139 research outputs found
ВЗАЄМОДІЯ СТРАТЕГІЧНОГО ТА ОПЕРАЦІЙНОГО УПРАВЛІННЯ ПРОЕКТНО-ОРІЄНТОВАНОЮ ОРГАНІЗАЦІЄЮ
Project-oriented organizations peculiarities appear in changes in governance level structure. The fact that in such organizations initial hierarchic governance levels derive from direct internal company control and pass to each team specific project control has been shown. It makes difficult to control achieving organisation’s goals. Accordingly, with the aim of defining project success deflated indicators contribution (positive or negative) in achieving strategic project goals, their monitoring actualization has been set forward.Особливості управління проектно-орієнтованою організацією (ПОО) проявляються у зміні структури рівнів управління. Показано, що нижні ієрархічні рівні управління в таких організаціях виводяться з безпосереднього внутрішньо фірмового підпорядкування та переходять до підпорядкування команди кожного конкретного проекту. Це ускладнює контроль за досягненням стратегічних цілей організації. Тому запропоновано здійснювати моніторинг обчислювальних показників успішності проекту, з метою визначення їх внеску (позитивного або негативного) у досягнення стратегічних цілей проекту
NMR assignments of the N-terminal domain of Ogataea polymorpha telomerase reverse transcriptase
© 2015, Springer Science+Business Media Dordrecht.Telomerase is a ribonucleoprotein enzyme that adds telomeric DNA fragments to the ends of chromosomes. This enzyme is the focus of substantial attention, both because its structure and mechanism of action are still poorly studied, and because of its pivotal roles in aging and cellular proliferation. The use of telomerase as a potential target for the design of new anticancer drugs is also of great interest. The catalytic protein subunit of telomerase (TERT) contains an N-terminal domain (TEN) that is essential for activity and processivity. Elucidation of the structure and dynamics of TEN in solution is important for understanding the molecular mechanism of telomerase activity and for the design of new telomerase inhibitors. To approach this problem, in this study we report the 1H, 13C, and 15N chemical shift assignments of TEN from Ogataea polymorpha. Analysis of the assigned chemical shifts allowed us to identify secondary structures and protein regions potentially involved in interaction with other participants of the telomerase catalytic cycle
NMR screening of potential inhibitors of methionine γ-lyase from Citrobacter freundii
© 2014, Pleiades Publishing, Inc. Methionine γ-lyase [EC 4.4.1.11] participates in methionine catabolism in a number of bacteria and protozoa eukaryotes, including pathogenic microorganisms. The lack of this enzyme in mammals allows us consider it to be a promising target for rational antibacterial drug design. Currently, in medical practice, there are no preparations based on the inhibition of methionine γ-lyase. We present the results of a search for potential inhibitors of this enzyme using NMR screening techniques based on the identification of compounds, which are able to bind specifically to their biological target. The study included a stage of in silico virtual screening of the library of commercially available compounds and subsequent experimental selection of the leading compounds capable to interact with the enzyme. The identification of binding was carried out using saturation transfer difference (STD) spectroscopy and the WaterLOGSY technique. During the final stage, an experimental assessment of the inhibition activity of the selected compounds in the reaction of the γ elimination of L-methionine catalyzed by methionine γ-lyase was performed. Binding constants of two leading compounds were determined using the WaterLOGSY method. This study expands the structural group of potential inhibitors of methionine γ-lyase and allows us to approach the design of its inhibitors with higher efficacy
NMR assignments of the N-terminal domain of Ogataea polymorpha telomerase reverse transcriptase
© 2015 Springer Science+Business Media Dordrecht Telomerase is a ribonucleoprotein enzyme that adds telomeric DNA fragments to the ends of chromosomes. This enzyme is the focus of substantial attention, both because its structure and mechanism of action are still poorly studied, and because of its pivotal roles in aging and cellular proliferation. The use of telomerase as a potential target for the design of new anticancer drugs is also of great interest. The catalytic protein subunit of telomerase (TERT) contains an N-terminal domain (TEN) that is essential for activity and processivity. Elucidation of the structure and dynamics of TEN in solution is important for understanding the molecular mechanism of telomerase activity and for the design of new telomerase inhibitors. To approach this problem, in this study we report the 1H, 13C, and 15N chemical shift assignments of TEN from Ogataea polymorpha. Analysis of the assigned chemical shifts allowed us to identify secondary structures and protein regions potentially involved in interaction with other participants of the telomerase catalytic cycle
Control of Azomethine Cycloaddition Stereochemistry by CF<inf>3</inf> Group: Structural Diversity of Fluorinated β-Proline Dimers
