The electron transfer (ET) from bacteriopheophytin (H) to ubiquinone (UQ) in the photosynthetic reaction center (PSRC) of Rhodopseudomonas (Rps.) viridis was studied by ab initio quantum-chemical calculations. The ET from the H in L-region (HL) to menaquinone (MQ) occurs through the super-exchange mechanism using Trp M250 as a bridge, while in the M-region Leu L189 works as a bridge in the ET f...

The secondary quinone anion radical QB(-) (SQB) in reaction centers of Rhodobacter sphaeroides interacts with Nδ of His-L190 and Np (peptide nitrogen) of Gly-L225 involved in hydrogen bonds to the QB carbonyls. In this work, S-band (∼3.6 GHz) ESEEM was used with the aim of obtaining a complete characterization of the nuclear quadrupole interaction (nqi) tensors for both nitrogens by approaching...

although economists and entrepreneurs had been aware of the impact of economies of scale on average cost, no comprehensive theory was introduced until 1950s. economies of scale is used by economist as a practical measure for evaluating the extent of competition (monopoly) in real markets. there are two primary aims of this paper: 1) to introduce theoretical aspects of economies of scale, 2) to ...

We recently discovered that MG53, a muscle-specific tripartite motif (TRIM) family protein, functions as a sensor of oxidation to nucleate the assembly of cell membrane repair machinery. Our data showed that disulfide bond formation mediated by Cys242 is critical for MG53-mediated translocation of intracellular vesicles toward the injury sites. Here we test the hypothesis that leucine zipper mo...

DNA shuffling and saturation mutagenesis of positions F108, L190, I219, D235, and C248 were used to generate variants of the epoxide hydrolase of Agrobacterium radiobacter AD1 (EchA) with enhanced enantioselectivity and activity for styrene oxide and enhanced activity for 1,2-epoxyhexane and epoxypropane. EchA variant I219F has more than fivefold-enhanced enantioselectivity toward racemic styre...

The electron-transfer reactions involving the quinones in the bacterial photosynthetic reaction center (bRC) are coupled to a proton uptake by the bRC. In this study, we calculated the energies of the different states of the bRC occurring during these electron-transfer and protonation reactions by an electrostatic model. We considered the possibility that titratable groups of the bRC can change...