A natural isolate of Pseudomonas maltophila which degrades aromatic sulfonic acids

Abstract A natural isolate, designated BSA56, which was originally selected for growth with benzene sulfuric acid as sole carbon and energy source, was identified as a strain of Pseudomonas maltophila . Strain BSA56 grew on a wide range of aromatic sulfonic acids and was shown to release sulfite from benzene sulfonic acid and 2-napthalene sulforic acid. Although it also grew on toluene sulfonic acid and pyridine sulfonic acid, no significant sulfite release was observed with these substrates. Release of sulfite from benzene sulfonic acid was greatly promoted by the presence of glycerol. The ability to release sulfite was induced by growth in the presence of benzene sulfonic acid and was repressed almost entirely by substrates allowing rapid growth such as acetate. Strain BSA56 grew better at 30°C than 37°C on most aromatic substrates, but the reverse was true for most aromatic sulfonates. Several mutants of BSA56 were isolated with defects in benzoate, salicylate, or gentisate metabolism. However, all these mutants retained the ability to degrade the aromatic sulfonates.     

Migration of Naphthalene through Low Organic Content Sandy Soil Columns: Comparison of Unsaturated and Saturated Conditions

The transient transport of naphthalene through low organic matter content soil columns was investigated in different water-saturation and flow conditions. Some parameters were tested as flow rate, column height, and water saturation conditions. The soil was a clayed sandy soil from the Algerian coast near Boumerdes. The organic carbon content was 0.13% and the main mineral components were quartz (88%), clays minerals (7%) and calcite (3%). The height of the packing of the soil column (5.1 cm in diameter) varied from 15 to 40 cm. Simultaneous step injections of inert tracer (calcium chloride) and naphthalene at 10 mg L^?1 were performed. Tracer and naphthalene breakthrough curves (BTCs) were measured continuously by conductimetry and UV – 220 nm, respectively. The BTCs were simulated using the classical mixing cells in series with exchange model (MCE). In unsaturated conditions the comparison of the mean residence time of tracer BTCs with the geometrical pore volume gave us access to average water saturation along the column as a function of height. The higher the soil bed was, the higher the mean water saturation. The comparison of naphthalene distribution coefficients (K_d) in different flow conditions with the theoretical value from the Karickhoff law showed that in saturated conditions the obtained value was close to the theoretical one. In unsaturated conditions, the measured naphthalene K_d's were much lower than the theoretical value and correlated to the water saturation.     

Bilayer heterojunction solar cell based on naphthalene bis-benzimidazole

We have fabricated a bilayer heterojunction solar cell consisting of p-n active layers of naphthalenetetracarboxylic bis-benzimidazole, N-CON, and zinc phthalocyanine, ZnPc. Conjugated naphthalene derivative of naphthalene bis-benzimidazole was employed as an electron acceptor. Bilayer solar cells were produced by successive evaporation of zinc phthalocyanine, ZnPc, and naphthalene bis-benzimidazole, N-CON, on glass substrates coated with indium doped tin oxide, ITO/PEDOT:PSS/ZnPc/N-CON/Al. Photovoltaic characteristics of bilayer cell were measured under simulated AM 1.5 sun illumination (V_oc = 0.50 V, J_sc = 2.11 mA/cm², FF = 0.51, η = 0.54%). Efficiency of the cell was discussed in relation to energy gap and work functions of the thin layers.     

Plant growth-promoting Pseudomonas bearing catabolic plasmids: Naphthalene degradation and effect on plants

Two IncP-9 naphthalene degradative plasmids pOV17 and pBS216 were transferred into plant growth-promoting Pseudomonas which were represented by species P. aureofaciens, P. chlororaphis, P. fluorescens, and P. putida. The strains with the same plasmid differed significantly by their growth parameters, stability of the plasmid and plant protective effect from naphthalene action. Strains P. putida 53a(pOV17) and P. chlororaphis PCL1391(pOV17) demonstrated higher population number in the rhizosphere. Moreover, they protected the mustard plants from naphthalene toxic influence more effectively than the wild type strain P. aureofaciens OV17(pOV17). The activity of catechol-2,3-dioxygenase in the strains with the plasmid pOV17 was higher than that in strains with the plasmid pBS216. The strain P. putida 53a(pOV17) with high catechol-2,3-dioxygenase activity has been demonstrated to have the best protective effect. The strain P. putida 53a(pBS216) without catechol dioxygenases activities did not have protective effect but suppressed the plant germination.     

Episodic positive selection during the evolution of naphthalene dioxygenase to nitroarene dioxygenase

Using different maximum-likelihood models of adaptive evolution, signatures of natural selective pressure, operating across the naphthalene family of dioxygenases, were examined. A lineage- and branch-site specific combined analysis revealed that purifying selection pressure dominated the evolutionary history of the enzyme family. Specifically, episodic positive Darwinian selection pressure, affecting only a few sites in a subset of lineages, was found to be responsible for the evolution of nitroarene dioxygenases (NArDO) from naphthalene dioxygenase (NDO). Site-specific analysis confirmed the absence of diversifying selection pressure at any particular site. Different sets of positively selected residues, obtained from branch-site specific analysis, were detected for the evolution of each NArDO. They were mainly located around the active site, the catalytic pocket and their adjacent regions, when mapped onto the 3D structure of the α-subunit of NDO. The present analysis enriches the current understanding of adaptive evolution and also broadens the scope for rational alteration of substrate specificity of enzyme by directed evolution.     

