Phytoremediation potential of Lemna minor L. for heavy metals

Phytoremediation potential of L. minor for cadmium (Cd), copper (Cu), lead (Pb), and nickel (Ni) from two different types of effluent in raw form was evaluated in a glass house experiment using hydroponic studies for a period of 31 days. Heavy metals concentration in water and plant sample was analyzed at 3, 10, 17, 24, and 31 day. Removal efficiency, metal uptake and bio-concentration factor were also calculated. Effluents were initially analyzed for physical, chemical and microbiological parameters and results indicated that municipal effluent (ME) was highly contaminated in terms of nutrient and organic load than sewage mixed industrial effluent (SMIE). Results confirmed the accumulation of heavy metals within plant and subsequent decrease in the effluents. Removal efficiency was greater than 80% for all metals and maximum removal was observed for nickel (99%) from SMIE. Accumulation and uptake of lead in dry biomass was significantly higher than other metals. Bio-concentration factors were less than 1000 and maximum BCFs were found for copper (558) and lead (523.1) indicated that plant is a moderate accumulator of both metals. Overall, L. minor showed better performance from SMIE and was more effective in extracting lead than other metals.     

Curcumin specifically binds to the human calcium–calmodulin-dependent protein kinase IV: fluorescence and molecular dynamics simulation studies

Calcium–calmodulin-dependent protein kinase IV (CAMK4) plays significant role in the regulation of calcium-dependent gene expression, and thus, it is involved in varieties of cellular functions such as cell signaling and neuronal survival. On the other hand, curcumin, a naturally occurring yellow bioactive component of turmeric possesses wide spectrum of biological actions, and it is widely used to treat atherosclerosis, diabetes, cancer, and inflammation. It also acts as an antioxidant. Here, we studied the interaction of curcumin with human CAMK4 at pH 7.4 using molecular docking, molecular dynamics (MD) simulations, fluorescence binding, and surface plasmon resonance (SPR) methods. We performed MD simulations for both neutral and anionic forms of CAMK4-curcumin complexes for a reasonably long time (150 ns) to see the overall stability of the protein–ligand complex. Molecular docking studies revealed that the curcumin binds in the large hydrophobic cavity of kinase domain of CAMK4 through several hydrophobic and hydrogen-bonded interactions. Additionally, MD simulations studies contributed in understanding the stability of protein–ligand complex system in aqueous solution and conformational changes in the CAMK4 upon binding of curcumin. A significant increase in the fluorescence intensity at 495 nm was observed (λ_exc = 425 nm), suggesting a strong interaction of curcumin to the CAMK4. A high binding affinity (K_D = 3.7 × 10^?8 ± .03 M) of curcumin for the CAMK4 was measured by SPR further indicating curcumin as a potential ligand for the CAMK4. This study will provide insights into designing a new inspired curcumin derivatives as therapeutic agents against many life-threatening diseases.     

Lactate dehydrogenase in two digenetic trematodes and their host

Polyacrylamide gel electrophoresis of the two digenetic trematodes, Gigantocotyle explanalum from the liver and Gastrothylax crumenifer from the rumen of the water buffalo, Bubalus bubalis revealed the presence of at least six and seven isoenzymes of lactate dehydrogenase (LDH), respectively in a partially purified enzyme preparation. The respective host tissues showed five isoenzymes of LDH, which are characteristic to the vertebrates. Both parachloromercuribenzoate and iodoacetate affected the LDH activity of the parasites and host tissues differently. Spectrophotometric analysis also showed different specific activity and susceptibility to the action of thiol inhibitors. The host LDH was quite stable at 57°C for 30 min, but that of the parasites was less stable.     

