The V Congress of the Russian Psychological Society

This paper summarizes the organizational and scientific outcomes of the 5th Congressof the Russian Psychological Society. It shows the RPS’s dynamics of developmentsince its establishment to the present day, and presents a report on theCongress’s major events, and the statistics in comparison with the other eventsof international scientific life. Scientific sections of the Congress are grouped thatallowed to showing the main trends in modern psychology. The new directionsof psychological research debuted on the Congress are shown, the most importantdomains of the psychological science are highlighted, and possible reasonsfor some of them not having succeeded are given. The new subjects and objectsof psychological studies new to psychologists are identified. Based on the historicalview of the contemporary psychology, were analyzed the future directions ofits development

Enzyme Substrate Complex of the H200C Variant of Homoprotocatechuate 2,3-Dioxygenase: Mössbauer and Computational Studies

The extradiol, aromatic ring-cleaving enzyme homoprotocatechuate 2,3-dioxygenase (HPCD) catalyzes a complex chain of reactions that involve second sphere residues of the active site. The importance of the second-sphere residue His200 was demonstrated in studies of HPCD variants, such as His200Cys (H200C), which revealed significant retardations of certain steps in the catalytic process as a result of the substitution, allowing novel reaction cycle intermediates to be trapped for spectroscopic characterization. As the H200C variant largely retains the wild-type active site structure and produces the correct ring-cleaved product, this variant presents a valuable target for mechanistic HPCD studies. Here, the high-spin Fe^II states of resting H200C and the H200C–homoprotocatechuate enzyme–substrate (ES) complex have been characterized with Mössbauer spectroscopy to assess the electronic structures of the active site in these states. The analysis reveals a high-spin Fe^II center in a low symmetry environment that is reflected in the values of the zero-field splitting (ZFS) (<i>D</i> ≈ – 8 cm^–1, <i>E</i>/<i>D</i> ≈ 1/3 in ES), as well as the relative orientations of the principal axes of the ⁵⁷Fe magnetic hyperfine (<b>A</b>) and electric field gradient (EFG) tensors relative to the ZFS tensor axes. A spin Hamiltonian analysis of the spectra for the ES complex indicates that the magnetization axis of the integer-spin <i>S</i> = 2 Fe^II system is nearly parallel to the symmetry axis, <i>z</i>, of the doubly occupied d_<i>xy</i> ground orbital deduced from the EFG and <b>A</b>-values, an observation, which cannot be rationalized by DFT assisted crystal-field theory. In contrast, ORCA/CASSCF calculations for the ZFS tensor in combination with DFT calculations for the EFG- and <b>A</b>-tensors describe the experimental data remarkably well

Assessment of microcrystal quality by transmission electron microscopy for efficient serial femtosecond crystallography

Serial femtosecond crystallography (SFX) employing high-intensity X-ray free-electron laser (XFEL) sources has enabled structural studies on microcrystalline protein samples at non-cryogenic temperatures. However, the identification and optimization of conditions that produce well diffracting microcrystals remains an experimental challenge. Here, we report parallel SFX and transmission electron microscopy (TEM) experiments using fragmented microcrystals of wild type (WT) homoprotocatechuate 2,3-dioxygenase (HPCD) and an active site variant (H200Q). Despite identical crystallization conditions and morphology, as well as similar crystal size and density, the indexing efficiency of the diffraction data collected using the H200Q variant sample was over 7-fold higher compared to the diffraction results obtained using the WT sample. TEM analysis revealed an abundance of protein aggregates, crystal conglomerates and a smaller population of highly ordered lattices in the WT sample as compared to the H200Q variant sample. While not reported herein, the 1.75&nbsp;Å resolution structure of the H200Q variant was determined from ∼16&nbsp;min of beam time, demonstrating the utility of TEM analysis in evaluating sample monodispersity and lattice quality, parameters critical to the efficiency of SFX experiments

Assessment of microcrystal quality by transmission electron microscopy for efficient serial femtosecond crystallography

Serial femtosecond crystallography (SFX) employing high-intensity X-ray free-electron laser (XFEL) sources has enabled structural studies on microcrystalline protein samples at non-cryogenic temperatures. However, the identification and optimization of conditions that produce well diffracting microcrystals remains an experimental challenge. Here, we report parallel SFX and transmission electron microscopy (TEM) experiments using fragmented microcrystals of wild type (WT) homoprotocatechuate 2,3-dioxygenase (HPCD) and an active site variant (H200Q). Despite identical crystallization conditions and morphology, as well as similar crystal size and density, the indexing efficiency of the diffraction data collected using the H200Q variant sample was over 7-fold higher compared to the diffraction results obtained using the WT sample. TEM analysis revealed an abundance of protein aggregates, crystal conglomerates and a smaller population of highly ordered lattices in the WT sample as compared to the H200Q variant sample. While not reported herein, the 1.75 Å resolution structure of the H200Q variant was determined from ~16 minutes of beam time, demonstrating the utility of TEM analysis in evaluating sample monodispersity and lattice quality, parameters critical to the efficiency of SFX experiments

