Primary cell wall inspired micro containers as a step towards a synthetic plant cell.

The structural integrity of living plant cells heavily relies on the plant cell wall containing a nanofibrous cellulose skeleton. Hence, if synthetic plant cells consist of such a cell wall, they would allow for manipulation into more complex synthetic plant structures. Herein, we have overcome the fundamental difficulties associated with assembling lipid vesicles with cellulosic nanofibers (CNFs). We prepare plantosomes with an outer shell of CNF and pectin, and beneath this, a thin layer of lipids (oleic acid and phospholipids) that surrounds a water core. By exploiting the phase behavior of the lipids, regulated by pH and Mg2+ ions, we form vesicle-crowded interiors that change the outer dimension of the plantosomes, mimicking the expansion in real plant cells during, e.g., growth. The internal pressure enables growth of lipid tubules through the plantosome cell wall, which paves the way to the development of hierarchical plant structures and advanced synthetic plant cell mimics.

Bioinspired capsules based on nanocellulose, xyloglucan and pectin - The influence of capsule wall composition on permeability properties.

Materials based on renewable biopolymers, selective permeability and stimuli-responsive release/loading properties play an important role in biomedical applications. Here, in order to mimic the plant primary cell-wall, microcapsules have been fabricated using cell wall polysaccharides, namely pectin, xyloglucan and cellulose nanofibers. For the first time, a large amount of xyloglucan was successfully included in such capsules. These capsules demonstrated stimuli-responsive (ON/OFF) permeability and biocompatibility. The live cell staining revealed that the microcapsules' surface enhanced cell growth and also the non-toxic nature of the microcapsules. In water, the microcapsules were completely and partially permeable to fluorescent dextrans with an average molecular weight of 70 kDa (hydrodynamic diameter of ca. 12 nm) and 2000 kDa (ca. 54 nm), respectively. On the other hand, the permeability dropped quickly when the capsules were exposed to 250 mM NaCl solution, trapping a fraction of the 70 kDa dextrans in the capsule interior. The decrease in permeability was a direct consequence of the capsule-wall composition, i.e. the presence of xyloglucan and a low amount of charged molecules such as pectin. The low permeability of capsules in saline conditions (and in a model biological medium), combined with a capsule wall that is made from dietary fibers only, potentially enables their use in biological applications, such as colon targeted delivery in the gastro-intestinal tract. STATEMENT OF SIGNIFICANCE: For the first time, microcapsules have been prepared that possess capsule walls that mimic the primary cell wall found in natural plant cells. The capsules were assembled using pectin, xyloglucan and cellulose in the form of cellulose nanofibers. The capsules demonstrated stimuli-responsive (ON/OFF) permeability and biocompatibility. The low permeability of capsules in saline conditions (and in a model biological medium), combined with a capsule wall that is made from dietary fibers only, potentially enables their use in biological applications, such as colon targeted delivery in the gastro-intestinal tract. Such model plant cell capsules might also further improve the understanding for the digestion and release of nutrients from natural plant cells found in vegetables and fruits.

Gas-assisted electron-beam-induced nanopatterning of high-quality titanium oxide.

Electron-beam-induced deposition of titanium oxide nanopatterns is described. The precursor is titanium tetra-isopropoxide, delivered to the deposition point through a needle and mixed with oxygen at the same point via a flow through a separate needle. The depositions are free of residual carbon and have an EDX determined stoichiometry of TiO2.2. High resolution transmission electron microscopy and Raman spectroscopy studies reveal an amorphous structure of the fabricated titanium oxide. Ellipsometric characterization of the deposited material reveals a refractive index of 2.2-2.4 RIU in the spectral range of 500-1700 nm and a very low extinction coefficient (lower than 10(-6) in the range of 400-1700 nm), which is consistent with high quality titanium oxide. The electrical resistivity of the titanium oxide patterned with this new process is in the range of 10-40 GΩ cm and the measured breakdown field is in the range of 10-70 V µm(-1). The fabricated nanopatterns are important for a variety of applications, including field-effect transistors, memory devices, MEMS, waveguide structures, bio- and chemical sensors.

[The comparative evaluation of effectiveness of laboratory techniques of diagnostic of anthrax and detection its agent in objects of environment].

