Adenovirus serotype determines association and localization of the large E1B tumor antigen with cellular tumor antigen p53 in transformed cells.

The distribution and stability of the cellular tumor antigen p53 were studied in baby rat kidney cells transformed by region E1 sequences of nononcogenic adenovirus (Ad) type 5 (Ad5) or oncogenic type 12 (Ad12). In transformed cells expressing the large E1B T antigen of Ad5, p53 was associated with this T antigen. The complexed proteins were concentrated in a cytoplasmic body, which has been shown to consist of a cluster of 8-nm filaments (A. Zantema et al., Virology 142:44-58, 1985). In transformed cells expressing the E1B region of Ad12, however, no association between the viral large T antigen and p53 was detectable. In the latter case, both proteins were found almost exclusively in the nucleus. The stability of p53 in both Ad5- and Ad12-transformed cells was increased relative to that in primary cells or cells immortalized by the E1A region only. Thus, the increased stability of p53 in Ad-transformed cells is not caused by association with a viral T antigen, but it correlates with expression of E1B and with morphological transformation.     

Stability of α-chymotrypsin conjugated with poly (ethylene glycols) and proxanols at high temperature and in watercosolvent mixtures

Summary -Chymotrypsin has been modified with poly(ethylene glycols) and proxanols, block-copolymers of poly(propylene oxide) and poly(ethylene oxide). These conjugates were several-fold more thermostable and showed high catalytic activity at elevated concentrations of water-miscible organic cosolvents (alcohols and dimethyl sulfoxide) which caused inactivation of free (non-modified) -chymotrypsin.     

Marker-Dependent Recombination in T4 Bacteriophage. I. Outline of the Phenomenon and Evidence Suggesting a Mismatch Repair Mechanism

In standard crosses, some rIIB mutants of T4 phage were found to be susceptible to an extra recombination mechanism to which the other mutants were much less susceptible. The following observations were interpreted as evidence for the mismatch-repair nature of the phenomenon: (1) Marker-dependent recombination generates exclusively double exchanges at both sides of the marker. (2) Marker-dependent recombination is highly sensitive to DNA base sequence at the site of the marker and to that at the corresponding site on the chromosome of the other parent. (3) Within certain limits, the contribution of the marker-dependent mechanism to the total recombination frequency is distance-independent and thus constitutes a constant component.     

BSA Adsorption on Porous Scaffolds Prepared from BioPEGylated Poly(3-Hydroxybutyrate)

Porous scaffolds for tissue engineering have been prepared from poly(3-hydroxybutyrate) (PHB) and a copolymer of poly(3-hydroxybutyrate) and polyethylene glycol (PHB-PEG) produced by bioPEGylation. The morphology of the scaffolds and their capacity for adsorption of the model protein bovine serum albumin (BSA) have been studied. Scaffolds produced from bioPEGylated PHB adsorbed more BSA, whereas the share of protein irreversibly adsorbed on these scaffolds was significantly lower (33%) than in the case of PHB homopolymer-based scaffolds (47%). The effect of protein adsorption on scaffold biocompatibility in vitro was tested in an experiment that involved the cultivation of fibroblasts (line COS-1) on the scaffolds. PHB-PEG scaffolds had a higher capacity for supporting cell growth than PHB-based scaffolds. Thus, the bioPEGylated PHB-based polymer scaffolds developed in the present study have considerable potential for use in soft tissue engineering.     

Night sleep structure in the cases of disturbance of blood supply in the internal carotid artery pool

The study examines correlation between the degree of stenosis of the internal carotid artery (ICA) and the night sleep parameters. The possible neurophysiological mechanisms of sleep disorder in blood flow disturbances in the carotid system are also discussed. Twenty-four patients (19 men and 5 women) were examined, including 6 cases of 50% ICA stenosis, 7 cases of 50–70% ICA stenosis; and 11 cases of ICA occlusion. A polygraphic study of night sleep was conducted and the sleep stages were analyzed. The patients filled in the quality of sleep questionnaire with the presence of the somnolence scoring system. In order to assess brain perfusion, single-photon emission CT imaging of the brain was performed. The results of the study showed that the night sleep structure in the cases of 50% ICA stenosis was unchanged: all the sleep phases and stages whose quantitative parameters corresponded to the reference normal data were recorded, or only stage II sleep representation declined; in the cases of 50–70% ICA stenosis, predominantly stage II sleep and slow-wave sleep were compromised; in patients with ICA occlusion, slow-wave sleep and REM-sleep (45% of cases) were disturbed.     

