Oligomerization of membrane-bound diphtheria toxin (CRM197) facilitates a transition to the open form and deep insertion.

ABSTRACT: Diphtheria toxin (DT) contains separate domains for receptor-specific binding, translocation, and enzymatic activity. After binding to cells, DT is taken up into endosome-like acidic compartments where the translocation domain inserts into the endosomal membrane and releases the catalytic domain into the cytosol. The process by which the catalytic domain is translocated across the endosomal membrane is known to involve pH-induced conformational changes; however, the molecular mechanisms are not yet understood, in large part due to the challenge of probing the conformation of the membrane-bound protein. In this work neutron reflection provided detailed conformational information for membrane-bound DT (CRM197) in situ. The data revealed that the bound toxin oligomerizes with increasing DT co

SUBMITTER: Kent MS 

PROVIDER: S-EPMC2257914 | biostudies-literature | 2008 Mar

REPOSITORIES: biostudies-literature