Effect of Non-Thermal Plasma on Proliferative Activity and Adhesion of Multipotent Stromal Cells to Scaffolds Developed for Tissue-Engineered Constructs.

We studied the effect of non-thermal argon plasma on proliferative activity of bone marrow multipotent stromal cells in vitro. Treatment of stromal cell suspension with pure argon did not affect their proliferation. The cells treated with non-thermal argon plasma and explanted in the treatment medium demonstrated growth inhibition by 30-40% in comparison with the control. Multipotent stromal cells treated with plasma and after centrifugation explanted in normal medium within 12 min demonstrated accelerated growth. The total cell growth from the pellet and supernatant significantly exceeded the control values. We also analyzed adhesion and proliferative activity of multipotent stromal cells treated with non-thermal plasma on bioresorbable carriers. The cells adhered and proliferated on all types of studied samples. Adhesion properties of scaffolds differed. Caprolactone was found to be the most suitable material for adhesion and proliferation of multipotent stromal cells.

Terahertz-infrared spectroscopy of Shewanella oneidensis MR-1 extracellular matrix.

Employing optical spectroscopy we have performed a comparative study of the dielectric response of extracellular matrix and filaments of electrogenic bacteria Shewanella oneidensis MR-1, cytochrome c, and bovine serum albumin. Combining infrared transmission measurements on thin layers with data of the terahertz spectra, we obtain the dielectric permittivity and AC conductivity spectra of the materials in a broad frequency band from a few cm-1 up to 7000 cm-1 in the temperature range from 5 to 300 K. Strong absorption bands are observed in the three materials that cover the range from 10 to 300 cm-1 and mainly determine the terahertz absorption. When cooled down to liquid helium temperatures, the bands in Shewanella oneidensis MR-1 and cytochrome c reveal a distinct fine structure. In all three materials, we identify the presence of liquid bound water in the form of librational and translational absorption bands at ≈ 200 and ≈ 600 cm-1, respectively. The sharp excitations seen above 1000 cm-1 are assigned to intramolecular vibrations.

Creation of a producent, optimization of expression, and purification of recombinant Yersinia pseudotuberculosis L-asparaginase.

Recombinant E. coli strain producing Y. pseudotuberculosis Q66CJ2 (YpA) L-asparaginase II was created. Gene ansB homologue encoding Y. pseudotuberculosis IP 32953 L-asparaginase precursor was synthesized. The gene was cloned in pBad24 expression vector and expressed in E. coli BL21 (DE3) strain. Optimal conditions for the producer strain culturing were selected. An effective method for isolation and purification of the enzyme by two-staged column chromatography was developed.

Draft De Novo Genome Assembly of Acinetobacter pittii Strain VKPM B-3780, a Prospective Multifunctional Bioremediation Agent.

Acinetobacter pittii strain VKPM B-3780 is a prospective degrader of oil and methanol, isolated from industrial wastewater. Here, we present the draft genome sequence of strain VKPM B-3780, obtained using Illumina sequencing of the fragment genomic library.

Draft Genome Sequence of Rhodococcus erythropolis VKPM Ac-1659, a Putative Oil-Degrading Strain Isolated from Polluted Soil in Siberia.

The draft genome sequence of Rhodococcus erythropolis VKPM Ac-1659, a putative oil-degrading strain, is reported. This genome sequence may provide better insights into the diversity and evolution of the genes responsible for hydrocarbon degradation in soil microorganisms.

Tissue Engineered Neural Constructs Composed of Neural Precursor Cells, Recombinant Spidroin and PRP for Neural Tissue Regeneration.

We have designed a novel two-component matrix (SPRPix) for the encapsulation of directly reprogrammed human neural precursor cells (drNPC). The matrix is comprised of 1) a solid anisotropic complex scaffold prepared by electrospinning a mixture of recombinant analogues of the spider dragline silk proteins - spidroin 1 (rS1/9) and spidroin 2 (rS2/12) - and polycaprolactone (PCL) (rSS-PCL), and 2) a "liquid matrix" based on platelet-rich plasma (PRP). The combination of PRP and spidroin promoted drNPC proliferation with the formation of neural tissue organoids and dramatically activated neurogenesis. Differentiation of drNPCs generated large numbers of ßIII-tubulin and MAP2 positive neurons as well as some GFAP-positive astrocytes, which likely had a neuronal supporting function. Interestingly the SPRPix microfibrils appeared to provide strong guidance cues as the differentiating neurons oriented their processes parallel to them. Implantation of the SPRPix matrix containing human drNPC into the brain and spinal cord of two healthy Rhesus macaque monkeys showed good biocompatibility: no astroglial and microglial reaction was present around the implanted construct. Importantly, the human drNPCs survived for the 3 month study period and differentiated into MAP2 positive neurons. Tissue engineered constructs based on SPRPix exhibits important attributes that warrant further examination in spinal cord injury treatment.

[Experimental models of transgenic plants promising for the modern technologies].

Transgenic popato plants have been created which express recombinant proteins, analogues of spidroin 1, the protein of the cobweb skeleton thread. Expression of the hybrid spidroin 1 genes possessing some repeated sequences retains both in the model test-tube-growing plants and in the crops. Expression level of the synthetic spidroin 1 genes and the level of accumulation of their products in plants depend on the type of promoter, number of repeats, organ specificity and plant species but not on the duration of plant material storage. The results show that the strategy based on constuction and expression of hybrid proteins which include the reporter protein makes it easier to select and analyse expression of hybrid proteins in transgenic organisms.

Observation of dielectric universalities in albumin, cytochrome C and Shewanella oneidensis MR-1 extracellular matrix.

