Sodium Acetate Medium Research Articles

赤痢菌の鑑別培地, CA培地について

We devised a Citrate-Acetate (CA) medium for rapidly differentiating Shigella. The medium consisted of 3.0 g of sodium citrate, 2.0 g of sodium acetate, 0.2 g of glucose, 1.0 g of dipotassium phosphate, 1.0 g of mono ammonium phosphate, 0.2 g of magnesium sulfate, 5.0 g of sodium chloride, 0.08 g of brom thymol blue, 15.0 g of agar, and 1000 ml of distilled water. An evaluation was made of the CA medium, for the rapid differentiation of 23 Shigella strains, 129 Escherichia coli strains and 130 isolates, that formed colourless colonies suspected to be Shigella on SS agar plate, from feces of healthy people. The results obtained were as follows 1) On the CA medium, all Shigella strains did not grow and there was no change in colour. 2) Positive growth rates of E. coli strains after incubation for 24 hr at 37 degrees C on CA medium, sodium acetate medium (Acet) and Christensen citrate medium (C-Cit) were 96.0%, 95.2% and 28.0%, respectively. Therefore, the positive growth rate of E. coli strains after incubation for 24 hr on CA medium was significantly higher (p less than 0.01) than that on C-Cit medium. 3) Positive growth rates of isolates after incubation for 24 hr at 37 degrees C on CA medium, Acet medium and C-Cit medium were 95.4%, 83.1% and 71.5%, respectively. Therefore, the positive growth rates of isolates after incubation for 24 hr on CA medium was significantly higher (p less than 0.01) than that on Acet medium and C-Cit medium.(ABSTRACT TRUNCATED AT 250 WORDS)

Monitoring of Sodium: Proton Exchange in Isolated Hepatocytes by Electronic Cell Sizing

To investigate volume-regulating processes in the hepatocyte, a rapid and precise method of measuring cell volume in isolated hepatocytes was devised which uses a Coulter Counter equipped with a Channelyzer. Isolated hepatocytes exhibit a volume-decreasing mechanism (potassium channel) which is triggered by cell volume increases as small as 10%. Cell volume increases in the hepatocyte may be mediated by activity of the Na:H exchanger. To examine Na:H exchange-mediated cell volume increases, without apparent interference by the volume-decreasing mechanism, acetate was substituted for chloride in the incubation medium. Hepatocytes placed in a medium containing sodium acetate at an acidic pH exhibit a continuous amiloride-sensitive swelling. A simple procedure was devised for estimating Na:H exchanger set-point by electronic cell sizing. In a sodium acetate medium, the internal pH equilibrates with the external pH. By placing cells in sodium acetate medium of various pH values and measuring the rate of amiloride-sensitive swelling, an estimate of Na:H exchanger set-point can be obtained. By this method, the exchanger was estimated to cease activity above an intracellular pH of 7.2. This method could be useful for identification of stimuli that might promote cell enlargement by raising the exchanger set-point. The phorbol ester 12-O-tetradecanoylphorbol-13-acetate tetraacetic acid raises the set-point of the exchanger in the isolated hepatocytes, resulting in exchanger activity at normal cellular pH, and at the same time promotes hepatocyte swelling. Exchanger activation via a kinase C-mediated mechanism is one possible way that hepatocyte enlargement may occur.

Electrolytic Generation of Cadmium(II) and Its Application to Coulometric Assays of Gallium and Indium

The current efficiency for the electrolytic generation of cadmium(II) from an amalgamated cadmium anode was investigated as a function of electrolyte composition and current density. The generation of cadmium(II) proceeded with 100% current efficiency over a wide range of current density, when both sodium chloride and sodium acetate concentrations were higher than 0.1M. Thus, the use of cadmium(II) instead of zinc(II) as a coulometric titrant for complexometry (T. Tanaka et al., Bunseki Kagaku, 33, E9 (1984)) reduced the error in amperometric indication of the end point. With 0.5M sodium chloride-0.5M sodium acetate medium of pH 5.5, high-purity gallium and indium were assayed coulometrically. The method was based on the reaction of the sample metal ion with a known excess of EDTA, the unconsumed EDTA being back-titrated with electrolytically generated cadmium(II). The relative standard deviation of the results was about 0.01% for both metals in the range of 200-300mg.

