Metatranscriptome of an anaerobic benzene-degrading, nitrate-reducing enrichment culture reveals involvement of carboxylation in benzene ring activation.

The enzymes involved in the initial steps of anaerobic benzene catabolism are not known. To try to elucidate this critical step, a metatranscriptomic analysis was conducted to compare the genes transcribed during the metabolism of benzene and benzoate by an anaerobic benzene-degrading, nitrate-reducing enrichment culture. RNA was extracted from the mixed culture and sequenced without prior mRNA enrichment, allowing simultaneous examination of the active community composition and the differential gene expression between the two treatments.

Effect of humidity on lung surfactant films subjected to dynamic compression/expansion cycles.

The surface activity of bovine lipid extracted surfactant (BLES) preparations used in surfactant replacement therapy is studied in dynamic film compression/expansion cycles as a function of relative humidity, surfactant concentration, compression rate, and compression periodicity. BLES droplets were formed in a constrained sessile droplet configuration (CSD). Images obtained during cycling were analyzed using axisymmetric drop shape analysis (ADSA) to yield surface tension, surface area, and drop volume data.

Effect of humidity on the adsorption kinetics of lung surfactant at air-water interfaces.

The in vitro adsorption kinetics of lung surfactant at air-water interfaces is affected by both the composition of the surfactant preparations and the conditions under which the assessment is conducted. Relevant experimental conditions are surfactant concentration, temperature, subphase pH, electrolyte concentration, humidity, and gas composition of the atmosphere exposed to the interface. The effect of humidity on the adsorption kinetics of a therapeutic lung surfactant preparation, bovine lipid extract surfactant (BLES), was studied by measuring the dynamic surface tension (DST).