Partially reduced oxygen species (PROS), produced by reduced heme bound Aβ peptides, can cause oxidative stress and synaptic damage in the brain, which is one of the key pathological features of Alzheimer's disease. In situ oxidation of the heme center by a physiological redox agent like Cytochrome c (Cyt c) can significantly suppress neurotoxic PROS formation. Thus, Cyt c can potentially act a...

To investigate protein folding dynamics in terms of compactness, we developed a continuous-flow mixing device to make small-angle x-ray scattering measurements with the time resolution of 160 micros and characterized the radius of gyration (R(g)) of two folding intermediates of cytochrome c (cyt c). The early intermediate possesses approximately 20 A of R(g), which is smaller by approximately 4...

In crystals of the key respiratory and photosynthetic electron transfer protein called ubihydroquinone:cytochrome (cyt) c oxidoreductase or cyt bc(1), the extrinsic [2Fe2S] cluster domain of its Fe-S subunit assumes several conformations, suggesting that it may move during catalysis. Herein, using Rhodobacter capsulatus mutants that have modifications in the hinge region of this subunit, we wer...

Generally, a protein molecule should form its native structure to perform its biological function in the living cell. However, the failure of proper folding, i.e. misfolding, occurs occasionally and this causes aggregation and/or degradation of the protein, which is potentially linked to protein mis-folding diseases, e.g. prion disease and Parkinson's disease. Therefore, it is critical to under...

The use of non-mammalian model organisms, including yeast Saccharomyces cerevisiae, can provide new insights into eukaryotic PCD (programmed cell death) pathways. In the present paper, we report recent achievements in the elucidation of the events leading to PCD that occur as a response to yeast treatment with AA (acetic acid). In particular, ROS (reactive oxygen species) generation, cyt c (cyt...

We investigated the effect of short-term changes in temperature on alternative (Alt) and cytochrome (Cyt) pathway respiration, both in intact tissues and isolated mitochondria of 14-d-old cotyledons of soybean (Glycine max L. cv Stevens). We also established the extent to which temperature alters the interaction between the oxidizing pathways and the level of ubiquinone (UQ) reduction (UQ(r)/UQ...

To test the significance of ultrafast protein folding signals (<<1 msec), we studied cytochrome c (Cyt c) and two Cyt c fragments with major C-terminal segments deleted. The fragments remain unfolded under all conditions and so could be used to define the unfolded baselines for protein fluorescence and circular dichroism (CD) as a function of denaturant concentration. When diluted from high to ...

A programmed drug delivery system that can achieve sequential release of multiple therapeutics under different stimulus holds great promise to enhance the treatment efficacy and overcome multi-drug resistance (MDR) in tumor. Herein, multi-organelle-targeted and pH/ cytochrome c (Cyt c) dual-responsive nanoparticles were designed for combination therapy on resistant tumor. In this system (design...

Two new Ru-modified, Zn-substituted derivatives of horse heart cytochrome c have been prepared, Rua,L(histi* dine-33)-Zn-cyt c (a = NH3; L = pyridine, isonicotinamide). Molecular mechanics modeling indicates that the 11.7 A edge-to-edge separation between the redox centers is virtually identical with that reported for the Ru-pentaammine derivative. Rates of photoinduced charge separation and re...

Herein, chitosan (CS) fibers coated with TEMPO-oxidized cellulose nanofibers (CS/TOCN fibers) were successfully prepared using a wet spinning technique; CS was dissolved in acetic acid to obtain doping solution. The tensile strength and ammonia adsorption percentages increased increasing TOCN concentration. maximum percentage (41.39%, 8.3 mg/g) obtained when 2% NaOH 0.01% used as the coagulatio...