Interactions between large organic ions of opposite charge. II. The effect of ionic strength, temperature, and urea on the interaction between sodium dodecyl sulfate and benzyltriphenylphosphonium chloride

1976 ◽  
Vol 56 (2) ◽  
pp. 350-359 ◽  
Author(s):  
G.I Mukhayer ◽  
S.S Davis
Keyword(s):  
Ionic Strength ◽  
Sodium Dodecyl Sulfate ◽  
Sodium Dodecyl ◽  
Opposite Charge ◽  
Organic Ions ◽  
Dodecyl Sulfate

Influence of Anionic Surfactants and Ionic Strength on α-Coymotrypsin-Catalyzed Reactions

1972 ◽  
Vol 50 (4) ◽  
pp. 392-398 ◽  
Author(s):  
J. E. Gaudin ◽  
T. Viswanatha
Keyword(s):  
Ionic Strength ◽  
Sodium Dodecyl Sulfate ◽  
Ethyl Ester ◽  
Sodium Dodecyl ◽  
Reaction Medium ◽  
Protein Ratio ◽  
Low Concentrations ◽  
Dodecyl Sulfate ◽  
Catalyzed Reactions ◽  
Hydrolysis Of

The effect of sodium dodecyl sulfate and sodium decylbenzene sulfonate on the chymotrypsin-catalyzed hydrolysis of N-acetyl-L-tyrosine ethyl ester was investigated. Pretreatment of the enzyme with sodium dodecyl sulfate produces inactivation which is dependent on the ratio of the surfactant to protein. Total loss of activity is achieved at a surfactant to protein (w/w) ratio of 15. Addition of chymotrypsin to a mixture of detergent and substrate does not affect the activity of the enzyme at low concentrations of sodium dodecyl sulfate. An enhancement in the activity is noted at higher surfactant concentrations, presumably due to the increase in the ionic strength of the reaction medium. The reaction of sodium decylbenzene sulfonate with chymotrypsin results in the formation of a series of complexes in an 'all or none' manner. Inactivation of the enzyme is noted initially at a surfactant to protein ratio of 1.0 and subsequently at ratios higher than 10. However, considerable activity is retained at surfactant to protein ratios of 3:5. The hydrolysis of N-acetyl-L-tyrosine ethyl ester is considerably influenced by the ionic strength of the medium. Increases in the ionic strength cause an enhancement in Vmax without affecting the affinity of the enzyme for the substrate.

Sign in / Sign up

Export Citation Format

Share Document