Induction of salt tolerance in Bacillus subtilis IFO 3025.

Salt tolerance was induced in Bacillus subtilis IFO 3025 cells when a moderate osmotic stress was imposed by incubation in the presence of compatible solutes and 0.5 M NaCl or 0.8 M sorbitol.

Effect of compatible solutes on the respiratory activity and growth of Escherichia coli K-12 under NaCl stress.

The respiratory activity of Escherichia coli K-12 was inhibited by high NaCl concentrations. The addition of compatible solutes such as proline and ectoine led to the recovery of the respiration of E. coli K-12 inhibited by 1 M NaCl to a similar extent as did the addition of glycine betaine.

Growth of Escherichia coli ATCC 9637 through the uptake of compatible solutes at high osmolarity.

The growth rate of Escherichia coli ATCC 9637 was determined in a chemically defined (CD) medium with high osmolarity, 1-1.2 M. The addition of ectoine or glycine betaine to the medium resulted in a significant stimulation of growth rate for this strain.

Accumulation of ectoine in the halotolerant Brevibacterium sp. JCM 6894.

The optimum conditions for the intracellular synthesis of the cyclic amino acid ectoine (1,4,5,6-tetrahydro-2-methyl-4-pyridine carboxylic acid) were determined using the halotolerant Brevibacterium sp. JCM 6894. The amount of ectoine synthesized in cells was quantitatively determined after extraction from cells grown under various conditions, such as different external osmolarities, incubation times, and types and concentrations of nutrients in the medium.

Simultaneous determination of iodide and iodate in seawater by transient isotachophoresis-capillary zone electrophoresis with artificial seawater as the background electrolyte.

We developed capillary zone electrophoresis with transient isotachophoresis (ITP) as an on-line concentration procedure for simultaneous determination of iodide and iodate in seawater. The effective mobility of iodide was decreased by addition of 20 mM cetyltrimethylammonium chloride to an artificial seawater background electrolyte so that transient ITP functioned for both iodide and iodate. Limits of detection for iodide and iodate were 4.

Highly sensitive capillary zone electrophoresis with artificial seawater as the background electrolyte and transient isotachophoresis as the on-line concentration procedure for simultaneous determination of nitrite and nitrate in seawater.

Transient isotachophoresis-capillary zone electrophoresis with artificial seawater as the background electrolyte (BGE) was improved to further lower the limit of detection (LOD) for determination of nitrite and nitrate in seawater. By lowering the pH of BGE, the difference between effective mobility of nitrite and that of nitrate increased, thereby permitting increased sample volumes to be tolerated and their LOD values to decrease. Artificial seawater with pH adjusted to 3.

Capillary zone electrophoretic determination of iodide in seawater using transient isotachophoresis with artificial seawater as the background electrolyte.

We describe an application of capillary zone electrophoresis (CZE) with transient isotachophoresis (ITP) as the on-line concentration procedure for the determination of iodide in seawater. The effective mobility of iodide was decreased by the addition of 10 mM cetyltrimethylammonium chloride (CTAC) to an artificial seawater background electrolyte (BGE) so that transient ITP functioned and iodide was separated from other coexisting anions such as bromide, nitrite, and nitrate in seawater samples. After sample injection, 600 mM acetate was separately injected into the capillary as the terminating ion to generate transient ITP.

Optimum conditions for effective use of the terminating ion in transient isotachophoresis for capillary zone electrophoretic determination of nitrite and nitrate in seawater, with artificial seawater as background electrolyte.

We have examined transient isotachophoresis (ITP) conditions, e.g. the nature of the terminating ion, its concentration, and the injection procedure, to improve the limit of detection (LOD) for determination of nitrite and nitrate in seawater by capillary zone electrophoresis (CZE).

Possible role of contact following in the generation of coherent motion of Dictyostelium cells.

After aggregation by chemotaxis, cells of the cellular slime mold Dictyostelium discoideum form a multicellular structure and show coherent motion such as vortices. Here, we present a mathematical model to explain both aggregation and coherent motion of cells in two-dimensional space. The model incorporates chemotactic response of cells and the cell's property, called "contact following", to follow the other cells with which they are in contact.

Determination of nitrite and nitrate in a proposed certified reference material for nutrients in seawater by capillary zone electrophoresis with artificial seawater as the background electrolyte using transient isotachophoresis.

We describe a combination of selected ions as a terminating ion which is useful for transient isotachophoresis (ITP) in capillary zone electrophoresis (CZE) for the determination of nitrite and nitrate in seawater. In addition to 150 mM sulfate as the principal terminating ion, 10 mM bromate was added to a sample solution as the additional terminating ion. Artificial seawater containing 3 mM cetyltrimethylammonium chloride (CTAC) was adopted as a background electrolyte (BGE).

Interrelation between synthesis and uptake of ectoine for the growth of the halotolerant Brevibacterium species JCM 6894 at high osmolarity.