© 2016 American Chemical Society.β-Proline-functionalized dimers consisting of homochiral monomeric units were synthesized by a non-peptidic coupling method for the first time. The applied synthetic methodology is based on 1,3-dipolar cycloaddition chemistry of azomethine ylides and provides absolute control over the β-proline backbone stereogenic centers. An o-(trifluoromethyl)phenyl substituent contributes to appropriate stabilization of the definite acrylamide chiral cis conformation and to achieve the dipole reactivity that is not observed for aryl groups lacking strong electronegative character
Chemical shift assignments and the secondary structure of the Est3 telomerase subunit in the yeast Hansenula polymorpha
© 2017 Springer Science+Business Media B.V. Telomerase is a multisubunit ribonucleoprotein enzyme that is essential for continuous cellular proliferation. A key role of telomerase in cancer and ageing makes it a promising target for the development of cancer therapies and treatments of other age-associated diseases, since telomerase allows unlimited proliferation potential of cells in the majority of cancer types. However, the structure and molecular mechanism of telomerase action are still poorly understood. In budding yeast, telomerase consists of the catalytic subunit, the telomerase reverse transcriptase or Est2 protein, telomerase RNA (TLC1) and two regulatory subunits, Est1 and Est3. Each of the four subunits is essential for in vivo telomerase function. Est3 interacts directly with Est1 and Est2, and stimulates Est2 catalytic activity. However, the exact role of the Est3 protein in telomerase function is still unknown. Determination of the structure, dynamic and functional properties of Est3 can bring new insights into the molecular mechanism of telomerase activity. Here we report nearly complete 1 H, 13 C and 15 N resonance assignments of Est3 from the yeast Hansenula polymorpha. Analysis of the assigned chemical shifts allowed us to identify the protein’s secondary structure and backbone dynamic properties. Structure-based sequence alignment revealed similarities in the structural organization of yeast Est3 and mammalian TPP1 proteins
Theoretical and NMR Conformational Studies of β-Proline Oligopeptides With Alternating Chirality of Pyrrolidine Units
NMR Structures of Apo L. casei Dihydrofolate Reductase and Its Complexes with Trimethoprim and NADPH: Contributions to Positive Cooperative Binding from Ligand-Induced Refolding, Conformational Changes, and Interligand Hydrophobic Interactions
bS Supporting Information The enzyme dihydrofolate reductase (DHFR; 5,6,7,8-tetra-hydrofolate:NADPH oxidoreductase, EC 1.5.1.3) catalyzes the reduction of 7,8-dihydrofolate (DHF) to 5,6,7,8-tetrahydro-folate (THF) using NADPH as coenzyme.1 Since THF and its metabolites are precursors of purine and pyrimidine bases, the normal functioning of this enzyme is essential for proliferating cells. This makes DHFR an excellent target for antifolate drugs such as methotrexate (anticancer), pyrimethamine (antimalarial), and trimethoprim (antibacterial). Such agents act by inhibiting the enzyme in parasitic or malignant cells.1,2 The cooperative binding of ligands to DHFR plays an important role not only in the enzyme catalytic cycle (negative cooperativity in THF/ NADPH binding)3 but also in enzyme inhibition (positive cooperativity in antifolate/NADPH binding).4 The effects of positive cooperative binding in controlling enzyme inhibition ar
NMR assignments of the WBSCR27 protein related to Williams-Beuren syndrome
© 2018, Springer Science+Business Media B.V., part of Springer Nature. Williams-Beuren syndrome is a genetic disorder characterized by physiological and mental abnormalities, and is caused by hemizygous deletion of several genes in chromosome 7. One of the removed genes encodes the WBSCR27 protein. Bioinformatic analysis of the sequence of WBSCR27 indicates that it belongs to the family of SAM-dependent methyltransferases. However, exact cellular functions of this protein or phenotypic consequences of its deficiency are still unknown. Here we report nearly complete 1H, 15N, and 13C chemical shifts assignments of the 26 kDa WBSCR27 protein from Mus musculus in complex with the cofactor S-adenosyl-l-methionine (SAM). Analysis of the assigned chemical shifts allowed us to characterize the protein’s secondary structure and backbone dynamics. The topology of the protein’s fold confirms the assumption that the WBSCR27 protein belongs to the family of class I methyltransferases
Structure and function of the N-terminal domain of the yeast telomerase reverse transcriptase
© The Author(s) 2017. The elongation of single-stranded DNA repeats at the 3'-ends of chromosomes by telomerase is a key process in maintaining genome integrity in eukaryotes. Abnormal activation of telomerase leads to uncontrolled cell division, whereas its down-regulation is attributed to ageing and several pathologies related to early cell death. Telomerase function is based on the dynamic interactions of its catalytic subunit (TERT) with nucleic acids-telomerase RNA, telomeric DNA and the DNA/RNA heteroduplex. Here, we present the crystallographic and NMR structures of the N-terminal (TEN) domain of TERT from the thermotolerant yeastHansenula polymorpha and demonstrate the structural conservation of the core motif in evolutionarily divergent organisms. We identify the TEN residues that are involved in interactions with the telomerase RNA and in the recognition of the 'fork' at the distal end of the DNA product/RNA template heteroduplex. We propose that the TEN domain assists telomerase biological function and is involved in restricting the size of the heteroduplex during telomere repeat synthesis
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