Methionine gamma lyase fused with S3 domain VGF forms octamers and adheres to tumor cells via binding to EGFR.

Methods for targeting enzymes exhibiting anticancer properties, such as methionine γ-lyase (MGL), have not yet been sufficiently developed. Here, we present the data describing the physico-chemical properties and cytotoxic effect of fusion protein MGL-S3 - MGL from Clostridium sporogenes translationally fused to S3 domain of the viral growth factor of smallpox. MGL-S3 has methioninase activity comparable to native MGL. In solution, MGL-S3 protein primarily forms octamers, whereas native MGL, on the contrary, usually forms tetramers. MGL-S3 binds to the surface of the neuroblastoma SH-SY5Y and epidermoid carcinoma A431 cells and, unlike native MGL, remains there and retains its cytotoxic effect after media removal. In HEK293T cells lacking EGFRs, no adhesion was recorded. Confocal fluorescence microscopy confirms the preferential adhesion of MGL-S3 to tumor cells, while it avoids getting into lysosomes. Both MGL and MGL-S3 arrest cell cycle of SH-SY5Y cells mainly in the G1 phase, while only MGL-S3 retains this ability after washing the cells.

Ferritin-based fusion protein shows octameric deadlock state of self-assembly.

Ferritin is a universal protein complex responsible for iron perception in almost all living organisms and has applications from fundamental biophysics to drug delivery and structure-based immunogen design. Different platforms based on ferritin share similar technological challenges limiting their development - control of self-assembling processes of ferritin itself as well as ferritin-based chimeric recombinant protein complexes. In our research, we studied self-assembly processes of ferritin-based protein complexes under different expression conditions. We fused a ferritin subunit with a SMT3 protein tag, a homolog of human Small Ubiquitin-like Modifier (SUMO-tag), which was taken to destabilize ferritin 3-fold channel contacts and increase ferritin-SUMO subunits solubility. We first obtained the octameric protein complex of ferritin-SUMO (8xFer-SUMO) and studied its structural organization by small-angle X-ray scattering (SAXS). Obtained SAXS data correspond well with the high-resolution models predicted by AlphaFold and CORAL software of an octameric assembly around the 4-fold channel of ferritin without formation of 3-fold channels. Interestingly, three copies of 8xFer-SUMO do not assemble into 24-meric globules. Thus, we first obtained and structurally characterized ferritin-based self-assembling oligomers in a deadlock state. Deadlock oligomeric states of ferritin extend the known scheme of its self-assembly process, being new potential tools for a number of applications. Finally, our results might open new directions for various biotechnological platforms utilizing ferritin-based tools.

Photorhabdus lux-operon heat shock-like regulation.

For decades, transcription of Photorhabdus luminescens lux-operon was considered being constitutive. Therefore, this lux-operon has been used for measurements in non-specific bacterial luminescent biosensors. Here, the expression of Photorhabdus lux-operon under high temperature was studied. The expression was researched in the natural strain Photorhabdus temperata and in the heterologous system of Escherichia coli. P. temperata FV2201 bacterium was isolated from soil in the Moscow region (growth optimum 28 °C). We showed that its luminescence significantly increases when the temperature rises to 34 °C. The increase in luminescence is associated with an increase in the transcription of luxCDABE genes, which was confirmed by RT-PCR. The promoter of the lux-operon of the related bacterium P. luminescens ZM1 from the forests of Moldova, being cloned in the heterologous system of E. coli, is activated when the temperature rises from room temperature to 42 °C. When heat shock is caused by ethanol addition, transcription of lux-operon increases only in the natural strain of P. temperata, but not in the heterologous system of E. coli cells. In addition, the activation of the lux-operon of P. luminescens persists in E. coli strains deficient in both the rpoH and rpoE genes. These results indicate the presence of sigma 32 and sigma 24 independent heat-shock-like mechanism of regulation of the lux-operon of P. luminescens in the heterologous E. coli system.

Correction: Genotoxic effect of 2,2'-bis(bicyclo[2.2.1] heptane) on bacterial cells.

[This corrects the article DOI: 10.1371/journal.pone.0228525.].

Genotoxic effect of 2,2'-bis(bicyclo[2.2.1] heptane) on bacterial cells.

The toxic effect of strained hydrocarbon 2,2'-bis (bicyclo[2.2.1]heptane) (BBH) was studied using whole-cell bacterial lux-biosensors based on Escherichia coli cells in which luciferase genes are transcriptionally fused with stress-inducible promoters. It was shown that BBH has the genotoxic effect causing bacterial SOS response however no alkylating effect has been revealed. In addition to DNA damage, there is an oxidative effect causing the response of OxyR/S and SoxR/S regulons. The most sensitive to BBH lux-biosensor was E. coli pSoxS-lux which reacts to the appearance of superoxide anion radicals in the cell. It is assumed that the oxidation of BBH leads to the generation of reactive oxygen species, which provide the main contribution to the genotoxicity of this substance.

