Leishmania amazonensis Engages CD36 to Drive Parasitophorous Vacuole Maturation.

Leishmania amastigotes manipulate the activity of macrophages to favor their own success. However, very little is known about the role of innate recognition and signaling triggered by amastigotes in this host-parasite interaction. In this work we developed a new infection model in adult Drosophila to take advantage of its superior genetic resources to identify novel host factors limiting Leishmania amazonensis infection.

Simultaneous removal of phosphorus and EfOM using MIEX, coagulation, and low-pressure membrane filtration.

The feasibility of using magnetic ion exchange (MIEX) treatment, in-line alum coagulation, and low-pressure membrane filtration was investigated for the simultaneous removal of total phosphorus (TP) and effluent organic matter (EfOM) from biologically treated wastewater. The focus was also placed on minimizing fouling of polyvinylidene fluoride and polyethersulfone membranes, which are the most commonly used low-pressure membranes in new and retrofit wastewater treatment plants. MIEX alone was effective for the removal of EfOM, and MIEX plus a small alum dose was very effective in removing both EfOM and TP.

Evaluation of acidity estimation methods for mine drainage, Pennsylvania, USA.

Eighteen sites impacted by abandoned mine drainage (AMD) in Pennsylvania were sampled and measured for pH, acidity, alkalinity, metal ions, and sulfate. This study compared the accuracy of four acidity calculation methods with measured hot peroxide acidity and identified the most accurate calculation method for each site as a function of pH and sulfate concentration. Method E1 was the sum of proton and acidity based on total metal concentrations; method E2 added alkalinity; method E3 also accounted for aluminum speciation and temperature effects; and method E4 accounted for sulfate speciation.

Fate of hydrolyzed Al species in humic acid coagulation.

The hydrolysis of Al-based coagulants in acidic conditions is necessary for the removal of organic matter by the coagulation/sedimentation process. However, interactions between hydrolyzed Al species and organic matter are complicated and this makes it difficult to optimize coagulant dosing for organics removal. The goal of this study was to investigate the reactions of hydrolyzed Al species in the coagulation of organic matter.

Electrochemical struvite precipitation from digestate with a fluidized bed cathode microbial electrolysis cell.

Microbial electrolysis cells (MECs) can be used to simultaneously convert wastewater organics to hydrogen and precipitate struvite, but scale formation at the cathode surface can block catalytic active sites and limit extended operation. To promote bulk phase struvite precipitation and minimize cathode scaling, a two-chamber MEC was designed with a fluidized bed to produce suspended particles and inhibit scale formation on the cathode surface. MEC operation elevated the cathode pH to between 8.

Photoautotrophic hydrogen production by eukaryotic microalgae under aerobic conditions.

Eukaryotic algae and cyanobacteria produce hydrogen under anaerobic and limited aerobic conditions. Here we show that novel microalgal strains (Chlorella vulgaris YSL01 and YSL16) upregulate the expression of the hydrogenase gene (HYDA) and simultaneously produce hydrogen through photosynthesis, using CO2 as the sole source of carbon under aerobic conditions with continuous illumination. We employ dissolved oxygen regimes that represent natural aquatic conditions for microalgae.

Ultrasonic disintegration of microalgal biomass and consequent improvement of bioaccessibility/bioavailability in microbial fermentation.

Background: Microalgal biomass contains a high level of carbohydrates which can be biochemically converted to biofuels using state-of-the-art strategies that are almost always needed to employ a robust pretreatment on the biomass for enhanced energy production. In this study, we used an ultrasonic pretreatment to convert microalgal biomass (Scenedesmus obliquus YSW15) into feasible feedstock for microbial fermentation to produce ethanol and hydrogen. The effect of sonication condition was quantitatively evaluated with emphases on the characterization of carbohydrate components in microalgal suspension and on subsequent production of fermentative bioenergy.

Identification of the factors that control synthesis and accumulation of a therapeutic protein, human immune-regulatory interleukin-10, in Arabidopsis thaliana.

