Structure and histone composition of chromatin in Physarum polycephalum]

In Physarum polycephalum several degrees of organisation of deoxyribonucleoprotein fibres were found. The complexes of histones and the DNA duplex seem to "be packed" at first into a 100 A fibre and then into a 200 A fibre of DNP. In Ph. polycephalum the electrophoretic mobilities of histone fractions 4 and 6 are comparable to that of fractions f3/f2b and f2a1 of calf thymus, resp. Histone fractions 3 and 5 move a bit faster than fractions f1 and f2a2, resp. Thus, the myxomycete P. polycephalum is similar to higher eukaryotes as concerns the ultrastructure of chromatin and electrophoretic properties of histones.     

Stimulation of luminescence of mycelium of luminous fungus Neonothopanus nambi by ionizing radiation

The luminescent system of higher luminous fungi is not fully understood and the enzyme/substrate pair of the light emission reaction has not been isolated. It was suggested that luminescence of fungi involves oxidase‐type enzymes, and reactive oxygen species are important for fungal light production. Generation of reactive oxygen species can be stimulated by ionizing irradiation, which has not been studied for luminous fungi. We report the effect of X‐irradiation on the luminescence of fungus Neonothopanus nambi. Experiments were performed with mycelium on a home‐built setup based on an X‐ray tube and monochromator/photomultiplier tube. Application of X‐rays does not change the emission spectrum, but after approximately 20 min of continuous irradiation, light production from unsupported mycelium starts growing and increases up to approximately five times. After peaking, its level decreases irrespective of the presence of X‐irradiation. After staying at a certain level, light production collapses to zero, which is not related to the drying of the mycelium or thermal impact of radiation. The observed shape of kinetics is characteristic of a multistage and/or chain reaction. The time profile of light production must reflect the current levels of radicals present in the system and/or the activity of enzyme complexes involved in light production. Copyright © 2014 John Wiley & Sons, Ltd.     

beta-Glucanases of Geotrichum candidum

The formation of (1-4)-, (1-3)- and (1-6)-beta-glucanases and beta-glucosidases was studied during the growth of the fungus Geotrichum candidum under the conditions of submerged cultivation in a medium optimal for the production of cellulolytic enzymes. Endo-(1-4)-beta-glucanases and C1 enzyme, as well as (1-3)- and (1-6)-beta-glucanases appeared in the medium as soon as by the 45th hour of growth. However, the maximal concentration of the enzymes in the medium was observed at different periods of the fermentation: between 75th and 105th, 70th and 95th, 55th and 100th, 80th and 105th hours, respectively. The content of the enzymes abruptly decreased by the 160th hour of the growth. The activity of beta-glucosidases, which was low at the beginning of the growth, sharply increased by the 70th hour and remained at the same level by the 160th hour of the growth. The accumulation of beta-glucanases was an uneven process, consistent with irregular changes in the content of DNA and protein in the biomass. The isoelectric points of beta-glucanases and beta-glucosidases were studied in the filtrate of the cultural broth after 96 h of the cultivation. The high activity of endo-(1-4)-beta-glucanase was found at the pH 4.6, 4.1 and 3.8; its low activity was detected at the pH 6.4, 3.2, 1.6 and 1.3. Other glucanases behaved also as acid proteins. During isoelectric focusing, (1-3)-beta-glucanase showed the peaks of activity at the pH 4.4, 4.0, 3.8 and 2.9; (1-6)-beta-glucanase, at the pH 5.0, 3.7, 3.5, 3.1 and 2.0; beta-glucosidases were distributed over a broad pH range from 6.7 to 2.0, with the maximal activity at the pH 6.2, 4.8 and 3.7.     

State of Human Papilloma Virus DNA in Cervical Carcinomas

Cervical carcinoma is etiologically associated with the human papilloma virus (HPV), HPV 16 and HPV 18 being the most common. Viral DNA is thought to persist mostly in the episomal form in early tumor development, and in the integrated form in carcinomas. This assumption was checked with a new method that discriminated between RNAs transcribed from episomal and integrated HPV DNAs. Both forms were detected in carcinomas of Russian patients regardless of the disease stage. The data were verified by two other methods. RNA with sequences of the HPV transforming gene E7proved to be transcribed from either DNA form. The results suggest that HPV integration is not crucial for carcinoma progression.     

The Effect of Polyoxyethylene–Polyoxypropylene Triblock Copolymers on the Loading Degree of Poly-(Lactic-co-Glycolic Acid) Copolymer-Based Microparticles Containing Chlorin e6 and Ethidium Bromide in Mesenchymal Stem Cells

Biophysics - The effect of different polyoxyethylene–polyoxypropylene triblock copolymers, their concentration, and mode of action on the loading of poly-(lactic-co-glycolic acid)...     

Status of the human DNA papillomavirus in cervical tumors]

Cervical carcinoma is etiologically associated with the human papilloma virus (HPV), HPV 16 and HPV 18 being the most common. Viral DNA is thought to persist mostly in the episomal form in early tumor development, and in the integrated form in carcinomas. This assumption was checked with a new method that discriminated between RNAs transcribed from episomal and integrated HPV DNAs. Both forms were detected in carcinomas of Russian patients regardless of the disease stage. The data were verified by two other methods. RNA with sequences of the HPV transforming gene E7 proved to be transcribed from either DNA form. The results suggest that HPV integration is not crucial for carcinoma progression.