A Long-Lived Fe^III-(Hydroperoxo) Intermediate in the Active H200C Variant of Homoprotocatechuate 2,3-Dioxygenase: Characterization by Mössbauer, Electron Paramagnetic Resonance, and Density Functional Theory Methods

The extradiol-cleaving dioxygenase homoprotocatechuate 2,3-dioxygenase (HPCD) binds substrate homoprotocatechuate (HPCA) and O₂ sequentially in adjacent ligand sites of the active site Fe^II. Kinetic and spectroscopic studies of HPCD have elucidated catalytic roles of several active site residues, including the crucial acid–base chemistry of His200. In the present study, reaction of the His200Cys (H200C) variant with native substrate HPCA resulted in a decrease in both <i>k</i>_cat and the rate constants for the activation steps following O₂ binding by >400 fold. The reaction proceeds to form the correct extradiol product. This slow reaction allowed a long-lived (<i>t</i>_1/2 = 1.5 min) intermediate, H200C-HPCA_Int1 (<i>Int1</i>), to be trapped. Mössbauer and parallel mode electron paramagnetic resonance (EPR) studies show that <i>Int1</i> contains an <i>S</i>₁ = 5/2 Fe^III center coupled to an <i>S</i>_R = 1/2 radical to give a ground state with total spin <i>S</i> = 2 (<i>J</i> > 40 cm^–1) in Hexch=JŜ1·ŜR. Density functional theory (DFT) property calculations for structural models suggest that <i>Int1</i> is a (HPCA semiquinone^•)­Fe^III(OOH) complex, in which OOH is protonated at the distal O and the substrate hydroxyls are deprotonated. By combining Mössbauer and EPR data of <i>Int1</i> with DFT calculations, the orientations of the principal axes of the ⁵⁷Fe electric field gradient and the zero-field splitting tensors (<i>D</i> = 1.6 cm^–1, <i>E</i>/<i>D</i> = 0.05) were determined. This information was used to predict hyperfine splittings from bound ¹⁷OOH. DFT reactivity analysis suggests that <i>Int1</i> can evolve from a ferromagnetically coupled Fe^III-superoxo precursor by an inner-sphere proton-coupled-electron-transfer process. Our spectroscopic and DFT results suggest that a ferric hydroperoxo species is capable of extradiol catalysis

Chemical and pharmacological study of herbal preparations that improve cognitive-mnestic functions

Decoctions of two herbal mixtures including Filipendula ulmaria (L.) Maxim. (meadowsweet), Vaccinium myrtillus L. (bilberry), and shoot and green leaves of Bergenia crassifolia (L.) Fritsch. (badan) were found to improve cognitive-mnestic functions and normalize conditioned reflex activity and explorative behavior of animals after hypoxic exposure. The decoction of mixture II containing mainly meadowsweet was most active at a dose of 5 mL/kg. The quantitative contents of flavonoids calculated as rutin in decoctions of mixtures I and II were (0.22 ± 0.007) and (0.36 ± 0.011) mg/mL, respectively. A total of 22 elements were detected in ash of mixture II and its potent decoction, including 15 essential or conditionally essential ones. Mixture II contained primarily K, Ca, Na, Mg, Si, P, Fe, and Mn; its decoction; Ca, Mg, K, Na, P, Si, Mn, and Zn. The accumulation in the decoction of high concentrations of B, P, Mg, and Mo was noteworthy

Chemical and pharmacological study of herbal preparations that improve cognitive-mnestic functions

Decoctions of two herbal mixtures including Filipendula ulmaria (L.) Maxim. (meadowsweet), Vaccinium myrtillus L. (bilberry), and shoot and green leaves of Bergenia crassifolia (L.) Fritsch. (badan) were found to improve cognitive-mnestic functions and normalize conditioned reflex activity and explorative behavior of animals after hypoxic exposure. The decoction of mixture II containing mainly meadowsweet was most active at a dose of 5 mL/kg. The quantitative contents of flavonoids calculated as rutin in decoctions of mixtures I and II were (0.22 ± 0.007) and (0.36 ± 0.011) mg/mL, respectively. A total of 22 elements were detected in ash of mixture II and its potent decoction, including 15 essential or conditionally essential ones. Mixture II contained primarily K, Ca, Na, Mg, Si, P, Fe, and Mn; its decoction; Ca, Mg, K, Na, P, Si, Mn, and Zn. The accumulation in the decoction of high concentrations of B, P, Mg, and Mo was noteworthy