The growth of a halotolerant Brevibacterium sp. JCM 6894 was examined in the presence of compatible solutes such as glycine betaine, ectoine (2-methyl-4-carboxy-3,4,5,6-tetrahydropyrimidine) and ectoine derivatives. The effect of competition between their uptake and synthesis in the cells was subjected to osmotic shift towards the higher salinity.

Simultaneous determination of bromide, nitrite and nitrate ions in seawater by capillary zone electrophoresis using artificial seawater as the carrier solution.

We describe capillary zone electrophoresis (CZE) for the simultaneous determination of bromide, nitrite and nitrate ions in seawater. Artificial seawater was adopted as the carrier solution to eliminate the interference of high concentrations of salts in seawater. The artificial seawater was free from bromide ion to enable the determination of bromide ion in a sample solution.

Application of capillary electrophoresis to the analysis of inorganic ions in environmental samples.

A comprehensive review is presented of the state-of-the-art of capillary electrophoresis for application to the analysis of inorganic species, mainly ions, in environmental samples. This brief review covers the developments principally in sensitivity and matrix interference for the determination of inorganic ions in the following samples: drinking, mineral, surface, and ground waters, rainwater, snow, seawater, brine and waste waters, aerosol, and others. References published mainly from 1995 to 1997 were summarized in this review.

Intracellular changes in ions and organic solutes in halotolerant brevibacterium sp. Strain JCM 6894 after exposure to hyperosmotic shock.

In the present study we aimed to observe the intracellular responses when there was a hyperosmotic shock with a large shift in ionic strength in nutrient-rich and nutrient-poor external environments in order to clarify the availability of substrates. To do this, we used the halotolerant organism Brevibacterium sp. strain JCM 6894, which is able to grow in the presence of a wide range of salt concentrations.

Determination of magnesium and calcium ions in seawater by capillary zone electrophoresis.

Capillary zone electrophoresis is proposed for the determination of magnesium and calcium ions in seawater. A carrier solution containing EDTA was adopted for the complexation of these ions and the effect of sodium chloride concentration in the sample solutions on the results was examined. It was found that magnesium and calcium ions could be determined without any pretreatment by injecting 100-fold diluted seawater samples.

23Na NMR spectroscopy of free Na+ in the halotolerant bacterium Brevibacterium sp. and Escherichia coli.

23Na NMR spectroscopy was used to determine free Na+ concentrations in a halotolerant bacterium, Brevibacterium sp., and Escherichia coli. The internal Na+ concentration of both strains depended little on the growth phases and was unchanged after 5 d storage at 2 degrees C.

Lethal effect of carbonyl cyanide m-chlorophenylhydrazone on Escherichia coli and a halotolerant Brevibacterium species.

An attempt was made to examine quantitatively the survival of Escherichia coli and the halotolerant Brevibacterium species, as a function of the exposure time to carbonyl cyanide m-chlorophenylhydrazone (CCCP), a proton conductor. Growth rates, viability, and protein concentrations of E. coli grown in the absence of glucose were unaffected by the addition of 100 microM CCCP.

Domains of Attraction of Multivariate Extreme Value Distributions.

Some necessary and sufficient conditions for domains of attraction of multivariate extreme value distributions are shown by using dependence functions. The joint asymptotic distribution of multivariate extreme statistics is also shown.

Incident angle dependence of proton response of CR-39 (TS-16) track detector.

The proton response of the TS-16 type of CR-39 plastic nuclear track detector has been studied with accelerated and fast neutron induced protons in vacuum and in air. The diameters of etched tracks were measured as a function of etching time and the etch rate ratio and the etch induction layer were determined from the growth curve of the diameter using a variable etch rate ratio model. In the case of the accelerated protons in vacuum an anomalous incident angle dependence of the response is observed.

Double response to Stroop stimuli.

To reexamine Klein's 1964 findings we carried out two experiments on the double response made to Stroop stimuli. In Exp. 1 incongruent color-word stimuli were presented on a CRT online with a microcomputer.

Mechanism of decomposition of cyclic peroxides, 4-alkoxy-1,4-dihydro-2,3-benzodioxin-1-ols, to afford hydroxyl radical.

The decomposition of 4-alkoxy-1,4-dihydro-2,3-benzodioxin-1-ols (1, Bd) in aqueous media was examined. Increasing the water content of the medium accelerated the decomposition of 1 and increased the formation of the corresponding 2-formyl benzoic acid ester (2) as the decomposition product. Electron spin resonance (ESR) studies using dimethylpyrroline N-oxide (DMPO) as a spin trapping reagent had revealed that hydroxyl radicals are formed during the decomposition of 1 (Matsugo et al.

DNA strand scisson and cell-killing activity of hydroperoxynaphthalimide derivatives upon photoirradiation.

A series of hydroperoxynaphthalimides (1a-1c) and naphthaldiimide (2) that generate hydroxyl radical upon longer wavelength photoirradiation (366 nm) have been devised. They induce DNA strand break at low concentration upon photoirradiation which are inhibited in the presence of hydroxyl radical scavengers such as mannitol or sodium benzoate. The compound 2 showed a sequence specific DNA strand scission at -5'GG-sequence.