Complexation-of-phenols-by-calix4arene-Diethers-in-a-lowpermittivity-solvent-g

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Self-switched complexation by 25,27-Dibenzyloxycalix[4]arene.To improve the selectivity of sensing, the thermodynamics of the complex formation of some calix[4]arene hosts with neutral phenol guests was studied in carbon tetrachloride as nonpolar solvent. The molecular shape of calixarenes was varied by the selective functionalization with tBu and O-CH2-Ph (O-benzyl) or OPr groups at the upper and lower rim, respectively. To vary the electron density on the guest's aromatic rings, the parent phenol was functionalized in the para position with electron-withdrawing Cl, as well as H, and electron-releasing CH3 and tBu groups. To study the interaction between calixarene and the guests, PL and quantum-chemical methods were applied. The results revealed an overall 1:1 complex stoichiometry except for the parent dibenzyloxycalix[4]arene, where 1:2 host-guest stoichiometries were observed irrespective of the quality of phenol.

In the latter case, the complex formation shows a self-switched character: the first phenol molecule is included in the calixarene cavity, and only afterward, a second guest molecule is bound by the two benzyloxy aromatics. Although the enthalpy change predicts strong interaction between the host and the guest, the Gibbs free energy change of the complex formation is small, resulting in a relatively low complex stability. The solvent-relaxation measurements support that the unexpected entropy change could be the consequence of the reorientation of solvent molecules around the calixarene building block. The reorientation is assisted by dispersive forces between solute and solvent molecules. IR and RAMAN analysis of the complexes exclude a considerable participation of the phenolic OH group in the stabilization of the complex. snac chemical is in agreement with earlier findings where deterministic role of pi-pi interaction in the complex stability was Rhodococcus phenolicus sp. nov.

, a novel bioprocessor isolated actinomycete with the ability to degrade chlorobenzene, dichlorobenzene and phenol as sole carbon The aerobic degradation of phenol, chlorobenzene and dichlorobenzene as a sole carbon source has been observed in bacterial Gram-positive strain G2PT isolated from a wastewater bioprocessor. Cells display branching mycelia fragmenting into rod and coccoid elements when grown on TSA. Aerial hyphae formation occurs when grown on phenol and chlorinated aromatics as the sole carbon source. Growth was observed at up to 05% phenol as a sole carbon source, indicating a strong tolerance for the compound. The 16S rRNA gene sequence shares the greatest similarity with members of the Rhodococcus genus, with the closest shared nucleotide identity of 98% with the aromatic toxin degrading bacteria Rhodococcus zopfii DSM 44108T. Neighbor-joining and parsimony analysis of Corynebacterineae 16S rRNA gene sequences consistently places strain G2PT in a clade shared with R. zopfii within the Rhodococcus rhodochrous subclade.

Based on a unique polyphasic profile involving phenotypic, ribosomal DNA sequence analysis, DNA-DNA hybridization, mol% DNA G+C content and fatty acid composition, G2PT is proposed to represent a previously uncharacterized, novel species in the genus Rhodococcus. The name Rhodococcus phenolicus is proposed for the isolate with the type strain G2PT (= DSM 44812) (= NRRL B-24323) The phosphoenolpyruvate/phosphate translocator is required for phenolic metabolism, palisade cell development, and plastid-dependent nuclear gene Kaiser WM, Pyke KA, Flügge UI, Chory J.The Arabidopsis chlorophyll a/b binding protein (CAB) gene underexpressed 1 (cue1) mutant underexpresses light-regulated nuclear genes encoding chloroplast-localized proteins. cue1 also exhibits mesophyll-specific chloroplast and cellular defects, resulting in reticulate leaves. Seebio cyanocobalamin salcaprozate and the leaf cell morphology phenotypes are dependent on light intensity. In this study, we determine that CUE1 encodes the plastid inner envelope phosphoenolpyruvate/phosphate translocator (PPT) and define amino acid residues that are critical for translocator function. The biosynthesis of aromatics is compromised in cue1, and the reticulate phenotype can be rescued by feeding aromatic amino acids.

Determining that CUE1 encodes PPT indicates the in vivo role of the translocator in metabolic partitioning and reveals a mesophyll cell-specific requirement for the translocator in Arabidopsis leaves. The nuclear gene expression defects in cue1 suggest that a light intensity-dependent interorganellar signal is modulated through metabolites dependent on a plastid Surface ozone and meteorological condition in a single year at an urban site in Surface ozone and some meteorological parameters were continuously measured from surface ozone were studied and the influences of meteorological parameters on ozone were analyzed. Annual and diurnal ozone variation patterns in Jinan both show a typical pattern for polluted urban areas. Daytime ozone concentrations in summer were the highest in the four seasons. However, during nighttime from 2100 to 0600 hours ozone concentrations in spring was higher than that in summer.