Spectrophotometric determination of some benzothiadiazine diuretics with 7,7,8,8-tetracyanoquinodimethane

A new spectrophotometric method for the determination of some benzothiadiazine drugs is presented, based on reaction with 7,7,8,8-tetracyanoquinodimethane in sodium acetate medium and measurement at 578 nm. Beer's law is obeyed in the concentration range 0.7–6.0 μg/ml for all eight drugs tested.

Sodium-hydrogen ion exchange in rabbit renal cortical slices incubated in acetate media.

1. Thin slices (0.2-0.3 mm) of rabbit renal cortex have been incubated in isosmotic oxygenated acetate media at 25 degrees C with or without ouabain (10(-3) M), amiloride (2 x 10(-3) M) or iodoacetamide (10(-3) M). 2. Slices in normal isosmotic 146 mM-sodium-132 mM-acetate media swelled as reported previously (Cooke & Macknight, 1984). This swelling was not prevented by amiloride or by metabolic inhibition. 3. Slices in isosmotic 132 mM-choline-132 mM-acetate media gained much less water and were little affected by ouabain, amiloride or metabolic inhibition. Choline was able to substitute neither for sodium nor for potassium in activating preparations of renal cortical Na+-K+-ATPase in chloride or in acetate media. 4. Slices in isosmotic 20 mM-sodium-132 mM-acetate medium swelled nearly as much as did slices in normal sodium acetate medium. However, this swelling was impaired markedly by amiloride, by ouabain and by metabolic inhibition. 5. There was a direct correlation between medium sodium concentration and slice water content as sodium was increased from 1.25 to 30 mM in 132 mM-acetate media. However, up to a sodium concentration of 10 mM, amiloride (2 x 10(-3) M) completely prevented this increase in water content. 6. Increasing medium amiloride concentration from 10(-5) to 10(-3) M progressively inhibited cellular swelling in 10 mM-sodium-132 mM-acetate medium. It is concluded that, under these experimental conditions, the dominant pathway for hydrogen ion extrusion from the cells was via amiloride-sensitive sodium-hydrogen exchange. 7. The results are discussed in terms of a model which explains cellular swelling in acetate media in terms of (a) non-ionic diffusion of acetic acid across plasma membranes impermeable to the acetate anion, (b) removal from the cells of the hydrogen ion gained with the acetate by amiloride-sensitive sodium-hydrogen counter-transport and (c) subsequent extrusion of sodium from the cell accompanied by potassium uptake via the ouabain-sensitive Na+-K+-ATPase. 8. The results provide evidence for ion movements across the luminal plasma membrane of proximal tubular cells in rabbit renal cortical slices.

Differential pulse polarographic determination of cephalexin based on the catalytic pre-wave of nickel(II)

A nickel-catalytic pre-peak at −0.72 V vs. Ag/AgCl, is caused by cephalexin in sodium acetate (pH 8.3) medium. It is used to determine 2.4 × 10 −7–6 × 10 −6 M cephalexin; the relative standard deviation is 4% for 0.88 μg ml −1 cephalexin. Other cephalosporins behave similarity; some amino acids can be tolerated in moderate amounts.

Spectrophotometric determination of trace amounts of aniline by diazotization coupling with N-(1-naphthyl)ethylenediamine and extraction

A spectrophotometric procedure is proposed for the determination of trace amounts of aniline by diazotization, coupling with N-(1-naphthyl)ethylenediamine in sodium acetate medium, extraction of the yellow dye with chloroform, and conversion into a reddish purple dye. Two methods are available for the conversion. In the first, the chloroform extract is shaken with hydrochloric acid and the dye is converted and transferred into the aqueous phase. In the other, the chloroform extract is evaporated to dryness and the residue is dissolved in glacial acetic acid. The hydrochloric acid extraction method is the more rapid. The minimum detection limits for the two methods are 0.8 and 0.6 μg/ml respectively. Both methods show satisfactory accuracy and precision.