The analysis of samples received during ictus of anthrax in the Stavropolskii kraii in 2013 permitted to study comparative effectiveness of regulated methods of laboratory diagnostic. The effectiveness of bacteriological, biological and molecular methods and necessity of their complex application for receiving optimal results are confirmed. The rapidity, effectiveness and specificity of polymerase chain reaction is emphasized. This method in case of absence of isolation of anthrax microbe can be the only method of confirming diagnose in people in aggregate with typical clinical picture and corresponding epidemic situation.

[Use of GIS technologies in development of a cadaster of stationary unfavorable by anthrax points in Krasnodar region].

AIM: Development of a cadaster of stationary unfavorable by anthrax points in Krasnodar region by using GIS technologies. MATERIALS AND METHODS: Ageographical information system (GIS) of ESRI program--Arc GIS 10.1 was used for the composition of an electronic cadaster of stationary unfavorable by anthrax points. Topographic basis--electronic maps of Krasnodar region (M 1:200 000). RESULTS: An evaluation of safety by anthrax of Krasnodar region areas bythe amount of stationary unfavorable by anthrax points situated in its territories, by their activity during the 76 year observation period was given. Spatial adjoint analysis of ecological timing of stationary unfavorable by anthrax points to soil and landscape zones in Krasnodar region was carried out. CONCLUSION: Electronic cadaster of stationary unfavorable by anthrax points in Krasnodar region may serve as a basis for purposeful implementation of prophylaxis measures.

Gas-assisted electron-beam-induced nanopatterning of high-quality Si-based insulator.

An oxygen-assisted electron-beam-induced deposition (EBID) process, in which an oxygen flow and the vapor phase of the precursor, tetraethyl orthosilicate (TEOS), are both mixed and delivered through a single needle, is described. The optical properties of the SiO(2+δ) (- 0.04 ≤ δ ≤ +0.28) are comparable to fused silica. The electrical resistivity of both single-needle and double-needle SiO(2+δ) are comparable (greater than 7 GΩ cm) and a measured breakdown field is greater than 400 V µm(-1). Compared to the double-needle process the advantage of the single-needle technique is the ease of alignment and the proximity to the deposition location, which facilitates fabrication of complex 3D structures for nanophotonics, photovoltaics, micro- and nano-electronics applications.

[Oligomerization of site-specific nicking endonuclease BspD6I at high protein concentrations].

Ability of site-specific nickase BspD6I (Nt.BspD6I) to oligomerize at concentrations > or = 0.5 microM (> or = 0.035 mg/mL) is studied. Three states of Nt.BspD6I are registered via electrophoretic studies both in the presence and in the absence of DNA. Estimation of their molecular mass allows assigning them as a monomer, a dimer and a trimer. Both dimeric and monomeric Nt.BspD6I are shown to hydrolyze its DNA substrate with the identical specificity. Calculation of the electrostatic potential distribution on the Nt.BspD6I globule surface shows that the protein molecule is a dipole. The Nt. BspD6I oligomeric forms are likely to be the result of ionic protein interactions.

[Analysis of outbreak of anthrax in Omsk region in 2010].

AIM: Carrying out analysis of epizootologic-epidemiologic situation on anthrax that had emerged in Omsk region in 2010 when horse meat from epizootic focus of anthrax was used in production of meat semi-finished products. MATERIALS AND METHODS: Study of samples for detection of anthrax causative agents and strain identification was performed according to guidelines 1.3.2569-09. Strain genotyping was performed by MLVA method. RESULTS: The epizootologic-epidemiologic investigation performed allowed to detect the causes of emergence of anthrax outbreak, its routes and factors of transmission. MLVA genotyping results gave evidence on the single origin of Bacillus anthracis strains isolated from sick animals, humans and food substances. CONCLUSION: Timely execution of a complex of epizootic and epidemic control measures allowed to localize epizootic and epidemic focus of anthrax as well as prevent a possible large scale development of epidemic complications.

[About non-specific prophylaxis of infections typical for organized groups].

Respiratory tract infections and pyodermia are typical for personnel doing military service under conscription. Risk of progression of these infections is connected with activation of carry-over of causative agents among military personnel during replacement and decrease in immunity of conscripts. Usage of medication "Karmolis Kapli" for the purpose of prophylaxis allows to reduce cases of respiratory tract infections among the military personnel. Among the military servicemen who had take "Karmolis Kapli" was noted reduction of community-acquired pneumonia, tonsillitis and pyodermia morbidity. Non-specific protective effect of medication "Karmolis Kapli" is conditioned by increase of the common resistance of the body. For the purpose of prophylaxis it is necessary to use this medication during the personnel formation before the beginning of seasonal morbidity.

