Time filter

Source Type

Fomich M.A.,National Academy of Sciences of Belarus | Kvach M.V.,National Academy of Sciences of Belarus | Navakouski M.J.,Primetech ALC | Weise C.,Free University of Berlin | And 3 more authors.
Organic Letters

Azide and phosphoramidite functions were found to be compatible within one molecule and stable for months in solution kept frozen at -20 °C. An azide-carrying phosphoramidite was used for direct introduction of multiple azide modifications into synthetic oligonucleotides. A series of azide-containing oligonucleotides were modified further using click reactions with alkynes. © 2014 American Chemical Society. Source

Ponomarenko A.I.,RAS Shemyakin Ovchinnikov Institute of Bioorganic Chemistry | Brylev V.A.,RAS Shemyakin Ovchinnikov Institute of Bioorganic Chemistry | Nozhevnikova E.V.,RAS Shemyakin Ovchinnikov Institute of Bioorganic Chemistry | Korshun V.A.,RAS Gause Institute of New Antibiotics
Current Topics in Medicinal Chemistry

The combined efforts of chemistry, nanotechnology, and spectroscopy led to the development of self-assembled fluorescent DNA nanostructures, an inexhaustible source of refined and bizarre tools and powerful techniques for research and diagnostic applications. This multidisciplinary area has tremendous prospects for science and technology. © 2015 Bentham Science Publishers. Source

Cogoi S.,University of Udine | Zorzet S.,University of Trieste | Shchekotikhin A.E.,RAS Gause Institute of New Antibiotics | Xodo L.E.,University of Udine
Journal of Medicinal Chemistry

We previously found that two neighboring G-quadruplexes behave as a molecular switch controlling the expression of HRAS (Cogoi, S.; Schekotikhin, A. E.; Xodo, L. E. Nucl. Acids Res. 2014, DOI: 10.1093/nar/gku574). In this study we have designed anthrathiophenediones with two chloroacetamidine-containing side chains (CATDs) as G-quadruplex binders and have examined their anticancer activity in T24 bladder cancer cells bearing mutant HRAS and in T24 xenografts. The designed CATDs (3a-e), bearing alkyl side chains of different length, penetrate T24 cancer cells more than their analogues with guanidine-containing side chains. The lead compounds 3a and 3c inhibit HRAS expression, metabolic activity, and colony formation in T24 cancer cells. They also activate a strong apoptotic response, as indicated by PARP-1, caspases 3/7, and annexin V/propidium iodide assays. Apoptosis occurs under conditions where cyclin D1 is down-regulated and the cell cycle arrested in G2 phase. Finally, compound 3a inhibits the growth of T24 xenografts and increases the median survival time of nude mice. © 2015 American Chemical Society. Source

Grum-Grzhimaylo A.A.,Wageningen University | Georgieva M.L.,RAS Gause Institute of New Antibiotics | Bondarenko S.A.,Moscow State University | Debets A.J.M.,Wageningen University | Bilanenko E.N.,Moscow State University
Fungal Diversity

The diversity of filamentous fungi that can grow at high ambient pH values (i.e., 8–11) remains largely understudied. Here we study 100 alkalitolerant and alkaliphilic isolates from the soils around the basin of soda lakes in Asia and Africa to assess the major evolutionary lineages and morphologies pertinent to the alkaliphilic trait in filamentous fungi. The Emericellopsis lineage (Hypocreales, Hypocreomycetidae), along with Plectosphaerellaceae (Hypocreomycetidae), Pleosporaceae (Dothideomycetes), Chaetomiaceae (Sordariomycetidae) families appeared to be overrepresented with strong alkalitolerants and effective alkaliphiles. In particular, Sodiomyces species (Plectosphaerellaceae), Acrostalagmus luteoalbus (Plectosphaerellaceae), Emericellopsis alkalina (Hypocreales), Thielavia sp. (Chaetomiaceae), and Alternaria sect. Soda (Pleosporaceae) grew best at high ambient pH. The pH tolerance of Chordomyces antarcticum, Acrostalagmus luteoalbus and some other species was largely affected by the presence of extra Na+ in the growth medium. Moderate alkalitolerants included Scopulariopsis members (Microascales), Fusarium, Cladosporium, and many asexual acremonium-like species from Bionectriaceae. Weak alkalitolerants were represented by sporadic isolates of Penicillium, Purpureocillium lilacinum, and Alternaria alternata species, with the growth optimum at neutral or acidic pH. Weak alkalitolerants develop loose dry chains of spores easily dispersed by air. Their presence at low frequency with the growth optimum at neutral or acidic pH leads us to treat them as transient species in the alkaline soils, as those are also ubiquitous saprobes in normal soils. Our phylogenetic analyses show that the alkaliphilic trait in filamentous fungi has evolved several times. Several lineages harboring strong alkalitolerants derived from the known marine-borne fungi (Emericellopsis, Alternaria sect. Phragmosporae), or fall within the fungi associated with halophytic grasses (Pleosporaceae). Soda soils contain a diversity of fungi that range from weak alkalitolerant to alkaliphilic, which in few cases is associated with darkly pigmented mycelium and formation of microsclerotia. The alkaliphilic trait is spread throughout the Ascomycota, and usually juxtaposes with slime-covered polyphyletic acremonium-, verticillium-, gliocladium-types of asexual morphology, hyphae aggregating in chords, and enclosed fruit bodies. © 2015, The Author(s). Source

Tevyashova A.N.,RAS Gause Institute of New Antibiotics | Olsufyeva E.N.,RAS Gause Institute of New Antibiotics
Russian Chemical Reviews

The review is devoted to the latest achievements in the design of dual action antibiotics-heterodimeric (chimeric) structures based on antibacterial agents of different classes (fluoroquinolones, anthracyclines, oxazolidines, macrolides and so on). Covalent binding can make the pharmacokinetic characteristics of these molecules more predictable and improve the penetration of each component into the cell. Consequently, not only does the drug efficacy increase owing to inhibition of two targets but also the resistance to one or both antibiotics can be overcome. The theoretical grounds of elaboration, design principles and methods for the synthesis of dual action antibiotics are considered. The structures are classified according to the type of covalent spacer (cleavable or not) connecting the moieties of two agents. Dual action antibiotics with a spacer that can be cleaved in a living cell are considered as dual action prodrugs. Data on the biological action of heterodimeric compounds are presented and structure ± activity relationships are analyzed. The bibliography includes 225 references. © 2015 Russian Academy of Sciences and Turpion Ltd Source

Discover hidden collaborations