scholarly journals Studies on halotolerance in a moderately halophilic bacterium. Effect of betaine on salt resistance of the respiratory system

1968 ◽  
Vol 109 (4) ◽  
pp. 687-691 ◽  
Author(s):  
Dvora Rafaeli-Eshkol ◽  
Y. Avi-Dor
Keyword(s):  
Sodium Chloride ◽  
Respiratory Rate ◽  
Respiratory System ◽  
Chloride Concentration ◽  
Salt Resistance ◽  
High Salt ◽  
Salt Medium ◽  
Sodium Chloride Concentration ◽  
Moderately Halophilic ◽  
Low Salt

The role of betaine as a factor influencing the salt resistance of the respiratory system in resting cells of the moderately halophilic halotolerant bacterium Ba1 was studied. Betaine accelerated succinate oxidation in cells obtained from low-salt medium, and stimulation of the respiratory rate was stronger the higher the sodium chloride concentration in the assay medium. The stimulatory effect also depended on the ratio of betaine concentration to the amount of bacteria present. Accumulation of labelled betaine by the bacterial cells was demonstrated; like the respiratory stimulation, it was favourably influenced by an increase in the sodium chloride concentration of the medium. In cells harvested from a high-salt medium and washed with 2·0m-sodium chloride, betaine caused no increase in the respiratory rate, nor was the already high salt resistance of the respiratory system further improved by the addition of betaine. When, however, these cells lost their salt resistance as a result of washing in the absence of sodium chloride, betaine was able to restore it to its original level. In contrast with respiration in low-salt-grown bacteria, that in high-salt-grown cells was not affected by betaine, even after they were washed in the absence of sodium chloride, when the sodium chloride concentration was optimum.

scholarly journals Studies on halotolerance in a moderately halophilic bacterium. Effect of growth conditions on salt resistance of the respiratory system

1968 ◽  
Vol 109 (4) ◽  
pp. 679-685 ◽  
Author(s):  
Dvora Rafaeli-Eshkol
Keyword(s):  
Sodium Chloride ◽  
Respiratory System ◽  
Chloride Concentration ◽  
Growth Conditions ◽  
Salt Resistance ◽  
High Salt ◽  
Resting Cells ◽  
Moderately Halophilic ◽  
Moderately Halophilic Bacterium ◽  
Low Salt

The effect of sodium chloride on the respiratory activity of a moderately halophilic halotolerant bacterium was studied. Irrespective of growth conditions, resting cells oxidized succinate at a low rate unless sodium chloride was included in the assay mixture, maximum respiratory rates being obtained for sodium chloride concentrations between 0·2m and 0·8m. Neither potassium chloride nor sucrose could replace the sodium salt. The response of the respiratory system to sodium chloride concentration above the optimum depended on growth conditions. Respiration of cells harvested from a low-salt medium was almost inhibited completely by 2·0m-sodium chloride, and that of cells grown and washed in the presence of 2·0m-sodium chloride by 30%. After preincubation with a growth medium containing 2·0m-sodium chloride, even with all multiplication suppressed by chloramphenicol, the resistance of the respiratory system of low-salt-grown organisms to high salt concentrations increased considerably and resembled that of their high-salt-grown counterparts. A similar increase in resistance occurred after preincubation with yeast extract or with choline. With labelled choline, energy-dependent accumulation of labelled material occurred, the conditions required for maximum accumulation and retention being the same as those that increased the salt resistance of the respiratory system. The chromatographic behaviour of the labelled material indicated that the substance was not choline but a derivative, possibly betaine.

scholarly journals Characterization of Virus Adsorption by Using DEAE-Sepharose and Octyl-Sepharose

2002 ◽  
Vol 68 (8) ◽  
pp. 3965-3968 ◽  
Author(s):  
Patricia A. Shields ◽  
Samuel R. Farrah
Keyword(s):  
Sodium Chloride ◽  
Electrostatic Interactions ◽  
Hydrophobic Interactions ◽  
Chloride Concentration ◽  
Sodium Chloride Concentration ◽  
Virus Adsorption ◽  
Nacl Concentration

ABSTRACT Viruses were characterized by their adsorption to DEAE-Sepharose or by their elution from octyl-Sepharose by using buffered solutions of sodium chloride with different ionic strengths. Viruses whose adsorption to DEAE-Sepharose was reduced most rapidly by an increase in the sodium chloride concentration were considered to have the weakest electrostatic interactions with the solids; these viruses included MS2, E1, and φX174. Viruses whose adsorption to DEAE-Sepharose was reduced least rapidly were considered to have the strongest electrostatic interactions with the column; these viruses included P1, T4, T2, and E5. All of the viruses studied adsorbed to octyl-Sepharose in the presence of 4 M NaCl. Viruses that were eluted most rapidly following a decrease in the concentration of NaCl were considered to have the weakest hydrophobic interactions with the column; these viruses included φX174, CB4, and E1. Viruses that were eluted least rapidly from the columns after the NaCl concentration was decreased were considered to have the strongest hydrophobic interactions with the column; these viruses included f2, MS2, and E5.

