Topography of Diphtheria Toxin's T Domain in the Open Channel State
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چکیده
منابع مشابه
Topography of Diphtheria Toxin's T Domain in the Open Channel State
When diphtheria toxin encounters a low pH environment, the channel-forming T domain undergoes a poorly understood conformational change that allows for both its own membrane insertion and the translocation of the toxin's catalytic domain across the membrane. From the crystallographic structure of the water-soluble form of diphtheria toxin, a "double dagger" model was proposed in which two trans...
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Low pH triggers the translocation domain of diphtheria toxin (T-domain), which contains 10 α helices, to insert into a planar lipid bilayer membrane, form a transmembrane channel, and translocate the attached catalytic domain across the membrane. Three T-domain helices, corresponding to TH5, TH8, and TH9 in the aqueous crystal structure, form transmembrane segments in the open-channel state; th...
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Cellular entry of diphtheria toxin is a multistage process involving receptor targeting, endocytosis, and translocation of the catalytic domain across the endosomal membrane into the cytosol. The latter is ensured by the translocation (T) domain of the toxin, capable of undergoing conformational refolding and membrane insertion in response to the acidification of the endosomal environment. Whil...
متن کاملThe Number of Subunits Comprising the Channel Formed by the T Domain of Diphtheria Toxin
In the presence of a low pH environment, the channel-forming T domain of diphtheria toxin undergoes a conformational change that allows for both its own insertion into planar lipid bilayers and the translocation of the toxin's catalytic domain across them. Given that the T domain contributes only three transmembrane segments, and the channel is permeable to ions as large as glucosamine(+) and N...
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The T domain of diphtheria toxin, which extends from residue 202 to 378, causes the translocation of the catalytic A fragment (residues 1-201) across endosomal membranes and also forms ion-conducting channels in planar phospholipid bilayers. The carboxy terminal 57-amino acid segment (322-378) in the T domain is all that is required to form these channels, but its ability to do so is greatly au...
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ژورنال
عنوان ژورنال: Journal of General Physiology
سال: 2000
ISSN: 0022-1295,1540-7748
DOI: 10.1085/jgp.115.4.421