Methionine Gamma Lyase from Clostridium sporogenes Increases the Anticancer Efficacy of Doxorubicin on A549 Cancer Cells In Vitro and Human Cancer Xenografts.

The anticancer efficacy of methionine γ-lyase (MGL) from Clostridium sporogenes (C. sporogenes) is described. MGL was active against cancer cells in vitro and in vivo. Doxorubicin (DOX) and MGL were more effective on A549 human lung-cancer growth inhibition than either agent alone in vitro and in vivo.

Methionine gamma lyase from Clostridium sporogenes increases the anticancer effect of doxorubicin in A549 cells and human cancer xenografts.

The anti-cancer efficacy of methionine γ-lyase (MGL) from Clostridium sporogenes (C. sporogenes) is described. MGL was active against cancer models in vitro and in vivo. The calculated EC50 values for MGL were 4.4 U/ml for A549, 7.5 U/ml for SK-BR3, 2.4 U/ml for SKOV3, and 0.4 U/ml for MCF7 cells. The combination of doxorubicin (DOX) and MGL was more effective for A549 human lung cancer growth inhibition than either agent alone in vitro and in vivo. MGL reduced the EC50 of doxorubicin from 35.9 µg/mL to 0.01-0.265 µg/mL. The growth inhibitory effect of DOX + MGL on A549 xenografts in vivo was reflective of the results obtained in vitro. The inhibition rate of tumor growth in the combined arm was 57%, significantly higher than that in the doxorubicin (p = 0.033)-alone arm.

Experimental study of the diagnostic potentialities of bioimpedance measurement in acute intestinal obstruction.

The dynamics of impedance values of the small and large intestine, parietal peritoneum, and greater omentum was analyzed during different periods of experimental acute intestinal obstruction. The impedance was below the normal, which indicated progressive microcirculatory disorders and necrosis of the intestinal wall. The histomorphological picture of healing of anastomoses created after resection of the intestine with consideration for bioimpedance values and of anastomoses created after resection of the intestine in a priori viable tissues virtually did not differ.

[Experimental substantiation of use of sodium hypochlorite and ozone at a formation of intestinal anastomosis in conditions of acute intestinal obstruction and peritonitis].

Presented are the results of experimental research on 144 animals (the rats Wistar), on whom was carried out resection of a part of large intestine and a intestinal anastamosis was formed in the presents of acute intestinal obstruction and peritonitis. The sanitation of abdominal cavity in the basic group of animals (74) was performed using sodium hypochlorite solution and dissolved ozone. The intestinal lavage was carried out by dissolved ozone with the subsequent introduction of ozonized oil Ozonide in the area of intestinal anastamosis. The combined application of ozone and sodium produces an expressed samative effect which leads to healing of intestinal anastamosis and decreases unstability of intestinal sutures and mortality.

Can deformation of a polymer film with a rigid coating model geophysical processes?

The structural and mechanical behavior of polymer films with a thin rigid coating is analyzed. The behavior of such systems under applied stress is accompanied by the formation of a regular wavy surface relief and by regular fragmentation of the coating. The above phenomena are shown to be universal. Both phenomena (stress-induced development of a regular wavy surface relief and regular fragmentation of the coating) are provided by the specific features of mechanical stress transfer from a compliant soft support to a rigid thin coating. The above phenomena are associated with a specific structure of the system, which is referred to as "a rigid coating on a soft substratum" system (RCSS). Surface microrelief in RCSS systems is similar to the ocean floor relief in the vicinity of mid-oceanic ridges. Thus, the complex system composed of a young oceanic crust and upper Earth's mantle may be considered as typically "a solid coating on a soft substratum" system. Specific features of the ocean floor relief are analyzed in terms of the approach advanced for the description of the structural mechanical behavior of polymer films with a rigid coating. This analysis allowed to estimate the strength of an ocean floor.

[Seasonal patterns of breast tumor growth in Far North residents].

Earlier, we established a relationship between sex hormone receptor concentration in tumor and 5-year survival, on the one hand, and seasonality, on the other. The parameters showed a distinct 6-month cycle. That pointed to certain environmental factors which could synchronize hormone-dependent tumor process in the breast of women living in the North. The present study is concerned with a relationship of 6-month rhythm of tumor growth and latitude of residence. Said rhythm was reliably identified as a parameter of 5-year survival in the Far North (68 deg. northern latitude, p < 0.001). Maximum values of 5-year survival were registered in those diagnosed with cancer in winter or summer, while those diagnosed in spring or fall had unfavorable prognosis. Northern magnetic storms recur at 6-month intervals and most frequently in spring and fall. Electromagnetic radiation is known to suppress melatonin production and, that might have stimulated tumor process. Therefore, it is most likely that solar electromagnetic radiation might synchronize hormone-dependent tumor process in women resident in the North.

