Evidence That Eosin-5-maleimide Binds Close to the Anion Transport Site of Human Erythrocyte Band 3: A Fluorescence Quenching Study

Biochemistry ◽  
1995 ◽  
Vol 34 (14) ◽  
pp. 4880-4888 ◽  
Author(s):  
Rui-jun Pan ◽  
Richard J. Cherry
Keyword(s):  
Fluorescence Quenching ◽  
Human Erythrocyte ◽  
Band 3 ◽  
Anion Transport ◽  
Transport Site

scholarly journals The minimal structure containing the band 3 anion transport site. A 35Cl NMR study.

1985 ◽  
Vol 260 (24) ◽  
pp. 13294-13303 ◽  
Author(s):  
J J Falke ◽  
K J Kanes ◽  
S I Chan
Keyword(s):  
Band 3 ◽  
Anion Transport ◽  
Nmr Study ◽  
Minimal Structure ◽  
Transport Site

A role for band 4.2 in human erythrocyte band 3 mediated anion transport

Biochemistry ◽  
1993 ◽  
Vol 32 (38) ◽  
pp. 10078-10084 ◽  
Author(s):  
Saira Malik ◽  
Malkit Sami ◽  
Anthony Watts
Keyword(s):  
Human Erythrocyte ◽  
Band 3 ◽  
Anion Transport

Further Studies on Zn2+-Mediated Domain–Domain Communication in Human Erythrocyte Band 3

1998 ◽  
Vol 18 (5) ◽  
pp. 265-277
Author(s):  
Hong Xu ◽  
Xujia Zhang ◽  
Fu Yu Yang
Keyword(s):  
Conformational Change ◽  
Human Erythrocyte ◽  
Cytoplasmic Domain ◽  
Band 3 ◽  
Anion Transport ◽  
Intrinsic Fluorescence ◽  
Transport Activity ◽  
Membrane Domain ◽  
Nmr Study ◽  
Anion Transport Activity

Human erythrocyte band 3 is purified and reconstituted into vesicles, forming right-side-out proteoliposomes. Zn2+ entrapped inside the proteoliposomes inhibits the anion transport activity of band 3, and removal of the cytoplasmic domain of band 3 is able to diminish Zn2+ inhibition. Thus, the inhibition of activity of band 3 results from the Zn2+ induced conformational change of the cytoplasmic domain, which in turn is transmitted to the membrane domain. The results of intrinsic fluorescence and its quenching by HB and the 35Cl NMR study indicate that the cytoplasmic domain is essential for the conformational change induced by Zn2+.SH-blocking reagents, CH3I and GSSG, are used to modify the cytoplasmic domain, where they specifically bind to Cys201 and Cys317. It is observed that the Zn2+ induced inhibition of anion transport activity is blocked. This demonstrates that Cys201 and Cys317 are required in Zn2+-mediated domain–domain communication.

Inhibition of chloride binding to the anion transport site by diethylpyrocarbonate modification of band 3

1990 ◽  
Vol 116 (1) ◽  
pp. 87-91 ◽  
Author(s):  
Naotaka Hamasaki ◽  
Kenji Izuhara ◽  
Kenshi Okubo ◽  
Yoko Kanazawa ◽  
Akira Omachi ◽  
...  
Keyword(s):  
Band 3 ◽  
Anion Transport ◽  
Chloride Binding ◽  
Transport Site

Proton inhibition of chloride exchange: asynchrony of band 3 proton and anion transport sites?

1986 ◽  
Vol 250 (6) ◽  
pp. C955-C969 ◽  
Author(s):  
M. A. Milanick ◽  
R. B. Gunn
Keyword(s):  
Conformational Changes ◽  
Chloride Concentration ◽  
Band 3 ◽  
Anion Transport ◽  
Band 3 Protein ◽  
Chloride Flux ◽  
Proton Binding ◽  
Chloride Exchange ◽  
Transport Site ◽  
External Ph

The inhibition of chloride exchange at 0 degrees C by protons at the cytoplasmic and the extracellular surface of the band 3 protein of human erythrocytes was measured between pH 4.6 and 7.6. At constant external pH and chloride concentration, internal protons were a mixed inhibitor of chloride flux, with the apparent pK2 = 6.1 for protonation of the inward-facing empty transporter conformation and the apparent pK3 = 5.7 for protonation of the chloride-transporter complex. The activation of chloride exchange by external chloride was inhibited by internal protons, and internal protonation of the externally facing empty conformation had a pK1 = 6.1. External protons were also a mixed inhibitor of chloride exchange with the apparent pK1 = 5.0 for the empty outward-facing transporter conformation. Because of the pHo dependence of self-inhibition, the value of pK3 on the outside for chloride could not be accurately determined, but the apparent pK3 for protonation of the iodide-transporter complex on the extracellular surface was 4.9. The data support a mechanism with a single proton binding site that can alternatively have access to the cytoplasmic and extracellular solutions. It appears that this proton binding and transport site can be coupled to the single anion transport site for cotransport, but the two sites can be on opposite sides of the membrane at the same time and thus can be asynchronously transported by conformational changes of band 3.

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