The Reference Intervals of Hair Trace Element Content in Hereford Cows and Heifers (<Emphasis Type="Italic">Bos taurus</Emphasis>)

Numerous observations suggest a possible connection between the levels of Mg, Zn, Fe, and Zn and the incidence of depressive symptoms. Depression is two to three times more common in women than in men. The menopausal period is extremely conducive to depressive disorders. The aim of this study was to assess the severity of depressive symptoms in postmenopausal women depending on the levels of Mg, Zn, Ca, Cu, and Fe. The study included 198 healthy postmenopausal women at the average age of 56.26 ± 5.55 years. In the first part of the study, standardized research tools were used, namely the Primary Care Evaluation of Mental Disorders (PRIME-MD) and the Beck Depression Inventory (BDI). The second part involved biochemical analysis of Mg, Zn, Ca, Cu, and Fe levels in blood serum. The lowest Cu levels were observed in women without depressive symptoms (1.07 ± 0.22 mg/l) and the highest in those with severe depressive symptoms (1.19 ± 0.17 mg/l), (p ≤ 0.05). The lowest Mg levels were observed in women with depressive symptoms (14.28 ± 2.13 mg/l), and the highest in women without depressive symptoms (16.30 ± 3.51 mg/l), (p ≤ 0.05). The average serum Mg levels (15.75 ± 3.23 mg/l) decreased compared to the reference values (18.77–24 mg/l). What is striking is a potential relation between the levels of Mg and Cu and depressiveness. Our results indicate to a higher vulnerability to depression in a group of women with lower levels of Mg and higher levels of Cu.     

Plant protein hydrolysates as fish fry feed in aquaculture. Hydrolysis of rapeseed proteins by an enzyme complex from king crab hepatopancreas

Rapeseed proteins were processed by an enzyme complex isolated from king crab hepatopancreas in order to obtain a hydrolysate for use as fish fry feed. The amino acid composition of the obtained protein preparation was close to the amino acid composition of fishmeal traditionally used in the production of fish feed. SDS-PAGE, HPLC, and mass spectrometric analysis of the products of enzymatic hydrolysis of rapeseed proteins showed that the proteins were hydrolyzed to a high degree. The composition of the hydrolysates depended on the hydrolysis time and included free amino acids (27% of the total weight of the protein mix after 3 h of hydrolysis and 56% after 21 h of hydrolysis), short peptides (2 to 20 amino acid residues), and small amounts of protein fragments with a molecular weight of approximately 14 kDa, as shown by by SDS-PAG electrophoresis.     

Overexpression of Escherichia coli genes encoding nucleoside phosphorylases in the pET/Bl21(DE3) system yields active recombinant enzymes.

The Escherichia coli genes encoding purine nucleoside phosphorylase, uridine phosphorylase, and thymidine phosphorylase were cloned into pET plasmids to generate highly effective E. coli BL21(DE3) strains producing each of these enzymes. Optimum conditions for biosynthesis of each enzyme as a soluble protein with intact biological activity were found. The crude preparations are approximately 80% pure and can be used immediately for enzymatic transglycosylation. The enzyme preparations were purified to homogeneity by two steps including fractional precipitation with ammonium sulfate and subsequent chromatography on Sephadex G-100 and DEAE-Sephacel.     

Preparative method for obtaining recombinant human interferon α2b from inclusion bodies of <Emphasis Type="Italic">Escherichia coli</Emphasis>

A simple, easily reproducible, and scalable method for obtaining recombinant human interferon α2b from Escherichia coli inclusion bodies has been elaborated. It involves the following steps: preparation of producer cell biomass, isolation and washing of inclusion bodies, their dissolution with protein refolding, SP Sepharose chromatography, and DEAE Sepharose chromatography. According to the results of gel electrophoresis and reversed-phase HPLC, the purity of the protein obtained exceeds 95%.     

Substrate specificity of T5 bacteriophage deoxyribonucleoside monophosphate kinase and its application for the synthesis of [α-<Superscript>32</Superscript>P]d/rNTP

Bacteriophage T5 deoxynucleoside monophosphate kinase (dNMP kinase, EC 2.7.4.13) is shown to catalyze the phosphorylation of both d₂CMP and ribonucleotides AMP, GMP, and CMP, but does not phosphorylate UMP. For natural acceptors of the phosphoryl group, k _m and k _cat were found. The applicability of T5 dNMP kinase as a universal enzyme capable of the phosphorylation of labelled r/dNMP was shown for the synthesis of [α-³²P]rNTP and [α-³²P]dNTP.     

