Cyclometallated platinum(II) complexes containing NHC ligands: synthesis, characterization, photophysics and their application as emitters in OLEDs.

A series of square planar [Pt(N^C)(NHC)L] complexes containing cyclometallated N^C ligands (phenylpyridine and benzoquinoline) and N-heterocyclic carbene (NHC)--N^C = 2-phenylpyridine, 7,8-benzoquinoline; NHC = 1,3-dibenzylbenzimidazolium, 1,3-diethylbenzimidazolium, 1,3-dibenzylimidazolium; L = Cl, Br, -C2Ph--have been synthesized in moderate to good yields. The complexes obtained were characterized using chemical analysis, MS-ESI spectrometry, NMR spectroscopy and X-ray crystallography. The complexes display moderate to strong phosphorescence in solution (Q.

Investigation of unusual growth and phenotypic characteristics of plasmid-containing and plasmid-free strains of oligotrophic bacterium Ancylobacter vacuolatus.

The oligotrophic bacterium Ancylobacter vacuolatus contains two large plasmids pREV1 and pREV2 (about 150 and 250 kb, respectively). Plasmid pREV1 carries the genes responsible for resistance to chloramphenicol, trimethoprim and y-irradiation. Plasmid pREV2 carries the genes responsible for resistance to beta-lactam antibiotics and formation of gas vacuoles.

A new adenovirus based vaccine vector expressing an Eimeria tenella derived TLR agonist improves cellular immune responses to an antigenic target.

Background: Adenoviral based vectors remain promising vaccine platforms for use against numerous pathogens, including HIV. Recent vaccine trials utilizing Adenovirus based vaccines expressing HIV antigens confirmed induction of cellular immune responses, but these responses failed to prevent HIV infections in vaccinees. This illustrates the need to develop vaccine formulations capable of generating more potent T-cell responses to HIV antigens, such as HIV-Gag, since robust immune responses to this antigen correlate with improved outcomes in long-term non-progressor HIV infected individuals.

Protein from intestinal Eimeria protozoan stimulates IL-12 release from dendritic cells, exhibits antitumor properties in vivo and is correlated with low intestinal tumorigenicity.

The small intestine (SI) of vertebrates exhibits low tumorigenesis and rarely supports metastatic growth from distant tumors. Many theories have been proposed to address this phenomenon, but none has been consistently supported. One candidate mechanism is that the vast immunologic compartment of the SI provides a heightened level of tumor immunosurveillance.

[Some aspects of antibiotic resistance of oligotrophic bacteria].

Antibiotic resistance spectra of a large group of oligotrophic and eutrophic bacteria from the open soil and aquatic ecosystems were studied. It was shown that sometimes antibiotic resistance of the oligotrophs was of plasmid nature. A possible transfer of plasmid antibiotic resistance from oligotrophs to pathogenic eutrophic soil and aquatic bacteria in the natural ecosystems is discussed.

[Free iron in bacteria].

Free iron content has been estimated in autotrophic and heterotrophic bacteria. It constituted 40-50 micrograms/g dry weight as compared to 15 micrograms/g dry weight in animal cells. A method for estimation of free iron has been proposed.

Evolutionary relationship of some stalked and budding bacteria (genera Caulobacter, "Hyphobacter", Hyphomonas and Hyphomicrobium) as studied by the new integral taxonomical method.

A new approach was developed for the determination of taxonomic and evolutional relationships among four genera of oligotrophic bacteria. The main idea of this approach is the algorithmized integrative analysis of the morphological and physiological specificity of these bacteria, their 5S rRNA sequences, fatty acid and lipid composition of their membranes, as well as their sensitivity to a large variety of antibiotics. It was shown that the genera Caulobacter and Hyphomonas are closely related to each other, but they are both distant from Hyphomicrobium species.

[Clustering of oligotrophic microorganisms on the basis of their antibiotic resistance and dynamic membrane characteristics].

Some oligotrophic microorganisms were characterised in terms of their resistance against a broad spectrum of antibiotics and certain dynamic parameters of membranes obtained by analysing the EPR and NMR spectra. The oligotrophic bacteria differed in these characteristics from eutrophic microorganisms. The oligotrophic bacteria were subdivided into 3-4 subgroups different in many of the studied parameters.

Drug-dependent mutants in yeast Saccharomyces cerevisiae.

Mutations in sup1 and sup2 genes may cause cycloheximide-dependent growth in yeast Saccharomyces cerevisiae. Two classes of such mutants are described in the paper: 1) high temperature sensitive mutants, which do not express their sensitivity to nonpermissive temperature in the presence of cycloheximide (conditionally dependent) and 2) mutants unable to grow in the absence of the drug (true dependent). Some of the mutants of both classes express dependence toward another antibiotic - trichodermine.

Ribosomal protein S1 associates with Escherichia coli ribosomal 30-S subunit by means of protein-protein interactions.

Ribosomal proteins S1 when associated with the 30-S subunit does not interact with 16-S RNA but its binding is determined mostly by protein-protein interactions. These conclusions are based on the following data. 1.