Isolation and characterization of a lead (Pb) tolerant <Emphasis Type="Italic">Pseudomonas aeruginosa</Emphasis> strain HF5 for decolorization of reactive red-120 and other azo dyes

Presence of heavy metals including lead (Pb) in the textile effluents is a crucial factor affecting the growth and potential of the dye decolorizing bacterial strains. This work was planned to isolate and characterize a bacterial strain exhibiting the potential to decolorize a range of azo dyes as well as the resistance to Pb. In this study, several Pb tolerant bacteria were isolated from effluents of textile industry. These bacterial isolates were screened for their potential of decolorizing the reactive red-120 (RR120) azo dye with presence of Pb (50 mg L^?1). The most efficient isolate was further characterized for its potential to resist Pb and decolorize different azo dyes under varying cultural and incubation conditions. Out of the total 82 tested bacterial isolates, 30 bacteria were found to have varying potentials to resist the presence of lead (Pb) and carry out decolorization of an azo dye reactive red-120 (RR120) in the medium amended with Pb (50 mg L^?1). The most efficient selected bacterium, Pseudomonas aeruginosa strain HF5, was found to show a good potential not only to grow in the presence of considerable concentration of Pb but also to decolorize RR120 and other azo dyes in the media amended with Pb. The strain HF5 completely (>?90%) decolorized RR120 in mineral salt medium amended with 100 mg L^?1 of Pb and 20 g L^?1 NaCl. This strain also considerably (>?50%) decolorized RR120 up to the presence of 2000 mg L^?1 of Pb and 50 g L^?1 of NaCl but with reduced rate. The optimal decolorization of RR120 by HF5 was achieved when the pH of the Pb amended (100 mg L^?1) mineral salt media was adjusted at 7.5 and 8.5. Interestingly, this strain also showed the tolerance to a range of metal ions with varying MIC values. The Pseudomonas aeruginosa strain HF5 harboring the unique potentials to grow and decolorize the azo dyes in the presence of Pb is envisaged as a potential bioresource for devising the remediation strategies for treatment of colored textile wastewaters loaded with Pb and other heavy metal ions.     

AN UNUSUAL KIND OF DISTYLY IN QUINCHAMALIUM CHILENSE (SANTALACEAE) ON VOLCÁN CASABLANCA,SOUTHERN CHILE

In mature flowers of the southern Andean parasitic herb, Quinchamalium chilense (Santalaceae), the stigmas and anthers are closer together in the pin morph than in the thrum morph. While the stigmas and anthers of the two morphs are in reciprocal positions as the flowers open, such reciprocity is lost as the result of post-anthesis allometric growth of the styles and stamens. Experimental pollinations reveal that both morphs of Q. chilense are self-compatible. Natural fruit set is higher on the pin morph. The latter is also statistically under-represented in natural populations with respect to a 1:1 ratio for pins and thrums. Pin flowers produce larger numbers of pollen grains than thrum flowers and pollen of pin flowers is smaller in size than that of thrum flowers. Higher fruit set on the pin morph is consistent with some tendency towards subdioecious breeding behavior, although an expected excess of geitonogamous pollinations on the pin morph might also be contributing to the difference in fruit set on the two morphs. The unusual floral morphology of Q. chilense could have evolved as a result of selection for larger flowers by certain pollinator groups less likely to effect geitonogamous pollination. Alternatively, extended development of post-anthesis flowers might be a reflection of selection for an array of flower sizes on individual inflorescences, producing a target effect for pollinator attraction. The evolution of such inflorescence morphology would have been facilitated by the fact that a trend in the direction of subdioecious breeding behavior accrues the same outcrossing advantages as strict distyly. Precise information on periods of stigma receptivity is required to further our understanding of the floral morphology of Q. chilense.     