scholarly journals Mitochondrial-reticular cytostructure in liver cells

1983 ◽  
Vol 214 (3) ◽  
pp. 795-813 ◽  
Author(s):  
J Katz ◽  
P A Wals ◽  
S Golden ◽  
L Raijman
Keyword(s):  
Endoplasmic Reticulum ◽  
High Speed ◽  
Citrate Synthase ◽  
Respiratory Control ◽  
High Salt ◽  
Marker Enzyme ◽  
Salt Medium ◽  
Low Speed ◽  
Low Salt ◽  
Specific Activities

This study examines the structural relationship of mitochondria and the endoplasmic reticulum in liver. Livers of rat and Japanese quail were homogenized and fractionated in media of 0.25 M-sucrose, either 5mM or 50 mM in sodium Hepes [4-(2-hydroxyethyl)-1-piperazine-ethanesulphonic acid], pH 7.4 (2.2 mM or 22 mM in Na respectively), designated here as low- and high-salt media. Three particulate fractions were prepared by sequential centrifugation. A nuclear pellet sedimenting at 300 g was obtained as described by Shore & Tata [(1977) J. Cell Biol. 72, 714-725], and from the resulting supernatant thereof a low-speed pellet (1100-1500 g) and a high-speed pellet (8000-10 000 g) were prepared. In the low-salt medium the yields of mitochondrial matrix enzymes (citrate synthase, glutamate dehydrogenase, ornithine carbamoyltransferase) and their specific activities in the low-speed pellet were over twice those in the high-speed pellet. In the high-salt medium the yield of matrix enzymes was 4-5 times, and the specific activities were up to 3 times, higher in the low-speed pellet than in the high-speed pellet. Oxygen uptake and respiratory control ratio were also much higher in the low-speed pellets in both media. Some 50-65% of the microsomal marker enzyme glucose 6-phosphatase was in the supernatant from the high-speed pellet, and the rest sedimented with the mitochondria. Repeated washing with the high-salt medium removes only a limited amount of reticulum. Washing with salt-free sucrose removes most of the reticulum, but a fraction remains strongly bound to mitochondria. Homogenates from quail and rat liver were fractioned isopycnically on Percoll gradients in either 0.25 M-sucrose or 0.25 M-sucrose/50 mM-sodium Hepes. Up to five particulate bands were separated and assayed. Mitochondria were present in two to three bands and were associated with endoplasmic reticulum. As seen in the phase-contrast microscope the mitochondria prepared in the low-salt medium consist of separate organelles. In the high-salt medium the mitochondria appear as chains of from three to ten organelles not touching each other. On addition of univalent ions at concentrations above 20 mM, the mitochondria aggregate into chains, and at higher ionic strength larger multidimensional aggregates are formed. The dispersion and aggregation of mitochondria are reversible. Negatively stained electron micrographs reveal a branched mitochondrial structure, with mitochondria held together by strands of reticulum.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals Plant Response to Saline Substrates II. Chloride, Sodium, and Potassium Uptake and Translocation in Young Plants of Hordeum Vulgare During and After a Short Sodium Chloride Treatment

1962 ◽  
Vol 15 (1) ◽  
pp. 39 ◽  
Author(s):  
H Greenway
Keyword(s):  
Sodium Chloride ◽  
Hordeum Vulgare ◽  
Salinity Stress ◽  
Chloride Concentration ◽  
Plant Response ◽  
Potassium Uptake ◽  
Sodium Chloride Concentration ◽  
Subsequent Response ◽  
Chloride Treatment ◽  
Sodium And Potassium

Young barley plants, Hordeum vulgare cv. Chevron, were subjected to a sodium chloride concentration of 100 m-equiv/l. In a "continued" treatment, the salinity stress was maintained for 15 days. In a "removed" treatment, sodium chloride was removed from the substrate after 5 days, and the subsequent response was studied over a period of 10 days.

Effect of sodium chloride concentration and temperature on melphalan stability during storage and use

1994 ◽  
Vol 51 (21) ◽  
pp. 2701-2704
Author(s):  
F. Pinguet ◽  
P. Martel ◽  
P. Rouanet ◽  
M. Fabbro ◽  
C. Astre
Keyword(s):  
Sodium Chloride ◽  
Chloride Concentration ◽  
Sodium Chloride Concentration

Studies on the Growth of Stichococcus Bacillaris Naeg in Culture

1974 ◽  
Vol 54 (2) ◽  
pp. 261-268 ◽  
Author(s):  
J. Hayward
Keyword(s):  
Sodium Chloride ◽  
High Salinity ◽  
Chloride Concentration ◽  
Sodium Chloride Concentration ◽  
Freshwater Organism ◽  
Ionic Concentrations ◽  
Morphogenetic Effects ◽  
Stichococcus Bacillaris

Stichococcus bacillaris has been grown under conditions of varying ionic concentrations. Sodium chloride appears to be the dominant compound in determining growth of this euryhaline alga and from the reaction to increased sodium chloride concentration it is postulated that S. bacillaris is a freshwater organism which can tolerate high salinities. Some morphogenetic effects of high salinity are described.

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