TY - JOUR
T1 - Pathogenesis of shigella diarrhea
T2 - Rabbit intestinal cell microvillus membrane binding site for shigella toxin
AU - Fuchs, George
AU - Mobassaleh, Munir
AU - Donohue-Rolfe, Arthur
AU - Montgomery, Robert K.
AU - Grand, Richard J.
AU - Keusch, Gerald T.
PY - 1986
Y1 - 1986
N2 - This study examined the binding of purified 125I-labeled shigella toxin to rabbit jejunal microvillus membranes (MVMs). Toxin binding was concentration dependent, saturable, reversible, and specifically inhibited by unlabeled toxin. The calculated number of toxin moleculars bound at 4°C was 7.9 x 1010 (3 x 1010 to 2 x 1011)/μg of MVM protein or 1.2 x 106 per enterocyte. Scatchard analysis showed the binding site to be of a single class with an equilibrium association constant, K, of 4.7 x 109 M-1 at 4°C. Binding was inversely related to the temperature of incubation. A total of 80% of the labeled toxin binding at 4°C dissociated from MVM when the temperature was raised to 37°C, but reassociated when the temperature was again brought to 4°C. There was no structural or functional change of MVM due to toxin as monitored by electron microscopy or assay of MVM sucrase activity. These studies demonstrate a specific binding site for shigella toxin on rabbit MVMs. The physiological relevance of this receptor remains to be determined.
AB - This study examined the binding of purified 125I-labeled shigella toxin to rabbit jejunal microvillus membranes (MVMs). Toxin binding was concentration dependent, saturable, reversible, and specifically inhibited by unlabeled toxin. The calculated number of toxin moleculars bound at 4°C was 7.9 x 1010 (3 x 1010 to 2 x 1011)/μg of MVM protein or 1.2 x 106 per enterocyte. Scatchard analysis showed the binding site to be of a single class with an equilibrium association constant, K, of 4.7 x 109 M-1 at 4°C. Binding was inversely related to the temperature of incubation. A total of 80% of the labeled toxin binding at 4°C dissociated from MVM when the temperature was raised to 37°C, but reassociated when the temperature was again brought to 4°C. There was no structural or functional change of MVM due to toxin as monitored by electron microscopy or assay of MVM sucrase activity. These studies demonstrate a specific binding site for shigella toxin on rabbit MVMs. The physiological relevance of this receptor remains to be determined.
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U2 - 10.1128/iai.53.2.372-377.1986
DO - 10.1128/iai.53.2.372-377.1986
M3 - Article
C2 - 3755421
AN - SCOPUS:0022485795
SN - 0019-9567
VL - 53
SP - 372
EP - 377
JO - Infection and Immunity
JF - Infection and Immunity
IS - 2
ER -