THE EFFECT OF MAGNESIUM, POTASSIUM, AND IRON ON THE GROWTH AND MORPHOLOGY OF RED HALOPHILIG BACTERIA

1955 ◽  
Vol 1 (7) ◽  
pp. 486-494 ◽  
Author(s):  
Helen J. Brown ◽  
N. E. Gibbons
Keyword(s):  
Sodium Chloride ◽  
Halophilic Bacteria ◽  
Maximum Growth ◽  
Potassium Ion ◽  
Ferrous Ion ◽  
Magnesium Ion ◽  
Ammonium Ions ◽  
Coccoid Form ◽  
Low Concentrations

Maximum growth of the red halophilic bacteria occurs in the presence of 3.0 to 5.0 M sodium chloride, 0.1 to 0.5 M magnesium ion, 50 to 100 p.p.m. (1.3 to 2.5 × 10−3 M) potassium ion, and 0.5 to 1.0 p.p.m. (1 to 2 × 10−5 M) ferrous ion. In magnesium deficient media the rod forms become coccoid. Some strains can be adapted to grow in low concentrations of magnesium (0.01 M) and these adapted strains retain a coccoid form even when transferred to higher concentrations of magnesium. Growth does not occur when potassium is removed from the medium. The potassium requirement may be satisfied by rubidium but not by cesium, lithium, or ammonium ions. Potassium partially replaces the sodium chloride requirement of the red halophiles.

TURBIDITY OF SUSPENSIONS AND MORPHOLOGY OF RED HALOPHILIC BACTERIA AS INFLUENCED BY SODIUM CHLORIDE CONCENTRATION

1960 ◽  
Vol 6 (5) ◽  
pp. 535-543 ◽  
Author(s):  
Dinah Abram ◽  
N. E. Gibbons
Keyword(s):  
Sodium Chloride ◽  
Salt Concentration ◽  
Morphological Changes ◽  
Halophilic Bacteria ◽  
Chloride Concentration ◽  
Chloride Content ◽  
Wall Structure ◽  
Abrupt Decrease ◽  
High Sodium ◽  
Rigid Cell Wall

The optical densities of suspensions of cells of Halobacterium cutirubrum, H. halobium, or H. salinarium, grown in media containing 4.5 M sodium chloride, increase as the salt concentration of the suspending medium decreases, until a maximum is reached at about 2 M; below this concentration there is an abrupt decrease in optical density. The cells are rod shaped in 4.5 M salt and change, as the salt concentration decreases, through irregular transition forms to spheres; equal numbers of transition forms and spheres are present at the point of maximum turbidity, while spheres predominate at lower salt concentrations. Cells suspended in 3.0 M salt, although slightly swollen, are viable, but viability decreases rapidly with the more drastic changes in morphology at lower salt concentrations. Cells grown in the presence of iron are more resistant to morphological changes but follow the same sequence. Cells "fixed" with formaldehyde, at any point in the sequence, act as osmometers and do not rupture in distilled water although their volume increases 10–14 times. The results indicate that the red halophilic rods require a high sodium chloride content in their growth or suspending medium to maintain a rigid cell wall structure.

Study of Red Halophilic Bacteria in Solar Salt and Salted Fish: II. Bacto-oxgall as a Selective Agent for Differentiation

1956 ◽  
Vol 13 (2) ◽  
pp. 195-199 ◽  
Author(s):  
H. P. Dussault
Keyword(s):  
Halophilic Bacteria ◽  
Partial Identification ◽  
Selective Medium ◽  
Selective Agent ◽  
Simple Method ◽  
Solar Salt ◽  
Salted Fish ◽  
Low Concentrations ◽  
Fish Samples

A simple method, based on oxgall tolerance, is proposed for differentiating red halophilic bacteria commonly found in solar salt and discoloured salted codfish. Tests carried out on 18 strains isolated from various sources have shown that the rod forms are inhibited by low concentrations of Bacto-oxgall and that the coccus forms tolerate relatively high ones. Bacto-oxgall can thus be used as the basis of a simple selective medium. This test has been found useful for the isolation, purification and partial identification of unidentified strains and also for determining the relative proportions of the two main types of red halophilic bacteria present in solar salt and salted fish samples.

