Rabbit erythrocyte band 3: a receptor for staphylococcal alpha toxin

Abstract

Enzymes known to specifically cleave the band 3 component of the rabbit erythrocyte membrane were found to reduce both the hemolytic sensitivity to and the binding of the alpha toxin of Staphylococcus aureus. Lectins which bind to band 3 also inhibited the toxin. Lectins which do not bind to band 3 have no effect. Purified band 3, isolated by affinity chromatography on a concanavalin A column, was homogeneous by polyacrylamide gel electrophoresis, had a molecular weight of 100 000, and inhibited the hemolytic activity of alpha toxin. Antibodies to the toxin-toxoid receptor were serologically indistinguishable from antiband 3.

Binding of 125I-Alpha Toxin of Staphylococcus Aureus to Erythrocytes

“…Cassidy and Harshman (1976a), however, found that binding to rabbit erythrocytes was temperature dependent with maximum binding at 24°C. The binding reported here was independent of pH, which provides evidence against the hypothesis that the receptors are membrane proteins or glycoproteins (Cassidy and Harshman, 1976a;Kato et al, 1977;Maharaj and Fackrell, 1980), because both receptors and the toxin would exhibit different degrees of ionisation over this pH range, wbich would, in turn, affect binding affinity.…”

“…The receptor is sensitive to pronase (Kato et al, 197%;Cassidy and Harshman, 1976a;Maharaj and Fackrell, 1980), and estimates of the number of copies per cell range from 3.5 x lo3 to 1.25 x lo5 (Cassidy and Harshman, 1976a;Kato et al, 1977;Maharaj and Fackrell, 1980). Bernheimer and Avigad (1980) showed that glycophorin, a major glycoprotein of the erythrocyte membrane, inhibited the cytolytic activity of a toxin, whereas Maharaj and Fackrell (1980) proposed that a second major glycoprotein component of the erythrocyte membrane, band 3 detected by several methods, was the receptor in question. Band 3 is a ubiquitous component of erythrocyte membranes with 5 x lo5 copies per human erythrocyte (Bretscher, 1973) and the resistance to lysis by a toxin was explained in terms of masking of the receptor molecule by other surface components.…”

Differential Action of Staphylococcal Alpha-Toxin on Young and Old Erythrocytes

“…The toxin causes lysis after attachment to band 3, the 100-kD anion transport protein [3]. We suggested [4] that band 3 was a bind ing site for alpha-toxin when we observed that concanavalin A bound specifically to rabbit erythrocyte band 3 and inhibited the hemolyt ic activity of the toxin. Alpha-toxin lost its hemolytic activity after incubation with band 3 and preincubation of rabbit erythrocytes with anti-band 3, rendering them resistant to the toxin.…”

“…Alpha-toxin lost its hemolytic activity after incubation with band 3 and preincubation of rabbit erythrocytes with anti-band 3, rendering them resistant to the toxin. Recently we demonstrated colocali zation of band 3 and the binding site for the toxin [5], Traditionally alpha-toxin is quantified by a hemolytic assay [ 1,6,7] in which the rate of hemolysis is measured either turbidometrically [4,8] or colorimetrically by the release of hemoglobin into the supernatant [6]. How ever, hemolytic assays exhibit considerable variation [6,9].…”

Senescent Erythrocytes Exhibit a Single-Hit Response to Staphylococcal Alpha Toxin

“…We have suggested that Band 3, the 100-kD anion transport protein of erythrocytes, acts as a binding site for alpha toxin [7][8][9][10]. Kay [11] showed that Band 3 is progressively degraded as human erythrocytes age.…”