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Krasnov K.A.,Federal Medical Biological Agency | Kartsev V.G.,InterBioScreen Ltd. | Khrustalev V.N.,RAS Nesmeyanov Institute of Organoelement Compounds
Tetrahedron | Year: 2010

Knoevenagel products formed by the condensation of N-monoalkyl barbituric acids with o-tert-amino benzaldehydes undergo tert-amino effect reactions (T-reactions) yielding 1-alkyl-2,4,6-trioxoperhydropyrimidine-5-spiro-3′- (1′,2′,3′,4′-tetrahydroquinoline) derivatives as a mixture of (S*,S*)- and (S*,R*)-diastereomers. Mostly, the major diastereomer has the S*,S*-configuration. According to X-ray diffraction data in the solid form and NOE data in solution, diastereoselectivity of the T-reactions can be associated with the structure of the Knoevenagel products whose conformation is fixed by the strong intramolecular C-H⋯π interaction. © 2010 Elsevier Ltd. All rights reserved. Source


Safonova T.N.,RAS A.N. Bach Institute of Biochemistry | Mikhailov S.N.,RAS Engelhardt Institute of Molecular Biology | Veiko V.P.,RAS A.N. Bach Institute of Biochemistry | Mordkovich N.N.,RAS A.N. Bach Institute of Biochemistry | And 5 more authors.
Acta Crystallographica Section D: Biological Crystallography | Year: 2014

Uridine phosphorylase (UP; EC 2.4.2.3), a key enzyme in the pyrimidine-salvage pathway, catalyzes the reversible phosphorolysis of uridine to uracil and ribose 1-phosphate. Expression of UP from Shewanella oneidensis MR-1 (SoUP) was performed in Escherichia coli. The high-resolution X-ray structure of SoUP was solved in the free form and in complex with uridine. A crystal of SoUP in the free form was grown under microgravity and diffracted to ultrahigh resolution. Both forms of SoUP contained sulfate instead of phosphate in the active site owing to the presence of ammonium sulfate in the crystallization solution. The latter can be considered as a good mimic of phosphate. In the complex, uridine adopts a high-syn conformation with a nearly planar ribose ring and is present only in one subunit of the hexamer. A comparison of the structures of SoUP in the free form and in complex with the natural substrate uridine showed that the subunits of the hexamer are not identical, with the active sites having either an open or a closed conformation. In the monomers with the closed conformation, the active sites in which uridine is absent contain a glycerol molecule mimicking the ribose moiety of uridine. © 2014 International Union of Crystallography. Source


Pinegin B.,Federal Medical Biological Agency | Vorobjeva N.,Moscow State University | Pinegin V.,Moscow State University
Autoimmunity Reviews | Year: 2015

The pathogenesis of many autoimmune diseases is initially based on a redundant or prolonged activation of the innate immune system. It was suggested that an excessive activation of the innate immunity is often the result of a chronic inflammatory process in the organism. This inflammation can be induced by exogenous and endogenous alarm factors, or alarmins. We believe that the recently discovered neutrophil extracellular traps, or NETs, completely meet the criteria of alarmins. This review summarizes current knowledge concerning the general characteristics of NETs, their antimicrobial properties, and their role in the development of chronic inflammatory processes that underlie the pathogenesis of psoriasis and atherosclerosis. Studies on the NETosis can provide the foundation for developing new diagnostic methods and effective treatment of chronic inflammatory and autoimmune diseases. © 2015 Elsevier B.V. Source


Safonova T.N.,RAS A.N. Bach Institute of Biochemistry | Mordkovich N.N.,RAS A.N. Bach Institute of Biochemistry | Polyakov K.M.,RAS Engelhardt Institute of Molecular Biology | Manuvera V.A.,Federal Medical Biological Agency | And 2 more authors.
Acta Crystallographica Section F: Structural Biology and Crystallization Communications | Year: 2012

Uridine phosphorylase (UDP, EC 2.4.2.3), a key enzyme in the pyrimidine salvage pathway, catalyses the reversible phosphorolysis of uridine to uracil and ribose 1-phosphate. The gene expression of UDP from Shewanella oneidensis MR-1 was performed in the recipient strain Escherichia coli. The UDP protein was crystallized on earth (in the free form and in complex with uridine as the substrate) by the hanging-drop vapour-diffusion method at 296 K and under microgravity conditions (in the free form) aboard the Russian Segment of the International Space Station by the capillary counter-diffusion method. The data sets were collected to a resolution of 1.9 Å from crystals of the free form grown on earth, 1.6 Å from crystals of the complex with uridine and 0.95 Å from crystals of the free form grown under microgravity. All crystals belong to the space group P21 and have similar unit-cell parameters. The crystal of uridine phosphorylase grown under microgravity diffracted to ultra-high resolution and gave high-quality X-ray diffraction data. © 2012 International Union of Crystallography All rights reserved. Source


Vorobjeva N.V.,Moscow State University | Pinegin B.V.,Federal Medical Biological Agency
Biochemistry (Moscow) | Year: 2014

Recent insights into the specific type of cell death characteristic of neutrophils, called NETosis, are summarized. NETosis is a process of generation of Neutrophil Extracellular Traps (NETs), whose main components are DNA, granular antimicrobial peptides, and nuclear and cytoplasmic proteins. The structure of NETs determines their bactericidal, fungicidal, antiprotozoal, and antiviral properties. Therefore, NETs production by neutrophils is an essential immune response to infection. In addition to the antimicrobial function, NETosis is involved in many inflammatory and autoimmune disorders and participates in the regulation of noninfectious processes. The molecular mechanisms of NET formation, bactericidal effect, and involvement in some noninfectious, autoimmune, and inflammatory processes are discussed in detail in this review. © 2014 Pleiades Publishing, Ltd. Source

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