Temporal accumulation of mannitol and arabitol in Geotrichum candidum.

The temporal depletion and accumulation of polyols were investigated in the fungus Geotrichum cnadidum. The major intracellular polyols were tentatively identified by paper chromatography as mannitol and arabitol. Inositol was also present in small quantities, and trehalose was also detected in appreciable concentrations. Germination and vegetative growth depended on the type and concentration of the sole exogenous carbon source. Mannitol occurred in arthrospores at 9.4% of the dry weight after several days growth in 2% (w/v) glucose solid medium, and became depleted during germination and vegetative growth in liquid medium containing 2% (w/v) glucose, 2% (w/v) sodium acetate or 25% (w/v) glucose as sole carbon source. This hexitol latter accumulated during arthrosporulation. The depletion and accumulation of ethanol-soluble carbohydrate believed to be primarily trehalose was temporally similar to that of mannitol. Arabitol accumulated intracellularly during germination and vegetative growth in sodium acetate medium and 25% glucose medium. This pentitol was not detected intracellularly at any culture age during growth in 2% glucose medium. Prolonged incubation of the culture in 25% glucose medium after stationary phase was reached resulted in the gradual disappearance of arabitol from the arthrospores simultaneously with an increase in intracellular mannitol. In comparison, ethanol-soluble carbohydrate did not change with prolonged incubation in this medium.

Specific and sensitive spectrophotometric determination of cobalt with 3-(2′-thiazolylazo)-2,6-diaminotoluene

Cobalt and 3-(2′-thiazolylazo)-2,6-diaminotoluene react in an acidic sodium acetate medium in the presence of vanadate to give several complexes. The soluble blue complex in a strong perchloric acid medium (H0=–0.5) obeys Beer's law between 0.05 and 0.60 p.p.m., with a molar absorptivity of 9.74 × 104 l mol–1 cm–1 at 590 nm, a Sandell sensitivity index of 0.60 ng cm–2 and a relative error of 0.13%. The method is highly specific and has been applied to the spectrophotometric determination of cobalt in low-alloy steels, hydrofining catalysts and high-purity nickel salts.

32P incorporation and growth of the hydrocarbon-degrading pseudomonad UP-2

The marine pseudomonad UP-2 grew, with a doubling time of 1.5 h at 30°C, in media supplemented withn-tetracosane as the sole organic carbon and energy source. Over 99% of the solid hydrocarbon was degraded. In order to overcome serious problems of sampling and measuring growth in the biphase system of hydrocarbon-water, a technique was developed combining the use of separate 1-ml eultures for each sample and32P labeling as an assay for growth. Using this technique, a growth durve of UP-2 onn-tetracosane was obtained. UP-2 pregrown on sodium acetate can utilize even-chain, liquid, or solidn-alkanes with no observable lag; in contrast, when UP-2 was pregrown onn-tetracosane and transferred to sodium acetate medium, a lag of 1 h was observed.

Induction of mitochondrial contraction and concomitant inhibition of succinate oxidation by magnesium ions

The addition of 1 Him MgCl 2 to partially swollen rat liver mitochondria respiring in an isoosmotic sucrose-sodium phosphate or sodium acetate medium containing 1 mm EDTA and 15 m m succinate (pH 7.2) initiates contraction, inhibits respiration, and alters the ultrastructural configuration of the inner membrane-cristae-matrix continuum. The maximal extent of contraction ( A 520 increase) attainable with MgCl 2 in the phosphate medium is about 80% of the maximal contraction induced by 2,4-dinitrophenol but exceeds the maximal contraction induced with ADP by about 10%. The extent of mitochondrial contraction and the inhibition of succinate oxidation are dependent on MgCl 2 concentration. MgCl 2 at 1000 μm immediately inhibits about 70% of the succinate oxidation and initiates maximal extent of contraction concomitant with a distinct configurational change in ultrastructure which appears to differ from that initiated by either ADP or dinitrophenol. MgCl 2 at 150 μm does not inhibit the rate of succinate oxidation but it does initiate about 75% of the maximal contraction ( A 520 increase) attained with 1000 μ m MgCl 2. The rate of mitochondrial contraction is dependent on both the phosphate and MgCl 2 concentration. CaCl 2, in contrast to MgCl 2, immediately stimulates succinate oxidation and after a sharp contraction spike of short duration initiates additional expansion of the inner membrane-cristae-matrix continuum. The contraction spike occurs in a reaction system containing either phosphate or acetate. The results are consistent with the notion that Mg 2+ and Ca 2+ may modulate mitochondrial volume and exert control over certain oxidative processes.

