Spherically symmetrical strata ͑striation͒ in a dc glow discharge were discovered. Experiments were carried out in a low-pressure steel chamber that served as a cathode. An anode was placed in the center of the chamber. The stratification of the glow discharge was observed in some molecular gases: air, N 2 , O 2 , CO 2 , and acetone vapor. A simple relation between strata radii and their number r n /r nϪ1 ϭ␣, where ␣ϭ1.4-2 ͑depending on gas composition͒, were found. Gas pressure dependences of strata radii were measured. The values of bulk charge and electric potential radial distributions were estimated. A simplified Boltzmann equation for the electron energy distribution function ͑EEDF͒ in spherical geometry was used for theoretical consideration. The so-called ''black wall law'' assumption was used in the collisional integral. An analytical solution for the isotropic part of EEDF was obtained. The existence of converging and decaying stagnant waves reproducing the variation of the observed strata radii was shown. ͓S1063-651X͑98͒03709-X͔ PACS number͑s͒: 51.50.ϩv, 52.80.Hc

Protein–lipid interactions are important for protein targeting, signal transduction, lipid transport, and the maintenance of cellular compartments and membranes. Specific lipid‐binding protein domains, such as PH, FYVE, PX, PHD, C2 and SEC14 homology domains, mediate interactions between proteins and specific phospholipids. We recently cloned a 45‐kDa protein from rat olfactory epithelium, which is homologous to the yeast Sec14p phosphatidylinositol (PtdIns) transfer protein and we report here that this protein binds to PtdIns(3,4,5)P3 and far weaker to less phosphorylated derivatives of PtdIns. Expression of the p45 protein in COS‐1 cells resulted in accumulation of the protein in secretory vesicles and in the extracellular space. The secreted material contained PtdIns(3,4,5)P3. Our findings are the first report of a Sec14p‐like protein involved in transport out of a cell and, to the best of our knowledge, inositol‐containing phospholipids have not previously been detected in the extracellular space. Our findings suggest that p45 and phosphoinositides may participate in the formation of the protective mucus on nasal epithelium.

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The object of the present study is the verification of a new approach to the design of the active truncated forms of enzymes. The method is based on a new way of investigating the protein sequences--the ANalysis of Informational Structure (ANIS). The analysis of informational structure allows to determine the hierarchically organized structures (IDIC-trees) formed by the sites with the Increased Degree of Informational Coordination between residues. The proposed approach involves the consequent removal of the fragments corresponding to the individual IDIC-trees from the wild-type enzyme sequences. The described procedure was applied to the design of the active truncated form of human 1-CYS peroxiredoxin (PrxVI). Two variants of the PrxVI truncated sequences were proposed according to ANIS method. These truncated forms of the enzyme were expressed in E. coli and purified. The respective antioxidant activities were measured. It was shown that one of the truncated recombinant proteins retains more than 90% of the wild-type PrxVI enzymatic activity. According to the results of our study we can assume that ANIS method can be an effective tool for the design of the active truncated forms of the enzymes or the chimeric proteins which combine the enzymatic activities of their wild-type prototypes.