On the utility of predictive chromatography to complement mass spectrometry based intact protein identification

The amino acid sequence determines the individual protein three-dimensional structure and its functioning in an organism. Therefore, "reading" a protein sequence and determining its changes due to mutations or post-translational modifications is one of the objectives of proteomic experiments. The commonly utilized approach is gradient high-performance liquid chromatography (HPLC) in combination with tandem mass spectrometry. While serving as a way to simplify the protein mixture, the liquid chromatography may be an additional analytical tool providing complementary information about the protein structure. Previous attempts to develop "predictive" HPLC for large biomacromolecules were limited by empirically derived equations based purely on the adsorption mechanisms of the retention and applicable to relatively small polypeptide molecules. A mechanism of the large biomacromolecule retention in reversed-phase gradient HPLC was described recently in thermodynamics terms by the analytical model of liquid chromatography at critical conditions (BioLCCC). In this work, we applied the BioLCCC model to predict retention of the intact proteins as well as their large proteolytic peptides separated under different HPLC conditions. The specific aim of these proof-of-principle studies was to demonstrate the feasibility of using "predictive" HPLC as a complementary tool to support the analysis of identified intact proteins in top-down, middle-down, and/or targeted selected reaction monitoring (SRM)-based proteomic experiments

ВОЛОКНИСТІ ІОНІТИ ФІБАН ЯК СОРБЕНТИ СПОЛУК УРАНУ (VI), ПРИСУТНІХ У СУЛЬФАТНИХ РОЗЧИНАХ

Some regularities of Uranium(VI) compounds sorption recovery from model sulfate solutions by fibrous ion exchangers FIBAN C-1 (strongly acidic cation exchanger with -SO3H groups), FIBAN AC-22V (polyampholyte with amino- and carboxyl groups) and FIBAN A-6 (anion exchanger with strongly basic and weakly basic aminogroups) under dynamic conditions were established. It was shown that effective recovery and concentration of Uranium(VI) are combined with a high rate of Uranium(VI) sorption. Quantitative characteristics of Uranium sorption under dynamic conditions such as dynamic exchange capacity, total dynamic exchange capacity, degree of Uranium recovery, Uranium content in the phase of the sorbent, sorption rate were calculated. It was established that the fibrous polyampholyte FIBAN АC-22V demonstrated the better indicators of Uranium(VI) sorption from sulfate solutions and concentration of these solutions (5.2 – 10.5 times) than other fibrous ion exchangers. It was shown that a 10-fold increase in the Uranium concentration in solutions leads to a considerable improvement of the sorption quantitative characteristics. It was found that the initial form of the fibrous ion exchangers can be completely restored by passing through the ion exchangers in Uranium form of a 0.5 M HCl or H2SO4 solutions. It was established that the fibrous polyampholyte FIBAN АC-22V advantageously be used for one cycle of Uranium(VI) sorption – desorption, and the fibrous cation exchanger FIBAN C-1 can be used during two cycles of Uranium(VI) sorption – desorption. The interaction mechanism of the Uranium(VI) compounds present in sulfate solutions (uranyl cations, neutral and negative sulfate complexes) with functional groups of studied sorbents was proposed.Встановлено, що волокнисті іоніти ФІБАН є ефективними сорбційними матеріалами для вилучення сполук урану (VI) з сульфатних розчинів в динамічному режимі при високій швидкості (25 см3/хв) пропускання розчину крізь іоніти. Показано, що обробка іонітів, насичених сполуками урану, 0,5 М розчинами HCl або H2SO4 призводить до концентрування урановмісних розчинів у 2,0 – 10,5 разів та до регенерації сорбентів більш ніж на 95%. Встановлено, що для вилучення та концентрування сполук урану з сульфатних розчинів волокнистий поліамфоліт ФІБАН АК-22В доцільно використовувати протягом одного циклу сорбція – десорбція, а волокнистий катіоніт ФІБАН К-1 – протягом двох циклів. Запропоновано механізм взаємодії сполук урану, присутніх в сульфатних розчинах, з функціональними групами волокнистих іонітів ФІБАН