Teichoic acids of three type strains of the Bacillus subtilis group, Bacillus mojavensis VKM B-2650, Bacillus amyloliquefaciens subsp. amyloliquefaciens VKM B-2582, and Bacillus sonorensis VKM B-2652

Cell walls of three type strains of the Bacillus subtilis group, Bacillus mojavensis VKM B-2650, Bacillus amyloliquefaciens subsp. amyloliquefaciens VKM B-2582, and Bacillus sonorensis VKM B-2652, are characterized by the individual set of teichoic acids. All strains contained 1,3-poly(glycerol phosphates), unsubstituted, acylated with D-alanine, and glycosylated. The latter differ in the nature of the monosaccharide residue. Teichoic acids of B. mojavensis VKM B-2650^T and B. amyloliquefaciens subsp. amyloliquefaciens VKM B-2582^T contained α-glucopyranose, while those of B. sonorensis VKM B-2652^T contained β-glucopyranose and N-acetyl-α-D-glucosamine. Moreover, cell walls of B. mojavensis VKM B-2650^T contained a teichoic acid of poly(glycosylglycerol phosphate) nature with the following structure of the repeating unit: -4)-α-D-α-D-GlcpNAc-(1 → 3)]-Glcp-(1 → 2)-sn-Gro-(3-P-. The type strains have been characterized according to the composition of cell wall sugars and polyols. Application of teichoic acids (set and structure) as chemotaxonomic characteristics is discussed for six type strains of the Bacillus subtilis group. Polymer structures were determined by chemical and NMR spectroscopic techniques.     

Disaccharide 1-phosphate polymers of some representatives of the Bacillus subtilis group

Disaccharide 1-phosphate polymers as well as teichoic acids of various structures have been found in the cell walls of the representatives of the Bacillus subtilis group, namely Bacillus subtilis subsp. spizizenii VKM B-720 and VKM B-916, B. subtilis VKM B-517, and Bacillus vallismortis VKM B-2653^T. Disaccharide 1-phosphate polymers are composed of repeating units of the following structure: -P-4)-β-D-GlcpNAc-(1→6)-α-D-Galp-(1-, the N-acetylglucosamine residues are partially acetylated at positions O3 and O6 (VKM B-720 and VKM B-916); -P-4)-β-D-Glcp-(1→6)-α-D-GlcpNAc-(1-, the glucopyranose residues are partially acetylated at positions O2 or O3 (VKM B-517); -P-6)-α-D-GlcpNH ₃ ⁺ /α-D-GlcpNAc-(1→2)-α-D-Glcp-(1-, the N-acetylglucosamine residues are partially deacetylated (VKM B-2653^T). The structures of the two last disaccharide 1-phosphate polymers have not been reported so far for Gram-positive bacteria. The teichoic acids in the studied strains are O-D-alanyl-1,5-poly(ribitol phosphates) substituted with β-D-glucopyranose (VKM B-517, VKM B-720, VKM B-916) or 2-acetamido-2-deoxy-β-D-glucopyranose (VKM B-2653^T). The structures of the phosphate-containing polymers have been studied by chemical methods and by NMR spectroscopy.     

STING Millennium Suite: integrated software for extensive analyses of 3d structures of proteins and their complexes

Background  

The integration of many aspects of protein/DNA structure analysis is an important requirement for software products in general area of structural bioinformatics. In fact, there are too few software packages on the internet which can be described as successful in this respect. We might say that what is still missing is publicly available, web based software for interactive analysis of the sequence/structure/function of proteins and their complexes with DNA and ligands. Some of existing software packages do have certain level of integration and do offer analysis of several structure related parameters, however not to the extent generally demanded by a user.