Role of phosphate-coordinating arginine residues in the thermal stability of uridine phosphorylase from Shewanella oneidensis MR-1.

The role of phosphate-coordinating arginine residues in the thermal stability of uridine phosphorylase from Shewanella oneidensis MR-1 was investigated by mutation analysis. Uridine phosphorylase mutant genes were constructed by site-directed mutagenesis. The enzyme mutants were prepared and isolated, and their kinetic parameters were determined.

Vanadate as a new substrate for nucleoside phosphorylases.

Orthovanadate was shown to serve as a substrate for nucleoside phosphorylases from Escherichia coli, Shewanella oneidensis, Geobacillus stearothermophilus, and Halomonas chromatireducens AGD 8-3. An exception is thymidine phosphorylase from the extremophilic haloalkaliphilic bacterium Halomonas chromatireducens AGD 8-3, which cannot catalyze the vanadolysis of nucleosides. The kinetic parameters of nucleoside vanadolysis were evaluated.

Extracellular DNA Containing (dG)n Motifs Penetrates into MCF7 Breast Cancer Cells, Induces the Adaptive Response, and Can Be Expressed.

Background: Oxidized human DNA or plasmid DNAs containing human ribosomal genes can easily penetrate into the breast cancer cells MCF7 and stimulate the adaptive response induction. Plasmid DNA containing a CMV promoter, gene , and the insertion of the human ribosomal genes can be expressed. A hypothesis is proposed: these features of the ribosomal DNA are due to the presence of dGn motifs that are prone to oxidize.

Ribosomal DNA as DAMPs Signal for MCF7 Cancer Cells.

The cell free ribosomal DNA (cf-rDNA) is accrued in the total pool of cell free DNA (cfDNA) in some non-cancer diseases and demonstrates DAMPs characteristics. The major research questions: (1) How does cell free rDNA content change in breast cancer; (2) What type of response in the MCF7 breast cancer cells is caused by cf-rDNA; and (3) What type of DNA sensors (TLR9 or AIM2) is stimulated in MCF7 in response to the action of cf-rDNA? CfDNA and gDNA were isolated from the blood plasma and the cells derived from 38 breast cancer patients and 20 healthy female controls. The rDNA content in DNA was determined using non-radioactive quantitative hybridization.

Increased Transfection of the Easily Oxidizable GC-Rich DNA Fragments into the MCF7 Breast Cancer Cell.

Objective: Easily oxidizable GC-rich DNA (GC-DNA) fragments accumulate in the cell-free DNA (cfDNA) of patients with various diseases. The human oxidized DNA penetrates the MCF7 breast cancer cells and significantly changes their physiology. It can be assumed that readily oxidizable GC-DNA fragments can penetrate the cancer cells and be expressed.

Concerted action of two subunits of the functional dimer of Shewanella oneidensis MR-1 uridine phosphorylase derived from a comparison of the C212S mutant and the wild-type enzyme.

Uridine phosphorylase (UP; EC 2.4.2.

[Structural and Functional Organization of the Signal Peptide of ProEnterotoxin B from Staphylococcus aureus].

A series of genes of proenterotoxin B from Staphylococcus aureus containing signal peptide mutant forms was constructed in order to study the functional roles of the introduced mutations. It was shown that a continuous mutation in the n-region of the signal peptide does not affect the secretion efficiency of proenterotoxin B, in contrast to the analogous mutation in the h-region. Point mutations of the proprotein signal peptide, including the N-terminal amino-acid residue of the mature protein, were obtained.

[Investigation of Protein Translocation Sec-System with Heterologous Gene Expression in Shewanella oneidensis MR-1 Bacterium Cells].

A comparison of the primary structures of the protein translocation Sec-system proteins in the Shewanella oneidensis MR-1 and Escherichia coli bacteria was carried out. The process of translocation of recombinant pro-enteroxins (SEB and SEH) from Staphylococcus aureus and pro-streptavidin (SAV) from Streptomyces avidinii in the S. oneidensis MR-1 and E.

New limit on the T-violating transverse muon polarization in K+-->pi0mu+nu decays.

A search for T-violating transverse muon polarization (P(T)) in the K+-->pi(0)mu(+)nu decay was performed using kaon decays at rest. A new improved value P(T)=-0.0017+/-0.

[Design of the human tumor-associated VNTR(Muc1) antigen gene, fused with streptavidin, its expression in Escherichia coli. Study of properties of the hybrid protein].

A gene of human tumor-associated antigen VNTR(MUC1) bound to streptavidin, an expression plasmid, and a highly effective hybrid protein-producing strain were constructed. It was shown that the streptavidin leader peptide ensures an effective secretion of the hybrid protein into the periplasmic space of Escherichia coli cells. The hybrid protein was isolated in a homogeneous state and its immunogenic properties were studied.

[Cloning of streptavidin gene from Streptomyces avidinii and its expression in Escherichia coli. Secretion of streptavidin by E. coli cells].

The streptavidin gene from Streptomyces avidinii was cloned, an expression plasmid constructed, and a highly effective strain producer of streptavidin created. It was shown that the leader peptide of streptavidin ensures the effective secretion of this protein into the periplasmic space of Escherichia coli cells. The degradation site of the leader peptide was detected.