[The factors affecting the level of ovarian hormone receptors in breast tumors in women]. / Faktory, vliiaiushchie na soderzhanie retseptorov ovarial'nykh gormonov v opukholiakh molochnoi zhelezy u zhenshchin.

We studied the level of estradiol and progesterone receptors in breast tumors of female patients. We have shown that the level of these receptors in tumors depends on whether the tumour is present in the left or right breast, the age of the patient, and the season of the year.

[Application of plasma scalpel for cholecystectomy]. / Kholetsist'ektomiia s primeneniem plazmennogo skal'pelia.

Plasma scalpel SUPR-M was used in operative treatment of calculous cholecystitis. Two variants of cholecystectomy with plasma scalpel have been worked out in experiment. It was determined, that the influence of plasma spurt is innocuous for hepatic tissues, it helps to achieve complete demucosation of the mucous membrane of the gall bladder in atypical variants of cholecystectomy, prevents bleeding and bile leakage from the bladder bead in typical cholecytectomy. In clinics the operation procedures were carried out in 176 patients, in 20 of them cholecystectomy was performed atypically, leaving gall bladder wall, adjacent to hepatic surface, in place. In postoperative period were no complications connected with the use of plasma scalpel as well as there were no lethal outcomes. Long-term follow-up of the patients for 5 years showed favourable clinical effect.

[Proteins associated with nucleolar organizer regions: practical application in tumor histopathology and relationship to biological properties of the tumor]. / Belki, assotsiirovannye s zonami iadryshkovogo organizatora: prakticheskoe primenenie v onkomorfologii i sviaz' s biologicheskimi osobennostiami opukholi.

The argyrophilic staining of nucleolar organizer regions (AgNOR) has been found to be of increasing use in routine and experimental histopathology in the study of certain neoplastic lesions. The AgNOR reaction demonstrates the presence of argyrophilic non-histone proteins within NORs. The number of detectable NORs depends on several factors: the level of transcriptional activity, the number of NOR-bearing chromosomes in the karyotype, and the stage of the cell cycle in which they are sought. In man, five chromosomes have NORs, and these areas are the sites which hybridize with rRNA and are of importance with respect to the ultimate synthesis of protein. The results of AgNORs might be more informative if this technique would be applied simultaneously in cytological and histological specimens for each patient. It may also be important to examine the AgNORs profiles in stromal cells.

[Characteristics of the morphologic changes in an experimental suppurative wound of the perimandibular soft tissues treated by some types of laser radiation]. / Osobennosti morfologicheskikh izmenenii v gnoinoi rane okolocheliustnykh miagkikh tkanei v éksperimente pri lechenii nekotorymi vidami lazernogo izlucheniia.

In rabbits isolated CO2 and He-Ne laser irradiation promotes early granulation of wounds and accelerates epithelialization with more complete restitution of the regenerated skin organ specificity. The best effect was achieved when combined laser irradiation was applied. This was further corroborated by the immunohistochemical investigation.

[Experimental validation of the expediency of the use of ultra-high frequency therapy in combination with antibacterial drugs in infiltrative tuberculosis of the lungs]. / Eksperimental'noe obosnovanie tselesobraznosti primeneniia UVCh-terapii v sochetanii s antibakterial'nymi preparatami pri infil'trativnom tuberkuleze legkikh.

The influence of the U.H.F. electric field in combination with specific antibacterial therapy on the character of morphological shifts, isoniazid accumulation, collagen fractional composition and tubercle bacilli population in the foci of infiltrative tuberculosis of the lungs was studied experimentally. The effect of this preformed physical factor on the process of tuberculosis was shown to be favourable. Under the action of the U.H.F. electric field microcirculation in the lungs improved, and the levels of isoniazid accumulation in tuberculosis foci increased 1.9-fold leading to decreasing of mycobacterial populations. By restricting specific inflammation, the U.H.F. electric field prevented excessive collagen formation.

[Role of modern methods of morphological research in the exact definition of the biological characteristics and morphogenesis of human breast cancer]. / Rol' sovremennykh metodov morfologicheskogo issledovaniia v utochnenii biologicheskikh osobennostei i morfogeneza raka molochnoi zhelezy cheloveka.

Combined use of modern methods of morphologic investigation will allow one in every diagnosed case of breast carcinoma to determine its histogenesis, make a differential diagnosis. Knowledge of biological features of malignant cells will allow one to apply an individual approach to treatment and prognosis. To clarify the morphogenesis of breast carcinoma, it is important to study the stromal component, as parenchymal-stromal relationship is a fundamental link in structural homeostasis.