Controllable mullite bismuth ferrite micro/nanostructures with multifarious catalytic activities for switchable/hybrid catalytic degradation processes.

In this work, controllable preparation of micro/nanostructured bismuth ferrites (BFOs) were used to investigate multifarious heterogeneous catalyses, including Fenton/Fenton-like reaction, photocatalysis, photo-Fenton oxidation, and peroxymonosulfate (PMS) activation. Results showed that BFO can be used asa novel catalyst to activate switchable catalytic degradation of organic matters. Additionally, a novel catalytic system for degradation of organic pollutants, which integrating all-above heterogeneous catalyses is denoted as BFO/HO/PMS hybrid reaction, is introduced for the first time.

Radical S-adenosylmethionine (SAM) enzymes in cofactor biosynthesis: a treasure trove of complex organic radical rearrangement reactions.

In this minireview, we describe the radical S-adenosylmethionine enzymes involved in the biosynthesis of thiamin, menaquinone, molybdopterin, coenzyme F420, and heme. Our focus is on the remarkably complex organic rearrangements involved, many of which have no precedent in organic or biological chemistry.

Monitoring protein-small molecule interactions by local pH modulation.

We have developed a technique for sensing protein-small molecule and protein-ion interactions in bulk aqueous solution by utilizing a pH sensitive dye, 5-(and-6)-carboxyfluorescein, conjugated to free lysine residues on the surfaces of designated capture proteins. The fluorescein intensity was found to change by about 6% and 15% for small molecule and ion binding, respectively. The assay works by modulating the local electric fields around a pH sensitive dye.

Polyamide recognition-mass spectrometry for distinguishing hairpin DNA from coil DNA.

The discrimination between hairpin DNA and coil DNA has been well achieved through polyamides as probes by electrospray ionization (ESI) mass spectrometry. ESI mass spectra showed that polyamides bind to hairpin DNA with high selectivity, and almost no binding with coil DNA. In addition, the noncovalent interaction between polyamides and hairpin DNA was also studied; the results show that hairpin DNA with longer stem and polyamides with more heterocycles have higher binding affinity and stability in gas phase.

Discrimination of cyclic peptide diastereomers by electrospray ionization tandem mass spectrometry.

In this research, the characteristic ions' abundance ratio between two isomers A and B in MS/MS mass spectra was defined as a parameter for discriminating diastereomers. Through this ratio, the discrimination of four pairs of cyclic peptide (CP) diastereomers was successfully achieved. Furthermore, in the analysis of diastereomers' mixtures, both calibration curve and calculational methods were substantiated to have high precision and accuracy.

[Study on HPLC fingerprint of Trachelospermum jasminoides].

Objective: To establish HPLC fingerprint for identification and evaluation of the quality of Trachelospermum jasminoides.

Method: The analysis was performed on a ZORBAX Eclipse XDB-C18 analytical column (4.6 mm x 150 mm, 5 microm) with H2O (A) and methanol (B) as mobile phases in gradient mode.

Spectroscopy probing of the formation, recognition, and conversion of a G-quadruplex in the promoter region of the bcl-2 oncogene.

This study has demonstrated the formation of the G-quadruplex structure from the G-rich sequence in the promoter region of the bcl-2 oncogene; the formation could be induced by addition of NH(4)(+) or K(+) ions. The binding affinity and stoichiometry of seven small molecules with the G-quadruplex were examined by using ESI-MS, as well as CD and UV spectroscopy. The binding-affinity order was determined to be P1 approximately = P5 > P2 > P3 approximately = P4 > P7 > P6.