transition metal complexes that P-chirogenic phosphorus compounds are the most used. The chiral phosphine ligands and their uses in asymmetric metal-catalyzed reactions have been widely reviewed in literature. However, an overview covering the applications as well as the stereoselective syntheses of all classes of phosphorus compounds has not yet been provided. Thi…
Organophosphonate utilization by the wild‐type strain of cladosporium resinae
1997
We studied the biodegradation of compounds containing phosphorus‐to‐carbon bond by using wild‐type strain of Cladosporium resinae. The substrate specificity of the strain was studied and we found that it is able to utilize a range of structurally diverse organophosphonates as a sole source of phosphorus. This ability is inducible as indicated by the presence of a lag phase of the growth. A popular herbicide glyphosate is also degraded by the fungi. This indicates that Cladosporium resinae may play an important role in biodegradation of this herbicide. The strain which we used, however, did not metabolise any phosphonates when they served as the sole carbon or nitrogen sources.
Temperature, phosphorus and species composition will all influence phytoplankton production and content of polyunsaturated fatty acids
2023
Temperature increases driven by climate change are expected to decrease the availability of polyunsaturated fatty acids in lakes worldwide. Nevertheless, a comprehensive understanding of the joint effects of lake trophic status, nutrient dynamics and warming on the availability of these biomolecules is lacking. Here, we conducted a laboratory experiment to study how warming (18–23°C) interacts with phosphorus (0.65–2.58 μM) to affect phytoplankton growth and their production of polyunsaturated fatty acids. We included 10 species belonging to the groups diatoms, golden algae, cyanobacteria, green algae, cryptophytes and dinoflagellates. Our results show that both temperature and phosphorus w…
Phosphorylation of mismatch repair proteins MSH2 and MSH6 affecting MutSα mismatch-binding activity
2002
Mismatch repair (MMR) is involved in the removal of mispaired bases from DNA and thus plays an important role in the maintenance of genomic stability and the prevention of mutations and cancer. Moreover, MMR triggers genotoxicity and apoptosis upon processing of DNA lesions such as O6-methylguanine. Whereas the enzymology of MMR has been elucidated in great detail, only limited data are available concerning its regulation. Here we show that the major mismatch-binding proteins MSH2 and MSH6, forming the MutSalpha complex, are phosphorylated in vitro by protein kinase C and casein kinase II, but not by protein kinase A. Phosphorylation of MSH2 and MSH6 was also found within the cell, with MSH…
1,1′-(Diphosphene-1,2-diyl)bis(2,2,6,6-tetramethylpiperidine)
2017
The title compound, C18H36N2P2, crystallizes in the triclinic space groupP-1 with two independent molecules in the asymmetric unit. Both molecules adopt atransconfiguration of the tetramethylpiperidine units along the P=P axis. The crystal packing is stabilized only by van der Waals interactions.
Factors controlling hydrochemical and trophic state variables in 86 shallow lakes in Europe
2003
In order to disentangle the causes of variations in water chemistry among European shallow lakes, we performed standardised sampling programs in 86 lakes along a latitudinal gradient from southern Spain to northern Sweden. Lakes with an area of 0.1 to 27 000 ha and mean depth of 0.4–5.6 m located in low to high altitudes were investigated within the EC project ECOFRAME 1–4 times during June–October 2000–2001. Several variables like conductivity, alkalinity, abundance of submerged plants, concentrations of suspended solids, total nitrogen and phosphorus were latitude-dependent decreasing from south to north. Secchi depth, concentrations of total nitrogen, total phosphorus, suspended solids, …
Harnessing Fluorescence versus Phosphorescence Branching Ratio in (Phenyl)n-Bridged (n = 0–5) Bimetallic Au(I) Complexes
2013
We have designed and synthesized a series of Au(I) complexes bearing either an alkynyl–(phenylene)n–diphosphine (A-0–A-3) or a (phenylene)n–diphosphine (B-1–B-5) bridge, among which the effective distance between Au(I) and the center of the emitting ππ* chromophore can be fine-tuned via the insertion of various numbers of phenylene spacers. We then demonstrated for the first time in a systematic manner the decrease of rate constant for S1 → T1 intersystem crossing (ISC) kisc as the increase of the effective distance. The results also unambiguously showed that the phosphorescence could be harvested via higher S0 → Sn (n > 1) electronic excitation, followed by fast Sn → Tm ISC and then the po…
Population Dynamic of Algae and Bacteria in an Oxidation Channel
2003
A study on algae and bacteria population changes, as a function of time, was carried out in a pilot scale oxidation channel bioreactor using a carrousel system. Total Coliforms, Pseudomonas aeruginosa, and Streptococcus faecalis, the most common bacteria found in sewage, Scenedesmus obliquus and Chlorella vulgaris were the microalgae considered in this work. Physicochemical parameters such as COD, BOD, Chlorophyll a, nitrogen, and phosphorous compounds were studied and determined during the experiments. It was demonstrated that the level of wastewater contamination could be predicted based on the bacterial and algae composition. The relationships between the algae and bacteria population, a…
Biological nutrient removal in membrane bioreactors: denitrification and phosphorus removal kinetics.
2007
The impact of including membranes for solid liquid separation on the kinetics of nitrogen and phosphorus removal was investigated. To achieve this, a membrane bioreactor (MBR) biological nutrient removal (BNR) activated sludge system was operated. From batch tests on mixed liquor drawn from the MBR BNR system, denitrification and phosphorus removal rates were delineated. Additionally the influence of the high total suspended solids concentrations present in the MBR BNR system and of the limitation of substrate concentrations on the kinetics was investigated. Moreover the ability of activated sludge in this kind of system to denitrify under anoxic conditions with simultaneous phosphate uptak…