The effect of ethylenediaminetetraacetate and its calcium chelate on the rate of swelling of a strain of Pseudomonas aeruginosa in salt solutions

1972 ◽  
Vol 18 (11) ◽  
pp. 1643-1646
Author(s):  
Frederick Bernheim
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Carboxylic Acids ◽  
Salt Solutions ◽  
Electrostatic Forces ◽  
Anionic Sites ◽  
Barium Strontium ◽  
Sites Of Action

When washed suspensions of Pseudomonas aeruginosa are placed in salt solutions, the cells shrink rapidly and then swell more slowly as salt and water enter them. The rate of swelling is increased by EDTA and its calcium chelate. The effect of EDTA is antagonized by diamines; the effect of the calcium chelate by carboxylic acids. The relative effects of EDTA and the calcium chelate differ in different salts which suggests different sites of action. The evidence indicates that EDTA does not act by chelating calcium or magnesium in the membrane of these cells but that its two nitrogen atoms combine by electrostatic forces with anionic sites, and the chelate, in which the nitrogen atoms are bound to calcium, combines by the same forces to cationic sites. Barium, strontium, and magnesium chelates are inactive.

The Dissociation Constants of Acids in Salt Solutions. VI. Carbocyclic Carboxylic Acids

1953 ◽  
Vol 75 (8) ◽  
pp. 1854-1856 ◽  
Author(s):  
Martin Kilpatrick ◽  
Jerome G. Morse
Keyword(s):  
Carboxylic Acids ◽  
Dissociation Constants ◽  
Salt Solutions

Effect of medium on dissociation of carboxylic acids

1985 ◽  
Vol 50 (12) ◽  
pp. 2670-2678 ◽  
Author(s):  
Jiří Mollin ◽  
Zdeněk Pavelek ◽  
Jitka Navrátilová ◽  
Alena Recmanová
Keyword(s):  
Benzoic Acid ◽  
Organic Solvent ◽  
Carboxylic Acids ◽  
Ion Transfer ◽  
Electrostatic Forces ◽  
Two Component ◽  
Born Equation

pK Values of carboxylic acids have been measured in mixtures water-organic solvent and confronted with the Born equation. Solubilities of benzoic acid have been measured. From the pK and solubilities found the ΔGt0(C6H5COO-) values have been calculated for various two-component solvents. The results agree with the idea that the ion transfer into another medium is affected not only by electrostatic, but also by non-electrostatic forces.

The Dissociation Constants of Acids in Salt Solutions. V. Monohydroxycyclohexane-carboxylic Acids

1953 ◽  
Vol 75 (8) ◽  
pp. 1846-1853 ◽  
Author(s):  
Martin Kilpatrick ◽  
Jerome G. Morse
Keyword(s):  
Carboxylic Acids ◽  
Dissociation Constants ◽  
Salt Solutions

The effect of streptomycin on cell size of a strain of Pseudomonas aeruginosa

1969 ◽  
Vol 15 (2) ◽  
pp. 209-213
Author(s):  
Frederick Bernheim
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Cell Size ◽  
Salt Solution ◽  
Ammonia Assimilation ◽  
Salt Solutions

Washed cells of a strain of Pseudomonas aeruginosa rapidly decrease in size when they are put in salt solutions and then upon incubation increase in size. In the presence of streptomycin (10 μg/ml) this increase is followed by a decrease but only if ammonia has been assimilated by the cells in the presence of an oxidizable substrate. The extent of the decrease caused by streptomycin is proportional to the amount of ammonia assimilated and also the concentration of the salt solution. Chlortetracycline (0.02 μg/ml), chloramphenicol (1.0 μg/ml), and cycloserine (10 μg/ml) completely inhibit the streptomycin effect when added before or after ammonia assimilation is complete.

scholarly journals Exploring the chemical space of ureidothiophene-2-carboxylic acids as inhibitors of the quorum sensing enzyme PqsD from Pseudomonas aeruginosa

2015 ◽  
Vol 96 ◽  
pp. 14-21 ◽  
Author(s):  
J. Henning Sahner ◽  
Martin Empting ◽  
Ahmed Kamal ◽  
Elisabeth Weidel ◽  
Matthias Groh ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Quorum Sensing ◽  
Carboxylic Acids ◽  
Chemical Space

A cleft type receptor which combines an oxyanion hole with electrostatic interactions

2017 ◽  
Vol 15 (21) ◽  
pp. 4571-4578 ◽  
Author(s):  
Omayra H. Rubio ◽  
Sara del Mazo ◽  
Laura M. Monleón ◽  
Luis Simón ◽  
Álvaro G. Temprano ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Electrostatic Interactions ◽  
X Ray Diffraction ◽  
Electrostatic Forces ◽  
Oxyanion Hole ◽  
X Ray ◽  
Type Receptor ◽  
Hole Structure

The association of carboxylic acids with a receptor which combines an oxyanion hole structure with electrostatic forces has been studied by X-ray diffraction, finding different arrangements for the H-bond pattern.

scholarly journals The behavior of ions in water is controlled by their water affinity

2019 ◽  
Vol 52 ◽  
Author(s):  
Kim D. Collins
Keyword(s):  
Long Range ◽  
Short Range ◽  
Ion Pairs ◽  
Size Exclusion ◽  
Water Molecules ◽  
Dielectric Relaxation Spectroscopy ◽  
Salt Solutions ◽  
Electrostatic Forces ◽  
Aqueous Salt Solutions ◽  
Water Affinity

Abstract The strong, long-range electrostatic forces described by Coulomb's law disappear for ions in water, and the behavior of these ions is instead controlled by their water affinity – a weak, short-range force which arises from their charge density. This was established experimentally in the mid-1980s by size-exclusion chromatography on carefully calibrated Sephadex® G-10 (which measures the effective volume and thus the water affinity of an ion) and by neutron diffraction with isotopic substitution (which measures the density and orientation of water molecules near the diffracting ion and thus its water affinity). These conclusions have been confirmed more recently by molecular dynamics simulations, which explicitly model each individual water molecule. This surprising change in force regime occurs because the oppositely charged ions in aqueous salt solutions exist functionally as ion pairs (separated by 0, 1 or 2 water molecules) as has now been shown by dielectric relaxation spectroscopy; this cancels out the strong long-range electrostatic forces and allows the weak, short-range water affinity effects to come to the fore. This microscopic structure of aqueous salt solutions is not captured by models utilizing a macroscopic dielectric constant. Additionally, the Law of Matching Water Affinity, first described in 1997 and 2004, establishes that contact ion pair formation is controlled by water affinity and is a major determinant of the solubility of charged species since only a net neutral species can change phases.

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