Review ArticleNaphthalene Combretastatin Analogues: Synthesis,Cytotoxicity and Antitubulin Activity

Synthesis and evaluation of new combretastatin analogues with varied modifications on the bridge and the aromatic rings, have shown that the 2-naphthyl moiety is a good surrogate for the 3-hydroxy-4-methoxyphenyl (B-ring) of combretastatin A-4. Other bicyclic systems, such as 6(7)-quinolyl and 5-indolyl, can replace the B-ring, but they produce less potent analogues in the cytotoxicity and tubulin polymerization inhibition assays. Other modifications are detrimentral for the potency of the studied analogues. The 2-naphthyl combretastatin 53 and the related 6-quinolyl combretastatin 106 analogues are the most potent among the derivatives of this type, whereas 92 and 95 are the most potent among the naphthalene derivatives with a heterocycle in the bridge. Previous and new results in this family of combretastatin analogues are discussed.     

In vitro study on the effect of cytokines and auxins addition to growth medium on the micropropagation and rooting of Paulownia species (Paulownia hybrid and Paulownia tomentosa)

This study represents an efficient preliminary protocol for in vitro mass production of two Paulownia species (Paulownia hybrid and Paulownia tomentosa) seedlings by using seed explant. Different concentrations of benzyladenine (BA) or Kinetin (Kin) (0.0, 2.0, 4.0, 6.0, 8.0 and 10.0 mg/L) were tested during multiplication stage. The number of shoots/explants was significantly increased with increasing either BA or Kin concentration; however, the shoot length significantly decreased. Data show that media fortified by BA (10 mg/L) combined with indole butyric acid (IBA) at 1.0 or 1.5 mg/L recorded the highest number of shoots/explant (9.13 and 9.25, respectively). After six weeks during the multiplication stage, data cleared that media fortified by benzyladenine (10 mg/L) combined with IBA at 0.5 mg/L recorded the highest shoot length (3.23 cm). The inclusion of indole butyric acid (IBA) or naphthalene acetic acid (NAA) at 1.0–1.5 mg/L to the medium significantly increased the number of roots/plantlets and the highest root length. The results indicated that IBA supplementation was more effective than NAA for in vitro rooting of both Paulownia species. The best treatment for multiplication was 10 mg/L and 8.0–10 mg/L BA for P. hybrid and P. tomentosa, respectively. Peat moss and sand (1:1, v/v) or peat moss and sand (1:2, v/v) were investigated as soil mixture during the adaptation stage. The results referred that Paulownia species plantlets were successfully survived (100 %) in soil mixture contained peat moss: sand (1:2, v/v). This mixture recorded the highest values of plantlet height and number of leaves/plantlets.     

Alleviation of salinity stress effects on agro-physiological traits of wheat by auxin,glycine betaine,and soil additives

Soil salinity is a major constraint to wheat production; it causes a severe reduction in wheat growth and yield. Alleviation of salinity effects on physiological, biochemical, and yield of wheat cultivars; Sids 14 and Misr 3 using some soil additions (control, Molasses and Humic acid), compatible solutes, and growth regulators (water as control, Naphthalene acetic acid, and Glycine betaine) were investigated in salt-affected soils. Results indicated that Misr 3 was superior to Sids 14 in all studied characteristics except flag leaf area, relative water content, plant height and recorded lower and desirable value of leaf temperature. The addition of Molasses (24 L ha^?1) or Humic acid (12 L ha^?1) significantly increased physiological and biochemical characteristics. At the same time, flag leaf temperature, proline, and malondialdehyde (MDA) content were decreased, yield and its attributes also increased except No. kernel spike-1. Foliar spray of Naphthalene acetic acid (NAA) at 30 mg L^?1. or glycine betaine (GB 100 mM) also positively affected the studied characteristics, where Glycine betaine recorded the highest Relative water content and Fv/Fm. In contrast, NAA recorded the most increased Catalase (CAT) activity, and the Number of spikes m^?2 and insignificant differences were observed between them in grain yield. It could be recommended the cultivation of Misr 3 with Molasses and GB under saline soils.     

Alterations in the proteome of the respiratory tract in response to single and multiple exposures to naphthalene

Protein adduction is considered to be critical to the loss of cellular homeostasis associated with environmental chemicals undergoing metabolic activation. Despite considerable effort, our understanding of the key proteins mediating the pathologic consequences from protein modification by electrophiles is incomplete. This work focused on naphthalene (NA) induced acute injury of respiratory epithelial cells and tolerance which arises after multiple toxicant doses to define the initial cellular proteomic response and later protective actions related to tolerance. Airways and nasal olfactory epithelium from mice exposed to 15 ppm NA either for 4 h (acute) or for 4 h/day × 7 days (tolerant) were used for label‐free protein quantitation by LC/MS/MS. Cytochrome P450 2F2 and secretoglobin 1A1 are decreased dramatically in airways of mice exposed for 4 h, a finding consistent with the fact that CYPs are localized primarily in Clara cells. A number of heat shock proteins and protein disulfide isomerases, which had previously been identified as adduct targets for reactive metabolites from several lung toxicants, were upregulated in airways but not olfactory epithelium of tolerant mice. Protein targets that are upregulated in tolerance may be key players in the pathophysiology associated with reactive metabolite protein adduction. All MS data have been deposited in the ProteomeXchange with identifier PXD000846 ( http://proteomecentral.proteomexchange.org/dataset/PXD000846 ).     

Four new glycosides from the seeds of Cassia obtusifolia

Four new glycosides, including one anthraquinone glycoside (1), one naphthalene glycoside (2), and two naphthopyrone glycosides (3–4), with 10 known compounds (5–14) were isolated from the seeds of Cassia obtusifolia L. The new structures were determined by spectroscopic analysis and chemical transformations.