Rapid electron beam assisted patterning of pure cobalt at elevated temperatures via seeded growth.

A new method of direct, rapid nano- to micro-scale patterning of high purity cobalt is presented. The method utilizes a combination of electron beam induced deposition (EBID) and seeded growth at elevated temperatures below the temperature of spontaneous thermal decomposition. Dicobalt octacarbonyl Co2(CO)8 is used as the precursor and carbon as a seed layer. Seeded deposition is carried out in the substrate temperature range from 55 to 75 °C. Deposition yield is significantly higher than conventional EBID and magnetotransport measurements indicate that resistivity, 22 µΩ cm, and saturation magnetization, 1.55 T, are much closer to the corresponding values for bulk Co than those for standard EBID.

Electron beam induced deposition at elevated temperatures: compositional changes and purity improvement.

Thermally assisted electron beam induced deposition can result in an improvement of the purity of nano-scale depositions. Six commonly used organic precursors were examined: W(CO)(6), TEOS (tetraethylorthosilicate), MeCpPtMe(3), Co(CO)(3)NO, Co(2)(CO)(8), and Me(2)Auacac. The last two precursors were also tested on two different instruments to confirm reproducibility of the results. The influence of the substrate temperature on the composition of the deposition has been quantified systematically in the temperature range 25-360 °C. It has been shown that most purities improve when applying an elevated temperature, while the shape of the deposition remains intact. The purity improvement is achieved at the cost of a lower deposition yield. The amount of improvement is different for each precursor. Within the maximum temperature range of 360 °C, the best improvement was found for W(CO)(6): from 36.7 at.% at 25 °C to 59.2 at.% at 280 °C. For both cobalt precursors an additional transition region between patterned electron beam induced deposition (EBID) and thermal thin film growth has been identified. In this region seeded growth occurs with strongly increased growth rates.

[Secondary structure of SsoII-like (cytosine-5)-DNA methyltransferases N-terminal region determined by circular dichroism spectroscopy].

(Cytosine-5)-DNA methyltransferase SsoII (M.SsoII) has a long N-terminal region (1-71 residues) preceding the sequence with conservative motifs, which are characteristic for all DNA methyltransferases of such kind. The presence of this region provides M.SsoII capability to act as a transcription regulator in SsoII restriction-modification system. To perform its regulatory function, M.SsoII binds specifically to a 15-mer inverted repeat in the promoter region of SsoII restriction-modification system genes. In the present work, properties of the protein delta(72-379)M.Ecl18kI are studied, which is a deletion mutant of the SsoII-like DNA-methyltransferase M.Ecl18kI and is homologous to M.SsoII N-terminal region. delta(72-379)M.Ecl18kI capability to bind specifically a DNA duplex containing the regulatory site is demonstrated. However, such a binding takes place only in the presence of high protein excess relative to DNA, which could indicate an altered structure in the deletion mutant in comparison with the full-length M.SsoII. Circular dichroism spectroscopy demonstrated that delta(72-379)M.Ecl18kI has a strongly pronounced secondary structure and contains 32% a-helices and 20% beta-sheets. Amino acid sequences alignment of M.SsoII N-terminal region and transcription factors of known spatial structure is made. An assumption is made how alpha-helices and beta-sheets are arranged in M.SsoII N-terminal region.

[New derivatives of azobenzene for the directed modification of proteins].

Derivatives of azobenzene which contained a maleimide group in one of the benzene rings (for binding to a protein cysteine residue) and maleimide, hydroxyl, or carboxyl substitutes in another benzene ring were synthesized. The reactivity of these compounds towards a cysteine residue of a protein and their optical properties in a free state and after their attachment to the mutant forms of the SsoII restriction endonuclease were studied.

[Methodic approaches to testing Bacillus anthracis susceptibility to antibacterials].

Susceptibility of 50 isolates of Bacillus anthracis to 24 antibiotics was tested by the disk-diffusion method and the method of serial dilutions in solid media. The tests allowed to determine the boundary values of the growth inhibition zones and the minimum inhibitory concentrations of the antibiotics for susceptible and resistant strains of B. anthracis. Nutrient media and reference strains for testing antibiotic susceptibility of B. anthracis are recommended.

[Improvement of methods for identification of atypical anthrax strains and their differentiation from closely related bacilli].

