Insights into the action of the superfamily of cholesterol-dependent cytolysins from studies of intermedilysin.

ABSTRACT: The cholesterol-dependent cytolysins (CDCs), a superfamily of pore-forming toxins, are characterized by a conserved undecapeptide motif that is believed to be critical for membrane recognition by means of cholesterol. Intermedilysin (ILY), an unusual member of the CDCs, exhibits specificity for human cells and contains nonconservative substitutions in the motif. We show that the cellular specificity of ILY is based on its ability to specifically bind to human cells and does not involve some other feature of the CDC mechanism. Furthermore, cellular recognition by ILY appears to be encoded in domain 4 alone but does not involve the variant undecapeptide of ILY. We show that the undecapeptide is involved in the prepore-to-pore conversion of ILY and so demonstrate a direct connection between t

SUBMITTER: Polekhina G 

PROVIDER: S-EPMC545513 | biostudies-literature | 2005 Jan

REPOSITORIES: biostudies-literature