using uv-vis spectrophotometric method, the formation constant for interaction of fe2+(aq) ion with l-alaninewas experimentally studied at ph = 4.1 ± 0.01 (50mm of potassium hydrogen phthalate buffer), ionic strengthof 0.1m potassium nitrate and at 5 different temperatures 15,20, 25,30 and 35 t. the optical absorption spectraof mixtures containing considered cation and l-alanine were analyzed b...

The steady state kinetic mechanism of the bromide-assisted disproportionation of hydrogen peroxide, forming dioxygen, catalyzed by vanadium bromoperoxidase has been investigated and compared to the mechanism of monochlorodimedone (MCD) bromination under conditions of 0.0125-6 mM H2O2, 1-500 mM Br-, and pH 4.55-6.52. Under these conditions, 50 microM MCD was sufficient to inhibit at least 90% of...

a fragment of histidine rich protein ii (hrp ii 215-236) was investigated by 14n and 17o electric field gradient, efg, tensor calculations using dft. this study is intended to explore the differences between 310-helix and α-helix of hrpii both in the gas phase and in solution. to achieve the aims, the 17o and 14n nqr parameters of a fragment of hrpii (215-236) for both structures are calculated...

PrPC conversion to PrPSc isoform is the main known cause for prion diseases including Crutzfeldt-Jakob, Gerstmann-Sträussler-Sheinker syndrome and fatal familial insomnia in human. The precise mechanism underling this conversion is yet to be well understood. In the present work,  using the coordinate file of PrPC (available on the Protein Data Bank) as a starting structure, separate molecular d...

We used the density functional theory and ab initio pseudopotentials to investigate He–H interaction in crystalline silicon. It was shown that both hydrogen and helium stimulate the formation of vacancy complexes. The presence of hydrogen decreases the vacancy and divacancy formation energies by about 2 eV. The presence of one or two helium atoms reduces the divacancy formation energy by 0.3 an...

The a-helix, first characterized by Linus Pauling in 1951 (Pauling et al., 1951), has been extensively studied due to its prevalence in structural biology (Brandon, 1991). a-Helices are the most common secondary conformation in natural proteins ( 40% of amino acids adopt helical conformations) (Ruan et al., 1990). A typical a-helix completes one rotation with 3.6 amino acid residues, each with ...