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Abstract Saprolegnia parasiticais an oomycete pathogen responsible for saprolegniasis diseases that result in large production losses in the catfish and salmon aquaculture industry. The use of copper sulfate as an anti-Saprolegnia treatment has been reported as an alternative to malachite green, formaldehyde and hydrogen peroxide treatment methods. The current study investigates a new strategy to inhibitSaprolegnia parasiticagrowth by combining copper and ionophores at low levels. The chemical agents tetraethylthiuram disulfide (TDD), ciclopirox olamine (CLP), 2-mercaptopyridine N-oxide (MPO), 5-chloro-8-hydroxy-7-iodoquinoline (CHI), 5,7-dichloro-8-hydroxyquinoline (DHQ) and 8-Quinolinol (8QN) were identified to inhibitS. parasiticagrowth in a copper-dependent manner. At concentrations below the lethal dose of individual ionophore, increasing copper concentrations resulted in synergeticS. parasiticagrowth inhibition. The addition of the exogenous copper chelator bathocuproine sulfate (BCS), reversed the inhibition ofS. parasiticagrowth by TDD, CLP, MPO, and 8QN but not CHI and DHQ. Our data demonstrates that ionophores, in combination with low levels of copper, can effectively limitS. parasiticagrowth both in a liquid and solid support growth environment. Investigations into the underlying mechanism of Cu-ionophore toxicity are discussed. 

This study identified the LARP6 La Module from Tetrabaena socialis (T. socialis), a four-celled green algae, in an effort to better understand the evolution of LARP6 structure and RNA-binding activity in multicellular eukaryotes. Using a combination of sequence alignments, domain boundary screens, and structural modelling, we recombinantly expressed and isolated the TsLARP6 La Module to > 98% purity for in vitro biochemical characterization. The La Module is stably folded and exerts minimal RNA binding activity against single-stranded homopolymeric RNAs. Surprisingly, it exhibits low micromolar binding affinity for the vertebrate LARP6 cognate ligand, a bulged-stem loop found in the 5'UTR of collagen type I mRNA, but does not bind double-stranded RNAs of similar size. These result suggests that the TsLARP6 La Module may prefer structured RNA ligands. In contrast, however, the TsLARP6 La Module does not exhibit the RNA chaperone activity that is observed in vertebrate homologs. Therefore, we conclude that protist LARP6 may have both distinct RNA ligands and binding mechanisms from the previously characterized LARP6 proteins of animals and vascular plants, thus establishing a distinct third class of the LARP6 protein family. 

Iron diimine dications have distinct lability and redox properties. Our study of ion-pairing, dissociation and redox lets us evaluate the robustness of the dications and their respective monocations, which are key photocatalytic intermediates. 

Azobenezene compounds are putative solar thermal fuels (STF) due to excellent photostability and structural control of isomerization rates.  Azobenzenes in which both Z‐ and E‐isomers are liquid at room temperature are promising candidates for STF flow technology.  A literature survey of melting points led to the synthesis and isomer separation of ortho‐ and meta‐substituted, monofunctional azobenzenes with fluoro, methyl, ethyl, trifluoromethyl and methoxy substituents.  Four of the compounds are liquid azobenzenes with higher energy density than literature work with higher molar mass, liquid compounds.  Eight of the compounds unexpectedly displayed a higher melting point for the Z‐isomer which is rarely observed.  The higher‐melting behavior is explained, in part, by intermolecular close contacts in the Z‐isomer packing lattice.