Zinc nutrition and salt preference in rats

1981 ◽  
Vol 241 (3) ◽  
pp. R233-R239 ◽  
Author(s):  
W. Jakinovich ◽  
D. W. Osborn
Keyword(s):  
Sodium Chloride ◽  
Zinc Deficiency ◽  
Clinical Symptoms ◽  
Taste Receptor ◽  
Maximum Growth ◽  
Central Nervous System Disorder ◽  
Receptor Sensitivity ◽  
Electrophysiological Responses ◽  
Zinc Nutrition ◽  
System Disorder

Zinc-deficient rats have an increased preference for sodium chloride (saltwater). We investigated the possibility that this elevated saltwater preference is due to nonfunctional taste receptors. In experiment I, zinc-deficient rats consumed more saltwater than zinc-sufficient rats at most sodium chloride concentrations tested (0.001-1.0 M). When the zinc-deficient rats were fed a zinc-sufficient diet, the clinical symptoms of zinc deficiency rapidly disappeared. However, the rats still preferred saltwater to a greater extent than rats maintained on the zinc-sufficient diet. In experiment II, rats fed diets supplemented with levels of zinc below the requirement for maximum growth had an increased preference for saltwater (0.15 M NaCl). In experiment III, electrophysiological responses of the taste nerves to various concentrations of sodium chloride, sucrose, quinine . HCl, and hydrochloric acid were the same in both zinc-deficient and zinc-sufficient rats. We conclude that the taste receptor sensitivity of the rat is not impaired by zinc deficiency. The increased salt preference of zinc-deficient rats might be related to some endocrine or central nervous system disorder precipitated by inadequate dietary zinc.

Disinfection potential of electrolyzed solutions containing sodium chloride at low concentrations

2000 ◽  
Vol 85 (1-2) ◽  
pp. 163-174 ◽  
Author(s):  
Chizuko Morita ◽  
Kouichi Sano ◽  
Shinichi Morimatsu ◽  
Hiromasa Kiura ◽  
Toshiyuki Goto ◽  
...  
Keyword(s):  
Sodium Chloride ◽  
Low Concentrations

Response of plants to calcium concentration in solution culture

1968 ◽  
Vol 19 (6) ◽  
pp. 845 ◽  
Author(s):  
JF Loneragan ◽  
K Snowball ◽  
WJ Simmons
Keyword(s):  
Maximum Growth ◽  
Calcium Deficiency ◽  
Solution Culture ◽  
Growth Stages ◽  
Culture Techniques ◽  
Deficiency Symptoms ◽  
Nutrient Culture ◽  
Low Concentrations ◽  
Severe Deficiency ◽  
Wide Range

Calcium concentrations required in solution for growth of 30 grasses, cereals, legumes, and herbs were defined for a wide range of concentrations which were maintained constant in Bowing culture solutions of pH 5.7. Contrary to published results obtained with standard nutrient culture techniques, some legumes and herbs grew much better at low concentrations of calcium (2.5 and 10µM ) than many Gramineae. The minimal concentration required to produce maximum growth of plants and eliminate calcium deficiency symptoms varied widely (2.5–1000 µM) within each group; it varied over the same range for Gramineae as for legumes and herbs. At 100 µM all plants grew well without symptoms of calcium deficiency. Increasing the concentration to 1000 µM increased growth in only a few species. At concentrations < l µM , severe deficiency symptoms developed on the tops of all species. The growth of legumes and herbs was more quickly and more severely affected than that of Gramineae. The roots of many legumes and herbs also degenerated rapidly. In the same solutions the roots of all Gramineae appeared healthy for some time. However, the advantage of Gramineae in these solutions was transitory, since the high relative growth rate in their early growth stages fell rapidly. It is suggested that distinct processes dominate the plants' behaviour at each range of calcium concentrations. At extremely low concentrations (< l µM ) , to which legumes and herbs are more sensitive than Gramineae, the dominant process may involve ion exchange equilibria between calcium in the environment and in the cell walls or membranes. At higher concentrations (2.5–1000 µM), to which Gramineae are as sensitive as legumes and herbs, processes of absorption of calcium from solution and translocation to plant tops are probably dominant.

scholarly journals Glutamate, calcium ion-chelating agents and the sodium and potassium ion contents of tissues from the brain

