Bacillus subtilis has been shown to express a cytosolic oxalate decarboxylase (EC 4.1.1.2). The enzyme was induced in acidic growth media, particularly at pH 5.0, but not by oxalate. The enzyme was purified, and N-terminal sequencing identified the protein to be encoded by yvrK. The role of the first oxalate decarboxylase to be identified in a prokaryote is discussed.

Nano-TaOx particles were supported on multi-walled carbon nanotubes via the thermal decomposition of oxy-tantalum phthalocyanine. The phthalocyanine-derived carbon connected TaOx particles with the nanotube-support to provide a conductive path. The oxygen reduction reaction activity, which solely originated from TaOx, was above 0.9 V with larger currents than conventional TaOx particles in acid...

Monodispersed nickel phosphide (Ni2P) nanoparticles were for the first time applied to photocatalytic hydrogen evolution from lactic acid aqueous solution under visible light LED irradiation using CdS nanorods as a photosensitizer. The system exhibited high photocatalytic hydrogen-generating activity and excellent stability in aqueous acidic media.

The macrocyclic amine, 1,5,9,18,22,26-hexaaza [11.11]-p-cyclophane (1) contains two dipropylenetriamine units which make the molecule highly basic. Owing to this basicity, 1 can be highly protonated in acidic media and can form supramolecular assemblies with different anions. Two new supramolecular structures arise from self-assembly of the salt of 1 with fumaric acid and of the N-methyl deriva...

Highly ordered three-dimensional Im3m-type periodic mesoporous organosilica with a cavity size of 9.8 nm has been synthesized under strongly acidic media in the presence of inorganic salts using triblock copolymer F127 as the template and 1,2-bis(trimethoxysilyl)ethane as the organically bridged silica source.

Human telomerase reverse transcriptase (hTERT) is upregulated in most cancer cell types as well in immortalized cells. The underlying mechanism for such upregulation, however, remains largely unknown. We report here that bile acids under acidified media increase hTERT expression via c-myc activation in primary human gastric cancer cell lines. Human gastric cancer MKN28, MGC803 and SGC7901 cells...

The objective of this study was to investigate the insulin incorporation and release properties of poly(methacrylic acid-g-ethylene glycol) P(MAA-g-EG) microparticles as a function of copolymer composition. These microparticles exhibited unique pH-responsive characteristics in which interpolymer complexes were formed in acidic media and dissociated in neutral/basic environments. The micropartic...

10,11-Didehydroquinine is a simple, low molecular weight supergelator which forms, in nonpolar media, stable chiral organogels composed of unique double-helix nano-sized fibers. A novel gelation mechanism involves a hydrogen bonding network formed by an acidic alkyne proton of the Cinchona gelator and the carbonyl group of ethyl acetate used as a solvent.

Monoclinic HfO2 nanoparticles were doped with nitrogen via hydrothermal treatment that avoided high-cost pyrolysis with NH3 gas in order to develop a novel oxygen reduction reaction catalyst for use in acidic media. Catalyst size reduction was achieved using a reduced graphene oxide support, and activity above 0.8 V was obtained.

The dissolution behavior of enamel and synthetic hydroxyapatite in acidic media possessing a high degree of partial saturation was found to be neither simple surface dissolution nor linear with time. Instead, a repetitive, stepwise dissolution pattern was observed. To explain this phenomenon, a model based upon a hypothesis that the crystals dissolve in a synchronized fashion was proposed.