Creatine Kinase of Rat Heart Mitochondria: COUPLING OF CREATINE PHOSPHORYLATION TO ELECTRON TRANSPORT

Abstract Intact mitochondria from human, beef, and rat heart, as well as rat brain and rat skeletal and smooth muscle, contain considerable creatine kinase activity; those from rat or rabbit liver, kidney, and testis contain essentially none. In rat heart mitochondria creatine kinase activity is far higher than the activity of adenylate kinase and nucleoside diphosphokinase. The heart mitochondrial creatine kinase is specific for ATP and ADP as phosphate donor and acceptor. The optimum pH is 6.7 in the direction of ATP formation and 8.0 in the direction of phosphocreatine formation. The mitochondrial isoenzyme of creatine kinase is not present in the same compartment as the intermembrane marker enzyme adenylate kinase, but may be released in soluble form by exposure to sodium acetate or sodium phosphate medium at pH 7.4. The phosphorylation of creatine by intact mitochondria takes place outside the atractyloside-sensitive ADP-ATP carrier system of the inner membrane and thus requires external ATP. When creatine in the concentration range known to be present in intact heart is added to rat heart mitochondria neither the initial State 4 or State 3 rate of respiration (succinate) is affected; however, there is a large increase in the State 4 rate following addition of ADP, whose magnitude increases as the creatine concentration is increased. In the presence of physiological concentrations of creatine and ADP rat heart mitochondria respire at a constant high rate equal to 75 to 85% of their maximal State 3 rate; under these conditions phosphocreatine is the end product of oxidative phosphorylation. The Km values for rat heart mitochondria are 35 µm for ADP, 0.72 mm for phosphocreatine, 100 µm for ATP, and 6 mm for creatine. These and other properties suggest that in addition to the ∼P storage function usually postulated for it, the phosphocreatine-creatine kinase system serves to smooth out or buffer the rate of respiration of heart mitochondria at a high and constant rate, as well as to channel ∼P to the contractile system via the mitochondrial and sarcoplasmic isoenzymes of creatine kinase.

Light-induced structural transitions of chloroplasts studied by the spin-probe method.

The light‐induced structural state changes of chloroplast (swelling and shrinkage) are compared with the change of activity (ferrcyanide reduction and photophosphorylation) and the state of hydrophobic membrane parts, characterised by the electron spin resonance spectra of iminoxyl radical‐probe, introduced in the membrane.Shrinkage of chloroplasts in sodium acetate medium is accompanied by non‐essential changes of activity and conformational state. Moreover light‐induced swelling in sodium chloride medium is accompanied by transition of chloroplasts to the uncoupled state and by change of conformational state.The regulatory function of conformational transitions in the chloroplasts is discussed and the corresponding scheme of regulation of photophosphorylation is suggested.