LANTANIUM COMPOUNDS FLOTOEXTRACTION ISOLATION FROM DILUTE AQUEOUS SOLUTIONS

The high efficiency of the flotoextraction method for the lanthanum compounds removal from dilute aqueous solutions using the thin-emulsified higher carboxylic acids has been established. It is shown that the thin-emulsified decanoic and dodecanoic acids are the best collectors of the lanthanum compounds. The lantanium compounds can be removal using these acids by 90-97 % with a minimum flow of the collector consumption and high speed of the process. With the thin-emulsified heptanoic, octanoic and nonanoic acids the lanthanum compounds can be removaled by 85-93 % under the optimal conditions of the process

URANIUM(VI) FLOTOEXTRACTION ISOLATION FROM DILUTE AQUEOUS SOLUTIONS WITH ELECTROLYTE ADDITIONS PRESENCE

Purposefulness of the uranium(VI) flotoextraction isolation from their diluted nitrate, sulphate and carbonate solutions in the presence of electrolyte additions using the thin-emulsified solution of the trialkylamine in white spirit has been found. It has been shown that in the presence of electrolyte additions uranium compound isolation degree decreased by 10—15%, optimal pH range got narrow and displaced to neutral medium, the collector optimal consumption decreased considerably, rate constants increased into 1,5—2 times. High efficiency of the uranium(VI) flotoextraction isolation has been showed by tests carried out on carbonate and sulfate model solutions

Несуча здатність, жорсткість та деформативність залізобетоелементів, підсилених наклеюванням зовнішнього армування нних

The materials of the article are devoted to the development of a method for calculating the bearing capacity, strength, stiffness and deformability of reinforced concrete bending elements reinforced by gluing external reinforcement, based on real diagrams of deformation of concrete and reinforcement.Материалы статьи посвящены разработке методики расчета несущей способности, прочности, жесткости и деформативности железобетонных изгибаемых элементов, усиленных путем наклеивания внешнего армирования, на основе реальных диаграмм деформирования бетона и арматуры.Матеріали статті присвячені розробці методики розрахунку несучої здатності, міцності, жорсткості та деформативності залізобетонних елементів, що згинаються, посилених шляхом наклеювання зовнішнього армування, на основі реальних діаграм деформування бетону та арматури

COOLOIDAL-CHEMICAL PROPERTIES OF THE SUSPENSIONS OF DIFFERENT RADICAL PHOSPHINE OXIDE IN PARAFFIN SOLID SOLUTIONS

The influence of the composition of the solid and liquid phases to some colloid-chemical properties (wetting angle, dynamic viscosity, dispersion, specific surface) of the suspensions of different radical phosphine oxide (DRPO) solid solutions in paraffin. The concentration of the solid solution of DRPO in paraffin, optimum for using this reagent as a carrier during flotation extracting of rare metals compounds were determined

THIN EMULSIFIED SOLUTIONS OF TRIALKYLAMINE IN KEROSENE AS COLLECTORS FOR FLOTATION–EXTRACTION OF THORIUM (VI) COMPOUNDS

The principle possibility of using the thin emulsified solutions of trialkylamine in kerosene as collector of thorium compounds for their flotation extraction has been established. The colloid- chemical properties of the collector water emulsions were defined. The average radius of the emulsion droplets is equal to 1.36·10-7 m, and their electrokinetic potential is equal to +38 mV. The optimal conditions of thorium compounds flotation-extraction process have been determined. These are temperature 293 K, the initial thorium concentration 20 mg/dm3, collector consumption 2 mol TAA/mol Th, flotation time 15 min. The degree of thorium removal is 98%, the degree of emulsions dispersed phase removal is 96% under optimal conditions for floatation-extraction. The kinetics of flotation-extraction is described by the first-order equation. The rate constants and apparent activation energy of flotation-extraction process have been calculated in the temperature range 29-323 K. The rate constants are equal to (3.0-10.5)∙10-4 s-1 and apparent activation energy is equal to 33 kJ/mol. Тhe interaction mechanism for of thorium compounds with the collector at different pH has been proposed. According to this mechanism the thorium compounds such as [ThSO4]2+, [Th( SO4)2]0, [Th(OH)3] +, Th(OH)4, interact with the amino groups of trialkylamine and naphthenic acids of kerosene both on the surface and in the volume of the collector emulsions droplets