Synthesis and characterization of erbium‐doped YAlO3 phosphor

In the yttrium aluminium system, the YAlO₃ phosphor is a prominent host because of the yttrium aluminium ratio (1:1). Phosphor was synthesized by the solid‐state reaction method at variable concentrations of erbium (0.1–2.5 mol%). This method is suitable for large‐scale production and is a less time‐consuming method when compared with the soft synthesis method. The prepared sample was characterized by X‐ray diffraction technique and the crystallite size was calculated by Scherer's formula. Vibrational and bending analysis of prepared phosphor for optimized concentration of erbium ion is described based on the Fourier transform infrared spectroscopic technique. The photoluminescence (PL) emission spectra of prepared phosphor for variable concentrations of erbium ion were recorded and the excitation spectrum was found to be at 291 nm with three shoulder peaks at 305, 270 and 242 nm. For 291 nm excitation, the emission spectrum was found at 546 nm and 552 nm. PL intensity increased with increasing concentrations of erbium and after 2 mol% emission intensity decreased due to concentration quenching. Spectrophotometric determination of YAlO₃:Er³⁺ is described by CIE co‐ordinates and shows an intense emission in the green region such that the prepared phosphor can act as a single host for green light emission. Thermoluminescence glow curve analysis of the YAlO₃:Er³⁺ phosphor was recorded for different ultraviolet (UV) light exposures and gamma exposure. Different gamma doses 0.5–2 kGy show a linear response. Kinetic parameters were calculated by the peak shape method. Copyright © 2015 John Wiley & Sons, Ltd.     

Stimulation of Inositol 1,4,5-Trisphosphate (IP3) Receptor Subtypes by Adenophostin A and Its Analogues

Inositol 1,4,5-trisphosphate receptors (IP₃R) are intracellular Ca²⁺ channels. Most animal cells express mixtures of the three IP₃R subtypes encoded by vertebrate genomes. Adenophostin A (AdA) is the most potent naturally occurring agonist of IP₃R and it shares with IP₃ the essential features of all IP₃R agonists, namely structures equivalent to the 4,5-bisphosphate and 6-hydroxyl of IP₃. The two essential phosphate groups contribute to closure of the clam-like IP₃-binding core (IBC), and thereby IP₃R activation, by binding to each of its sides (the α- and β-domains). Regulation of the three subtypes of IP₃R by AdA and its analogues has not been examined in cells expressing defined homogenous populations of IP₃R. We measured Ca²⁺ release evoked by synthetic adenophostin A (AdA) and its analogues in permeabilized DT40 cells devoid of native IP₃R and stably expressing single subtypes of mammalian IP₃R. The determinants of high-affinity binding of AdA and its analogues were indistinguishable for each IP₃R subtype. The results are consistent with a cation-π interaction between the adenine of AdA and a conserved arginine within the IBC α-domain contributing to closure of the IBC. The two complementary contacts between AdA and the α-domain (cation-π interaction and 3″-phosphate) allow activation of IP₃R by an analogue of AdA (3″-dephospho-AdA) that lacks a phosphate group equivalent to the essential 5-phosphate of IP₃. These data provide the first structure-activity analyses of key AdA analogues using homogenous populations of all mammalian IP₃R subtypes. They demonstrate that differences in the Ca²⁺ signals evoked by AdA analogues are unlikely to be due to selective regulation of IP₃R subtypes.     

Changes in albumin precursor and heat shock protein 70 expression and their potential role in response to corneal epithelial wound repair

Many proteins displayed differential expression (either up- or down-regulation) when proteome of migrating and non-migrating epithelium was assessed using 2-DE and ESI-Q-TOF MS/MS. From the up-regulated set, we have identified for the first time a 69-kDa albumin precursor protein with four peptides sequences and 70-kDa heat shock protein (hsp70) with one peptide in the active phase of cell migration (48 h) during the healing process. Western blot analysis was used to further characterize these proteins at different phases (24, 48 and 72 h) of healing. An increase in the mRNA expression (measured using RT-PCR) in the active migration phase (48 h) for albumin precursor and hsp70 was also observed. Furthermore, co-immunoprecipitation studies with anti-albumin precursor and anti-hsp70 antibodies, followed by immunoblotting with anti-fibronectin antibody demonstrated a novel and biologically relevant interaction between albumin precursor protein and fibronectin in corneal epithelial wound healing but not with hsp70. The increased gene and protein expression of albumin and hsp70 during the active phase of cell migration (48 h) in the corneal epithelium suggests their possible role in corneal wound healing. These findings may have broader implications for developing therapeutic strategies for treating wound healing disorders.