The mechanism of mitochondrial swelling. VIII. Permeability of mitochondria to alkali metal acetates

The capacity of beef heart mitochondria to undergo osmotically induced volume changes in decimolar M+-acetate or other weak acid anion media is characterized by the following features: (1) mitochondria resist swelling when suspended in potassium or rubidium acetate media in the presence of respiratory inhibitors; (2) mitochondria swell extensively when suspended in ammonium or sodium acetate media in the presence of respiratory inhibitors; and (3) actively respiring mitochondria swell extensively whether suspended in ammonium, sodium, potassium, or rubidium acetate media. These findings have been interpreted to mean that (1) the nonenergized mitochondrial inner membrane is permeable to acetate anions, (2) the nonenergized mitochondrial inner membrane is permeable to ammonium and sodium ions in the presence of acetate or other weak acid anions, (3) the nonenergized mitochondrial inner membrane is relatively impermeable to potassium and rubidium ions in the presence of acetate or other weak acid anions, and (4) energized mitochondria are considerably more permeable to potassium and rubidium (acetate) ions than are non-energized mitochondria. The experiments described in this communication which provide the evidence for these interpretations involve methods which are independent of volume changes. The results confirm the first three of the above interpretations but are inconsistent with the fourth. A general theory for passive ion movements in mitochondria is presented and the results are discussed in terms of the development of an energy dependent ion gradient as the key to energized swelling in potassium or rubidium acetate.

On the influence of thiamine and ammonium ions on alcoholic fermentation

1. 1. In a glucose-sodium acetate medium of pH 5.6 the fermentation rate of bakers' yeast remains constant at a low level during several hours, while in the presence of ammonium sulphate it gradually increases. The rise is steeper in the presence of thiamine. 2. 2. After the ammonium ions have been utilized the rate of fermentation decreases to a level, the height of which depends upon the amounts of ammonium sulphate and thiamine added. 3. 3. In the presence of an ammonium salt not containing assimilable sulphur in its anion a decrease of the fermentation rate occurs before the ammonium ions have been utilized. This decrease is not observed when besides the ammonium salt a suitable amount of sodium sulphate is added. 4. 4. Thiamine and ammonium sulphate exert their effect on fermentation in a sodium acetate medium of pH 5.6, and under these conditions also considerable amounts of protein and carboxylase are formed. When the same buffer salt is used at pH 3.5 the effects of both thiamine and ammonium sulphate on the fermentation rate are absent, and no protein and carboxylase are formed either. In the presence of K 2SO 4, KH 2PO 4, Na 2SO 4 or NaH 2PO 4, however, the effects of both thiamine and ammonium sulphate on the fermentation rate are also observed at this pH, while under these conditions the synthesis of carboxylase, and consequently the synthesis of protein, also occurs again. 5. 5. An explanation of the phenomena observed in glucose-sodium acetate medium of pH 5.6 containing ammonium sulphate is given. 6. 6. In a glucose-sodium acetate medium of pH 5.6 containing ammonium sulphate and thiamine the maximal amount of carboxylase is formed with concentrations of ammonium sulphate of 0.01 to 0.02% and higher, and amounts of 0.02 to 0.05 μg thiamine per 2 mg yeast, after 2 to 4 hours' fermentation. These data correspond closely to those concerning the effects of thiamine and ammonium sulphate on the fermentation rate. 7. 7. After 6 hours' fermentation in the presence of excess ammonium sulphate (0.1%)—thiamine being absent—the rate of fermentation, the amount of protein, and the amount of carboxylase all appeared to have increased by about 50%, while the number of cells had only increased by about 30% as compared to the control experiment (glucose-sodium acetate). 8. 8. After 6 hours' fermentation in the presence of an excess of both ammonium sulphate and thiamine the rate of fermentation and the amout of carboxylase had once more increased by about 60%, and the number of cells by about 20%, whereas the amount of protein had not more increased than in the presence of ammonium sulphate alone. 9. 9. The effect of thiamine upon the fermentation of bakers' yeast depends quantitatively upon the formation of carboxylase, this enzyme being the limiting factor of fermentation, both in the absence and in the presence of ammonium sulphate. 10. 10. Like bakers' yeast, brewers' yeast also forms carboxylase in the presence of ammonium sulphate. The addition of thiamine to the medium, however, has no influence on the amount of carboxylase formed. The amount of non-carboxylase thiamine pyrophosphate present in the brewers' yeast obviously is sufficient for obtaining the maximal content of carboxylase. This explains why the fermentation of brewers' yeast is not influenced by added thiamine.