Verification of the approximate equitransference of the aqueous potassium chloride salt bridge at high concentrations

1990 ◽  
Vol 62 (10) ◽  
pp. 1019-1021 ◽  
Author(s):  
Paolo. Longhi ◽  
Fernando. D'Andrea ◽  
Patrizia R. Mussini ◽  
Torquato. Mussini ◽  
Sandra. Rondinini
Keyword(s):  
Potassium Chloride ◽  
Salt Bridge ◽  
Chloride Salt ◽  
High Concentrations

Equitransferent Salt Bridge for Elimination of the Diffusion Potential Compared with a Saturated Potassium Chloride Salt Bridge.

1951 ◽  
Vol 5 ◽  
pp. 422-430 ◽  
Author(s):  
K. V. Grove-Rasmussen ◽  
C.-B. Laurell ◽  
Henrik Dam ◽  
Jörgine Stene Sörensen ◽  
Nils Andreas Sörensen
Keyword(s):  
Potassium Chloride ◽  
Salt Bridge ◽  
Diffusion Potential ◽  
Chloride Salt

EFFECTS OF SODIUM AND POTASSIUM CHLORIDE ON CERTAIN ENZYMES OF MICROCOCCUS HALODENITRIFICANS AND PSEUDOMONAS SALINARIA

1956 ◽  
Vol 2 (6) ◽  
pp. 599-606 ◽  
Author(s):  
R. M. Baxter ◽  
N. E. Gibbons
Keyword(s):  
Potassium Chloride ◽  
Cytochrome Oxidase ◽  
Salt Content ◽  
Lactic Dehydrogenase ◽  
Extreme Halophile ◽  
Optimal Conditions ◽  
Moderate Halophile ◽  
Extreme Halophiles ◽  
High Concentrations ◽  
Sodium And Potassium

The isocitric, succinic, malic, and lactic dehydrogenases and cytochrome oxidase from Pseudomonas salinaria, an extreme halophile, are most active in high concentrations of sodium or potassium chloride. The lactic dehydrogenase and cytochrome oxidase of Micrococcus halodenitrificans are also more active at high concentrations of salt, but the isocitric, succinic, malic, α-ketoglutaric, and glutamic dehydrogenases of this moderate halophile are most active at much lower concentrations. It is concluded that the extreme halophiles have a high intracellular salt content. It is suggested that M. halodenitrificans maintains an intracellular salt concentration of about 0.5 M under optimal conditions for growth and that cytochrome oxidase is important in maintaining this level against a concentration gradient.

Corrosion of carbon steel underneath a lead/potassium chloride salt mixture

2019 ◽  
Vol 70 (8) ◽  
pp. 1450-1460 ◽  
Author(s):  
Annika Talus ◽  
Hanna Kinnunen ◽  
Rikard Norling ◽  
Sonja Enestam
Keyword(s):  
Carbon Steel ◽  
Potassium Chloride ◽  
Chloride Salt ◽  
Salt Mixture

Calculation and Optimization of Molten Salt for Solar High Temperature Heat Storage

2012 ◽  
Vol 178-181 ◽  
pp. 62-65
Author(s):  
Qiu Hui Yan ◽  
Hong Na Wang
Keyword(s):  
Heat Transfer ◽  
High Temperature ◽  
Energy Storage ◽  
Sodium Chloride ◽  
Potassium Chloride ◽  
Heat Storage ◽  
Chloride Salt ◽  
Salt Mixtures ◽  
Temperature Heat ◽  
Carbonate Salt

The development of energy saving technologies is very actual issue of present day. One of perspective directions in developing these technologies is the thermal energy storage in various industry branches. To meet the requirement of high temperature of solar heat transfer and thermal storage, this paper calculated several sets of data for lots of pure salts and salt mixtures. The results show that, comparing with the ternary carbonate salt (potassium carbonate (0.7) - sodium carbonate (0.1) -potassium chloride (or sodium chloride)), the ternary chloride salt (potassium chloride (0.037) - calcium chloride (0.5) - sodium chloride) is more perspective.

Ratcheting between Two Distinct Conformations of Substrate Drives the Sequential Cleavage of Prothrombin by Prothrombinase.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 1717-1717
Author(s):  
Elsa Bianchini ◽  
Steven J. Orcutt ◽  
Sriram Krishnaswamy
Keyword(s):  
Conformational Change ◽  
Conformational Changes ◽  
Conformational Transition ◽  
Salt Bridge ◽  
Single Type ◽  
Thrombin Inhibitor ◽  
Short Delay ◽  
Bridge Formation ◽  
Initial Cleavage ◽  
High Concentrations

Abstract The conversion of human prothrombin to thrombin requires the cleavage of two peptide bonds. When catalyzed by prothrombinase, the reaction proceeds almost exclusively via initial cleavage at R320 followed by cleavage at R271 yielding meizothrombin (mIIa) as an intermediate. The scissile bonds are expected to be ~36 A apart in the zymogen. Yet, remarkably, evidence indicates that cleavage at these two sites is accomplished by a single type of exosite interaction that tethers the substrate to prothrombinase. The ability of prothrombinase to act on these spatially distinct sites, with such constraints, can be explained by a conformational change in the substrate following initial cleavage at R320. Cleavage at this site leads to internal salt bridge formation and a conformational transition to the proteinase. The role of the zymogen to proteinase transition in substrate cleavage was investigated by the use of a fully-carboxylated recombinant prothrombin derivative (IITAT) with the I-V-E sequence following R320 replaced with T-A-T. Thrombin produced by cleavage of IITAT exhibited ~0.2% of the catalytic activity observed with thrombin produced from wild type recombinant prothrombin (IIWT). IITAT can be cleaved at the R320 site but fails to undergo all subsequent conformational changes required for proteinase formation. SDS-PAGE and quantitative densitometry revealed that the action of prothrombinase on either IIWT or IITAT was consistent with ordered cleavage at R320 followed by cleavage at R271. The rates of consumption of IIWT and IITAT resulting from cleavage at R320 were equivalent. Cleavage at R320 in IITAT by prothrombinase is not detectably affected by the substituted P1′-P3′ sequence. The disappearance of IIWT was accompanied by a transient accumulation in mIIa that decreased to zero within 4 minutes while thrombin accumulated following a short delay. With IITAT, mIIa accumulated to higher levels and persisted for 45 minutes. Thrombin was produced with a lower rate and a longer delay phase. The findings imply a substantial decrease in the rate of the second cleavage reaction at R271 resulting from distant effects of the new P1′-P3′ residues following R320. The thrombin inhibitor, dansylarginine-N-(3-ethyl-1,5-pentanediyl)amide (DAPA) had no effect on the cleavage reactions in IIWT. However, increasing concentrations of DAPA as high as 400 μM were found to systematically enhance the rate of thrombin formation from IITAT by correcting defective cleavage at R271. The data are consistent with the interpretation that IITAT can be cleaved normally at R320 but subsequent accessibility and cleavage at R271 is reduced because of a defect in internal salt bridge formation and the conformational change associated with proteinase formation. Rescue of this defect by high concentrations of DAPA likely relates to the stabilization of a proteinase-like conformation in the intermediate produced by cleavage of IITAT at R320. Our findings suggest an important role for the zymogen to proteinase transition in determining the sequential action of prothrombinase on the two sites in prothrombin. We propose that exosite-dependent tethering of two distinct conformations of the substrate to prothrombinase drives the presentation of distantly positioned cleavage sites to the active site of the enzyme and accounts for the sequential cleavage of prothrombin.

Sign in / Sign up

Export Citation Format

Share Document