AIM: To study biologic characteristics of atypical strains of anthrax agent in order to improve methods of identification and differentiation from closely related bacilli. MATERIALS AND METHODS: Objects of the study were 1101 strains of microorganisms of which following were experimentally examined: atypical--40 strains, typical--2, saprophytic bacilli from Bacillus genus--50. Aside from conventional methods, additional tests for intraspecies differentiation as well as multiplex PCR method were used for identification. RESULTS: Isolation rate of atypical strains of anthrax agent in natural conditions as well as frequency of misidentification of bacillary strains as Bacillus anthracis was assessed. Phenotypical test for determination of susceptibility to penicillin was improved. Variant of multiplex PCR for differentiation of B. anthracis strains with any set of plasmids from closely related bacilli strains was developed. Feasibility to use multiple loci analysis of 6 chromosomal and 2 plasmid regions of B. anthracis genome containing variable number of tandem repeats (MLVA) for differentiation of B. anthracis strains from other bacilli from Bacillus genus was demonstrated. CONCLUSION: In order to optimize the processes of identification of B. anthracis typical and atypical strains and differentiation between closely related bacilli, it is rational to use disk-diffusion method with commercially available disks of penicillin, multiprimer PCR and MLVA on 6 chromosomal and 2 plasmid loci.

[Phenotypic and genetic features of cultural-morphologic variants of Bacillus anthracis].

Comparative analysis of MVLA-genotypes of 6 Bacillus anthracis strains and 40 their variants differing on capsule- and toxin synthesis, hemolytic, proteolytic and lecitinase activity, nutritional requirements, susceptibility to anthrax bacteriophages, virulence, immunogenicity, and presence of genes for capsule and toxin synthesis was performed. Results of phylogenetic analysis of 5 chromosome locuses and plasmid locus pXO1aat which are variable for this sample of B. anthracis cultures showed that all strains divided on 2 main clusters - A and B. Cluster A consisted of 5 genotypes whereas cluster B - of 1 genotype. All highly virulent original strains and variants with characteristic phenotype Cap(CO2)(+)(O2)(-)Tox(+)ProtA(+)Hly(+) Lec(-)Trp(+) had identical genotype in 4 groups and in 5th group differences were present only in vrrA locus. All original strains and variants with the most atypical complex of phenotypic characteristics Cap (CO2)(+)(O2)(+)Tox(-)ProtA(-)Hly(-)Lec(-)Trp(-) also had the same genotype belonging to cluster B and diverged on characteristic of 5 chromosomal VNTR locuses and pXO1aat locus from typical strains. Absence of toxin production in vitro was not related to loss of genetic determinants of toxin components. Cultures with typical characteristics, one of which was ability to produce toxin in vitro, had larger sizes of amplicons of pXO1aat locus (135 and 132 nbp), whereas atoxigenic original strains and variants with complex of atypical characteristics and identical chromosome genotype had the smallest sizes (123 bnp). All original cultures were isolated in Russia, their genotypes are described for the first time.

[Germination of Bacillus anthracis spores].

The influence of amino acids, nucleosides and inorganic components on the kinetics and effectiveness of the germination of B. anthracis spores was studied. The study revealed that the rapid germination of the spores took place after their activation at 65 degrees C in tris buffer with L-alanine in combination with inosine or adenosine added; less pronounced germinative action was caused by the addition of alanine only and the combination of phenylalanine, tyrosine and tryptophan. The rapidity of germination and the sets of effective germinants for spores of different strains were different. All B. anthracis strains under study had nucleotide sequences, of gene gerX in their genome.

[Multiplex amplification test system for the identification and differentiation of Bacillus anthracis].

The multiplex amplification test system for the identification of Bacillus anthracis with primers to plasmid cya (pX01), capC (pX02) genes and chromosomal sap gene were developed. The primers to sap gene were selected by the authors and, after being tested on 72 microbial strains of the genus Bacillus, proposed as more specific in comparison with the known primers to chromosomal locus Ba 813. The proposed test system permitted the simultaneous identification of B. anthracis of all plasmid variants, the evaluation of their potential virulence and the differentiation of B. anthracis nonplasmid strains from bacilli of the group Bacillus cereus.

[Characterization of Bacillus anthracis typical virulent test strain 81/1].

The results of the prolonged and many-sided study of B. anthracis strain 81/1 by different authors are presented. The cultural and morphological, biochemical, antigenic, molecular-genetic characteristics of this strain give grounds for regarding it as a typical test strain to be used for the determination of the vaccines immunogenicity, the effectiveness of antibiotics and immunomodulators.