Manganese transport into yeast cells is energy-dependent. It is dependent on endogenous sources of energy and is inhibited by olygomycin (12.5 -25 kg/ml), 2,4-dinitrophenol (1 mM), 2-deoxyglucose (1 -50 mM) and sodium azide (1 -10 mM), but is stimulated by cyanide and glucose. The stimulating effect of glucose is eliminated by N-ethylmaleimide and iodoacetate, which apparently inhibit the transport of glucose itself. About 75% of the manganese accumulated in the presence of glucose is found in yeast protoplasts and nearly 25% in the cell walls. A major portion of the accumulated manganese is found in vacuoles. The concentration of osmotically free manganese in the cytosol did not exceed 2 m M , but the concentration in vacuoles was up to 14mM. The tonoplast is assumed to have a transport system for divalent cations, thereby regulating their concentration in the cytosol.The transport of bivalent manganese ions has long attracted the attention of investigators [l -41.Data have been obtained which support the hypothesis that a M 2 +-dependent plasmolemma ATPase provides energy for this process; this enzyme uses ATP only of glycolytic origin [4-61. The state of the accumulated ions (free and bound manganese) and also their distribution inside the yeast cells have not been studied yet.Recently using a cytochemical method of analysis we found that magnesium ions are localized in yeast vacuoles and that the accumulated manganese is also concentrated in these organelles [7]. An independent biochemical approach supported the idea that a considerable portion of the total magnesium (up to 40%) is localized in yeast vacuoles [8,9]. In this work we have used this approach in order to study the distribution of manganese in the cells of Saccharomyces carhbergensis. In addition, the energy-dependent character of manganese accumulation by yeast was demonstrated. Microorgan ismsAll the experiments were carried out on the yeasts Saccharomyces cereuisiae (strain IBPM-355) and Succharomyces carlsbergensis (strain IBPM-366). Yeasts were grown in flasks in Reader medium at 29 "C. Inoculation was carried out with 24-h innocula; after 5 h the cells were collected by centrifugation, and were washed with distilled water. Then they were incubated for 60 min in a medium containing potassium phosphate (0.33 M) and glucose (0.1 M) at 30 "C or 37 "C under the same shaking conditions as during growth. Then the cells were washed with distilled water and were used for experiments to investigate the accumulation of manganese ions. The accumulation of manganese was carried out for 45 min at 30 "C, pH 5.5 and under continuous shaking. The concentration of manganese sulphate was 3 mM and glucose (if added) 100 mM [3].Usually cells were separated from medium by centrifugation followed by washing with water.In the experiments on the influence of different inhibitors on manganese uptake, this process was stopped at specific times by the addition of La3+ ions to a final concentration 0.3 mM. Then the cells were separated by centrifugation and washed with...

Gas discharge plasma inactivation of microorganisms at low (close to ambient) temperature is a promising area of investigation that is attracting widespread interest. This paper describes atmospheric-pressure, nonthermal plasma (NTP) methods for cold sterilization of liquids and thermal sensitive surfaces. These methods are based on the use of direct current (DC) gas discharge plasma sources fed with steady-state high voltage. Parameters characterizing the plasma sources used (plasma-forming gas, gas flow rate, electric power consumed, etc.) are given. The results for plasma sterilization of different microorganisms (vegetative cells, spores, fungi, biofilms) are presented. An empirical mathematical approach is developed for describing NTP inactivation of microorganisms. This approach takes into account not only the destruction of different components of the cells, but their reparation as well.

The content of total, bound and osmotically free magnesium was estimated in various fungi and in the yeast Saccharomyces cerevisiae. Total magnesium increases at lower growth rates of Endomyces magnusii and Penicillium chrysogenum 140A as well as during the logarithmic stage of growth of Penicillium chrysogenum Q-176. The binding of magnesium requires orthophosphate, decreasing during lack of external phosphate when the intracellular concentration of free magnesium rises. The fungi were found to contain a novel form of bound magnesium, a polymeric magnesium orthophosphate (PO Mg), which appears to take part in the control of free magnesium level in Penicillium chrysogenum Q-176. The level of free magnesium is proportional to the growth rate of Endomyces magnusii and Penicillium chrysogenum Q-176 and 140A. Total, as well as free, magnesium changes less than three-fold as external Mg concentration is changed 13,000-fold. The magnesium is taken up against concentration gradients of 1 : 25 to 1 : 1300, the metal being distributed non-uniformly in the cells of Saccharomyces cerevisiae.

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Non-thermal plasma jet formed by self-running pulsed-periodical high-current spark generator (PPSG) was used for atmospheric pressure inactivation of microorganisms including biofi lms. A distinctive feature of the PPSG is a formation of transient hot plasma clouds (plasma bullets) periodically fl ying out to the target. We experimented with model biofi lms of E. coli and Bacillus subtilis monocultures which were grown on agar and surfaces of steel and polypropylene coupons. High effi ciency of plasma inactivation was demonstrated. This effect is associated primarily with an interaction of transient hot plasma clouds with biofi lms. Besides complete or partial degradation of the cell membrane, weakening of the cell wall of E.coli culture by active plasma was found.