Ethylene-Induced Activation of Xylanase in Adventitious Roots of Maize as a Response to the Stress Effect of Root Submersion

Submersion of roots of ten-day-old maize (Zea maysL.) seedlings was accompanied by a decrease in pO₂and an increase in pCO₂of the medium adjacent to the roots. These changes stimulated ethylene evolution in intact plants. Enhanced biosynthesis of ethylene was accompanied by xylanase activation in adventitious roots. As a result, an enhanced formation of aerenchyma was observed in the cortex of adventitious roots. Therefore, these processes resulted in the development of a ventilation system by which O₂can reach the root system exposed to hypoxia. The volume of aerenchyma was assessed by the volume of gas cavities (porosity). In contrast to the main root, the growth of adventitious roots was not inhibited under these conditions. Enlargement of the stem base and increase in the number of aerenchymatous adventitious roots facilitated the oxygen supply to the submerged organs of the plants.     

Use of the indirect hemagglutination reaction for detecting antibodies to Pseudomonas pyocyanea in acute suppurative destructive pneumonia]

No less than 4-fold increase in the antibody titres to Pseudomonas aeruginosa during the infectious process served as laboratory confirmation of its participation in the infectious process. In 49 of 91 patients hemagglutining titre exceeded the diagnostic one (1:640). In 9 patients (chiefly in infants) hemagglutinin titre remained low, but there was a rise of antibody level to Pseudomonas aeruginosa during the disease. High hemagglutinin titres were noted in 12 patients on admission to the clinic, with reduction of the antibody titres at the late periods of the disease. Antibody titres remained unchanged during the disease in 15 patients. In 3 cases the indirect hemagglutination test was assesed as negative. In the rest of the patients hemagglutinin titres varied within the range of the diagnostic titre. Thus, the indirect hemagglutination test with erythrocytic diagnostic agent permitting to determine antibodies to Pseudomonas aeruginosa could be used at the clinic in combination with bacteriological and other investigations for establishing etiology of the destructive process.     

Low-Molecular-Weight Components of Luminescent Reaction of the Siberian Enchytraeid <Emphasis Type="Italic">Henlea</Emphasis> sp.

The first results of the study of chromatographic and spectral properties of the detected lowmolecular-weight activators, putative emitters in the luminescent reaction of Siberian enchytraeid Henlea sp., are presented.     

Isolation and Purification of Fungal Luciferase from <Emphasis Type="Italic">Neonothopanus nimbi</Emphasis>

This is the first study to obtain a high-purity luciferase from the fungus Neonothopanus nambi biomass that is suitable for subsequent sequencing.     

Structure of fungal oxyluciferin,the product of the bioluminescence reaction

The structure of fungal oxyluciferin was determined, the enzymatic bioluminescence reaction under substrate saturation conditions with discrete monitoring of formed products was conducted, and the structures of the end products of the reaction were established. On the basis of these studies, the scheme of oxyluciferin degradation to the end products was developed. The structure of fungal oxyluciferin was confirmed by counter synthesis.     

Sporophyte-gametophyte interactions between anther and male gametophyte in petunia

Sporophyte-gametophyte interactions between anther and male gametophyte were investigated in two (fertile and sterile) clones of petunia (Petunia hybrida L.) with different reproductive strategies. Structural and functional reorganization of sporophyte tissues in the developing anther of fertile clone is closely coordinated with each of the successive stages of male gametophyte development (from meiosis to the formation of binuclear pollen) and comprises not only destruction of tapetum and three middle layers of the wall but also an activation of gas exchange and a rise in the content of sugars (sucrose, fructose, and glucose). In sterile clone, degradation of tapetum and anomalies in the development of sporogenic tissue were simultaneously observed in the prophase of meiosis. The death of microsporocytes and degeneration of tapetum were accompanied by a decrease in the level of sucrose delivered to the anther tissues and changes in the ratio between sucrose and hexoses in favor of glucose.     

A novel class of modular transporters for vitamins in prokaryotes

The specific and tightly controlled transport of numerous nutrients and metabolites across cellular membranes is crucial to all forms of life. However, many of the transporter proteins involved have yet to be identified, including the vitamin transporters in various human pathogens, whose growth depends strictly on vitamin uptake. Comparative analysis of the ever-growing collection of microbial genomes coupled with experimental validation enables the discovery of such transporters. Here, we used this approach to discover an abundant class of vitamin transporters in prokaryotes with an unprecedented architecture. These transporters have energy-coupling modules comprised of a conserved transmembrane protein and two nucleotide binding proteins similar to those of ATP binding cassette (ABC) transporters, but unlike ABC transporters, they use small integral membrane proteins to capture specific substrates. We identified 21 families of these substrate capture proteins, each with a different specificity predicted by genome context analyses. Roughly half of the substrate capture proteins (335 cases) have a dedicated energizing module, but in 459 cases distributed among almost 100 gram-positive bacteria, including numerous human pathogens, different and unrelated substrate capture proteins share the same energy-coupling module. The shared use of energy-coupling modules was experimentally confirmed for folate, thiamine, and riboflavin transporters. We propose the name energy-coupling factor transporters for the new class of membrane transporters.     

Societal Risk Perception in Present Day Russia

The study analyzed new information regarding the way in which present day Russians (living in Moscow or Tula) perceive societal risks. The main concerns of Russians in year 2003 were essentially the same ones that were identified in previous studies conducted on Western samples: violence, sex, and addiction-type hazards received the highest risk ratings. Women's mean risk judgments were systematically higher than men's mean judgments, and older participants' mean judgments were higher than younger participants' mean judgments regarding domestic hazards. Technically trained people perceived higher societal risk than people with training in the humanities, but the difference between people with technical training and people trained in the humanities was more accentuated among younger people than among the elderly. Also, men living in Tula perceived themselves as less exposed to risks of violence than women living in Tula and both men and women living in Moscow.