1970 ◽  
Vol 116 (2) ◽  
pp. 181-187 ◽  
Author(s):  
I. Pull ◽  
H. McIlwain ◽  
R. L. Ramsay
Keyword(s):  
Calcium Ion ◽  
Chelating Agents ◽  
Potassium Ion ◽  
Low Concentrations ◽  
Rate Of Increase ◽  
Other Substances ◽  
Ion Contents ◽  
Bicarbonate Solutions ◽  
The Brain ◽  
Sodium And Potassium

1. Salts of l-glutamate added to cerebral tissues maintained in glucose–saline–bicarbonate solutions cause the Na+ content of the tissues to increase rapidly and K+ to be lost. Entry of 22Na+ also is accelerated by l-glutamate and this acceleration is inhibited by low concentrations of tetrodotoxin. 2. Tissue Na+ content and its rate of increase after the addition of l-glutamate are affected by the Ca2+ of incubation media. 3. Very rapid and extensive entry of Na+ to the tissue is caused by EDTA, and a moderate entry by citrate and ATP. Calculations of the concentration of free Ca2+ in media after these additions indicate that Na+ entry is sometimes associated with low Ca2+ concentration, but that other substances, especially l-glutamate, act without greatly diminishing Ca2+ concentration. 4. Experiments with 2,4-dinitrophenol and valinomycin are also reported and aspects of the Na+ entry formulated and discussed.

scholarly journals Re-activation of the peptidyltransferase centre of rabbit reticulocyte ribosomes after inactivation by exposure to low concentrations of magnesium ion

1976 ◽  
Vol 160 (3) ◽  
pp. 521-531 ◽  
Author(s):  
R A Cox ◽  
P Greenwell ◽  
W Hirst
Keyword(s):  
Conformational Change ◽  
Gel Electrophoresis ◽  
Supernatant Fraction ◽  
Magnesium Ion ◽  
Differential Centrifugation ◽  
Base Pairs ◽  
Low Concentrations ◽  
Mgcl2 Concentration ◽  
Protein Moiety ◽  
Rabbit Reticulocytes

1. The larger subrivosomal particles of rabbit reticulocytes retained full activity in the puromycin reaction and in poly(U)-directed polyphenylalanine synthesis after 4h at 0° C when buffered 0.5M-NH4Cl/10-30mM-MgCl2 was the solvent. 2. Activity in the puromycin reaction was diminished to approx 10% after 15-30 min at 0° C when the concentration of MgCl2 was lowered to 2mM. 3. Activity was not restored when the concentration of MgCl2 was raised from 2mM to 10-30 mM at 0° C. However, activity was recovered as measured by both assay systems when the ribosome fraction was heated to 37° C at the higher concentrations of MgCl2. 4. Recovery of activity was noted during the course of the polyphenylalanine synthesis in 50 mM-KCl/5mM-MgCl2/25mM-Tris/HCl, pH 7.6, at 37° C. Re-activation was slow at 20° C and below. 5. No more than about 5% of the protein moiety of the subparticle was lost in 0.5M-NH4Cl on decreasing MgCl2 concentration from 10mM to 2mM. No proteins were detected in the supernatant fractions by gel electrophoresis after ribosomes were separated by differential centrifugation. The supernatant fraction was not essential for the recovery of activity. However, at higher (e.g. 1M) concentrations of NH4Cl, proteins were split from the subparticle. 6. The loss and regain of activity found on lowering and restoring the concentration of MgCl2 at 0.5M-NH4Cl appears to arise from a conformational change that does not seem to be associated with a loss and regain of particular proteins. 7. A 2% decrease in E260 was noticed when the concentration of Mg2+ was restored, and the change in the spectrum indicated a net increase of approx. 100A-U base-pairs per subribosomal particle. 8. When the concentration of Mg2+ was restored, s20,w of the subparticle remained at 52± 1S until the sample was incubated at 37° C when s20,w increased to 56 ± 1S compared with the value of 58 ± 1S for the subparticle as originally isolated.

Investigation of an electrodeionization system for the removal of low concentrations of ammonium ions

Desalination ◽  
1999 ◽  
Vol 123 (1) ◽  
pp. 85-92 ◽  
Author(s):  
E.F. Spiegel ◽  
P.M. Thompson ◽  
D.J. Helden ◽  
H.V. Doan ◽  
D.J. Gaspar ◽  
...  
Keyword(s):  
Ammonium Ions ◽  
Low Concentrations
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