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A non-isocyanate synthetic route was used to generate 20 different ionic liquids containing either a carbamate or thiocarbamate functional group. 

ABSTRACT Development of genome-editing tools in diverse microbial species is an important step both in understanding the roles of those microbes in different environments, and in engineering microbes for a variety of applications. Freshwater-specific clades of Actinobacteria are ubiquitous and abundant in surface freshwaters worldwide. Here, we show thatRhodoluna lacicolaandAurantimicrobium photophilum, which represent widespread clades of freshwater Actinobacteria, are naturally transformable. We also show that gene inactivation via double homologous recombination and replacement of the target gene with antibiotic selection markers can be used in both strains, making them convenient and broadly accessible model organisms for freshwater systems. We further show that in both strains, the predicted phytoene synthase is the only phytoene synthase, and its inactivation prevents the synthesis of all pigments. The tools developed here enable targeted modification of the genomes of some of the most abundant microbes in freshwater communities. These genome-editing tools will enable hypothesis testing about the genetics and (eco)physiology of freshwater Actinobacteria and broaden the available model systems for engineering freshwater microbial communities. IMPORTANCETo advance bioproduction or bioremediation in large, unsupervised environmental systems such as ponds, wastewater lagoons, or groundwater systems, it will be necessary to develop diverse genetically amenable microbial model organisms. Although we already genetically modify a few key species, tools for engineering more microbial taxa, with different natural phenotypes, will enable us to genetically engineer multispecies consortia or even complex communities. Developing genetic tools for modifying freshwater bacteria is particularly important, as wastewater, production ponds or raceways, and contaminated surface water are all freshwater systems where microbial communities are already deployed to do work, and the outputs could potentially be enhanced by genetic modifications. Here, we demonstrate that common tools for genome editing can be used to inactivate specific genes in two representatives of a very widespread, environmentally relevant group of Actinobacteria. These Actinobacteria are found in almost all tested surface freshwater environments, where they co-occur with primary producers, and genome-editing tools in these species are thus a step on the way to engineering microbial consortia in freshwater environments. 

We previously demonstrated that osmium tetroxide and TMEDA generate stable crystalline adducts with alkenes that facilitate X-ray analysis and structure assignments. Alternatively, osmate esters can be prepared from diols, potassium osmate, and TMEDA·2TsOH in a nonoxidative condensation reaction. This new approach provides a convenient route to form stable, crystalline osmate(VI) esters for X-ray analysis. Because it is redox neutral, it works with a variety of diol substrates, including 1,3-diols, that cannot be prepared from alkenes. α-Hydroxy acids also form stable osmate esters in reasonable yields and readily crystallize. An alternative ligand screen was performed to assess the improved crystallinity from substituted TMEDA analogues. The enhanced crystallinity of osmate esters and the incorporation of a heavy atom make a reliable determination of structure and absolute configuration routine. 

Distinguishing ET and PCET processes is challenging. This paper used “protein charge ladders” to show that PCET occurs at the non-redox “structural” zinc sight of SOD1, when a Cu ion displaces Zn. 

We explore the properties of interferometric data from high-redshift 21 cm measurements using the Murchison Widefield Array (MWA). These data contain the redshifted 21 cm signal, contamination from continuum foreground sources, and radiometric noise. The 21 cm signal from the Epoch of Reionization (EoR) is expected to be highly Gaussian, which motivates the use of the power spectrum as an effective statistical tool for extracting astrophysical information. We find that foreground contamination introduces non-Gaussianity into the distribution of measurements and then use this information to separate Gaussian from the non-Gaussian signal. We present improved upper limits on the 21 cm EoR power spectrum from the MWA using a Gaussian component of the data, based on the existing analysis from C. D. Nunhokee et al. 2025. This is extracted as the best-fitting Gaussian to the measured data. Our best 2σ (thermal+sample variance) limit for 268 hr of data improves from (30.2 mK)2 to (23.0 mK)2 at z = 6.5 for the East–West polarization, and from (39.2 mK)2 to (21.7 mK)2 = 470 mK2 in North–South. The best limits at z = 6.8 (z = 7.0) improve to P < (25.9 mK)2 (P < (32.0 mK)2) and k = 0.18h Mpc‑1 (k = 0.21h Mpc‑1). Results are compared with realistic simulations, which indicate that leakage from foreground contamination is a source of the non-Gaussian behavior. 

A cellulose graft copolymer (cellulose nanoresin) was synthesized by the all-aqueous functionalization of cellouronic acid with poly (vinyl benzyl trimethyl ammonium chloride) (poly(vbTMAC)). Cellulose was oxidized using the highly reported 2,2,6,6-tetramethylpiperidine-1-oxy radical (TEMPO)-mediated selective C-6 oxidation reaction. Fischer–Speier esterification of cellouronic acid was used to graft poly(vbTMAC) to the cellulosic backbone in a facile click-like mechanism. Synthesis of cellulose nanoresin was confirmed using dynamic light scattering and zeta potential measurements. Conductometric titration was used to determine the carboxylate content of cellouronic acid and the percent functionalization of the cellulose nanoresin, which was 1.69 ± 0.03 mmol/g and 61.2 ± 4%, respectively. Using a disodium fluorescein (NaFL) surrogate adsorbate, the maximum adsorption capacity of CNR was measured to be 26.8 ± 1.3 mg NaFL per gram of CNR with a Langmuir equilibrium binding constant of Ks = 10.5 ± 2 ppm−1. When examined as a thin film membrane, a breakthrough study of CNR showed that equilibrium loading was achieved in less than 30 s, and that > 90% of loading occurred in under 5 s. This data suggests that these films can be used as contact resins for anion-exchange water purification. We show in this work that these films maintain > 99% of loading performance over 40 trials of regeneration and reuse, meaning that these films are green and regenerable. Initial testing shows that CNR is effective at the removal of perfluorooctane sulfonate (PFOS) from water to below our limit of detection of 100 ppt. 

Abstract The synthesis and characterization of a series of polyurethane ionenes using a non‐isocyanate approach is disclosed. Imidazole‐capped, urethane‐containing prepolymers are prepared by first reacting carbonyl diimidazole (CDI) with several poly(propylene glycol) (PPG) diols with variable molecular weight, followed by subsequent reaction with 3‐aminopropylimidazole (API). Polymerization with 1,4‐dibromomethylbenzene followed by anion exchange resulted in the desired polyurethane ionenes bearing the [NTf₂] counteranion as a series of viscous liquids. NMR and FTIR spectroscopy are used to characterize the intermediates and final ionenes, including molecular weight determination by end‐group analysis. A single glass transition temperature (T_g), as determined by differential scanning calorimetry (DSC), is observed for each ionene (−38 to −64 °C) with theT_gdecreasing with increasing PPG molecular weight. Thermogravimetric analysis (TGA) indicated a two‐step decomposition for each ionene, with the first being degradation of the PPG segment, followed by the urethane/ionic segment. Microphase separation is observed from x‐ray scattering profiles with Bragg distances that increased with increasing PPG molecular weight. Ionic conductivity is found to be inversely dependent upon DSCT_gat lower temperatures (RT and below); however, at higher temperatures, conductivity appears to be more dependent upon the ability of ionic aggregates caused by phase separation to interact.