We have observed that high SOD-like function (decomposition of superoxide anion) was observed for several iron(III) compounds with tripodal ligands and several oxovanadium(IV) compounds, and also that these compounds exhibit high catalytic activity for oxidative cleavage of 3,5-di-tert-butylcatechol in non-donating solvents such as dichloromethane or nitromethane. These are suggesting that the ...

Contrary to the cleavage of C−X single bonds, photoreaction C=C bonds electron-rich oxidative alkenes remains a challenge. This work presents novel photoactivation dialkenyl-substituted BODIPY photocages release para-hydroxy benzaldehyde under visible light illumination in an aqueous environment through formal [2+2] cycloaddition singlet oxygen and double bond. A real-time monitoring assay reve...

The events leading to the degradation of the endogenous PrP(C) (normal cellular prion protein) have been the subject of numerous studies. Two cleavage processes, α-cleavage and β-cleavage, are responsible for the main C- and N-terminal fragments produced from PrP(C). Both cleavage processes occur within the N-terminus of PrP(C), a region that is significant in terms of function. α-Cleavage, an ...

The coordination geometry around copper(II) in [Cu(imda)(phen)(H2O)] (1) (H2imda = iminodiacetic acid, phen = 1,10-phenanthroline) is described as distorted octahedral while those in [Cu(imda)(5,6-dmp)] (2) (5,6-dmp = 5,6-dimethyl-1,10-phenanthroline) and [Cu(imda)(dpq)] (3) (dpq = dipyrido-[3,2-d:2',3'-f]-quinoxaline) as trigonal bipyramidal distorted square-based pyramidal with the imda anion...

Sanguinarine is a natural isoquinoline alkaloid derived from the root of Sanguinaria canadensis and from other poppy fumaria species, and is known to have a broad spectrum of pharmacological properties. Here we have found that sanguinarine, at low micromolar concentrations, showed a remarkably rapid killing activity against human melanoma cells. Time-lapse videomicroscopy showed rapid morpholog...

TRPM2 is a Ca(2+)-permeable channel activated by oxidative stress or TNF-alpha, and TRPM2 activation confers susceptibility to cell death. The mechanisms were examined here in human monocytic U937-ecoR cells. This cell line expresses full-length TRPM2 (TRPM2-L) and several isoforms including a short splice variant lacking the Ca(2+)-permeable pore region (TRPM2-S), which functions as a dominant...

Catalytic metallodrugs were used to oxidatively cleave HIV-1 Rev Response Element RNA (RRE RNA), and the mechanisms of RNA cleavage were studied using a combination of matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS), fluorescence spectroscopy, and gel electrophoresis. The metallodrugs, which contained combinations of the transition metals Fe2+, Co2+, ...

The antitumor antibiotic bleomycin has long been believed to exert its therapeutic effects at the level of DNA cleavage. Recently, evidence has been presented to suggest that RNA cleavage may also be important and that one or more transfer RNAs may be involved. To define those tRNAs that may represent important loci for the action of bleomycin, we have fractionated chicken liver tRNAs and ident...

This study reports a novel approach utilizing an octahedral CoII(HAPP)(TFA)2 reagent in the presence of H2O2 with analysis by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) to serve as an efficient probe for bulged DNA structures. Elucidation of DNA bulge-specific recognition pathways and cleavage mechanisms is demonstrated by characterization of bulg...

Members of the carotenoid cleavage dioxygenase family catalyze the oxidative cleavage of carotenoids at various chain positions, leading to the formation of a wide range of apocarotenoid signaling molecules. To explore the functions of this diverse enzyme family, we have used a chemical genetic approach to design selective inhibitors for different classes of carotenoid cleavage dioxygenase. A s...