Observation of conformational changes that underlie the catalytic cycle of Xrn2

Nuclear magnetic resonance (NMR) methods that quantitatively probe motions on molecular and atomic levels have propelled the understanding of biomolecular processes for which static structures cannot provide a satisfactory description. In this work, we studied the structure and dynamics of the essential 100-kDa eukaryotic 5′→3′ exoribonuclease Xrn2. A combination of complementary fluorine and methyl-TROSY NMR spectroscopy reveals that the apo enzyme is highly dynamic around the catalytic center. These observed dynamics are in agreement with a transition of the enzyme from the ground state into a catalytically competent state. We show that the conformational equilibrium in Xrn2 shifts substantially toward the active state in the presence of substrate and magnesium. Finally, our data reveal that the dynamics in Xrn2 correlate with the RNA degradation rate, as a mutation that attenuates motions also affects catalytic activity. In that light, our results stress the importance of studies that go beyond static structural information

Электроснабжение установки перекачки нефти п. Пионерный ОАО «Томскнефть»

РЕФЕРАТ Выпускная квалификационная работа 149 с., 23 рис., 32 табл., 29 источников, 6 прил. Ключевые слова: нефтепровод, насос, электрооборудование, схема электроснабжения, линия, сеть, электроприемник, нагрузка, оборудование, защита, ток, напряжение, мощность. Объектом исследования является электрическая часть УПН п. Пионерный ОАО «Томскенефть». Цель работы – проектирование схемы электроснабжения предприятия, выбор оборудования. В процессе исследования проводился сбор исходных данных в ходе производственной практики на объекте исследования. В результате была спроектирована схема электроснабжения от подстанции энергосистемы, до конечного электроприемника. Были выбраны кабели и провода, коммутационное оборудование, были сделаны необходимые проверки. Также результатом работы сталESSAY Final qualifying work 149 p., 23 fig., 32 tab., 29 sources, 6 adj. Keywords: oil, pump, electrical equipment, power supply circuit, line, network, power-consuming equipment, load equipment, protection, current, voltage, power. The object of research is the electrical part of UPN claim. Pionerny of "Tomskeneft". The purpose of work - designing enterprise power scheme, the choice of equipment. The study was conducted to collect baseline data in the course of practical training on the subject of the study. As a result, power supply circuit has been designed from the substation grid, appliance, to the end. Were selected cables and wires, switching equipment, the necessary checks have been made. It is also the result of the work became an economic calculation of capital costs for the con

Thermal effects influencing stability and performance of coatings in automotive applications

International audienc

Comparison of midregional pro-atrial natriuretic peptide with N-terminal pro-B-type natriuretic peptide in the diagnosis of heart failure

The concentration of atrial natriuretic peptide (ANP) in the circulation is approximately 10- to 50- fold higher than B-type natriuretic peptide (BNP). We sought to compare the accuracy of midregional pro-atrial natriuretic peptide (MRproANP) measured with a novel sandwich immunoassay with N-terminal pro-B-type natriuretic peptide (NTproBNP) in the diagnosis of heart failure.; The diagnosis of heart failure was adjudicated by two independent cardiologists using all available clinical data (including BNP levels) in 287 consecutive patients presenting with dyspnoea to the emergency department (ED). MRproANP and NTproBNP levels were determined at presentation in a blinded fashion.; Heart failure was the adjudicated final diagnosis in 154 patients (54%). Median MRproANP was significantly higher in patients with heart failure as compared to patients with other causes of dyspnoea (400 vs. 92 pmol L(-1), P > 0.001). The diagnostic accuracy of MRproANP was very high with an area under the receiver operating characteristic curve of 0.92 and was comparable with that of NTproBNP (0.92, P = 0.791). Moreover, MRproANP provided incremental diagnostic information to BNP and NTproBNP in patients presenting with BNP levels in the grey zone between 100 and 500 pg mL(-1).; Midregional pro-atrial natriuretic peptide is as accurate in the diagnosis of heart failure as NTproBNP. MRproANP seems to provide incremental information on top of BNP or NT-proBNP in some subgroups and should be further investigated in other studies