Proteins that promote penetration into mammalian cells. Unlike simple adhesins, which are often lectin-like, interaction of the invasins with host cell surface molecules promotes active internalization involving cytoskeletal rearrangement. For example, the AfaD invasin of pathogenic E. coli interacts with α5–β1 integrin and thus probably activates integrin-linked kinase. The internalins of Listeria monocytogenes are invasins and functionally similar molecules (see thrombospondin-related anonymous protein) are found on apicomplexan parasites.
Subjects: Medicine and Health — Chemistry.