Enzymatic transglycosylation of natural and modified nucleosides by immobilized thermostable nucleoside phosphorylases from Geobacillus stearothermophilus

Natural and modified purine nucleosides have been synthesized using the recombinant thermostable enzymes purine nucleoside phosphorylase II (E. C. 2.4.2.1) and pyrimidine nucleoside phosphorylase (E. C. 2.4.2.2) from Geobacillus stearothermophilus B-2194. The enzymes were produced in recombinant E. coli strains and covalently immobilized on aminopropylsilochrom AP-CPG-170 after heating the cell lysates and the removal of coagulated thermolabile proteins. The resulting preparations of thermostable nucleoside phosphorylases retained a high activity after 20 reuses in nucleoside transglycosylation reactions at 70–75°C with a yield of the target products as high as 96%. Owing to the high catalytic activity, thermal stability, the ease of application, and the possibility of repeated use, the immobilized preparations of thermostable nucleoside phosphorylases are suitable for the production of pharmacologically important natural and modified nucleosides.     

Electrophysical analysis of the damage of Escherichia coli outer membrane

The method of electro-orientational spectroscopy was used to study the damaging action of SDS and Triton X-100 on Escherichia coli cells in which the barrier properties of the outer membrane were impaired by treatment with Triton B (10(-2) M Tris-HCl buffer, pH 8.0) and a heat shock (47 degrees C, 15 min). When either SDS (10(-4)-2.10(-4) M) or Triton X-100 (10(-4)-10(-3) M) was added to such cells, the high-frequency region of their electroorientational spectrum was found to undergo considerable changes. The mode of these changes indicated that the barrier properties of cell cytoplasmic membranes were damaged. These changes were not detected in the case of intact cells. Changes in the low-frequency region of the spectra for intact and damaged cells stemmed from the adsorption of these surfactant molecules on the cell surface.     

Membranes of bacteria and mechanism of action of the antibiotic gramicidin S]

The cyclopeptide antibiotic gramicidin S taken at a concentration of 100--200 mkg/mg membrane protein rapidly increases the permeability of M. lysodeikticus protoplast membranes for substrates of respiratory chain and exogenous cytochromes c. Prolonged incubation of gramicidin S with protoplasts results in their lysis which is more fast at low temperatures. In contrast to natural gramicidin, a derivative of gramicidin S with acetylated amino groups does not inhibit either the micrococcus membrane dehydrogenase or the whole of respiratory chain and does not affect the osmotic barrier of protoplasts. Aliphatic diamines (at concentrations up to 0.1 M) and Ca2+ ions (10(-2) M) do not affect the functioning of the respiratory chain in isolated micrococcus membranes. Another derivative of the antibiotic with an increased distance of loaded amino groups from the cyclopeptide framework (diglycyl gramicidin S) affects the membrane in a way similar to that of natural gramicidin. Washing of gramicidin-treated membranes with NaCl enhances the inhibitory effect of the antibiotic on membrane enzymes. The data obtained suggest that in addition to ionic interactions some hydrophobic interactions also occur during gramicidin S binding to the bacterial membrane, probably at the expense of a hydrophobic peptide ring. It is assumed that gramicidin S, similar to Ca2+ and some other membranotropic agents provides for phase separation of negatively charged phospholipids from other groups of phospholipids, manifesting itself in an appearance of "frozen" sites on the membrane which destroys its barrier properties. This is due to the formation of ionic bonds of negatively charged phospholipids. Simultaneously, unlike Ca2+, gramicidin S, when interacting with membrane proteins, prevents their redistribution in more liquid parts of the membrane, which results in a situation when the respiratory enzymes become surrounded by alkyl chains with restricted motion.     

Current Approaches to the Search of Anxiolytic Drugs

Russian Journal of Bioorganic Chemistry - This article presents a review of studies of new pharmacological substances in the aspect of their anxiolytic activity. These substances are derivatives of...