Plants are one of the most economical platforms for large-scale production of recombinant proteins for biopharmaceutical and industrial uses. A large number of human recombinant proteins of therapeutic value have been successfully produced in plant systems. One of the main technical challenges of producing recombinant proteins in plants is to obtain sufficient level of protein.

As(V) and As(III) reactions on pristine pyrite and on surface-oxidized pyrite.

Reactions of As(III) and As(V) with pyrite were investigated using pristine pyrite (produced and reacted in a rigorously anoxic environment with P(O2)<10(-8)atm) and using surface-oxidized pyrite (produced under anoxic conditions, exposed to air, then stored and reacted under rigorously anoxic conditions). Results with surface-oxidized pyrite were similar to previously reported arsenic-pyrite results. However As(III) adsorbed over a broader pH range on pristine pyrite than on surface-oxidized pyrite, As(V) adsorbed over a narrower pH range on pristine pyrite than on surface-oxidized pyrite, and adsorbed As(V) on pristine pyrite was reduced to As(III) but adsorbed As(V) was not reduced with surface-oxidized pyrite.

Structure of an asymmetric ternary protein complex provides insight for membrane interaction.

Plasma membrane repair involves the coordinated effort of proteins and the inner phospholipid surface to mend the rupture and return the cell back to homeostasis. Here, we present the three-dimensional structure of a multiprotein complex that includes S100A10, annexin A2, and AHNAK, which along with dysferlin, functions in muscle and cardiac tissue repair. The 3.

Comparison of two fractionation strategies for characterization of wastewater effluent organic matter and diagnosis of membrane fouling.

Two fractionation strategies were compared for characterizing organic components in effluent organic matter (EfOM) and natural organic matter (NOM). The first method is widely used and requires sample acidification and then re-neutralization during sequential organic removals onto resins. The second method uses a different suite of separation methods, does not require pH manipulation, and sequentially removes particles, colloids, organic acids, and hydrophobic neutrals without the need for adjusting pH.

Reduction of As(V) to As(III) by commercial ZVI or As(0) with acid-treated ZVI.

Zero-valent iron (ZVI) consists of an elemental iron core surrounded by a shell of corrosion products, especially magnetite. ZVI is used for in situ removal or immobilization of a variety of contaminants but the mechanisms for removal of arsenic remain controversial and the mobility of arsenic after reaction with ZVI is uncertain. These issues were addressed by separately studying reactions of As(V) with magnetite, commercial ZVI, and acid-treated ZVI.

Identification of calcium-independent and calcium-enhanced binding between S100B and the dopamine D2 receptor.

S100B is a dimeric EF-hand protein that undergoes a calcium-induced conformational change and exposes a hydrophobic protein-binding surface. Recently S100B was identified as a binding partner of the dopamine D2 receptor in a bacterial two-hybrid screen involving the third intracellular loop (IC3). The low in vivo calcium concentration in bacteria (100-300 nM) suggests this interaction may occur in the absence of calcium.

Discovery and characterization of a nonphosphorylated cyclic peptide inhibitor of the peptidylprolyl isomerase, Pin1.

Phage panning led to the discovery of a disulfide-cyclized peptide CRYPEVEIC that inhibits Pin1 activity with a K(I) of 0.5 μM. NMR chemical shift perturbation experiments show that cyclic CRYPEVEIC binds to the active site of Pin1.

Efficient recovery of nano-sized iron oxide particles from synthetic acid-mine drainage (AMD) water using fuel cell technologies.

Acid mine drainage (AMD) is an important contributor to surface water pollution due to the release of acid and metals. Fe(II) in AMD reacts with dissolved oxygen to produce iron oxide precipitates, resulting in further acidification, discoloration of stream beds, and sludge deposits in receiving waters. It has recently been shown that new fuel cell technologies, based on microbial fuel cells, can be used to treat AMD and generate electricity.

Nitrite reduction with hydrous ferric oxide and Fe(II): stoichiometry, rate, and mechanism.