The electrodynamics of metals is well understood within the Drude conductivity model; properties of insulators and semiconductors are governed by a gap in the electronic states. But there is a great variety of disordered materials that do not fall in these categories and still respond to external field in an amazingly uniform manner. At radiofrequencies delocalized charges yield a frequency-independent conductivity σ 1(ν) whose magnitude exponentially decreases while cooling. With increasing frequency, dispersionless conductivity starts to reveal a power-law dependence σ 1(ν)∝ν s with s < 1 caused by hopping charge carriers. At low temperatures, such Universal Dielectric Response can cross over to another universal regime with nearly constant loss ε″∝σ1/ν = const. The powerful research potential based on such universalities is widely used in condensed matter physics. Here we study the broad-band (1-1012 Hz) dielectric response of Shewanella oneidensis MR-1 extracellular matrix, cytochrome C and serum albumin. Applying concepts of condensed matter physics, we identify transport mechanisms and a number of energy, time, frequency, spatial and temperature scales in these biological objects, which can provide us with deeper insight into the protein dynamics.

[Construction of the synthetic genes for protein analogs of spider silk carcass spidroin 1 and their expression in tobacco plants]. / Konstruirovanie sinteticheskikh genov, kodiruiushchikh belki-analogi belka karkasnoi niti pautiny spidroina 1, i ikh ékspressiia v rasteniiakh tabaka.

To obtain transgenic tobacco plants expressing recombinant analogs of spider dragline silk spidroin 1, artificial 1f5 and 1f9 coding for spidroin 1 analogs were 3'-fused in-frame with the reporter lichenase gene. The Tr2' weak constitutive promoter of Agrobacterium tumefaciens T-DNA and the strong constitutive promoter of the cauliflower mosaic virus 35S RNA gene were used as regulatory elements. The expression cassettes were used to transform agrobacteria and then introduced in tobacco leaf disks. On evidence of Southern hybridization, transgenic plants each carried a single copy of a hybrid gene, which corresponded in size to the constructed one. Zymography and Western blotting revealed full-length hybrid proteins in leaf extracts of transgenic plants. The results testified that plants can maintain and express synthetic genes for spider silks and, consequently, may be used as a convenient producer of recombinant silk analogs.

[On the involvement of the regulatory gene prqR in the development of resistance to methyl viologen in cyanobacterium Synechocystis sp. PCC6803]. / Ob uchastii reguliartornogo gena prqR v razvitii ustoichivosti k metilviologenu u tsianobakterii Synechocystis sp. PCC6803.

The role of the prqR gene in the regulation of the adaptive response of the cyanobacterium Synechocystis sp. PCC6803 to the oxidative stress induced with methyl viologen (MV) was studied. For this, transcription activity of prqR and the genes, which may be involved in the control of resistance to MV, was determined by means of Northern blot hybridization in wild-type cells and in the MV-resistant Prq20 mutant with a mutation located in the DNA-binding domain of the PrqR protein. It was ascertained that the prqR gene is a component of the prqR-prqA operon and down regulates its transcription. In cells of the wild-type strain containing MV, the autorepressor activity of the PrqR protein enhances and transcription of mvrA and sodB genes encoding an respectively assumed transporter protein and iron-containing superoxide dismutase increases. The prqR gene may be involved in the negative, indirect control of transcription of these genes. The Prq20 mutant is characterized by an MV-independent derepression of the prqR-prqA operon and by a slightly increased transcription of mvrA and sodB genes not stimulated by MV. Nevertheless, the expression of mvrA and sodB genes was lower than in wild-type cells after the MV treatment. On the strength of this evidence, it is assumed that the main mechanism underlying for the resistance to MV in the Prq20 mutant is derepression of the prqA gene, the product of which is homologous to multidrug transporters, drug efflux proteins.

[Antitumor activity of L-asparaginase from Yersinia pseudotuberculosis].

The cytotoxic activity of L-asparaginases from Yersinia pseudotuberculosis and from Erwinia carotovora were investigated in vitro using several tumor cells lines: Jurkat and Molt-4 (human T-lymphoblastic leukemia), MCF-7 (human breast adenocarcinoma), LnCap (human prostate carcinoma), NGUK1 (rat Gasser node neurinoma). E. coli L-asparaginase produced by "Medak" (Germany) was used as a reference. The cell growth inhibition data indicate that Y. pseudotuberculosis L-asparaginase significantly inhibits growth of leukemic and solid tumor cells. These results allow us to conclude that this L-asparaginase can be used for the development of new preparations for the therapy of different types of tumors.

[Study of the functional role of Ctp-family proteins in Synechocystis sp. PCC 6803 cyanobacteria]. / Izuchenie funktsional'noi roli belkov Ctp-semeistva u tsianobakterii Synechocystis sp. PCC 6803.

To understand the functional role of CtpB and CtpC proteins, which are similar to the C-terminal processing CtpA peptidase, the effect of the insertional inactivation of the ctpB and ctpC genes on the phenotypic characteristics of Synechocystis sp. PCC 6803 was studied. The inactivation of the ctpC gene was found to be lethal to the cyanobacterium, which indicates a vital role of the CtpC protein. The mutant with the inactivated ctpB gene had the same photosynthetic characteristics as the wild-type strain. The double mutant@[delta]ctpA delta ctpB with the two deleted genes was identical, in the phenotypic characteristics, to the mutant with a knock-out mutation in the ctpA gene, which was unable to grow photoautotrophically. The data obtained suggest that, in spite of the high similarity of the Ctp proteins, they serve different functions in Synechocystis sp. PCC 6803 cells and cannot compensate for each other.