ТОНКОЕМУЛЬГОВАНІ РОЗЧИНИ ТРИАЛКІЛАМІНУ В ГАСІ ЯК ЗБИРАЧІ ДЛЯ ФЛОТОЕКСТРАКЦІЙНОГО ВИЛУЧЕННЯ СПОЛУК ТОРІЮ (IV)

The principle possibility of using the thin emulsified solutions of trialkylamine in kerosene as collector of thorium compounds for their flotation extraction has been established. The colloid- chemical properties of the collector water emulsions were defined. The average radius of the emulsion droplets is equal to 1.36·10-7 m, and their electrokinetic potential is equal to +38 mV. The optimal conditions of thorium compounds flotation-extraction process have been determined. These are temperature 293 K, the initial thorium concentration 20 mg/dm3, collector consumption 2 mol TAA/mol Th, flotation time 15 min. The degree of thorium removal is 98%, the degree of emulsions dispersed phase removal is 96% under optimal conditions for floatation-extraction. The kinetics of flotation-extraction is described by the first-order equation. The rate constants and apparent activation energy of flotation-extraction process have been calculated in the temperature range 29-323 K. The rate constants are equal to (3.0-10.5)∙10-4 s-1 and apparent activation energy is equal to 33 kJ/mol. Тhe interaction mechanism for of thorium compounds with the collector at different pH has been proposed. According to this mechanism the thorium compounds such as [ThSO4]2+, [Th( SO4)2]0, [Th(OH)3] +, Th(OH)4, interact with the amino groups of trialkylamine and naphthenic acids of kerosene both on the surface and in the volume of the collector emulsions droplets.Встановлено, що сполуки торію можуть бути ефективно (на 98%) вилучені з розбавлених водних розчинів методом флотоектракції за допомогою тонкоемульгованих розчинів триалкіламіну в гасі. Визначено колоїдно-хімічні властивості емульсій збирача та оптимальні умови здійснення флотоекстракції. Запропоновано механізм взаємодії сполук торію зі збирачем при різних рН, розраховано константи швидкості флотоекстракції та уявна енергія активації

Identification and analysis of the chivosazol biosynthetic gene cluster from the myxobacterial model strain Sorangium cellulosum So ce56

Perlova O, Gerth K, Kaiser O, Hans A, Muller R. Identification and analysis of the chivosazol biosynthetic gene cluster from the myxobacterial model strain Sorangium cellulosum So ce56. JOURNAL OF BIOTECHNOLOGY. 2006;121(2):174-191.Myxobacteria belonging to the genus Sorangium are known to produce a variety of biologically active secondary metabolites. Chivosazol is a macrocyclic antibiotic active against yeast, filamentous fungi and especially against mammalian cells. The compound specifically destroys the actin skeleton of eucaryotic cells and does not show activity against bacteria. Chivosazol contains an oxazole ring and a glycosidically bound 6-deoxyglucose (except for chivosazol F). In this paper we describe the biosynthetic gene cluster that directs chivosazol biosynthesis in the model strain Sorangium cellulosum So ce56. This biosynthetic gene cluster spans 92 kbp on the chromosome and contains four polyketide synthase genes and one hybrid polyketide synthase/nonribosomal peptide synthetase gene. An additional gene encoding a protein with similarity to different methyltransferases and presumably involved in post-polyketide modification was identified downstream of the core biosynthetic gene cluster. The chivosazol biosynthetic gene locus belongs to the recently identified and rapidly growing class of trans-acyltransferase polyketide synthases, which do not contain acyltransferase domains integrated into the multimodular megasynthetases. (c) 2005 Elsevier B.V. All rights reserved