Fe(II)/Fe(III) oxide is an important redox couple in environmental systems. Recent studies have revealed unique characteristics of Fe(II)/Fe(III) oxide and reactions with oxidizing or reducing agents. Nitrite was used as an oxidizing agent in this study in order to probe details of these reactions and hydrous ferric oxide (HFO) was used as the Fe(III) oxide phase.

Effects of wastewater effluent organic materials on fouling in ultrafiltration.

The objective was to determine the effects of wastewater effluent organic materials (EfOM) on fouling of ultrafilters (100kDa polyethersulfone (PES)). EfOM constituents were sequentially removed, first by removing particles down to the approximate ultrafilter pore size and then by removing dissolved EfOM based on functionality. Particles and colloids >20nm accounted for 19% of total organic carbon (TOC), including 96% of EfOM >100kDa.

Coadsorption of arsenic(III) and arsenic(V) onto hydrous ferric oxide: effects on abiotic oxidation of arsenic(III), extraction efficiency, and model accuracy.

Single solute adsorption and coadsorption of As(III) and As(V) onto hydrous ferric oxide (HFO), oxidation of As(III), and extraction efficiencies were measured in 0.2 atm O2. Oxidation was negligible for single-adsorbate experiments, but significant oxidation was observed in the presence of As(V) and HFO.

Reduction of U(VI) by Fe(II) in the presence of hydrous ferric oxide and hematite: effects of solid transformation, surface coverage, and humic acid.

Fe(II) was added to U(VI)-spiked suspensions of hydrous ferric oxide (HFO) or hematite to compare the redox behaviors of uranium in the presence of two different Fe(III) (oxyhydr)oxides. Experiments were conducted with low or high initial sorption density of U(VI) and in the presence or absence of humic acid (HA). About 80% of U(VI) was reduced within 3 days for low sorbed U(VI) conditions, with either hematite or HFO.

Electricity generation from synthetic acid-mine drainage (AMD) water using fuel cell technologies.

Acid-mine drainage (AMD) is difficult and costly to treat. We investigated a new approach to AMD treatment using fuel cell technologies to generate electricity while removing iron from the water. Utilizing a recently developed microbial fuel cell architecture, we developed an acid-mine drainage fuel cell (AMD-FC) capable of abiotic electricity generation.

Solubility of hematite revisited: effects of hydration.

Measured pH and dissolved ferric iron concentration ([Fe(III)diss]) in contact with well-characterized hematite indicated an equilibrium with hematite immediately after synthesis, but [Fe(III)diss] increased with hydration time to be consistent with the predicted solubility of goethite or hydrous ferric oxide (HFO), hydrated analogues of hematite. X-ray diffraction did not detect structural modification of hematite after 190 days of hydration, but Mössbauer spectroscopy detected hydration that penetrated several crystalline layers. When the hematite suspension was diluted with water, solids were invariably identified as hematite, but [Fe(III)diss] and pH indicated an equilibrium with goethite or HFO.

Effect of natural organic matter on zinc inhibition of hematite bioreduction by Shewanella putrefaciens CN32.

The effect of zinc on the biological reduction of hematite (alpha-Fe2O3) by the dissimilatory metal-reducing bacterium (DMRB) Shewanella putrefaciens CN32 was studied in the presence of four natural organic materials (NOMs). Experiments were performed under non-growth conditions with H2 as the electron donor and zinc inhibition was quantified as the decrease in the 5 d extent of hematite bioreduction as compared to no-zinc controls. Every NOM was shown to significantly increase zinc inhibition during hematite bioreduction.

A model-based evaluation of sorptive reactivities of hydrous ferric oxide and hematite for U(VI).

The sorption of uranyl onto hydrous ferric oxide (HFO) or hematite was measured by discontinuously titrating the suspensions with uranyl at pH 5.9, 6.8, and 7.

Arsenic removal by iron-modified activated carbon.

Iron-impregnated activated carbons have been found to be very effective in arsenic removal. Oxyanionic arsenic species such as arsenate and arsenite adsorb at the iron oxyhydroxide surface by forming complexes with the surface sites. Our goal has been to load as much iron within the carbon pores as possible while also rendering as much of the iron to be available for sorbing arsenic.