Complete genome sequences of 12 bacterial strains from the honey bee gut, resolved with long-read nanopore sequencing.

We report the de novo sequencing of six bacterial strains isolated from the Western honey bee, as well as the resequencing of six strains that have existing draft genomes, to obtain complete, chromosomal-level assemblies. These strains include the bee gut symbiont genera Bartonella, Bifidobacterium, Snodgrassella, Gilliamella, Lactobacillus, and the opportunistic pathogen Serratia marcescens KZ11.

Codeine dysregulates ribosome biogenesis in Escherichia coli with DNA double-strand breaks to chart path to new classes of antibiotics.

Aim: A bacterial genetics-guided approach was utilized for the discovery of new compounds affecting bacterial genome stability. Materials & methods: Fungal extracts and fractions were tested for genome instability-mediated antibacterial activity. Interaction assays and RT-qPCR were used to identify compounds that boost the activity of sub-minimum inhibitory concentration streptomycin and obtain insights on the molecular mechanisms of the primary hit compound, respectively. Results: Several extracts and fractions caused bacterial genome instability. Codeine, in synergy with streptomycin, regulates double-strand break (DSB) repair and causes bacterial ribosome dysfunction in the absence of DSBs, and dysregulation of ribosome biogenesis in a DSB-dependent manner. Conclusion: This study demonstrates a potential viable strategy that we are exploring for the discovery of new chemical entities with activities against Escherichia coli and other bacterial pathogens.

Assessment of chemo-mechanical impacts of CO2 sequestration on the caprock formation in Farnsworth oil field, Texas.

This study evaluates the chemo-mechanical influence of injected CO2 on the Morrow B sandstone reservoir and the upper Morrow shale caprock utilizing data from the inverted 5-spot pattern centered on Well 13-10A within the Farnsworth unit (FWU). This study also seeks to evaluate the integrity of the caprock and the long-term CO2 storage capability of the FWU. The inverted 5-spot pattern was extracted from the field-scale model and tuned with the available field observed data before the modeling work. Two coupled numerical simulation models were utilized to continue the study. First, a coupled hydro-geochemical model was constructed to simulate the dissolution and precipitation of formation minerals by modeling three intra-aqueous and six mineral reactions. In addition, a coupled hydro-geomechanical model was constructed and employed to study the effects of stress changes on the caprock's porosity, permeability, and ground displacement. The Mohr-Coulomb circle and failure envelope were used to determine caprock failure. In this work, the CO2-WAG injection is followed by the historical field-observed strategy. During the forecasting period, a Water Alternating Gas (WAG) injection ratio of 1:3 was utilized with a baseline bottom-hole pressure constraint of 5500 psi for 20 years. A post-injection period of 1000 years was simulated to monitor the CO2 plume and its effects on the CO2 storage reservoir and caprock integrity. The simulation results indicated that the impacts of the geochemical reactions on the porosity of the caprock were insignificant as it experienced a decrease of about 0.0003% at the end of the 1000-year post-injection monitoring. On the other hand, the maximum stress-induced porosity change was about a 1.4% increase, resulting in about 4% in permeability change. It was estimated that about 3.3% of the sequestered CO2 in the formation interacted with the caprock. Despite these petrophysical property alterations and CO2 interactions in the caprock, the caprock still maintained its elastic properties and was determined to be far from its failure.

The interaction energies of cholesterol and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine in spread mixed monolayers at the air-water interface.

The interaction of cholesterol with 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) was investigated in insoluble miscible mixed monolayers at the air-water interface using a Langmuir balance technique. The strong condensation effects observed at all compositions were quantified on the basis of excess thermodynamic properties of the system. It was found that partial molar areas and work of compression of cholesterol in the mixed monolayers were greatly reduced and increased, respectively, at xDOPE of 0.8, while, in accord with the "umbrella model", the character of cholesterol monolayers was drastically affected even at mole fractions of DOPE as low as 0.2. Calculated Gibbs free energies of mixing were shown to be symmetric about equimolar lipid quantities and considerably decreased at high surface pressures. Interaction energy parameters calculated from values of excess Gibbs energy are found to decrease linearly with surface pressure at a rate of 100 kT m.N(-1), regardless of composition. All evidence points out that cholesterol-DOPE molecular interactions can be adequately simulated using a simple regular mixture model.