N-(4-Azido-2-Nitrophenyl)-2- Aminoethylsulfonate (NAP-Taurine) as a Photoaffinity Probe for Identifying Membrane Components Containing the Modifier Site of the Human Red Blood Cell Anion Exchange System
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چکیده
I N T R O D U C T I O N In the preceding paper (Knauf et al., 1978), it was found by kinetic analysis that in the dark external NAP-taur ine appears to inhibit red cell anion exchange reversibly by acting at a nont ranspor t ing site, called the modif ier site (Dalmark, 1976). Inasmuch as NAP-taur ine contains an aryl azide, which can be activated by light to form a highly reactive nitrene, it should be possible to use this c o m p o u n d to label and thereby identify the componen t containing the modif ier J. GEN. PHYSIOL. 9 The Rockefeller University Press 9 0022-1295/78/1101-063151.00 Volume 72 November 1978 631-649 631 on Jne 9, 2017 D ow nladed fom Published November 1, 1978
منابع مشابه
N-(4-azido-2-nitrophenyl)-2-aminoethylsulfonate (NAP-taurine) as a photoaffinity probe for identifying membrane components containing the modifier site of the human red blood cell anion exchange system
Exposure of cells to intense light with the photoactivatable reagent, N-(4-azido-2-nitrophenyl)-2-aminoethylsulfonate (NAP-taurine), present in the external medium results in irreversible inhibition of chloride or sulfate exchange. This irreversible inhibition seems to result from covalent reaction with the same sites to which NAP-taurine binds reversibly in the dark. As shown in the preceding ...
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In the dark, the photoaffinity reagent, N-(4-azido-2-nitrophenyl)-2-aminoethylsulfonate (NAP-taurine), acts as a reversible inhibitor of red cell anion exchange when it is present either within the cell or in the external solution. A detailed analysis of the inhibition kinetics, however, reveals substantial differences in the responses to the probe at the two sides of the membrane. On the insid...
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A B s x a A C v In the dark, the photoaffinity reagent, N-(4-azido-2-nitrophenyl)-2aminoethylsulfonate (NAP-taurine), acts as a reversible inhibitor of red cell anion exchange when it is present either within the cell or in the external solution. A detailed analysis of the inhibition kinetics, however, reveals substantial differences in the responses to the probe at the two sides of the membran...
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External N-(4-azido-2-nitrophenyl)-2-aminoethylsulfonate (NAP-taurine) inhibits human red cell chloride exchange by binding to a site that is distinct from the chloride transport site. Increases in the intracellular chloride concentration (at constant external chloride) cause an increase in the inhibitory potency of external NAP-taurine. This effect is not due to the changes in pH or membrane p...
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